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Effect of Salicylic acid foliar spraying on growth parameters, γ-pyrones, phenolic content and radical scavenging activity of drought stressed Ammi visnaga L. plant
Abstract
The present study was conducted to evaluate the impact of drought stress and foliar spraying of salicylic acid (SA) on the secondary metabolites particularly the γ-pyrones and total polyphenolic content in the different organs of Ammi visnaga L. plant. The following were measured: different growth parameters, γ-pyrones, total polyphenolic content (TPC) and the antioxidant activity of the methanolic extracts. From the results obtained, it was clear that drought stress had a negative impact on growth of the plant and on the yield of the fruits, whereas it caused an increase in the percentage of the two major γ-pyrones: khellin and visnagin in most organs. The adverse effects of drought stress on growth parameters was found to be partially alleviated by the salicylic acid foliar spray. On the other hand, combination of SA foliar spray and normal irrigation gave the highest percentage of khellin (1.544 ± 0.002%) and visnagin (0.902 ± 0.002%), as well as an increase in the yield of fruits per plant. In contrast, drought alone and in combination with SA significantly (p < 0.001) increased the polyphenolic content and the radical scavenging activity. The highest polyphenolic content was recorded in the water stressed aerial parts sprayed with 2 mM SA, where it reached 78.28 ± 0.14 mg/gm dry weight calculated as gallic acid equivalent (GAE). Antioxidant activity, using DPPH assay, was measured for the different plant organs under different treatments where a reduction from 12.967 ± 0.983 to 2.803 ± 0.262 μg/ml in the IC 50 was noted in the drought stressed aerial parts sprayed with 2 mM SA vs the normally irrigated plant. UPLC/MS analysis was used to demonstrate the effect of SA foliar application on the γ-pyrones and total polyphenolic content in Ammi visnaga L. fruits.
... Previous reports indicated that exogenous application of SA, induces the synthesis of PC (P erez et al., 2014). Also, SA affects antioxidant capacity (Osama et al., 2019) and the equilibrium between ROS output and scavenging (Brito et al., 2019). ...
... On the other hand, SA can affect the growth, development, and secondary metabolite production in plants (Khan et al., 2015). Previous studies showed that SA application enhanced plant growth in Carthamus tinctorius L. (Shaki et al., 2018), and Ammi visnaga L. (Osama et al., 2019). According to the research, SA is capable of preventing cytokinin and auxin from reduction, which motivates cell division of the apical root meristem, plant growth, and productivity (Shakirova et al., 2003). ...
... Different lowercase letters indicate a significant difference among the treatments at p < 0.05. application in raising DPPH radical scavenging activity has been reported before (Osama et al., 2019). Moreover, SA-induced antioxidant activity. ...
Salicylic acid is a phenolic plant growth regulator that affects the secondary metabolite production of medicinal plants. Moreover, Zinc is one of the necessary micronutrients that has a positive effect on the growth parameters and physiological characteristics of the plants. This study aimed to evaluate the interaction effects of foliar application (distilled water (as control), ethanol 1 % (as solvent), 1 and 2 mM salicylic acid), and zinc concentrations containing (0 (Zn omission), 0.025, 0.05, and 0.1 mgL À1) on the growth, phenolic compounds profile and antioxidant capacity of the peppermint. Results showed that response of most investigated traits to the application of zinc was differing with the levels of salicylic acid applications. In this experiment, variation among methods of antioxidant activity assay was observed. The highest antioxidant activity based on IC 50 (0.16 mg mL À1) was observed in Zn omission and 1 mM SA application. In contrast, the highest rosmarinic acid (34.23 § 0.04 mg g DW À1) and gallic acid (14.99 § 0.06 mg g DW À1), as the major PCs, were observed in 0.1 mgL À1 Zn and 1 mM SA application. SA application, as an elicitor, can enhance PCs and antioxidant activity of peppermint at the highest Zn level (0.1mgL À1) and Zn omission due to the stress condition of these Zn levels. Overall, these findings indicated that by increasing appropriate Zn levels and sal-icylic acid application, the accumulation of PCs and antioxidant activity of peppermint enhanced.
... Furthermore, SA has been increasingly recognized for its role in enhancing plant tolerance to various abiotic stresses such as salinity, drought, and high temperature [9]. Exogenous SA has been applied to increase bioactive compounds in many plant species such as sweet basil [10][11][12], peppermint [8,13], marjoram [10], amaranth [14], and Ammi visnaga [15]. Te efciency of exogenous SA to induce secondary metabolites depends on many factors. ...
... In contrast, high SA concentration usually causes deleterious efects. However, the optimal SA concentration to induce bioactive compounds in each plant species tends to be specifc, like 0.1 mM SA for sweet basil [12], 0.01 mM SA for amaranth [14], 0.5 mM SA for peppermint [8], and 1 and 2 mM for Ammi visnaga under water shortage and normal irrigation, respectively [15]. Tese values indicate that each plant species shows diferent responses to SA doses. ...
... Jaafari and Hadavi [11] showed that foliar spray of SA three times (at 24, 34, and 44 days after emergence) at the concentrations of 2 and 4 mM did not afect the fresh weight and dry weight of sweet basil. In contrast, exogenous SA application increased plant growth of sweet basil [10,23], marjoram [10], peppermint [8], and Ammi visnaga [15]. Elhindi et al. [23] showed that the application of 1.0 mM SA twice, frst at the seedling stage with 2-3 true leaves and then 5 days after transplanting, signifcantly increased plant height, shoot fresh and dry weight, branch number, and leaf area of sweet basil. ...
Holy basil (Ocimum sanctum L.) has been used extensively in Thai traditional medicine, where it is commonly utilized as a part of herbal remedies for treating various ailments. Cultivation methods using exogenous salicylic acid (SA) to induce secondary metabolites have been documented in various plant species. Nevertheless, there is no reported information available on holy basil. Thus, the present study aimed to investigate the impact of SA foliar application on the bioactive compounds and antioxidant activity of holy basil. SA at concentrations of 0.1, 0.5, 1.0, 1.5, 2.0, and 2.5 mM was foliar sprayed 30 days after transplanting (DAT) compared to spraying with tap water as the control. The plants were harvested at 33 DAT. Exogenous SA at 0.1–1.5 mM enhanced the contents of bioactive compounds and improved antioxidant activity. The highest contents of eugenol (17,829.53 ± 243.11 μg/g dry extract), total phenolics (444.10 ± 2.80 mg GAE/g dry extract), and total flavonoids (382.69 ± 6.49 mg QE/g dry extract) were achieved at 1.0 mM SA foliar application, which was 282.96, 1.76, and 2.14 times, respectively, over control. Furthermore, the greatest antioxidant activity was observed in the 1.0 mM SA treatment. In contrast, the 2.0 and 2.5 mM SA treatments had lower levels of antioxidant activity and bioactive compounds than the control. The results of this study suggest that exogenous 1.0 mM SA foliar application is an effective method to produce enriched bioactivity in holy basil.
... T phenolic compounds, in vacuole and cytoplasm, are in positive correlation with cell membrane stability (Molaei et al., 2012). Numerous reports confirm the enhancement of osmotic adjustments in stress conditions like drought conditions (Marcinska et al., 2013;Khoyerdi et al., 2016;Osama et al., 2019) and salinity tension (Estaji et al., 2018(Estaji et al., , 2019. This increment enhances plant tolerance toward stress conditions. ...
... Over the last years, some farm management plans have been made to develop strategies for decreasing the harmful effects of drought on plant growth, physiology and yield. For that purpose, the exogenous application of phytohormones like jasmonic acid (Bandurska et al., 2003) and SA (Shaki et al., 2018;Osama et al., 2019;Brito et al., 2019) have been tested on some species. Nonetheless, no information has been described how exogenous SA mitigates the effects of drought stress on growth, yield, and oil characteristics of milk thistle plants. ...
... It can be said that the SA application gradually declined the harmful effects of deficit irrigation. Improving plant growth due to the application of SA has also been reported in Safflower (Shaki et al., 2018), Ammi visnaga L. (Osama et al., 2019), and Egletes viscosa L. (Batista et al., 2019). Hussain et al. (2008) also reported higher growth and yield of sunflower plants by SA application, in water definition condition. ...
Water deficit is one of the most sever worldwide problems of agricultural systems, which influences both yield and quality. Applying compositions like salicylic acid (SA) can improve plant resistance against environmental stresses. The present study was conducted to evaluate the impact of irrigation intervals and SA application on plant growth, osmotic parameters, oil yield, and oil composition of milk thistle. A completely randomized design was applied with a factorial arrangement of two factors: irrigation intervals as the first factor, including 5 days (control), 10 days (D1), 15 days (D2), 20 days (D3) and SA application as the second factor, including 0, 0.5 and 1 mM. From the obtained results, it was clear that water deficit damaged plant growth, including relative water content (RWC), seed yield, and oil content. Results show that spraying 0.5 mM SA partially increased plant growth and seed yield parameters under control condition. Under drought stress conditions, spraying 1 mM of SA had more significant effects on higher seed yield and oil content, compared to 0.5 Mm. Drought stress increased proline content, total soluble carbohydrates (TSC), sucrose, total phenolic compounds (TPC), and DPPH free radical scavenging, while applying 1 mM of SA increased these parameters in both well-watered and water deficit conditions. In addition, the production of linolenic acid, palmitic acid, and stearic acid enhanced under drought stress, while linoleic acid and total soluble proteins (TSP) dropped by increasing drought intensity. Applying 1 mM of SA increased all these parameters more effectively than other SA treatments. According to our results, we suggest that SA can play an essential role as a regulator for improving osmotic adjustment, RWC, and yield of milk thistle plants under drought stress conditions. Therefore, the application of a proper amount of SA can be considered as a practical and straightforward strategy for increasing seed oil quality and seed yield, for both industrial and edible purposes, in arid and semi-arid areas.
... It appears that the production and storage of osmolytes like proline contents, sucrose, carbohydratesand phenolic chemicals in the cytoplasm and vacuole plays positiverole to stabilize thecell membrane structure (Molaei et al., 2012). Various studies have found that osmotic adjustments improve under stress circumstances such as drought and salinity (Khoyerdi et al., 2016;Marcińska et al., 2013;Osama et al., 2019;Estaji et al., 2019;Estaji et al., 2018). This increase improves resistance to harsh circumstances among plants. ...
... It is observed that the foliar application of SA gradually decreasesthe harmful effects of drought stress. Previous investigation also showed that SA improves the safflower, Ammi visnaga L. and Egletesviscosa L. growth under water stress (Shakiet al., 2018;Osama et al., 2019;Batista et al., 2019). found that applying SA to sunflower plants increased their growth and yield under water-stressed situations. ...
... Significant secondary metabolites, such as quercetin, kaempferol, rhamnocitrin, and rhamnetin, are known to be present in A. visnaga L., predominantly in its aerial parts. Extensive research has been conducted by multiple investigators, including [12,50], to identify and study these compounds. The presence of phenolic compounds in A. visnaga L. contributes to its potential pharmacological activities and associated health benefits. ...
... Ascorbic acid was used as a positive control at known concentrations (µg/mL). The results were reported as IC 50 values, which were calculated ...
For centuries, plants and their components have been harnessed for therapeutic purposes, with Ammi visnaga L. (Khella) being no exception to this rich tradition. While existing studies have shed light on the cytotoxic and antimicrobial properties of seed extracts, there remains a noticeable gap in research about the antimicrobial, antioxidant, and anticancer potential of root extracts. This study seeks to address this gap by systematically examining methanol extracts derived from the roots of A. visnaga L. and comparing their effects with those of seed extracts specifically against breast cancer cells. Notably, absent from previous investigations, this study focuses on the comparative analysis of the antimicrobial, antioxidant, and anticancer activities of both root and seed extracts. The methanol extract obtained from A. visnaga L. seeds demonstrated a notably higher level of total phenolic content (TPC) than its root counterpart, measuring 366.57 ± 2.86 and 270.78 ± 2.86 mg GAE/g dry weight of the dry extract, respectively. In the evaluation of antioxidant activities using the DPPH method, the IC50 values for root and seed extracts were determined to be 193.46 ± 17.13 μg/mL and 227.19 ± 1.48 μg/mL, respectively. Turning our attention to cytotoxicity against breast cancer cells (MCF-7 and MDA-MB-231), both root and seed extracts displayed similar cytotoxic activities, with IC50 values of 92.45 ± 2.14 μg/mL and 75.43 ± 2.32 μg/mL, respectively. Furthermore, both root and seed extracts exhibited a noteworthy modulation of gene expression, upregulating the expression of caspase and Bax mRNA levels while concurrently suppressing the expression of anti-apoptotic genes (Bcl-xL and Bcl-2), thereby reinforcing their potential as anticancer agents. A. visnaga L. seed extract outperforms the root extract in antimicrobial activities, exhibiting lower minimum inhibitory concentrations (MICs) of 3.81 ± 0.24 to 125 ± 7.63 μg/mL. This highlights the seeds’ potential as potent antibacterial agents, expanding their role in disease prevention. Overall, this study underscores the diverse therapeutic potentials of A. visnaga L. roots and seeds, contributing to the understanding of plant-derived extracts in mitigating disease risks.
... Besides, applying PGRs such as MeJA and uniconazole could minimize the impacts of drought stress on fennel plants by increasing the length of the growth period, photosynthesis, sink capacity in the stem, and possibly remobilization, which led to less reduction in fruit yield and its components than control under moderate and severe drought stress conditions. Osama et al. (2019) indicated that a reduction in the Table 6 Composition of essential oil in fennel fruits under various irrigation regimes using external proline, uniconazole and methyl jasmonate. weights of the Khella (Ammi visnaga L.) fruits were related to the drought-stressed control plants, while foliar application of 2 mM SA significantly increased the weights of fruits in both drought-stressed and irrigated treatments, displaying a 1.10 and 1.2-fold increase, respectively compared with the control. ...
... In contrast, it reduced the content of MDA or electrical conductivity in soybean plants under drought stress. Khalil et al. (2018) in garden thyme and Osama et al. (2019) in Khella revealed that externally applied SA remarkably increased the total polyphenolic content, with the impact being more evident in the drought-stressed plants compared with the normal ones. Besides, Sun and Lin (2010) stated that antioxidant properties had been reported for proteins called dehydrins. ...
Drought stress is a significant environmental constraint that seriously limits crop productivity. A two-year field study was carried out as a split plot based on a randomized complete block design (RCBD) with three replicates in the experimental station of the agricultural faculty of Azarbaijan Shahid Madani University, Tabriz, Iran. This study evaluated the impacts of various irrigation regimes and plant growth regulators/proline on yield, its components, and essential oil content. Water shortage led to considerable decreases in umbels per plant, umbellets per umbel, fruits per umbellet, 1000-fruit weight, biological yield, and finally, fruit yield, despite increases in fruit essential oil content under moderate drought stress conditions. External methyl jasmonate, uniconazole, and proline significantly increased these parameters measured in fennel plants compared with the control. Improved effects of external plant growth regulators/proline tended to be greater in drought-stress plants, as it enhanced yield, its components, and fruit essential oil content compared with control. Foliar spraying, particularly methyl jasmonate, and uniconazole, enhanced e- anethole content under drought stress. Fenchone and methyl chavicol contents increased in plant growth regulators/proline-treated plants when they were kept under moderate drought stress conditions; however, their contents decreased by the severity of drought stress apart from the application of methyl jasmonate. Hence, applying these PGRs or proline could be critical in cultivating fennel plants under water shortage conditions to achieve higher essential oils yield and its constituents, particularly anethole, compared with control.
... SA concussion the water deficit insights through an altered variety of biochemical and physiological processes, which tend to promote tolerance and enhance plant survival (Yazdanpanah et al. 2011). The inclusion of SA during a stressful exposure stimulates the expression of genes about pertaining to antioxidants and secondary metabolites, enhancing the therapeutic efficacy of the plant also (Gorzi et al., 2020a;Osama et al., 2019). Furthermore, enhanced osmolytes synthesis aids plants in counteracting osmotic stress and reviving the water status, including cell membrane stability with the application of SA during water-derived stress (Jahan andRautela, 2022: Hu andXiong, 2014;Lobato et al., 2021). ...
... Although those plants treated with moderate SA during water deficit exposure indicated an enormous increase in ascorbic acid as well as total phenolics in comparison to without SA. Our analyzing results are supported by earlier findings regarding SA's role in terms of phenolics accumulation in different plants such as Ocimum basilicum (Kulak et al., 2021), Ammi visnaga (Osama et al., 2019), and Thymus valgaris (Khalil et al., 2018) when exposed to water deficit stress. It is believed that salicylic acid targets the shikimate pathway, and strikes the phenolics synthesis by regulating the activity of the phenylalanine ammonia-lyase (PAL) enzyme (S anchez-Rodríguez et al., 2011). ...
Salicylic acid (SA), an eminent stress tolerance phytohormone, assists plants in dealing with abiotic stress. A pot experiment was carried out to substantiate the SA's ability to protect the medicinal herb Bacopa monnieri (L.) from exposure to water deficit. Diverse concentrations of SA (50, 75, 100, and 125 mg/l) were applied to plants as a foliar spray along with varied water levels based on reduced irrigation, WD1 (twice a week), and WD2 (once a week) against WW (once a day), with the first spray being applied after one week of water deficit treatment and the second one month later. The pool data for 2021 and 2022 demonstrated the resilience propensity of SA against water deficit in terms of oxidative markers detoxification (H 2 O 2 and MDA) via evoking the antioxidative mechanism of plants. The activity of antioxidants (SOD, CAT, GPOX, and APOX) and amount of non-enzymatic antioxidants (ascorbic acid, total phenolics and, flavonoid) including osmolytes (proline and total soluble sugar) was upsurged after SA (75 mg/l conc.) administration under both stressed and non-stressed plants. Additionally, stressed plants also revealed a recovery in their relative water content with intensifying the membrane stability index. Besides that positive repercussion in terms of medicinally bioactive compound (bacoside-A) content was also achieved with 75 mg/l conc. of SA foliar spray in addition to WD2. Conclusively, the present investigation unraveled the attainment of SA to ameliorate the B. monnieri (L.) under water deficit stress at moderate doses (up to 100 mg/l) by boosting their deterrence mechanisms through counterbalance of the physio-biochemical attributes.
... Salt stress is one of the main factors affecting plant growth and yield [42], which was confirmed by the obtained results. The exogenous SA applied as a spray and to the roots of plants growing under high EC nutrient reduced the weight and number of BERs, affected the increase in root weight of peppers, increased leaf SPAD values, maximum light-adapted fluorescence Fm' and overall PSII-PI viability compared to non-treated plants [43]. Studies by Tahjib-Ul-Arif et al. [44] and Oliveira et al. [45] showed that exogenous SA had a significant effect on cherry tomato fruit production. ...
... Additionally, exogenous SA increased chlorophyll content under drought conditions [47] and salinity [48]. Osama et al. [43] suggested that the regulatory role of SA is connected to the prevention of the reduction of auxin and cytokinin levels, which leads to better cell division of the root apical meristem, thus contributing to the improvement of plant growth and yield. Furthermore, SA can alleviate salt stress by increasing water and nutrient absorption, membrane protection, as it can also interact with ROS signalling pathways and reduce oxidative stress [49] Salinity, similarly to other stresses, stimulates the synthesis of proteins protecting plant tissues, which is a part of the defence mechanism induced in the plant to deal with adverse environments. ...
High electrical conductivity (EC) in cultivation systems with the recirculating nutrient solutions can affect plant growth and development. This study aimed to investigate the effect of salicylic acid (SA) on the selected physiological and biochemical parameters of sweet pepper (Capsicum annum L.) growing aeroponically at standard and high concentrations of nutritive solutions. Four experimental variants were tested: (1) plants cultivated under low EC conditions, (2) plants cultivated under low EC conditions and treated with foliar SA, (3) plants cultivated under high EC conditions, (4) plants cultivated under high EC conditions and treated with SA on leaves and roots. The obtained results revealed that exogenous SA, regardless of EC, reduced the formation of fruits with calcium deficiency symptoms. Furthermore, SA helps plants to cope with high EC nutrient stress through an increase in leaf SPAD index, maximum light-adapted chlorophyll fluorescence and PSII viability. Exogenous SA reduced the number of soluble proteins both under low and high EC; however, increased H2O2 content induced a defence mechanism reflected by the upregulation of antioxidant enzyme activity. The results of the study provide valuable information on the role of SA in the alleviation of the harmful effect of salinity under aeroponic cultivation.
... SA application enhanced amino acids accumulation (proline, serine, threonine, and alanine) as well as carbohydrates accumulation (glucose, mannose, fructose, and cellobiose) . Drought stress negatively affected growth of toothpick plant (Ammi visnaga) plants and fruits yield, whereas increased two major γ-pyrones: khellin and visnagin in most organs (Osama et al., 2019). The detrimental effects of drought stress on growth parameters were reduced by foliar spray of 2 mM SA. SA application significantly increased the polyphenolic content and the radical scavenging activity of plants under drought (Osama et al., 2019). ...
... Drought stress negatively affected growth of toothpick plant (Ammi visnaga) plants and fruits yield, whereas increased two major γ-pyrones: khellin and visnagin in most organs (Osama et al., 2019). The detrimental effects of drought stress on growth parameters were reduced by foliar spray of 2 mM SA. SA application significantly increased the polyphenolic content and the radical scavenging activity of plants under drought (Osama et al., 2019). ...
Salicylic acid (SA) is a multifaceted plant growth modulator that is reported to engage in plant reaction to stresses. Drought is a common environmental constraint of crop growth, influencing global agricultural productivity. Foliar applications of SA have been recorded to improve growth under drought stress in major crops such as cereals (wheat, barley, maize, and rice), oilseed crops (sunflower, safflower, sesame, and flax), legumes (beans, mungbeans, and crown vetch), vegetable crops (cucumber, okra, Chinese cabbage, fennel, and strawberry), medicinal plants (basil and black cumin), some ornamental and non-woody fruit plants, along with other herbs. Foliar applications of SA can reduce the toxic effects of oxidative stress provoked by drought through different mechanisms. First, SA may act by boosting osmolytes, including total soluble sugars and proline, thus maintaining the water status of plants under drought stress. Second, SA may act by improving the enzymatic activity of peroxidase, superoxide dismutase, and catalase (common antioxidant enzymes) often manifested with lower levels of lipid peroxidation, lipoxygenase activity, and H2O2 production. Third, SA may act by maintaining the total chlorophyll content of plants, thus preserving the photosynthetic apparatus of plants. Low concentrations of SA are generally beneficial, but high concentrations can be either detrimental or of no benefit. Recent reports on the improvement of crop tolerance to drought stress with foliar or applications of SA and proposed metabolic pathways for induced tolerance by SA treatments are reviewed.
... In Scenedesmus quadricauda alga exposed to Cu stress, the exogenous SA had no significant effect on TPC (Kováčik et al. 2010). Conversely, SA treatment increased the content of phenolic compounds in seedlings exposed to drought (Osama et al. 2019) and salinity . The phenolic compounds, as ROS scavengers, play an essential role in modulating oxidative stress. ...
... In addition, these compounds chelate heavy metals and reduce their destructive effects on the cell (Michalak 2010). The accumulation of phenolics and the simultaneous intensification of antioxidant capacity in the plants treated with SA emphasize the role of phenolic compounds as antioxidant metabolites (Abbasi et al. 2020;Osama et al. 2019). The increase in the content of phenolic compounds in the plant treated with SA is attributed to an increase in PAL activity known as the enzyme initiating the biosynthetic pathway of free phenolics (Tajic et al. 2019). ...
Due to many uses of zinc oxide nanoparticles (ZnO NPs) in various industries, the release of these particles in the environment and their effects on living organisms is inevitable. In this study, the role of salicylic acid (SA) pretreatments in modulating the toxicity of ZnO NPs was investigated using a hydroponic system. After pretreatment with different concentrations of SA (0, 25, 75, and 150 μM), Chenopodium murale plants were exposed to ZnO NPs (50 mg L−1). The results showed that exogenous SA increased the length, weight, chlorophyll, proline, starch, and soluble sugars in the plants. Besides, SA pretreatments improved water status in the plants treated with ZnO NPs. In SA-pretreated plants, increased activity of catalase (CAT), guaiacol peroxidase (GPX), and superoxide dismutase (SOD) was associated with a decline in electrolyte leakage (EL %) and membrane peroxidation. Under NPs stress, SA pretreatments increased the content of phenolic compounds by increasing the activity of phenylalanine ammonia-lyase (PAL). Exogenous SA reduced the translocation of larger amounts of Zn to the shoots, with more accumulation in the roots. This result can be used to produce healthy food from plants grown in environments contaminated with nanoparticles. It seems that all concentrations of SA reduced the symptoms of ZnO NPs toxicity in the plant by strengthening the function of the antioxidant system and increasing the content of some metabolites. Findings also suggest that SA pretreatment can compensate for the growth reduction caused by ZnO NPs.
... Also, Alshammari et al., 2019 showed that A. visnaga has a great role for treatment of urolithiasis. Osama et al., (2019) concluded that khella baladi has been used in a wide variety of diseases, including kidney stones and the inflammations of the kidney. Qasem, (2020) showed that khella baladi can treat ailments associated with spasm and constriction of ease the passing of kidney stones. ...
... The lowest levels of serum AST, ALT & ALP recorded for hyperoxaluric rats fed on A. visnaga 5.5% with significant difference (p < 0.001) compared to positive control fed on basal diet (Ahmed et al., 2017). These results that obtained confirmed by Osama et al., (2019) showing the least level compared to all groups for urea, creatinine and uric acid was due to group 6 (6% khella baladi) for hyperoxaluric rats by reduced values of these compounds to less levels compared with (+ve) control group, showing a pronounced therapy towards the normal healthy rats. (5) show significant increases in urine (Na&K) and significant decreases serum (Na & K) for (+ve) control group as compared with (-ve) control group. ...
... "Khella" is a widespread flowering plant native to Europe, Asia, and North Africa. 1 The khella seeds have many therapeutic properties in traditional medicine for respiratory conditions including bronchitis, asthma, and cough. [2][3][4] The seeds of this plant contain a furochromone khellin as a major constituent, which is a vasodialator and antispasmodic agent. ...
... Infrared spectra were measured on Fourier transform infrared Nicolet IS10 spectrophotometer (cm À1 ), using KBr disks. 1 H-NMR (300 MHz) and 13 C-NMR (75 MHz) spectra were measured on Mercury-300BB, using dimethyl sulfoxide (DMSO)-d 6 as a solvent and TMS (d) as the internal standard. Mass spectra were obtained using GC-2010 Shimadzu Gas chromatography instrument mass spectrometer (70 eV). ...
Some novel substituted benzofurans and annulated furochromenes were obtained through the treatment of the novel (2E)-3-(4,9-dimethoxy-5-oxo-5H-furo[3,2-g]chromen-6-yl)acrylonitrile (2 A. A. Abu-Hashem, and M. El-Shazly, “Synthesis, Reactions and Biological Activities of Furochromones,” European Journal of Medicinal Chemistry 90 (2015): 633–65.[Crossref], [PubMed], [Web of Science ®] , [Google Scholar]) by some active carbon nucleophiles such as active methylene ketones and methylene nitriles. Thus, the reaction of acrylonitrile 2 with acetylacetone, ethyl acetoacetate, diethylmalonate, and acetoacetanilide in ethanol containing piperidine produced efficiently the corresponding polyfunctionalized benzonitrile derivatives 3–5 and furochromeno-pyridine 6, respectively. Also, treatment of acrylonitrile 2 with some methylene nitriles such as malononitrile, ethyl cyanoacetate, and malononitrile dimer afforded the annulated furochromene derivatives 7–9. Furthermore, the pyrido[1,2-a] benzimidazole system 10 was furnished via reaction of acrylonitrile 2 with 2-(1 H-benzimidazol-2-yl)acetonitrile. These reactions took place through Michael addition, retro-Michael, and γ-pyrone ring opening followed by different types of recyclization. The chemical structures of the novel products were established on the basis of their spectral data and elemental analysis.
... Of course, our results revealed that drought stress alone significantly increased these antioxidant levels in lettuce leaves and spraying them with SA, CA, and MA further boosted this increase (Figures 2A, 3, 4A). Other studies confirm drought stress significantly increases the content of these plant metabolites [128][129][130][131][132][133]. The exogenous application of SA also significantly induced these accumulations in various plant species [98,105,[134][135][136][137]. ...
The aim of this study was to investigate the effects of maleic acid (MA), salicylic acid (SA), and citric acid (CA) on alleviating the drought stress of a lettuce (Lactuca sativa L.) hydroponic culture. The effect of these organic acids was tested under stress conditions induced by polyethene glycol (PEG 6000) at 5% and 7.5% concentrations. Drought stress reduced the fresh and dry matter yields of plants. The acid treatment caused increasing tendencies in the fresh weight yield:control (SA, MA), PEG 7.5% (SA, MA, CA)) and dry weight yield (control (SA, MA), PEG 5% (MA), PEG 7.5% (SA, MA)). The acid treatment also enhanced the nutrient uptake of stressed plants: SA: N (PEG 7.5%), K (PEG 5 and 7.5%); MA: N, P, K, Ca (PEG 5 and 7.5%). This work found that chlorophyll a and b amounts did not change under applied experimental conditions. Most parameters of chlorophyll fluorescence did not depend on either the level of applied water stress (PEG level) or the type of spraying. Drought stress increased leaf superoxide anion (O2•−) and malondialdehyde (MDA) levels but decreased H2O2. Proline (Pro) and phenolic compounds (TFC), including flavonols (Fla), accumulated more in stressed plants. Drought stress also affected the chlorophyll fluorescence. Our results suggest that acids can improve plant tolerance to drought stress by boosting the antioxidant defence system and reducing the oxidative damage caused by reactive oxygen species.
... The results showed that the application of salicylic acid and the increased availability of sulfur in the soil positively affected the synthesis of proteins, increasing the internodal length of the plant and its overall growth. This suggests that salicylic acid and sulfur can be essential in plant development (Ahmad et al. 2011;Ali 2021;Ali et al. 2024;Ghahremani et al. 2023;Khalid et al. 2023;Osama et al. 2019). ...
The total soluble protein-mediated morphological traits in mustard treated with Thiourea and Salicylic acid were investigated. In addition, it tested the hypothesis that the growth regulator salicylic acid protects the photosynthetic apparatus by up-regulating morphological traits. Under natural environmental conditions, seeds were sown in the field, and seed emergence was recorded. For three days after the 15-day stage, plants in the area were treated with thiourea and salicylic acid and allowed to grow for 90 days. Plants were harvested to assess various morphological traits. A follow-up application of SA and Thiourea plants improved plant height, leaf area, internodal length, leaf number, and accelerated plant activity. The up-regulation of morphological traits may have occurred in SA and Thiourea-mediated plants. After treatments, the level of total soluble protein was estimated in the leaves at proposed day intervals.
... It integrates into processes for the growth and development of a plant, delays organ ageing, regulates the source-tosink connection, and participates in specific physiological reactions about absorption of carbon or fixes in the chloroplasts, as well as rubisco activity and concentration (Khalvandi et al., 2021). According to Osama et al. (2019), SA regulatory function is linked to preventing auxin and cytokinin levels from falling, which promotes better cell division in the root apical meristem and enhances plant growth, thus increasing yield. Furthermore, considering that SA contributes to the production of antioxidants, promotes osmotic adjustment, and scavenges ROS. ...
... Also, a decrease in cell division and turgor potential due to drought can result in stunted plant growth. This result is the same as other studies found, which showed that drought stress made Ammi visnaga L. 26 and Nigella sativa L. plants shorter 14 . ...
Soils in arid and semi-arid regions like Iran have suffered greatly from low organic matter content and low water availability. Traditional tillage and the overuse of chemical fertilizers are accelerating the problems in the region. So, sensible and sustainable strategies such as conservation tillage and natural organic inputs are becoming increasingly important to enhance organic matter and humidity in the soil and grow high-quality crops in agroecosystems. Thus, in 2019 and 2020, a split-split plot arrangement within a randomized complete block design was conducted in Iran to assess the effects of irrigated conditions, tillage systems, and biochar on the aforementioned traits. There were two irrigation conditions (irrigated and dryland) as the main plots, three tillage methods (conventional, minimum, and no-tillage) as sub-plots, and two application rates for biochar (0 and 15 ton ha⁻¹) as sub-sub plots. The findings indicated that biochar application enhanced grain yield across all tillage methods under both irrigation conditions. Biochar with minimum tillage improved oil yield by 23% and 29% compared to those that did not use biochar under the dryland and irrigated conditions, respectively. Moreover, oil yield was higher in 2020 than in 2019 for all tillage systems and biochar rates. The main components of Nigella sativa L. oil belong to linoleic, oleic, and palmitic acids. Minimum tillage with biochar under irrigated conditions in 2020 and no-tillage without biochar under dryland conditions in 2019 had the most (59%) and the least linoleic acid (53%), respectively. Conventional, minimum, and no-tillage with biochar in dryland conditions significantly increased linoleic acid by 2%, 3%, and 5% compared to those without biochar in 2020, respectively. In general, adopting biochar with minimum tillage produced the best outcomes for Nigella sativa L. yield, and grain oil quality under both irrigation conditions. It is recommended that farmers incorporate these practices to produce high-quality Nigella sativa L. in sustainable agricultural systems.
... SA induced increase in radical scavenging activity could be due to activation of antioxidant enzymes activities viz. ascorbate peroxidase, superoxide dismutase and catalase might have increased by SA and PUT treatment (Osama et al., 2019). ...
... Following the closure of the stomata and the depletion of water absorption and the RWC, the CT increases due to the reduction of transpiration amount [16,37]. The Increment in proline and carbohydrate contents of camelina leaves can also be related to their role in osmotic regulation under stress conditions [38]. On the other hand, when a plant is subjected to drought stress conditions, the transportation of photosynthetic assimilates to the seeds is decreased [39], and this can be a reason for the accumulation of carbohydrates in the leaves. ...
A factorial experiment was arranged in a randomized complete blocks design with three replicates in 2018–19 and 2019–20 growing seasons in Karaj, Iran to investigate the effects of foliar application of different potassium silicate concentrations (0, 1, 2, 3 g L⁻¹) on camelina plants under different irrigation regimes (optimal water supply, withholding irrigation from formation of silicles, and withholding irrigation from flowering). The results indicated that both restricted irrigation regimes negatively affected the physiologic (relative water content, stomatal resistance, canopy temperature, and total chlorophyll content) and agronomic (number of silicle per plant, number of seed per silicle, 1000-seed weight, seed yield, and water use efficiency) traits as well as oil content, while the potassium silicate alleviated the adverse effects of drought stress on studied traits. The highest camelina seed yield (2521 kg ha⁻¹), water use efficiency (0.492 kg ha⁻¹ m⁻³), and oil content (33.53%) belonged to foliar application of 2 g L⁻¹ under optimal water supply regime. On average across potassium silicate treatments, reductions of 45 and 64%, 27 and 28%, and 6 and 11% were detected for seed yield, water use efficiency, and oil content when irrigation was restricted from silicle formation and flowering stages compared with the optimal water supply regime, respectively. Overall, the foliar application of 2 g potassium silicate L⁻¹ under an optimal water supply regime and 3 g potassium silicate L⁻¹ under drought stress conditions can be recommended to achieve the best performance of camelina.
... The DPPH free radical scavenging activity is a key to check the antioxidant potential. Our results are in line with the results of Osama et al. (2019), who displayed a considerable reduction in DPPH activity on exposure to Cr toxicity in red beans. This decline is due to the overproduction of free radicals. ...
Chromium (Cr) pollution is one of the primary environmental concerns because of its adverse impact on crop productivity. Cr translocate in plants from the rhizosphere and enters the food chain, where it poses a significant hazard to the health of humans. Glutathione (GSH) mediated regulation of the defense mechanism in pea under Cr toxicity has not been reported in the literature. Therefore, the current study was undertaken to evaluate the role of exogenous GSH in alleviation of Cr stress in Pisum sativum L. (pea). Pea seeds were primed with three different concentrations of GSH (25, 50, and 75 μmol L−1GSH). Cr-induced toxicity resulted in a notable reduction in germination rate, biomass production, stomatal conductance, transpiration rate, net photosynthesis and phenolic content in pea seedlings. The findings also revealed that Cr reduced chlorophyll, carotenoids and protein content in seedlings due to decreased uptake of mineral content (Na, K, Mg, Zn). Plants grown from GSH-primed seeds exhibited reduced oxidative damage caused by Cr, through accretion of non-enzymatic antioxidants such as proline and phenolic. Thus, GSH prevented the hampering of plant’s physiological activity, resulted in enhanced germination rate, biomass production, gas exchange attributes, net photosynthesis and protein content. Briefly, 50 μmol L− 1GSH priming provided best outcomes by increasing germination rate (33%), protein content (6.12 µg g−1 FW), proline content (18.01 µmol g−1 FW) and phenolic (0.493 mg g−1 FW). Consequently, GSH improved pea growth by enhanced nutrient uptake along with reduced Cr content in shoot. The current study reveals that GSH primed seeds minimizes Cr toxicity and makes it possible to cultivate pea in Cr-contaminated areas. Future studies will probably assist in elucidation of GSH intervened stress alleviation procedures in pea crop. Furthermore, research with reference to GSH for stress mitigation in other agronomic and horticultural crops will help in improvement of crop productivity.
... The beneficial effect of salicylic acid is possibly associated with its role in enzymatic and photosynthetic activities, thus maintaining the balance between the production and elimination of reactive oxygen species (Batista et al., 2019). Furthermore, SA acts as a regulator in physiological and biochemical plant processes, preventing reductions in the levels of auxins and cytokinins and favoring higher cell division in the root apical meristem (Osama et al., 2019). When evaluating application methods of salicylic acid, Silva et al. (2022b) observed that the fortnightly foliar application of SA (1 mM) resulted in the highest values for MFW (3.3 g per fruit), TP (114.5 g per plant), and EFD (16.6 mm) in cherry tomato plants (Solanum lycopersicum L.) irrigated with saline water. ...
Considering the relevance of bell pepper and the limitations imposed by the deleterious effects of salt stress, especially in semi-arid regions, it is extremely important to establish strategies that can facilitate the use of saline water in vegetable production. In this scenario, this study aimed to evaluate the effect of the frequency of foliar application of salicylic acid on the morphophysiology and production of the bell pepper cv. “All Big” irrigated with saline water. The study was conducted at a greenhouse in Campina Grande - PB. The treatments were distributed in a completely randomized design and set up in a 4 × 4 factorial arrangement with three replications, corresponding to four application frequencies of salicylic acid (F1- No application of salicylic acid, F2 - Weekly application, F3- fortnightly application, and F4- monthly application) and four levels of electrical conductivity of irrigation water - ECw (0.8, 1.6, 2.4 and 3.2 dS m-1). The fortnightly application of salicylic acid at a concentration of 1.0 mM mitigated the effects of salt stress on the morphophysiology and production components of bell pepper cv. All Big cultivated with ECw of up to 2.4 dS m-1, which reinforces the hypothesis that salicylic acid can act as a signaling molecule and reduce the effects of saline stress in bell pepper, enabling the use of brackish water in agricultural activity, mainly in semi-arid regions of northeastern Brazil, which have a shortage of fresh water.
... [89] Lemon balm Melissa officinalis L. Lamiaceae Exogenous application of salicylic acid significantly mitigated the toxic effects of mercury on growth. [90] Longan Dimocarpus longan Lour. Sapindaceae ...
Biostimulants are one of the most important substancesfor improving productivity, growth and yield of plants as well as heavy metal detoxification, and stimulating natural toxins, controlling pests and diseases and boosting both water and nutrient efficiency. Google Scholar, Science Direct, CAB Direct, Springer Link, Scopus, Web of Science, Taylor and Francis, and Wiley Online Library have been checked. The search was done to all manuscript sections according to the terms "Salicylic acid," "Humic acid," "Fulvic acid," "Biostimulants" and "Plant growth promotion." On the basis of the initial check, Titles and Abstracts were screened on the basis of online literature, and then articles were read carefully. Salicylic acid may have important roles in abiotic stresses such as salinity, drought, cold, heavy metal and heat stresses, and it has been considered an important environmentally-sound agent with tremendous economical benefits and rapid responses. The positive effects of the application of salicylic acid have been reported in crops such as ajwain, alfalfa, anthurium, artemisia, artichoke, barley, bean, black mustard, broad bean, chickpea, chicory, canola, coriander, corn, cotton, cucumber, cumin, fennel, fenugreek, goji, longan, milk thistle, millet, onion, pea, pepper, pistachio, radish, rice, rosemary, rye, safflower, saffron, savory, sorghum, soybean, spinach, strawberry, sugar beet, tomato, wheat, etc. Humic acid can improve and stimulate plant growth and yield, suppress diseases and promote more resistance to stresses. Fulvic acid can increase root system and promote seed germination, growth rate and final yield. The present manuscript highlights the most important impacts of salicylic acid, humic acid, and fulvic acid ,emphasizing their roles in modern sustainable crop production.
... The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity of the various fractions was measured by Osama et al. (2019) with some modifications. Briefly, four different polar fractions (FDPF) were used at concentrations of 0.2, 0.3, 0.4, 0.5, and 0.6 mg/ml. ...
Walnut green husk (WGH) is rich in natural compounds and is valued as a potential source of antioxidant and antimicrobial properties. In this study, the antioxidant and antimicrobial activities of petroleum ether polar fraction, dichloromethane polar fraction, ethyl acetate polar fraction (EAPF), and n‐butanol polar fraction from WGH were analyzed. The results showed that EAPF exhibited the highest total flavonoid content (65.74 ± 1.01 mg rutin equivalents [RE]/g dry weight [DW]) and total phenol content (48.73 ± 1.09 mg gallic acid equivalent [GAE]/g DW), with the highest 2,2‐diphenyl‐1‐picrylhydrazyl, hydroxyl radical (•OH), and 2,2‐azino‐bis‐3‐ethylbenzothiazoline‐6‐sulfonate scavenging activity compared with other fractions. EAPF also showed good antibacterial activity against Escherichia coli and Bacillus cereus vegetative cells, with a diameter of inhibition zones of 33.5 and 37.6 mm, respectively, a minimum inhibitory concentration of 31.25 mg/ml and a minimum bactericidal concentration of 62.5 mg/ml, which inhibited the growth of both bacteria. Analysis of the antibacterial mechanism demonstrated that EAPF damaged the integrity of the cell membrane, increased the membrane permeability, and triggered the leakage of intracellular material. In addition, ultrahigh performance liquid chromatography‐tandem with mass spectrometry analysis revealed that 8 polyphenols and 14 flavonoids were mainly present in EAPF, such as chlorogenic acid (C16H18O9), gallic acid (C7H6O5), vanillic acid (C8H8O4), ferulic acid (C10H10O4), epicatechin (C15H14O6), catechin (C15H14O6), hesperetin (C16H14O6), naringenin (C15H12O5), hyperin (C21H20O12), luteolin (C15H10O6), and so on. Therefore, WGH had the potential to be developed as a natural antioxidant and antibacterial material.
Practical Application
Our work indicates that WGH contains abundant flavonoids and polyphenols compounds. Therefore, the plant byproducts like WGH may have a promising application as a source of antimicrobial and antioxidant additives.
... Our results showed significantly higher values for total phenolic compounds with the application of SA 2 mM treatment in 'Hybrid' marigold than the control; thus, this can be linked to its biosynthesis chemical alternation, which can improve the production of altered groups of secondary metabolites, such as terpenes, alkaloids, flavonoids, and phenolic compounds [2]. Foliar application of salicylic acid has significant effects on plant secondary metabolites and found a positive linear relationship between phenolic content and salicylic acid concentrations [49]. ...
Marigolds (Calendula officinalis L.) are valuable in ornamentation, human food, and other uses; to enhance productivity, plant growth regulators produce stimulatory effects, including sali-cylic acid (SA) and spermidine (SP), but there is a lack of scientific evidence about such effects in marigolds. The study assessed, under greenhouse conditions, changes in physico-chemical parameters , enzymatic activity, and bioactive compounds of marigold cvs. Hybrid and French marigolds were sprayed of SA (1 and 2 mM) and SP (2 and 3 mM) and compared to control (pure water). The SA at 2 mM improved leaf length (8.20 cm), flower height and diameter (5.32, 8.28 cm), flower fresh and dry weight (14.30, 1.5 g), and the maximum number of flower petals (55) in 'Hybrid'. Similarly, 2 mM SA gave the maximum number of leaves (40.71) and stem thickness (5.76 mm) in 'French', but 3 mM SP promoted the maximum plant height in 'Hybrid'. Superoxide dismutase, peroxidase, and catalase activities increased in 'Hybrid' with 2 mM SA; with this SA dose, 'Hybrid' had higher contents of total phenolic compounds (68.34 mg GAE g −1), antioxidants (77%), carotenoids (110 mg 100 g −1), and flavonoids (67.5 mg RE g −1) than the control. The best dose for improving growth in both marigold varieties was 2 mM SA.
... In a high temperature environment, SA treatments of ornamental pepper crops increase the germination rate and germination potential, and they reduce oxidative damage to seeds [9]. Additionally, SA remarkably increases the total polyphenolic content and potentiates the radical scavenging activity of Ammi visnaga L. when grown in drought-stress conditions [10]. In tomato plants, SA treatments obviously alleviate cadmium-induced growth inhibition by decreasing the cadmium accumulation and malondialdehyde (MDA) level as well as increasing CAT activity and chlorophyll content [11]. ...
China has the largest sweet potato planting area worldwide, as well as the highest yield per unit area and total yield. Drought is the most frequently encountered environmental stress during the sweet potato growing season. In this study, we investigated salicylic acid (SA)-mediated defense mechanisms under drought conditions in two sweet potato varieties, Zheshu 77 and Zheshu 13. Drought stress decreased growth traits, photosynthetic pigments and relative water contents, as well as the photosynthetic capability parameters net photosynthetic rate, stomatal conductance and transpiration rate, whereas it increased reactive oxygen species production, as well as malondialdehyde and abscisic acid contents. The application of SA to drought-stressed plants reduced oxidative damage by triggering the modulation of antioxidant enzyme activities and the maintenance of optimized osmotic environments in vivo in the two sweet potato varieties. After SA solution applications, NCED-like3 expression was downregulated and the abscisic acid contents of drought-stressed plants decreased, promoting photosynthesis and plant growth. Thus, foliar spraying an appropriate dose of SA, 2.00–4.00 mg·L−1, on drought-stressed sweet potato varieties may induce resistance in field conditions, thereby increasing growth and crop yield in the face of increasingly frequent drought conditions.
... Salicylic acid also acts by regulating physiological and biochemical processes in plants, preventing the reduction of auxin and cytokinin levels, leading to a better cell division of the root apical meristem, thus promoting plant growth and yield (Osama et al., 2019). ...
Salt stress caused by excess salts present in irrigation water, is one of the biggest barriers in agricultural production, especially in semi-arid regions. Thus, the use of substances, such as salicylic acid, that minimize the deleterious effects of salinity on plants can be an alternative to ensure satisfactory production. In this context, the objective of this study was to evaluate the effects of different methods of application of salicylic acid on the growth, production and water use efficiency of cherry tomato plants under salt stress. The study was conducted in a greenhouse, using an Entisol soil with a sandy loam texture. The treatments were distributed in a completely randomized design, in a 2×4 factorial arrangement, corresponding to two levels of electrical conductivity of irrigation water - ECw (0.6 and 2.6 dS m-1) and four methods of application of salicylic acid (Control - without application of SA; via spraying; via irrigation and via spraying and irrigation), with five replicates and one plant per plot. The salicylic acid concentration used in the different methods was 1.0 mM. Application of salicylic acid via foliar spraying increased the growth, production and water use efficiency of cherry tomato plants. The salt stress induced by the electrical conductivity of 2.6 dS m-1 was attenuated by the foliar application of salicylic acid. The use of water of 2.6 dS m-1 associated with the application of salicylic acid via irrigation water further intensified the adverse effects of salinity on cherry tomato plants.
... Medicinal plants accumulate secondary metabolites under drought stress as it was reported in Hypericum perforatum to accumulate hyperforin, Catharanthus roseus accumulates indole alkaloids, and roots of Glycyrrhiza uralensis accumulate glycyrrhizic acid (Zobayed et al. 2007;Jaleel et al. 2008). In addition, phenolic compounds increased by drought stress in Brassica napus L. (Bouchereau et al. 1996), Trachyspermum ammi L. (Azhar et al. 2011), Vitis vinifera L. , and Ammi visnaga L. (Osama et al. 2019). Moreover, it was found that alkaloids were induced by SA in Catharanthus roseus (Godoy-Hernández and Loyola-Vargas 1997). ...
Salicylic acid (SA) is considered as a signaling molecule in plants, and plays an important role in abiotic stress signaling. Several studies have been done to identify the protective role of the application of SA exogenously under drought stress. Studies showed that the ameliorating effect of SA is not always clear concerning the drought tolerance of plants. The exogenous application of SA regulates several aspects of growth, influences several physiologic processes, and induces changes at the molecular level. The major role of SA‐induced tolerance to drought is related to regulation of transcription factors and expression of many drought‐related genes. The impact of exogenous SA application depends on several factors such as the developmental stage and plant species, the level of drought stress, and the SA concentration and its endogenous level in the studied plant. This chapter explores the differential role of SA in mediating both the physiological and molecular mechanisms in plants under drought stress conditions.
... However, the adverse environmental conditions including limited water disturb the balance by overproduction of ROS and induce oxidative stress. Under stress conditions, establishment of an enhanced antioxidant capacity is a well-known protective strategy that lets plants to avoid oxidative damage and increase tolerance against stress Results of the current investigation showed that stressed plants contained the higher amounts of phenolics and exhibited more free radical and FRAP activities (Fig. 4).Accumulation of phenolic compounds in response to drought stress has also been reported in basil (Ghasemi Pirbalouti et al. 2017), purple coneflower (Darvizheh et al. 2019) and Ammi visnaga L. (Osama et al. 2019). Moreover, we have also found that exogenous NO-mediated further increments in the levels of phenolic compounds and antioxidant activities (Fig. 4). ...
Water deficit is one of the most detrimental environmental challenges that seriously impacts plant growth and agricultural productivity. In the current investigation, alterations induced by drought stress and exogenous application of sodium nitroprusside (SNP), as a NO donor, at the physiological, biochemical and molecular levels were studied in lemon balm (Melisa officinalis L.) plant. Partial fragments of chlorophyllide a oxygenase (CAO) and Rubisco activase (RCA) genes were also isolated and sequenced in this study. Obtained results showed that limited water markedly induced oxidative damage and decreased the chlorophyll content and the level of relative water content (RWC) of the plant and resulted in significant inhibition of growth parameters. However, exogenous NO ameliorated the adverse impacts of limited water and accompanied with the better plant growth. Under this condition, supplementation of NO elevated both enzymatic and non-enzymatic antioxidant systems as indicated by increasing in activities of superoxide dismutase and catalase and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals and ferric reducing antioxidant power (FRAP) capacities and greater accumulation of phenolic compounds. In this regard, stressed plants treated with NO exhibited lowered levels of lipid peroxidation, hydrogen peroxide and electrolyte leakage, increased transcript abundance of RCA and chlorophyll synthase (CHLG) genes and higher free proline and RWC levels. Results of the present study may be helpful in understanding mechanisms involved in NO-mediated drought adaptability in lemon balm.
... Interestingly, almost the totality of the compounds belongs to the flavonoids class, mainly flavones and flavanols, with the exception of peak no. 5 p-Coumaroyl-hexoside and peak no. 9, which are phenolic acids derivatives. 10 out of them were previously reported among the polyphenolic content of Apiaceae plants [7,[29][30][31][32][33][34][35], and only one, for example, peak no. 4, luteolin-glucoside in edible A. leucotrichus from Algerian Sahara. Four apigenin derivatives were found in the extract: peaks no. 2 and 3 (λ = 330 nm; [M-H] − m/z 473) were inferred to be apigenin-(acetyl)hexoside, confirmed by the presence of a fragment at m/z 269, corresponding to apigenin aglycone with the loss of 42 amu (acetyl moiety). ...
Ammodaucus leucotrichus Cosson & Durieu, known as Sahara cumin, is a plant belonging to the Apiaceae family with a very strong smell of anise growing in the maritime sands in the countries of North Africa. The present work aims to study the polyphenolic profile of its seeds hydroalcoholic extract along with the determination of the antioxidant and antiglycation properties. The phytochemical screening revealed the presence of 16 compounds, out of which 15 have been detected in this extract for the first time. Luteolin‐glucoside turned out to be the most abundant one (281.32±0.34 mg Kg–1), followed by apigenin‐hexoside (235.06±0.29 mg Kg–1) and luteolin (202.41±0.40 mg Kg–1). In terms of antioxidant activity an IC50 value as high 0.39±0.003 mg AAE mL–1 (w/v) was attained. Further, the antiglycation activity was determined yielding interesting results: at a concentration of 1.5 mg mL–1, the extract showed an antiglycation activity (%I) of 61.86 compared to metformine as positive control (%I = 84.01); on the other hand, increasing the concentration to 10 mg mL–1, the inhibition activity switched to advanced glycation end products formation activation (%I = 41.71). This article is protected by copyright. All rights reserved
... Recently, the effect of drought stress as well as foliar spraying with salicylic acid on A. visnaga metabolites have been recorded. Growing A. visnaga under drought stress conditions have increased the production of total phenolics and visnagin in the fruits, aerial parts and roots, while khellin was significantly have increased in the aerial parts and umbels 16 . ...
... Additionally, by degrading and removing ROS, antioxidant enzymes reduced ROS destructive effects on cell membranes, photosynthetic pigments, proteins, and other macromolecules affecting plant metabolic activities and improved the growth and yield of A. hirtifolium via maintaining membrane stability (Table 3) and photosynthetic pigments (Tables 2 and 3), improving the photosynthetic and respiratory activities of the plant. Improving plant growth due to the application of SA has also been reported in safflower [59], Ammi visnaga [60], and Egletes viscosa [46]. ...
Nowadays, the use of the growth regulator salicylic acid for improving a plant’s resistance to environmental stresses such as drought is increasing. The present study investigated the effect of salicylic acid on the physiological traits, antioxidant enzymes, yield, and quality of Allium hirtifolium (shallots) under drought conditions for three years (2016–2017, 2017–2018, and 2018–2019). The experiment was conducted as a split-plot based on a randomized complete block design with four repeats. Irrigation as the main factor in four levels of 100% (full irrigation), 75% and 50% of the plant water requirements with non-irrigation (dryland), and salicylic acid as the sub-factor in four levels of 0, 0.75, and 1 mmol, were the studied factors in this research. The combined analysis of three-year data showed that drought reduced leaf relative water content (RWC), membrane stability index (MSI), chlorophyll content, onion yield, and increased activity of antioxidant enzymes, proline content, tang, and allicin of shallots. Shallot spraying with salicylic acid improved leaf RWC, MSI, chlorophyll content, and onion yield. The highest yield of onion (1427 gr m−2) belonged to full irrigation and foliar application of 1 mmol salicylic acid. The lowest yield (419.8 gr m−2) belonged to plats with non-irrigation and non-application of salicylic acid. By improving the effective physiological traits in resistance to water deficit, salicylic acid adjusted the effects of water deficit on the yield of shallots. Foliar application of 1 mmol salicylic acid in dryland and irrigation of 50% of the plant water requirement increased onion yield by 15.12% and 29.39%, respectively, compared to the control treatment without salicylic acid.
... p-value < 0.01) (data not shown). In addition to the above, the proline and soluble carbohydrate contents increase when the plant is subjected to drought stress, indicating their role in the osmotic adjustment in the plant (Osama et al. 2019). The correlation results also confirm that withholding irrigation from silique setting and followed by the decreasing water content (RWC) in rapeseed genotypes caused a significant enhancement in proline (r = -0.60, ...
A field experiment (2018–2020) was arranged as factorial split-plot in a RCBD with three replications to assess the influences of potassium silicate on rapeseed genotypes under well-watered and drought stress conditions. Main plots included two regimes of full irrigation and withholding irrigation from silique setting and foliar spray of potassium silicate at two levels of non-application and potassium silicate application (4 g l⁻¹). Subplots contained seven genotypes of WRL-95-13, WRL-95-15, WRL-95-17, WRL-95-20, WRL95-23, WRL-95-28, and Nafis. Drought stress increased stomatal resistance, canopy temperature, soluble carbohydrate content, and proline content; by contrast, the chlorophyll content, relative water content (RWC), seeds per silique, silique per plant, thousand-seed weight, seed yield, and water use efficiency (WUE) were reduced when the rapeseed plants experienced drought stress. The oil content and quality of genotypes were higher in the well-watered irrigation regime than in the drought stress regime. The spraying of potassium silicate helped to improve the growth of rapeseed genotypes by increasing the RWC and chlorophyll content and reducing the stomatal resistance and canopy temperature in both irrigation regimes. The increase in the contents of oleic and linoleic acids and reduction in the contents of erucic acid and glucosinolate caused an enhancement in the oil quality when potassium silicate was applied. Overall, the high quantity and quality of oil can be achieved in rapeseed agroecosystems through full irrigation and spraying potassium silicate.
... [16] Owing to the large number of OH groups in its structure (Figure 2b), rhamnetin can act as an efficient antioxidant and donate a maximum of four electrons and H + to the ROS, thereby stabilizing them. [17] The analysis of the literature indicates that many of the vegetables that have antioxidant properties have in their composition the presence of flavonoids, especially rhamnetin, such as in the following species: Ammi visnaga L., [18] Lycium ruthenicum, [19] Thymus nummularius, [20] Persicaria hydropiper, [21] Moringa oleifera L., [22] Ziziphus mistol, [23] Artemisia campestris, [24] Haplopappus multifolius, [25] Rhaponticoides iconiensis [26] and Salvia L., and are known to contain different flavonoids, particularly rhamnetin. [27] In addition to the plant and herb species mentioned above, rhamnetin is also found in fruits that have antioxidant properties, such as grapes, [28,29] oranges, [29,30] mangoes, [31,32] , seriguela or jackfruit [33] and in fruits of the Prunus genus. ...
Objectives:
Numerous natural products, including rhamnetin, have been studied in recent years owing to the need for new herbal remedies to treat different illnesses. This study aimed to review the salient properties of rhamnetin and its pharmacological potential and possible toxicological effects.
Key findings:
A search carried out in the ScienceDirect database using the term 'rhamnetin' yielded 573 articles published between 1977 and 2021. However, only those studies that mentioned pharmacological activity of rhamnetin were included in this study. As a result of this selection process, this study included reports that describe rhamnetin as a secondary metabolite with several pharmacological properties.
Summary:
Rhamnetin (2-(3,4-dihydroxyphenyl)-3,5-dihydroxy-7-methoxychromen-4-one) is a secondary metabolite, belonging to the flavonoid class, present in various plants and fruits; it has different pharmacological properties, including antioxidant, anticancer, anti-inflammatory, antiviral and antibacterial activity. However, conclusive results on the toxicology of rhamnetin have not been reported yet. Therefore, further research is needed to gather detailed information about the effects of rhamnetin.
... Recently, the effect of drought stress as well as foliar spraying with salicylic acid on A. visnaga metabolites have been recorded. Growing A. visnaga under drought stress conditions have increased the production of total phenolics and visnagin in the fruits, aerial parts and roots, while khellin was significantly have increased in the aerial parts and umbels 16 . ...
... Previous researches' findings that demonstrated the positive role of exogenous salicylic acid treatment on raising antioxidant capacity are supporting our results (Osama et al., 2019). This increment can be justified with the enhancement of TPC and TFC. ...
Recently, due to the valuable and high level of phytochemical compounds such as cannabinoids and other secondary metabolites, the cultivation of Cannabis sativa has increased in the world. The current study was conducted to evaluate the potential role of exogenous salicylic acid (control, 0.01, 0.1, and 1 M) on enhanced production of pharmaceutically important phytochemicals. The sprayed aerial parts were evaluated based on phenolic (TPC) and flavonoids (TFC) contents, antioxidant capacity (by FRAP and DPPH assay), photosynthetic pigments including chlorophyll a, b (Chl a and Chl b), total carotenoids (TCC), and cannabinoid compounds. Quantification of aerial parts metabolites was performed using gas chromatography. The results indicated that phytochemical compounds and antioxidant capacity in C. sativa were influenced by various concentrations of salicylic acid (SA). The highest TPC, TFC, TCC, Chl a, Chl b, and antioxidant capacity were obtained in 1 M treatment, whereas the lowest of them were found in control plants. The major cannabinoids in the analyzed extracts were CBD (19.91%–37.81%), followed by Δ⁹-THC (10.04%–22.84%), and CBL (nd-14.78%). The highest CBD (37.81%) and Δ⁹-THC (22.84%) were obtained in 1 M of SA. These results suggest that the elicitor SA (especially 1 M) was able to improve antioxidant capacity, phytochemicals, and cannabinoid compounds.
... The sample solution of the ethyl acetate fraction of A. modesta (100 μg/mL) non-flowering aerial parts was prepared, the chromatographic separation was conducted on an Acquity UPLC system (Waters) equipped with a reversed-phase BEH C18 column (50 × 2.1 mm, particle size 1.7 μm; Waters), and the analysis was carried out using a binary elution system. Mass spectra were detected between m/z 100-1000 in negative and positive ionization modes on a XEVO TQD triple quadrupole mass spectrometer (Waters Corporation, Milford, USA) [8]. Compounds were recognized tentatively by analyzing their mass data using the Maslynx 4.1 software and making a comparison between their retention time (RT) and mass spectrum with previously reported data. ...
Background
Acacia modesta Wall. ( A. modesta ), often recognized as Phulai, is belonging to family Fabaceae and sub-family Mimosaceae. A. modesta has many beneficial uses. Leaves, wood, flowers, and gum of A. modesta have been used frequently for multiple therapeutic purposes.
Results
The chemical investigation of butanol fraction of A. modesta non-flowering aerial parts yielded Vitexin-2′′- β - D -glucopyranoside and Apigenin-6,8-di- C - β - D -glucopyranoside in a flavone mixture as well as ( β - D -glucopyranosyl (1-3)- β - D -glucopyranosyl)-3- β -hydroxy-11-oxo-olean-12-en-28-oic acid) an oleanane-type triterpenoidal saponin. Metabolite profiling via ultra-performance liquid chromatography-electrospray ionization-mass spectrometry (UPLC-ESI-MS) of the ethyl acetate fraction resulted in recognizing of eighteen compounds tentatively compared with previously published data. Quantitative measurement of the overall value of flavonoids of A. modesta was found to be 2.824 μg/100 μg ± 0.01 calculated as quercetin. The acute toxicity study of the ethanol extract proved that the plant under investigation is safe and nontoxic to the male albino mice used. The anti-hyperglycemic activity of the ethanol extract performed on type 2 diabetic rats proved that the most potent dosage was 200 mg/kg b. wt. after 4 and 4 weeks of treatment respectively compared to metformin. Furthermore, evaluation of the hepato-protective activity of the ethanol extract of the plant under investigation showed that the most potent extract was with a dose level of 200 mg/kg b. wt. after 3 and 10 days of continuous treatment compared to silymarin.
Conclusion
It can be concluded that A. modesta Wall. cultivated in Egypt could be used as a promising anti-diabetic agent and a hepato-protective agent against hepatocellular damage induced by hepatotoxins.
... A decrease in morphological characters of plants and their correlation with yield in drought conditions has been reported in many studies 46 . However, the application of elicitors such as chitosan incited growth and development of plants and enhanced the accessibility and absorb of indispensable nutrients and water, as a result contributing to increased ROS scavenging activities 47 . ...
Thymbra spicata L. (Mediterranean thyme) belonging to the family Lamiaceae, is an important medicinal and aromatic plant. The effects of the foliar applications including control and salicylic acid (2.5 and 5.0 mM) and chitosan (0.5 and 1.0 g/L) under different soil moisture condition on the chemical compositions and yield of essential oil from T. spicata L. were investigated. The essential oil from the aerial parts of the herb was analyzed by GC-FID and GC/MS. The foliar spraying of salicylic acid and chitosan significantly improved essential oil yield (2.5-2.7 mL/100 g dry matter) from 30 % to 60 % compared with control (1.7 mL/100 g). In this study, five major compounds including carvacrol, as the predominant constituent of the essential oil (48.40-79.1 %), γ-terpinene (7.27-25.62 %), limonene (3.62-10.35 %), p-cymene (1.69-6.44 %) and β-caryophyllene (1-1.5 %) were identified in the T. spicata L. essential oil. The carvacrol contents in the essential oil increased in the plants spraying by salicylic acid and chitosan compared with control. The effects of foliar application ×soil moisture conditions significantly affected the essential oil; the highest percentage of carvacrol was obtained from salicylic acid (at 5.0 mM) × deficit water stress. In conclusion, the foliar applications of salicylic acid and chitosan could decrease the harmful effects of water deficit on the essential oil yield and the carvacrol concentration in the T. spicata essential oil.
... Foliar application of salicylic acid stimulated an increase in the number of main stem branches (by 33 and 35%) in Jelitto and Pharmasaat compared to the respective control, respectively (Fig. 2B). This agrees with previous studies reporting that application of salicylic acid significantly enhanced growth parameters, number of branches, and fresh and dry biomass in Tanacetum parthenium L., and Ammi visnaga L. (Mallahi et al., 2018;Osama et al., 2019;Talaat et al., 2014). In the present study, salicylic acid (0.2 mM) increased the number of secondary stem branches (by 51 and 36%) in Jelitto and Pharmasaat following C60 fullerene treatment at 500 mg/L compared to the control group, respectively (Fig. 3C). ...
... The compound was not added during the conduction of the assay, either in solution or foliar. Although, other studies evaluate the application of these compounds by supplying solutions with water or foliar application in times of stress (Damalas, 2019;Kareem, Rihan, & Fuller, 2019;Osama et al., 2019). ...
The objective of this study was to evaluate the photosynthetic and physiological parameters of soybean plants under water deficit after imbibition in different concentrations of salicylic acid during germination. The initial seed quality of the cultivar Bayer®/Tec Irga 6070 RR was evaluated. The soybean seeds were soaked in 25 ml in the salicylic acid solution (SA) for 24 hours and the retention capacities of 30, 50 and 70% were adopted. Under controlled conditions, concentrations of zero, 250, 500, 750 and 1000 µM, evaluating the variables length, fresh and dry mass of root and shoot. In the greenhouse, the concentrations of SA of zero, 500 and 1000 µM were used. After 29 days of the seedling, the stomatal conductance, length, fresh and dry mass of root and shoot were evaluated. The results showed that the uptake of SA in the germination aided seedlings under water deficit. The retention capacity of 30% simulated the water deficit, damaging the physiological parameters of soybean seedlings in both environments. The concentrations of 500 and 1000 µM of SA were efficient in the water deficit for the variables root length, fresh and dry shoot mass.
Milk thistle (Silybum marianum (L.) Gaertn) is a globally and widely used medicinal plant that contains silymarin. This plant has antioxidant, antimicrobial, anticancer, hepatoprotective, cardiovascular‐protective, and neuroprotective effects. Plant quality, yield, and phytochemicals, especially silymarin content, change under various conditions like drought stress. Therefore, this research studied plant growth regulators (PGRs) like salicylic acid, spermidine, and brassinosteroid to increase plant tolerance to drought stress. Experimental treatments include different levels of irrigation (25%, 50%, 75%, and 90% field capacity), and foliar spraying including salicylic acid (75 and 150 mg/L), spermine (70 and 140 mg/L), and brassinosteroid (1 and 1.2 μM), separately, and water as a control and a secondary factor. The results revealed that the highest amount of leaf phenolic compounds was observed in the highest drought stress level (25%) and 75 mg/L salicylic acid application. Furthermore, brassinosteroid at different concentrations and salicylic acid (75 mg/L) increased leaf flavonoid content compared to other treatments. In 50% field capacity, foliar application of salicylic acid (150 mg/L) significantly increased seed yield by approximately 75% compared to control under the same stress level. Brassinosteroid application (1 μM) under 75% field capacity significantly increased the seed's taxifolin amount by 159%. Additionally, salicylic acid noticeably increased the silychristin concentration. The concentration of silydianin in the seed has also been increased under drought stress and foliar spraying with PGRs. Compared to the control, using spermidine below 75% field capacity caused an increase in its concentrations by over seven times. The highest silybin A amount was obtained in 50% field capacity and foliar150 mg/L salicylic acid. Taxifolin, silychristin, silydianin, silybinin B, iso‐silybinin A, and iso‐silybinin B compounds were identified in the seed extract. Generally, foliar spraying using plant growth regulators increased the number of silymarin compounds under drought stress conditions and field cultivation conditions.
The decay of vegetables and fruits causes a major loss to the harvested produce. Synthetic pesticides and fungicides have been used frequently to overcome the degradation in perishable produce. These chemicals are harmful to the environment and human health. Therefore, environmental safe methods and techniques are required to be adopted to maintain the preserve quality of harvested produce, one of such is the application of salicylic acid (SA). SA plays a critical role in the regulation of cascade responses against stress and developmental processes of plants. This chapter emphasizes the biosynthesis and metabolism of the SA in plants. In addition, we have elaborated the role of preharvest factors that affect the postharvest quality of perishable crops. The impact of SA on ethylene production also has been described in detail. SA also plays a significant role in reducing the occurrence of diseases of horticultural produce by promoting systemically acquired pathogen resistance mechanisms. It also modulates antioxidant enzyme activities, thus reducing oxidative stress and increasing horticultural products’ resistance to chilling injury. Therefore, SA may be successfully used as an alternative to toxic synthetic chemicals for postharvest management of fresh horticultural products to improve shelf life and ensure food health.
Salicylic acid (SA) is an imperative plant hormone that regulates plant growth, photosynthesis, and different metabolic processes. SA as a signaling molecule plays an imperative role in plant acclimation against different abiotic stresses. The impact of exogenously applied SA on the processes of photosynthesis under optimal and suboptimal conditions is controversial. The SA application improves the stomatal conductance, electron transportation, and antioxidant activities at lower concentration and thus improves the photosynthetic efficiency. The mode of SA action depends on the plant species, environmental conditions and method, and the dose of SA application. The suboptimal environmental conditions can increase the endogenous SA levels which provide them protection against these conditions. Moreover, exogenously applied SA alleviates the negative effects of different stresses and improves the plants’ photosynthetic efficiency and their acclimation to changing environmental conditions. Therefore, in this chapter, we discussed the role of SA on photosynthesis under normal and stressed conditions.
Abiotic stresses such as drought, salinity, heavy metals, metalloids, cold, UV‐B radiation, etc., are a challenge to crop yields and agricultural productivity. These stresses individually or combined induce several adverse effects in plant growth and development, including biochemical, physiological, and molecular processes, and finally reduce 50–70% of crop yield. Phytohormones such asauxins, brassinosteroids (BRs), abscisic acid (ABA), cytokinins (CKs), (GAs), salicylic acid (SA), ethylene, and gibberellin play a significant role in plants’ growth and alleviate the plant tolerance to different abiotic stresses. In particular, being an endogenous plant growth regulator and a signaling molecule, SA involves in the regulations of plant signaling processes to ameliorate stress tolerance. Thus, in several recent studies, SA has increasingly been acknowledged in improving plant stress‐tolerance via SA‐involved metabolic processes. It is considered a mitigating tool and all‐rounder in plants and also is well known that SA theoretically generates a wide range of metabolic processes in plants under different stress conditions. Although it actively mitigates plants under adverse environmental conditions, SA‐induced plant tolerance remains least discussed. Accordingly, understanding the recent updates of SA mechanism in plants would help to speed up the process of developing plants’ abiotic stress tolerance. According to recent reports, in this book chapter, we present an overview of SA's background and biosynthesis under both different stress and normal conditions in plants. Besides, we review the SA functions in plants and cross‐talk potential mechanisms and finally highlight unexplored aspects of SA significantly.
Introduction
Biostimulants consist of natural ingredients, metabolites of fermentation, micro-organisms, algae or plant extracts, bacteria, mushrooms, humus substances, amino acids, biomolecules, etc.
Methods
In this study, all relevant English-language articles were collected. The literature was reviewed using the keywords of biostimulant, medicinal plant, aromatic plant, natural products, and pharmaceutical benefits from Google Scholar, Scopus, and PubMed databases.
Results
The significant and promoting impact of biostimulants has been reported for different medicinal and aromatic plants, such as salicylic acid for ajuga, artichoke, ajwain, basil, common rue, common sage, common thyme, coneflower, coriander, dendrobium, desert Indian wheat, dragonhead, fennel, fenugreek, feverfew, ginger, groundnut, guava, henna, Iranian soda, lavender, lemon balm, lemongrass, Malabar spinach; seaweed extract on almond, bird, s eye chili; amino acids on artemisia, broccoli, chamomile, beneficial bacteria on ashwagandha; humic acid on black cumin, cannabis, chicory, garlic, gerbera, Hungarian vetch, Moldavian dragonhead, niger plant; chitosan on dragon fruit, marigold, milk thistle, etc. The suggested mechanisms include the stimulatory impacts on the activity of enzymes involved in different biosynthetic processes, the hormone-like activity of biostimulant compounds and the improvement of nutrient uptake of plants.
Conclusion
The current manuscript gives many examples of the potential of biostimulants for medicinal and aromatic plant production. However, further studies are needed to better understand the effectiveness of different biostimulants and foliar applications in sustainable agriculture.
To determine suitable cultivation measures to enrich selenium (Se) and alleviate the Se stress in fruit trees, the effects of different exogenous salicylic acid (SA) concentrations (0, 50, 100, 150 and 200 mg/L) on the growth and Se uptake of grapevine under Se stress were studied. Under Se stress, SA increased the biomass of grapevine to some extent and had a linear relationship with both root and shoot biomass. The chlorophyll content, net photosynthetic rate, transpiration rate, stomatal conductance, and intercellular CO2 concentration of grapevine tended to increase when the concentration of SA was < 150 mg/L and decrease when the concentration of SA was > 150 mg/L. Different concentrations of SA enhanced the activity of superoxide dismutase, while reducing that of peroxidase. It had no significant effect on the catalase activity of grapevine. SA decreased the content of osmotically active substances in grapevine to some extent. SA also increased the contents of total Se, inorganic Se and organic Se in grapevine to some extent, and had a linear or quadratic polynomial relationship with the total Se contents in both roots and shoots. When the SA concentration was 250 mg/L, the total Se contents in the roots and shoots were the highest and increased by 10.41% and 58.46%, respectively, compared with the control. Therefore, exogenous SA could promote the growth and Se uptake of grapevine under Se stress, with 250 mg/L serving as the most effective concentration.
Abiotic pressures such as metal/metalloids, salinity stress, ultraviolet-B radiation and ozone, temperature extremes, and water stress are the most potent limiting factors to sustainable agricultural practices in general and medicinal and aromatic plants in particular. Abiotic stresses alter the plants’ physiological/biochemical and molecular network, which in turn induce abnormalities in plant metabolic processes like growth, photosynthetic potential, development, and yield. Plant stress physiologists are currently engaged in cutting area research for engineering tolerance via the modulation of stress markers by external supplementation of organic and inorganic signaling elicitors. Phytohormones are organic signaling elicitors that control growth and development under a myriad of abiotic stresses in diverse crop plants. Very little attention has been paid on unraveling the mechanisms in medicinal and aromatic plants under abiotic stresses. In particular, the regulatory role of phytohormones is gaining new insights in improving abiotic stress tolerance in medicinal and aromatic plants in which phytohormones mediate the regulation of principal plant metabolic processes. Considering various recent updates, the current chapter highlights the role of phytohormones during environmental stresses in medicinal and aromatic plants. Special attention has been paid on the potentiality of foliar and priming application of phytohormones in imparting abiotic stress tolerance in medicinal and aromatic plants. In addition, some type specimens representing some important medicinal and aromatic plants have also been highlighted. Finally, a conclusion drawn from the present piece of collected literature at the end shows how phytohormones impart abiotic stress tolerance. The present review may elucidate new underlying mechanisms of phytohormone-mediated abiotic stress tolerance in medicinal and aromatic plants.
Environmental stresses are crucial restricting ecological factors that limit the growth, development, and effectiveness of plants. Secondary metabolites (SMs), as organic compound, do not have a direct role in the growth and development of plants; however, they play a vital role in plants to cope with various stresses. Salicylic acid (SA), which is produced in plants naturally, acts in very low concentrations. It is available commercially and can be used as a plant growth regulator and mitigating agent in plants that are under stressful conditions. It affects the biochemical and physiological aspects of plants. Accurate application of SA on plants regulates the SM biosynthesis in them and induces high level of protection against various stresses. In this chapter, we explore SMs’ elicitation under abiotic stress and elicitation of SMs by exogenously applied SA under abiotic stress.
Plants are subjected to various abiotic stresses, such as drought, extreme temperature, salinity, and heavy metals. Abiotic stresses have negative impact on the physiology and morphology of plants through defects in the genetic regulation of cellular pathways. Plants employ several tolerance mechanisms and pathways to avert the effects of stresses that are triggered whenever alterations in metabolism are encountered. Phytohormones are among the most important growth regulators; they are known for having a prominent impact on plant metabolism, and additionally, they play a vital role in the stimulation of plant defence response mechanisms against stresses. Exogenous phytohormone supplementation has been adopted to improve growth and metabolism under stress conditions. Recent investigations have shown that phytohormones produced by root-associated microbes may prove to be important metabolic engineering targets for inducing host tolerance to abiotic stresses. Phytohormone biosynthetic pathways have been identified using several genetic and biochemical methods, and numerous reviews are currently available on this topic. Here, we review current knowledge on the function of phytohormones involved in the improvement of abiotic stress tolerance and defence response in plants exposed to different stressors. We focus on recent successes in identifying the roles of microbial phytohormones that induce stress tolerance, especially in crop plants. In doing so, this review highlights important plant morpho-physiological traits that can be exploited to identify the positive effects of phytohormones on stress tolerance. This review will therefore be helpful to plant physiologists and agricultural microbiologists in designing strategies and tools for the development of broad spectrum microbial inoculants supporting sustainable crop production under hostile environments
Myricaria bracteata Royle, Tamaricaceae, is a species with a wide geographic range that encompasses Eastern Europe, Western and Central Siberia, Central Asia, and the Himalayas. This plant is used in traditional folk medicine in Russia (Siberia) and in China typically as an analgesic and for the treatment of some infections and certain types of intoxication. The aim of this study was to identify phenolic constituents of the leaves of M. bracteata from two considerably distant populations. Chromatographic profiles of the leaves of M. bracteata were analyzed for the first time. Seventeen compounds, mainly methyl ethers of quercetin (isorhamnetin, rhamnazin), kaempferol (kaempferide, rhamnocitrin), and ellagic acid as well as quercetin, quercetin 3-glucoside, kaempferol, luteolin, chrysoeriol, citric acid, gallic acid, methyl gallate, ethyl gallate, and ferulic acid were identified in hydrolyzed aqueous ethanol extracts of the leaves. Flavonols and ellagic acid were the major compounds in both samples. Isorhamnetin was the main flavonoid constituent. Kaempferide and rhamnazin were also abundant in the flavonoid complex of the leaves of M. bracteata from the Altai. This study shows that M. bracteata leaves are a source of flavonoids with possible biological activities.
Mitochondria are known for their role in ATP production and generation of reactive oxygen species (ROS), but little is known about the mechanism of their early involvement in plant stress signalling. The role of mitochondrial succinate dehydrogenase (SDH) in salicylic acid (SA) signalling was analysed using two mutants; disrupted in stress response 1 (dsr1) which is a point mutation in SDH1 identified in a loss of SA signalling screen, and a knockdown mutant (sdhaf2) for SDH assembly factor 2 that is required for FAD insertion into SDH1. Both mutants showed strongly decreased SA-inducible stress promoter responses and low SDH maximum capacity compared to wild type; while dsr1 also showed low succinate affinity, low catalytic efficiency and increased resistance to SDH competitive inhibitors. The SA-induced promoter responses could be partially rescued in sdhaf2, but not in dsr1, by supplementing the plant growth media with succinate. Kinetic characterisation showed that low concentrations of either SA or ubiquinone binding site inhibitors increased SDH activity and induced mitochondrial H2O2 production. Both dsr1 and sdhaf2 showed lower rates of SA-dependent H2O2 production in vitro in line with their low SA-dependent stress signalling responses in vivo. This provides quantitative and kinetic evidence that SA acts at or near the ubiquinone binding site of SDH to stimulate activity and contributes to plant stress signalling by increased rates of mitochondrial H2O2 production, leading to part of the SA-dependent transcriptional response in plant cells.
A rapid and accurate HPLC method was developed for determination of both Khellin and Visnagin in Ammi visnaga L. extracts. The calibration curve of Khellin was linear with correlation coefficient (r 2) = 0.9990; over a concentration range of 53.60 – 355.00 mg/l; with a retention time of 9.19 minutes. While the calibration curve of Visnagin was linear with correlation coefficient (r 2) = 0.9999; over a concentration range of 245.40 – 1533.75 mg/l; with a retention time of 10.77 minutes. The relative standard deviation (RSD) was found to be < 2. The proposed method was validated and successfully applied for simultaneous determination of Khellin and Visnagin in the extracts. The method described is quite suitable for routine analysis -Pyrones in Ammi visnaga L. extracts (prepared by traditional solvent extraction as well as supercritical fluid extraction).
Tea bags including fruits of Ammi visnaga L. are used in Egypt as remedy for the treatment of kidney stones. Our study focuses on developing simple and rapid method utilising HPLC for quantitative estimation of khellol glucoside (KG), khellin (KH) and visnagin (VS) simultaneously. Their concentrations were determined in A. visnaga L. fruits at different developmental stages and in pharmaceutical formulations together with following up them during shelf life. Separation was accomplished using HPLC. Perfect resolution between KG, KH and VS was possible through using a mobile phase consisting of water:methanol:tetrahydrofuran (50:45:5, v/v/v). Peaks were detected at 245 nm. The suggested method for the determination of KG, KH and VS was successful in determining the analytes of interest without any interference of other compounds and matrix. All validation parameters were satisfactory and the procedure was relatively easy and fast as extracts are evaluated without previous steps of purification.
The effects of foliar application of different concentrations of amino acids (tyrosine and phenylalanine) and phenolic acids (trans-cinnamic acid, benzoic acid and salicylic acid) on growth, pigment content, hormones levels and essential oil content of Ammi visnaga L were carried out during two successive seasons. It is clear that foliar application of either amino acids or phenolics significantly promoted the growth parameters in terms of shoot height, fresh and dry biomass, number of branches and number of umbels per plant. The increment of growth parameter was associated with elevated levels of growth promoters (IAA, GA3, total cytokinins) and low level of ABA. The greatest increase in the previously mention parameters was measured in plants exposed to different concentration of phenols particularly in benzoic acid- treated plants. Such effect was concentration dependent. All treatments led to significant increments in yield seeds and oil content. Moreover, Gas Liquid Chromatographic analysis revealed that the main identified components of essential oil were 2,2-dimethyl butanoic acid, Isobutyl isobutyrate,α-Isophorone, Thymol, Fenchyl acetate and Linalool. Phenolics and amino acids treatments resulted in qualitative differences in these components of essential oil.
Scarcity of water is a severe environmental constraint to plant productivity. Drought-induced loss in crop yield probably exceeds losses from all other causes, since both the severity and duration of the stress are critical. Here, we have reviewed the effects of drought stress on the growth, phenology, water and nutrient relations, photosynthesis, assimilate partitioning, and respiration in plants. This article also describes the mechanism of drought resistance in plants on a morphological, physiological and molecular basis. Various management strategies have been proposed to cope with drought stress. Drought stress reduces leaf size, stem extension and root proliferation, disturbs plant water relations and reduces water-use efficiency. Plants display a variety of physiological and biochemical responses at cellular and whole-organism levels towards prevailing drought stress, thus making it a complex phenomenon. CO2 assimilation by leaves is reduced mainly by stomatal closure, membrane damage and disturbed activity of various enzymes, especially those of CO2 fixation and adenosine triphosphate synthesis. Enhanced metabolite flux through the photorespiratory pathway increases the oxidative load on the tissues as both processes generate reactive oxygen species. Injury caused by reactive oxygen species to biological macromolecules under drought stress is among the major deterrents to growth. Plants display a range of mechanisms to withstand drought stress. The major mechanisms include curtailed water loss by increased diffusive resistance, enhanced water uptake with prolific and deep root systems and its efficient use, and smaller and succulent leaves to reduce the transpirational loss. Among the nutrients, potassium ions help in osmotic adjustment; silicon increases root endodermal silicification and improves the cell water balance. Low-molecular-weight osmolytes, including glycinebetaine, proline and other amino acids, organic acids, and polyols, are crucial to sustain cellular functions under drought. Plant growth substances such as salicylic acid, auxins, gibberrellins, cytokinin and abscisic acid modulate the plant responses towards drought. Polyamines, citrulline and several enzymes act as antioxidants and reduce the adverse effects of water deficit. At molecular levels several drought-responsive genes and transcription factors have been identified, such as the dehydration-responsive element-binding gene, aquaporin, late embryogenesis abundant proteins and dehydrins. Plant drought tolerance can be managed by adopting strategies such as mass screening and breeding, marker-assisted selection and exogenous application of hormones and osmoprotectants to seed or growing plants, as well as engineering for drought resistance.
Hypericum perforatum is a well known
medicinal plant. The main pharmacological properties are
due to the presence of naphtodianthrones such as hypericin
and pseudohypericin. Unfortunately the levels of these
compounds vary under different environmental conditions.
Elicitation of in vitro cultures is a useful approach to
enhance and extend production of desirable products.
Therefore, the effects of salicylic acid were characterized
on different explants of H. perforatum L. (cells, calli and
shoots) cultured in vitro. It appears at first that salicylic
acid did not affect growth and development of these
explants. In addition, the production of both hypericin and
pseudohypericin has doubled in elicited cell suspension
cultures but not in the two other cultures. Furthermore,
phenylpropanoids that are among the most frequently
observed metabolites affected upon treatment of in vitro
culture material with elicitors, were produced and the
enzymatic activities of phenylalanine ammonia lyase and
of chalcone isomerase were stimulated upon elicitation.
These effects were dependant of the type of in vitro culture,
the concentration of salicylic acid and the duration postelicitation.
The H. perforatum cells were globally more
sensitive to salicylic acid elicitation when maintained in an
undifferentiated state and particularly in cell suspension
cultures. In the absence of glands considered as the sites of
naphtodianthrones biosynthesis, cells and calli were capable
of producing these compounds. This implies that salicylic
acid could act at biosynthesis level but not for the
accumulation of both hypericin and pseudohypericin.
Consequently, the regulation of this process is more complex
than cited in the literature involving the responsibility
of only Hyp-1 gene, encoding a hypericin biosynthetic
enzyme, cloned and characterized from H. perforatum.
Plant growth and productivity is adversely affected by nature's wrath in the form of various biotic and abiotic stress factors. Water deficit is one of the major abiotic stresses, which adversely affects crop growth and yield. These changes are mainly related to altered metabolic functions, one of those is either loss of or reduced synthesis of photosynthetic pigments. This results in declined light harvesting and generation of reducing powers, which are a source of energy for dark reactions of photosynthesis. These changes in the amounts of photosynthetic pigments are closely associated to plant biomass yield. This review describes some aspects of drought induced changes in morphological, physiological and pigments composition in higher plants.
A field study was carried out from 1995 to 1997 in order to determine the effect of irrigation and water stress imposed at different development stages on vegetative growth, grain yield and other yield components of corn (Zea mays L.). The field trials were conducted on a silty loam Entisol soil, with Pioneer 3377 corn hybrid. A randomised complete block design with three replications was used. Four known growth stages of the plant were considered and a total of 16 (including rain fed) irrigation treatments were applied. The effect of irrigation or water stress at any stage of development on plant height, leaf area index, grain yield per hectare, as well number of ears per plant, grain yield per cob and 1000 kernels weight, were evaluated. Results of this 3-year study show that all vegetative and yield parameters were significantly affected by water shortage in the soil profile due to omitted irrigation during the sensitive tasselling and cob formation stages. Water stress occurring during vegetative and tasselling stages reduced plant height, as well as leaf area development. Short-duration water deficits during the rapid vegetative growth period caused 28–32% loss of final dry matter weight. Highest yields were observed in the fully irrigated control (VTCM) and the treatment which allowed water stress during the vegetative growth stage (TCM). Even a single irrigation omission during one of the sensitive growth stages, caused up to 40% grain yield losses during dry years such as 1996. Much greater losses of 66–93% could be expected as a result of prolonged water stress during tasselling and ear formation stages. Seasonal irrigation water amounts required for non-stressed production varied by year from 390 to 575mm. Yield response factor (ky) values (unitless parameter) relating yield loss to water deficits) obtained for the first, second and third experimental years were determined to be 1.22, 1.36 and 0.81, respectively.
Biotic and abiotic stresses exert a considerable influence on the production of several secondary metabolites in plants; water stress is one of the most important abiotic stress factors. This study was carried out to elucidate the effect of drought stress on growth, physiology and secondary metabolite production in desi ajwain (Trachyspermum ammi L.). Plants were grown in pots and three drought levels (100%, 80% and 60%) of field capacity were created. The experiment was laid out in complete randomized design (CRD) with three replicates. Data on growth, physiological and biochemical parameters were recorded and analyzed statistically. Physiological parameters like transpiration rate and stomatal conductance decreased significantly with increasing water stress levels, but internal CO2 concentration increased. The photosynthetic rate showed non-significant reduction from 100% field capacity to 80% field capacity but increased at 60% field capacity. Growth parameters including plant height, herb fresh and dry weights were reduced significantly with increasing stress levels, while total phenolic contents and chlorophyll contents increased under water stress conditions. These results suggest that cultivation of medicinal plants like desi ajwain under drought stress could enhance the production of secondary metabolites.
A pot experiment was conducted to evaluate the beneficial effect of foliar application of glycine betaine (10mM), grain presoaking in salicylic acid (0.05 M) and their interaction on two droughted wheat (Triticum aestivum L.) cultivars (sensitive, Sakha 94 and resistant, Sakha 93). In general, water stress caused noticeable increases in root length, number of adventitious roots, soluble sugars and nitrogen but a massive reduction in fresh and dry masses of root, growth vigor of shoot, leaf area, pigments content, polysaccharides, protein-N and total nitrogen in both wheat cultivars. Vice versa, exogenous application of GB, SA or their interaction could counteract the adverse effects of drought by improvement of growth vigor of root and shoot, leaf area, retention of pigments content, increasing the concentration of organic solutes (soluble sugars and soluble nitrogen) as osmoprotectants, keeping out the polysaccharides concentration and/or stabilization of essential proteins in both wheat cultivars. Finally, we can conclude that GB, SA or their interaction could improve the drought tolerance of both two wheat cultivars particularly the sensitive ones.
The role of salicylic acid (SA) as a key molecule in the signal transduction pathway of biotic stress responses has already
been well described. Recent studies indicate that it also participates in the signaling of abiotic stresses. The application
of exogenous SA could provide protection against several types of stresses such as high or low temperature, heavy metals,
and so on. Although SA may also cause oxidative stress to plants, partially through the accumulation of hydrogen peroxide,
the results published so far show that the preliminary treatment of plants with low concentrations of SA might have an acclimation-like
effect, causing enhanced tolerance toward most kinds of abiotic stresses due primarily to enhanced antioxidative capacity.
The effect of exogenous SA depends on numerous factors such as the species and developmental stage of the plant, the mode
of application, and the concentration of SA and its endogenous level in the given plant. Recent results show that not only
does exogenous SA application moderate stress effects, but abiotic stress factors may also alter the endogenous SA levels
in the plant cells. This review compares the roles of SA during different abiotic stresses.
Salicylic acid (SA) is a common plant-produced signal molecule that is responsible for inducing tolerance to a number of biotic
and abiotic stresses. An experiment was, therefore, conducted to test whether acetyl salicylic acid (ASA) application at various
concentrations through seed soaking or foliar spray would protect muskmelon [Cucumis melo L. (reticulatus group)] seedlings, subjected to drought stress. Twenty-three-day-old plants pre-treated with ASA (0, 0.1,
0.25, 0.50 or 1.0mM) were subjected to drought stress for 1week in a greenhouse. ASA applied either through seed soaking
or through foliar spray was effective within the range of 0.1–1mM in providing drought stress protection in muskmelon seedlings;
however, there was no difference between application methods indicating that both methods provided similar levels of protection.
ASA significantly affected all seedling growth and stress indicator variables measured except leaf number and root dry weight.
The best protection appeared to be obtained from seedlings pre-treated with lower concentrations of ASA. Even though both
methods provided similar means of protection, due to its simplicity and practicality, soaking muskmelon seeds prior to sowing
in up to 0.5mM ASA would be a more desirable method.
Licorice (Glycyrrhiza glabra L. var. glabra, Fabaceae) is considered as a model plant synthesizing triterpenoid secondary compounds. It is known that glycyrrhizin is
accumulated in thickened intact licorice roots. The effects of methyl jasmonate (MeJa) and salicylic acid (SA) on plant growth
and production of glycyrrhizin in the roots of in vitro cultured 65-day-old plants were studied. Increasing amounts of glycyrrhizin
in the roots treated with MeJa inhibited root growth, while SA increased the amount of glycyrrhizin without negative effects
on growth. Treatment of plantlets with 0.1–2 mM MeJa and 0.1 and 1 mM SA enhanced the production of glycyrrhizin by 3.8 and
4.1 times, respectively, as compared to the controls. Results support the hypothesis that production of glycyrrhizin is related
to a defense response system of the licorice.
Plants would be more vulnerable to water stress and thereafter rewatering or a cycled water environmental change, which occur more frequently under climatic change conditions in terms of the prediction scenarios. Effects of water stress on plants alone have been well-documented in many reports. However, the combined responses to drought and rewatering and its mechanism are relatively scant. As we known, plant growth, photosynthesis and stomatal aperture may be limited under water deficit, which would be regulated by physical and chemical signals. Under severe drought, while peroxidation may be provoked, the relevant antioxidant metabolism would be involved to annihilate the damage of reactive oxygen species. As rewatering, the recoveries of plant growth and photosynthesis would appear immediately through growing new plant parts, re-opening the stomata, and decreasing peroxidation; the recovery extents (reversely: pre-drought limitation) due to rewatering strongly depend on pre-drought intensity, duration and species. Understanding how plants response to episodic drought and watering pulse and the underlying mechanism is remarkably helpful to implement vegetation management practices in climatic changing.
As sessile organisms, plants have evolved mechanisms that allow them to adapt and survive periods of drought stress. One of the inevitable consequences of drought stress is enhanced ROS production in the different cellular compartments, namely in the chloroplasts, the peroxisomes and the mitochondria. This enhanced ROS production is however kept under tight control by a versatile and cooperative antioxidant system that modulates intracellular ROS concentration and sets the redox-status of the cell. Furthermore, ROS enhancement under stress functions as an alarm signal that triggers acclimatory/defense responses by specific signal transduction pathways that involve H(2)O(2) as secondary messenger. ROS signaling is linked to ABA, Ca(2+) fluxes and sugar sensing and is likely to be involved both upstream and downstream of the ABA-dependent signaling pathways under drought stress. Nevertheless, if drought stress is prolonged over to a certain extent, ROS production will overwhelm the scavenging action of the anti-oxidant system resulting in extensive cellular damage and death.
Polyphenolic compounds are considered valuable secondary plant metabolites owing to the myriad of biological activities they exert. This study aimed to investigate the effect of applying various concentrations of the plant growth regulator, salicylic acid (SA), on Thymus vulgaris L. while subjecting the plant to decreasing amounts of irrigation water. The following parameters were monitored; total polyphenolic and flavonoid content, yield and composition of the essential oil, and antioxidant activity of the alcoholic extracts. Drought alone significantly (P < 0.05) increased the polyphenolic and flavonoid content, yield of the essential oil and antioxidant activity. The total flavonoid content in control plants was 6.1 ± 0.3 mg/gm dry weight calculated in terms of rutin equivalent. However, in drought stressed plants, (irrigated at 25% of the field capacity) sprayed with 3 mM SA, the flavonoid content increased to 32.1 ± 0.1 mg/gm dry weight calculated in terms of rutin equivalent. Moreover, the total phenolic content increased from 8.5 ± 0.3 to 68.5 ± 1.2 mg/gm dry weight calculated in terms of gallic acid in the same test plants. Radical scavenging activity, using DPPH assay, was measured for the different plant treatments. A decrease from 74.4 ± 0.4 μg/ml to 36.6 ± 0.9 μg/ml of IC50 was recorded in the drought stressed plants (25% FC) sprayed with 3 mM SA compared with the control plants. The variability in polyphenolic composition between the control plants and plants with the highest total polyphenolic content was investigated by UPLC-ESI-MS/MS. Rosmarinic acid was detected as the major component in samples from both treatments, with a higher percentage observed upon subjecting the plant to the test conditions (25% FC and sprayed with 3 mM SA). The highest yield of the essential oil (1 ± 0.06 %v/w) was obtained from drought stressed plants (25% FC) sprayed with 2 mM SA. GC/MS analysis of oil samples revealed that the Thymol content increased with drought stress, while that of p-cymene decreased. However, an increase of p-cymene was witnessed as a result of SA spraying.
Using a partial equilibrium optimization model, we evaluate the performance of existing and future dams in the eastern Nile River basin (ENRB) for countries consisting of Ethiopia, Sudan, and Egypt. On top of unilateral allocation, we also propose three alternative water rights arrangements (WRAs) with and without intraregional water rights trade and internalizing the resource degradation externality. We found that the social planner would assign the Nile River water for economic sectors and basin countries that could generate more than $10 billion, the highest economic benefit to the region regardless of initial WRA. Unilateral use of Nile water would benefit Ethiopia and Sudan, but it would reduce the economic benefit for Egypt, a country that has relatively efficient irrigated agriculture. In addition, the proposed WRAs and trade could lead to efficiency, recovering up to 99% of the social planner’s outcomes. Allocate-and trade could also be cost-effective alternative to raise around $680 million for short- to medium-term abatement investment that can be used for reducing or eliminating resource degradation problem.
Plants constitute a source of novel phytotoxic compounds to be explored in searching for effective and environmentally safe herbicides. From a previous screening of plant extracts for their phytotoxicity, a dichloromethane extract of Ammi visnaga (L.) Lam. was selected for further study. Phytotoxicity-guided fractionation of this extract yielded two furanochromones: khellin and visnagin, whose herbicidal activity had not been described before. Khellin and visnagin were phytotoxic to model species lettuce (Lactuca sativa) and duckweed (Lemna paucicostata), with IC50 values ranging from 110 to 175 µM. These compounds, also inhibited the growth and germination of a diverse group of weeds at 0.5 and 1 mM. These weeds included five grasses [ryegrass (Lolium multiflorum), barnyardgrass (Echinocloa crus-galli), crabgrass (Digitaria sanguinalis), foxtail (Setaria italica), and millet (Panicum sp.)] and two broadleaf species [morningglory (Ipomea sp.) and velvetleaf (Abutilon theophrasti)]. During greenhouse studies visnagin was the most active and showed significant contact postemergence herbicidal activity on velvetleaf and crabgrass at 2 kg a. i. ha⁻¹. Moreover, its effect at 4 kg a. i. ha⁻¹ was comparable to the bioherbicide pelargonic acid at the same rate. The mode of action of khellin and visnagin was not a light-dependent process. Both compounds caused membrane destabilization, photosynthetic efficiency reduction, inhibition of cell division and cell death. These results support the potential of visnagin, and possibly khellin, as bioherbicides or lead molecules for the development of new herbicides.
Calcium oxalate monohydrate (COM) is the major constituent of kidney stones; it represents about 70% to 80% of all types of human urinary stones. Kidney stone patients are often given aqueous therapy of Ammi Visnaga plant in many middle and near eastern countries. Ammi Visnaga is known in Egypt as (khella). The mode of action of khella as a kidney stone therapy is not well understood. Induction time was determined under different super saturations ranging from 1.63 to 4.51 ratios at 37°C using conductivity method. The results showed that, the induction time decreased exponentially with increasing super saturation ratio whereas the induction time was increased with addition of an aqueous Egyptian khella extract compared to without additive. The surface energy of COM was increased from 7.77 mJ/m² to 9.14 mJ/m² without and with extract addition, respectively. The nucleation rates at a super saturation ratio of 2.79 were 3.14 × 10²⁹ nuclei/cm³.s and 1.54 × 10²⁹ nuclei/cm³.s without and with additive, respectively. The number of molecules required for formation of stable nucleus was calculated depending on the super saturation ratios and the presence of khella extract. The crystallite sizes of the formed crystals without and with additive are 93 nm and 25 nm, respectively.
Ammi visnaga (bisnaga, toothpick weed or khella) belongs to the family Apiaceae and it is a herbaceous medicinal plant. It is found mainly in the Mediterranean regions and also distributed abundantly throughout the world as introduced species. Many times, A. visnaga is weed as well as used in many countries as herbal medicine for different purposes. Ancient records reveal various medicinal properties of A. visnaga as a popular source to cure variety of different ailments. The plant is used directly as a herb or as a component for production of a number of herbal medicines used in the cure of renal colic, ureteric stones, angina pectoris, the coronary vessels, cardiovascular disorders and asthma. Also it is used as a folk medicine for vitiligo and psoriasis. This review highlights the commonly recognized medicinal uses of A. visnaga, its chemistry and ethnobotanical uses and will also serve as ready reference for future research.
Ethanolic extracts of 23 species of the Apiaceae family were analyzed for their flavonoid and isoflavonoid content, using the following methods: high-performance liquid chromatography coupled with mass spectrometry (HPLC-MS); semi-preparative HPLC with Enzyme Linked Immunosorbent Assay (HPLC-ELISA); and immunoaffinity extraction (IAE). Rutin and quercetin-3-glucoside were the most abundant flavonoid glycosides and the most abundant flavonoid aglycone was apigenin. The isoflavonoids daidzein, genistein, sissotrin and formononetin were also found. The estimated content of individual compounds ranged from 1 to over 800 mg/kg (dry weight) for flavonoids, and from 0.2 to over 60 mg/kg for isoflavonoids. The probable reason why isoflavonoids have rarely been reported in the Apiaceae previously is that they occur in far smaller quantities than in families usually associated with isoflavonoids, such as the Leguminosae, but the sensitive methods used made their detection possible.
A survey of over 250 representative taxa in the Umbelliferae has shown that sulphates only accumulate in three genera, Ammi, Daucus and Oenanthe. The presence of quercetin, rhamnocitrin, rhamnetin and isorhamnetin 3-sulphate in Ammi visnaga serves to distinguish it from the related A. majus which lacks sulphates. In Daucus carota leaf, the 7-and 4′-sulphates of luteolin both occur; the two characters are polymorphic and appear to be present more frequently in North temperate than in South temperate populations. Oenanthe is the only genus where sulphates are found abundantly; they occur in 7 of 9 species surveyed. In addition to the known isorhamnetin 3sulphate of O. stolonifera, quercetin 3-sulphate and luteolin 7-sulphate were identified for the first time in the genus. The synthesis of various kaempferol and quercetin sulphates is described.
The medicinal plant Ammi visnaga is a valuable source of furanochromones and pyranocoumarins used as vasodilator agents. Its ability to germinate under unfavourable growth conditions, such as saline soil and hypoxia characterizing clay soils and marshes ecosystems, prompted us to qualitatively characterize secondary metabolites in umbels of A. visnaga plants grown under different conditions (in field, hydroponically controlled, and contrasted by salinity and/or hypoxia) by HPLC-ESI/IT/MS(n) analysis. Subsequently, the quantitative analysis of the bioactive compounds, above all furanochromones and pyranocoumarins, was carried out by HPLC-ESI/QqQ/MS/MS. The results show the influence of growing conditions on the quali-quantitative profile of A. visnaga secondary metabolites and evidence that hydroponic culture leads to increased level of A. visnaga active principles. Furthermore, two furanochromones never reported before were identified and characterized by 1D- and 2D-NMR analysis.
Salicylic acid (SA) acts as an endogenous signal molecule responsible for inducing abiotic stress tolerance in plants. In
this study, the role of SA in improving drought tolerance in two maize cultivars (Zea mays L.) differing in their tolerance to drought was evaluated. The plants were regularly watered per pot and grown until the
grain filling stage (R2) under a rainout shelter. At stage R2, parts of the plants were treated with SA, after which drought
stress was applied. Leaf samples were harvested on the 10th and 17th days of the drought. Some antioxidant enzyme activity,
such as the superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), glutathione reductase (GR), monodehydroascorbate
reductase (MDHAR), dehydroascorbate reductase (DHAR), hydrogen peroxide (H2O2) and malondialdehyde (MDA) content, was measured during the drought period. Exogenous SA prevented water loss and delayed
leaf rolling in comparison with control leaves in both cultivars. As a consequence of drought stress, lipid peroxidation,
measured in terms of malondialdehyde content, was prevented by SA. SA pretreatment induced all antioxidant enzyme activities,
and to a greater extent than the control leaves, during drought. SA also caused a reduction in the ascorbate (ASC) and glutathione
(GSH) content in two maize cultivars. The H2O2 level was higher in SA pretreated plants than the controls in both cultivars. Pretreatment with SA further enhanced the activities
of antioxidant enzymes and the concentrations of non-enzymatic antioxidants in the tolerant cultivar compared with the sensitive
cultivar. Results suggested that exogenous SA could help reduce the adverse effects of drought stress and might have a key
role in providing tolerance to stress by decreasing water loss and inducing the antioxidant system in plants with leaf rolling,
an alternative drought protection mechanism.
The effect of an aqueous extract of Pterospartum tridentatum on the blood glucose levels of normal Wistar rats was investigated in a situation of oral glucose challenge. The extract at 300 mg/kg showed an antihyperglycaemic effect in the first 30 min after glucose challenge but then the blood glucose levels rose above those of the control group, indicating the presence of compounds with different effects on glucose tolerance. Nine compounds of isoflavone and flavonol skeletons were identified in the extract by HPLC-ESI-MSn, four of them being identified for the first time in this species. The isoflavone sissotrin and the flavonol derivative, isoquercitrin, were selected for the oral glucose tolerance test. Isoquercitrin (100 mg/kg) showed time-dependent antihyperglycaemic activity by delaying the post-oral glucose load glycaemic peak at 30 min, as did the sodium-dependent glucose transporter inhibitor phloridzin (100 mg/kg). In contrast, sissotrin (100 mg/kg) showed an opposite effect, impairing glucose tolerance. In conclusion, these preliminary results indicate that the effect of the extract on blood glucose may be either antihyperglycaemic or hyperglycaemic. Additionally, as far as is known, these are the first in vivo results on the acute antihyperglycaemic potential of isoquercitrin. Copyright © 2008 John Wiley & Sons, Ltd.
Worldwide rice productivity is being threatened by increased endeavours of drought stress. Among the visible symptoms of drought stress, hampered water relations and disrupted cellular membrane functions are the most important. Exogenous use of polyamines (PAs), salicylic acid (SA), brassinosteroids (BRs), glycinebetaine (GB) and nitrous oxide (NO) can induce abiotic stresses tolerance in many crops. In this time course study, we appraised the comparative role of all these substances to improve the drought tolerance in rice (Oryza sativa L.) cultivar Super-Basmati. Plants were subjected to drought stress at four leaf stage (4 weeks after emergence) by maintaining soil moisture at 50 % of field capacity. Pre-optimized concentrations of GB (150 mg l−1), SA (100 mg l−1), NO (100 μmol l−1 sodium nitroprusside as NO donor), BR (0.01 μm 24-epibrassinolide) and spermine (Spm; 10 μm) were foliar sprayed at five-leaf stage (5 weeks after emergence). There were two controls both receiving no foliar spray, viz. well watered (CK1) and drought stressed (CK2). There was substantial reduction in allometric response of rice, gas exchange and water relation attributes by drought stress. While drought stress enhanced the H2O2, malondialdehyde (MDA) and relative membrane permeability, foliar spray of all the chemicals improved growth possibly because of the improved carbon assimilation, enhanced synthesis of metabolites and maintenance of tissue water status. Simultaneous reduction in H2O2 and MDA production was also noted in the plants treated with these substances. Drought tolerance was sturdily associated with the greater tissue water potential, increased synthesis of metabolites and enhanced capacity of antioxidant system. Of all the chemicals, foliar spray with Spm was the most effective followed by BR.
Two-year-old seedlings of licorice plant (Glycyrrhiza uralensis Fisch) were exposed to three degrees of water deficit, namely weak (60–70%), moderate (40–50%), and strong (20–30%) relative
water content in soil, whereas control plants were grown in soil with 80–90% water content. Moderate and strong water deficit
decreased the net photosynthetic rate, stomatal conductance, and biomass production. Water use efficiency and the root-to-shoot
ratio increased significantly in response to water deficit, indicating a high tolerance to drought. Weak water deficit did
not decrease root biomass production, but significantly increased the production of glycyrrhizic acid (by 89%) and liquiritin
(by 125%) in the roots. Therefore, a weak water deficit can increase the yield of root medical compounds without negative
effect on root growth.
Keywords
Glycyrrhiza uralensis
–biomass production–gas exchange–glycyrrhizic acid–liquiritin–water deficit
The hypothesis that physiologically activeconcentrations of salicylic acid (SA) and itsderivatives can confer stress tolerance in plants wasevaluated using bean (Phaseolus vulgaris L.) andtomato (Lycopersicon esculentum L.). Plantsgrown from seeds imbibed in aqueous solutions (0.1--0.5 mM) of salicylic acid or acetyl salicylic acid(ASA) displayed enhanced tolerance to heat, chillingand drought stresses. Seedlings acquired similarstress tolerance when SA or ASA treatments wereapplied as soil drenches. The fact that seedimbibition with SA or ASA confers stress tolerance inplants is more consistent with a signaling role ofthese molecules, leading to the expression oftolerance rather than a direct effect. Induction ofmultiple stress tolerance in plants by exogenousapplication of SA and its derivatives may have asignificant practical application in agriculture,horticulture and forestry.
MECC separation of 11 coumarins has been achieved by use of a running electrolyte at pH 10.4 prepared from 50 mM boric acid,
10 mM sodium tetraborate and 100 mM sodium hydroxide. The buffer solution contained 50 mM SDS and, as organic modifier 1%n-propanol. The applied voltage was 25 kV and the temperature of the capillary was kept constant at 20°C. HPLC baseline separation
of the coumarin mixture was obtained by use of a reversed-phase column and an acetonitrile-water solvent gradient. UV detection
was performed at 205 nm. Peak assignment and purity control were achieved by HPLC-mass spectrometry with either an electrospray
interface or an atmospheric-pressure chemical-ionization interface. Compounds were detected in either negative- or positive-ion
modes. These MECC and HPLC-MS methods are suitable for ‘fingerprint’ analysis of a number of coumarin-containing plants, e.g.
Fr.Ammi visnagae, Rd.Scopoliae and Rd.Imperatoriae.
During a search for bioactive compounds from indigenous plants,Pimpinella monoica (Umbelliferae) was found to contain furocoumarin, isopimpenellin (3) and five biogenetically related furocoumarins viz khellin
(1), visnagin (2), visamminol (4), ammiol (5) and khellol (6). Labelled (i) and (2) were isolated from [1−14C]- and [2−14C]-acetates. Labelling pattern, determined by degradation of biosynthesised compounds, establishes the polyketide origin of
their aromatic and pyrone rings while the furan ring originates via an acetate-mevalonate pathway. The plant also utilises
glycine and leucine as substratevia acetate. Biotransformation of [3−3H]-visnagin to (6) but not to (2) was also observed.
The antiradical activities of various antioxidants were determined using the free radical, 2,2-Diphenyl-1-picrylhydrazyl (DPPH*). In its radical form. DPPH* has an absorption band at 515 nm which dissappears upon reduction by an antiradical compound. Twenty compounds were reacted with the DPPH* and shown to follow one of three possible reaction kinetic types. Ascorbic acid, isoascorbic acid and isoeugenol reacted quickly with the DPPH* reaching a steady state immediately. Rosmarinic acid and δ-tocopherol reacted a little slower and reached a steady state within 30 min. The remaining compounds reacted more progressively with the DPPH* reaching a steady state from 1 to 6 h. Caffeic acid, gentisic acid and gallic acid showed the highest antiradical activities with a stoichiometry of 4 to 6 reduced DPPH* molecules per molecule of antioxidant. Vanillin, phenol, γ-resorcylic acid and vanillic acid were found to be poor antiradical compounds. The stoichiometry for the other 13 phenolic compounds varied from one to three reduced DPPH* molecules per molecule of antioxidant. Possible mechanisms are proposed to explain the experimental results.
Current research indicates that both salicylic acid (SA), a likely signal in the response of plants to stress, and phenylalanine ammonia-lyase (PAL; EC 4.3.1.5), a key enzyme in phenylpropanoid metabolism, perform defense-related functions within plants. However, very little is yet know about the role SA might play in regulating PAL expression and phenylpropanoid biosynthesis. The present experiment was performed using in vivo infiltration of 150 μM salicylic acid into entire postharvest grape berries (Vitis vinifera L. cv. Cabernet Sauvignon). The results indicated that SA activated PAL by enhancing the accumulation of PAL mRNA, as well as enhancing the synthesis of a new PAL protein and enzyme activity. Further, the activation was found to be time course-dependent. A significant accumulation of phenylpropanoids was also observed in the SA-treated berries. However, the induction of PAL expression and the accumulation of phenylpropanoids could be blocked by pretreatment with the protein synthesis inhibitor cycloheximide, mRNA transcription inhibitor actinomycin D, and PAL inhibitor 2-amino-2-indanophonic acid (AIP), respectively. These results further indicated that SA could induce PAL mRNA accumulation and as a result, enhance PAL protein amounts and activity as well as enhancing the accumulation of phenylpropanoids such as phenolic acids.
Water stress is known to increase the secondary metabolites concentration in plant tissues and severe water stress conditions may cause oxidative stress due to the formation of reactive oxygen species and photoinhibitory damage. Current study was undertaken to evaluate the changes in the physiological status especially the photosynthetic efficiency and the biochemical profile of the leaf tissues of St. John's wort (Hypericum perforatum) plants exposed to water stress. The net photosynthetic rates of the leaves of plants grown under a water stress condition were significantly low compared with those of the control. The maximal quantum efficiency of PSII photochemistry () of the dark adopted leaves was similar for both wilted and recovered plants although these values were significantly low compared with those of the control. The leaf tissues of the plants under a water stress condition had a significantly higher capacity to detoxify oxygen radicals with an about 2.5-fold increase over the antioxidant potential of the leaves of non-treated (control) or recovered plants. In the leaf tissues of plants grown under a water stress condition, both hypericin and pseudohypericin concentrations reduced with time and on Day 12 of the treatment, the concentration was significantly lower than that of the control; in contrast, the hyperforin concentration increased significantly and the value was nearly double after 12 days of the treatment. Under a water stress condition, the hyperforin concentration was about 70-fold higher than the total hypericins concentration in the leaf tissues; in case of control it was only 10–12 times higher. The results also indicate that the major secondary metabolite, hyperforin concentration of 62-day-old plants was three- to four-fold higher than the previously reported values for 1–2-year-old field-grown plants.
The sensitivity of seed composition to drought was compared among three spring glasshouse-grown rapeseed genotypes by applying water shortage treatments at various stages of development. All traits under study associated with the biochemical composition of the seed were drastically modified in plants subjected to drought during flowering. Water shortage during a restricted period in the early stages of vegetative growth was also important for seed quality. Despite limited fluctuations in total lipid content, changes in fatty acid composition were found, especially in the erucic acid metabolic pathway (i.e., oleic, gadoleic and erucic acids). A slight increase in seed protein concentration was observed after early vegetative and flowering drought treatments. The total sugar content of seeds was not significantly affected by water deprivation. Significant effects of drought stress, depending on its timing, were observed in the accumulation of secondary metabolites (i.e., phenolics and glucosinolates) which are of major importance for rapeseed meal quality. The relevance of the observed effects on seed composition resulting from either immediate or long-term effects of water deprivation depending on its application stage is discussed.
Previous studies have shown that salicylic acid (SA) plays a role in the response of plants to diverse conditions. Therefore, a factorial experiment block design was conducted to investigate the effects of foliar spray of salicylic acid (10−6 and 10−4 M) on fruit productivity and quality of pepper grown in a moderately salt-stressed greenhouse. SA application at low concentration (10−6 M) positively increased the foliage fresh and dry weight, fruit number, average fruit weight, fruit yield, vitamin C, carotenoids content, cuticle thickness of fruit pericarip and translocation of sugars from leaves to fruits. It was found that SA treatment (10−6 M) caused a reduction in peroxidase and increasing of invertase activities of pepper leaves and fruits. According to these results it is expected that, SA treatment regulated sugar contents (translocation from source to sink) and antioxidants and thus reduced stress-induced inhibition of plant growth.
The treatment of wheat plants with 0.05 mM salicylic acid (SA) increased the level of cell division within the apical meristem of seedling roots causing an increase in plant growth and an elevated wheat productivity. It was found that SA treatment caused accumulation of both abscisic acid (ABA) and indoleacetic acid (IAA) in the wheat seedlings but did not influence cytokinin content. SA treatment reduced the damaging action of salinity on seedling growth and accelerated reparation of the growth processes. SA-treatment diminished changes in phytohormones levels in wheat seedlings under salinity. It prevented any decrease in IAA and cytokinin contents and thus reduced stress-induced inhibition of plant growth. A high ABA level was also maintained in SA-treated wheat seedlings providing the development of antistress reactions, for example, maintenance of proline accumulation. Thus SA's protective action includes the development of antistress programs and acceleration of growth processes recovery after the removal of stress factors.
Deficit irrigation (DI) has been widely investigated as a valuable and sustainable production strategy in dry regions. By limiting water applications to drought-sensitive growth stages, this practice aims to maximize water productivity and to stabilize – rather than maximize – yields. We review selected research from around the world and we summarize the advantages and disadvantages of deficit irrigation. Research results confirm that DI is successful in increasing water productivity for various crops without causing severe yield reductions. Nevertheless, a certain minimum amount of seasonal moisture must be guaranteed. DI requires precise knowledge of crop response to drought stress, as drought tolerance varies considerably by genotype and phenological stage. In developing and optimizing DI strategies, field research should therefore be combined with crop water productivity modeling.
The present study was concentrated on the production of secondary metabolites in callus, cell suspension and hairy roots of Ammi majus L. by exposing them to elicitors: benzo(1,2,3)-thiadiazole-7-carbothionic acid S-methyl ester (BION®) and autoclaved lysate of cell suspension of bacteria—Enterobacter sakazaki. GC and GC–MS analysis of chloroform and methanol extracts indicated a higher accumulation of umbelliferone in the elicited tissues than in the control ones. Using GC–MS, two compounds not earlier found in A. majus tissues were identified in callus cultures: scopoletin (7-hydroxy-6-metoxy-2H-1-benzopyron-2-one) and dehydrogeijerin (7-methoxy-6-(3-methyl-1-oxo-2-butenyl)-2H-1-benzopyran-2-one).
Plant secondary metabolites are unique sources for pharmaceuticals, food additives, flavors, and industrially important biochemicals. Accumulation of such metabolites often occurs in plants subjected to stresses including various elicitors or signal molecules. Secondary metabolites play a major role in the adaptation of plants to the environment and in overcoming stress conditions. Environmental factors viz. temperature, humidity, light intensity, the supply of water, minerals, and CO2 influence the growth of a plant and secondary metabolite production. Drought, high salinity, and freezing temperatures are environmental conditions that cause adverse effects on the growth of plants and the productivity of crops. Plant cell culture technologies have been effective tools for both studying and producing plant secondary metabolites under in vitro conditions and for plant improvement. This brief review summarizes the influence of different abiotic factors include salt, drought, light, heavy metals, frost etc. on secondary metabolites in plants. The focus of the present review is the influence of abiotic factors on secondary metabolite production and some of important plant pharmaceuticals. Also, we describe the results of in vitro cultures and production of some important secondary metabolites obtained in our laboratory.
In arid and semi-arid regions where water availability is a major limitation, using plants with low water consumption is one way to manage available water efficiently. Chamomile (Matricaria recutita L.) may be considered as an economical crop for fields with water scarcity due to its considerable adaptability to a wide range of climates and soils. A field experiment was conducted during 2007-2008 using complete randomized block design with four replications in order to evaluate the effect of drought stress on agro-morphological characters (fresh flower weight, dried flower yield, shoot weight and root weight), oil content, oil composition and apigenin content of chamomile. Drought stress had four different levels of soil moisture depletion (30%, 50%, 70% and 90%). Analysis of variance showed that drought stress decreased plant height, flower yield, shoot weight and apigenin content but it had no significant effect on oil content or oil composition. Impacts of drought stress on growth indices were evaluated as well and the results indicated that plant managed to maintain potential for biomass production under the drought stress. Growth analysis results as well as phytochemical properties of this plant showed that despite decrease in agronomical traits, chamomile could be proposed as a moderate drought resistant medicinal plant with a reasonable performance.
Problem statement: Seedlings of Amaranthus hybridus cv. NHAC-3 (large green, amaranth) and Lycopersicum esculentum cv. Roma (tomato) were subjected to 7 days water stress at Early Vegetative (EV), Late Vegetative (LV), Early Flowering (EF) and Late Flowering (LF) stages of growth to study the impact on leaf water potential (ψ<SUB>w</SUB>), Nitrate Reductase Activity (NRA), growth (plant height, shoot and root biomass) and proline content of both plants. Approach: Two concentrations of salicylic acid (1 and 3 mM SA) were applied to stressed plants to study the level of protection given by SA to the plants. Leaf ψ<SUB>w</SUB> was significantly reduced (p = 0.05) during stress treatment at nearly all stages of growth in both plants. Leaf ψ<SUB>w </SUB>was in the range -0.25 to -1.42 (unstressed) and -1.45 to -2.02 (stressed) in tomato plants while in amaranth it was -0.7 to -1.62 (unstressed) and -1.62 to -2.68 (stressed). As 3 mM SA increased leaf ψ<SUB>w</SUB> to values close to the control (unstressed plants). NRA was significantly (p = 0.05) reduced by stress treatment at the LV stage of amaranth, EF stage of tomato and LF stage of both plants. Results: Thus, the reduction of NRA was more pronounced at the reproductive stage of both plants. As 3 mM SA was effective in maintaining NRA at levels similar to the control in both plants. Stress treatment reduced plant height significantly (p = 0.05) at the vegetative stages of both plants and 3 mM was also effective in keeping plant height similar to the control. Though shoot biomass was affected by water stress, SA treatment was not very effective in preserving the biomass during stress. Root biomass of plants was reduced by stress treatment at the reproductive stage and only tomato plants responded positively to 3 mM SA. Proline content was only slightly increased at all stages of growth in stressed plants but 3 mM SA induced a two-fold increase in proline content at the vegetative stage of tomato (EV and LV) and significant increases (p = 0.05) at almost all stages of growth of amaranth. Conclusion/Recommendations: The build up of proline, an osmolyte, by SA in stressed plants increased the capacity of plants to absorb water from the soil as shown by the increase in leaf ψ<SUB>w</SUB> of both plants from -1.45 to -0.25 . SA was more effective in protecting the plants against the adverse effects of water stress when the stress was given at the vegetative stages (EV and LV) than at the flowering stages (EF and LF).