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Pathogenicity assays carried out on basil plants under artificial conditions. Leaves and seedlings were inoculated with sterile distilled water (a), or with conidium suspensions of nine Plectosphaerella species, including P. alismatis (b), P. citrulli (c), P. cucumerina (d), P. delsorboi (e), P. melonis (f), P. oratosquillae (g), P. pauciseptata (h), P. plurivora (i), or P. ramiseptata (j).
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From 2012-2016 plants of basil (Ocimum basilicum L.) and parsley (Petroselinum sativum Hoffm.) showing decline symptoms were collected from local markets in Foggia Province (southern Italy) and assessed to determine their main fungal pathogens. These plants showed symptoms including leaf yellowing, necrotic lesions on stems, collar and roots, and i...
Contexts in source publication
Context 1
... delsorboi, P. melonis and P. oratosquillae did not produce any symptoms on parsley leaves. All of the fungi that were pathogenic on parsley leaves produced necrotic symptoms, as necrotic parenchyma patches with hydropic rings (Figure 2). ...
Citations
... However, Cephalosporium serrae, Gliocladium cibotii and several Acremonium species are included in the family 7 . Some species, such as fruit, tomato, pepper, bamboo, and asparagus, are pathogens on plants 8 . Plectosphaerella cucumerina is the most frequent pathogen of several plant species, causing fruit, root and collar rot and collapse. ...
... Although Plectosphaerella spp. were initially isolated from plants (from healthy or symptomatic tissue), subsequent studies found that they are also widely distributed on soils and do not necessarily exhibit host specificity 7,8,9 . P. oratosquillae isolated from animals and exhibits host specificity and from soil in Germany 21 ...
This study focused on isolating and identifying endophytic fungi from vegetable crops in Iraq. Samples from seven vegetable plants, including Anethum graveolens, Apium graveolens, Capsicum annuum, Malva parviflora, Mentha piperita, Petroselinum sativum, Portulaca oleracea, were collected from five central regions in Basrah, Iraq, (Abu Al-Khaseeb, Karmat Ali, AL-Zubair, Shatt Al-Arab and the Centre of Basrah). Samples, including mature leaves, stems and roots of vegetable sources, were collected and treated in the laboratory. Recovered endophytic fungi were purified and identified based on their macro and micromorphological features. Identification was validated by DNA sequencing and PCR amplification of ITS4 and ITS5 gene primers and molecular analysis. Phylogenetic examination indicated that three novel endophytic fungal species are documented in the Iraqi mycobiota for the first time, was isolated from vegetable plants in Basrah province related to the family Plectosphaerellaceae, including Gibellulopsis serrae, Plectosphaerella niemeijerarum, P. oratosquillae. Brief descriptions and photo panels are provided for the newly recorded species in this study. These findings are essential to understanding the endophytic fungal community within vegetable parts that can be used to manage and control plant disease and enhance productivity. Keywords: Ascomycota, Bsarah, endophytic fungi, Iraq, Plectosphaerellaceae.
... P. melonis is capable of limited colonization of the roots of some dicotyledonous plants of the families Asteraceae, Fabaceae, Malvaceae, Poaceae, and Solanaceae [7]. However, it is now known that P. melonis caused disease in basil, parsley, tomato, and pepper [37][38][39]. ...
Fungal diseases cause signifi cant damage to agriculture. Plectosphaerella melonis (syn. Acremonium cucurbitacearum and Nodulisporium melonis) is a pathogen of cultivated plant diseases in Spain, Italy, Japan, USA, Egypt, and Ukraine. This review discusses the main results of research related to this phytopathogen. By morphological and cultural features, P. melonis is a morphologically intermediate species between A. strictum and A. charticola, however, 5.8S-ITS regionbased phylogenetic analysis showed that P. melonis is a monophyletic taxon more closely related to Plectosphaerella than to other species of the genus Acremonium. The most susceptible plants are at the stage of germination; however, the development of the disease is manifested in the fruiting period. For a comprehensive assessment of virulence, real leaf area (RLA) of the first two leaves, lesion of hypocotyl (RH), root collar (RSR), primary (R1R) and secondary roots (R2R) are measured. P. melonis affects the root system, in particular the root collar and hypocotyl, and colonizes the epidermis and cortex of the root centrographically towards the stem. The range of host plants includes Cucurbitaceae, however, peppers, tomatoes, basil, and parsley are infected as well. Plants vary in susceptibility depending on the species and even variety. The pathogenic response of plants differs depending on the growing conditions (protected and open soil), the interaction between the pathogen and competing microorganisms, and other ecological and trophic relationships. The main means of control are the use of long-term crop rotations and the selection of resistant varieties. In Ukraine, a strain of the antagonist fungus Trichoderma viride was selected, which is an effective means for controlling P. melonis 502. The aim of our work was to establish the role of P. melonis in the development of diseases of cultivated plants.
... Moreover, this study allowed us, for the first time, to associate Plectosphaerella ramiseptata, as a soil-borne pathogen, with fennel plants, and to ascertain its ability to cause significant damages to seedlings consisting of root browning, leaf yellowing and plant growth reduction. Similar symptoms and the disease severity caused by P. ramiseptata have also been reported in tomato, pepper, basil and parsley [26,27]. ...
Fennel crop is a horticultural plant susceptible to several soil-borne fungal pathogens responsible for yield losses. The control of fungal diseases occurring on fennel crops is very difficult with conventional and/or integrated means; although several chemical fungicides are able to contain specific fungal diseases, they are not registered for fennel crops. The intensive use of some fungicides causes public concern over the environment and human health. The main aims of this study were to assess the ability of a strain of Streptomyces albidoflavus CARA17 to inhibit the growth of fungal soil-borne pathogens, and to protect fennel plants against severe fungal soil-borne pathogens such as Athelia rolfsii, Fusarium oxysporum, Plectosphaerella ramiseptata, Sclerotinia sclerotiorum and Verticillium dahliae. This study confirmed that the CARA17 strain has been able to inhibit the mycelium growth of pathogens in vitro conditions with significant inhibition degrees, where S. sclerotiorum resulted in being the most controlled. The strain CARA17 was also able to significantly protect the fennel seedlings against fungal soil-borne pathogens used in vivo conditions, where the treatment with an antagonist strain by dipping resulted in being more effective at limiting the disease severity of each fungal soil-borne pathogen. Moreover, any treatment with the CARA17 strain, carried out by dipping or after transplanting, produced benefits for the biomass of fennel seedlings, showing significant effects as a promoter of plant growth. Finally, the results obtained showed that CARA17 is a valid strain as a biocontrol agent (BCA) against relevant fungal soil-borne pathogens, although further studies are recommended to confirm these preliminary results. Finally, this study allowed for first time worldwide the association of Plectosphaerella ramiseptata with fennel plants as a severe pathogen.
... In recent times, many countries around the world recorded cases of a new disease of the Cucurbitaceae, the agent of which was P. melonis (syn. Acremonium cucurbitacearum) [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. In Ukraine, this disease was on cucumber plants in 2012 [14,19]. ...
In the last ten years, many countries around the world recorded a new disease of the Cucurbitaceae, the agent of which was P. melonis. The ability of P. melonis 502 to form intracellular mycelium in the epidermal and parenchymal tissues of roots was shown. Leading tissues (xylem and phloem) did not colonize, which indicates the impossibility of plant vessel clogging and shows the fungus’s biochemical effects on plants, which causes the process of pathogenesis. P. melonis 502 is able to develop in a wide range of pH values, while the pH-optimum is 8.5. P. melonis 502 is able to adjust the pH of the medium to the optimal value—8.5. We also showed that cellulase enzyme synthesis depends on pH. We studied the exo-, endo- and β-glucasidase activity of P. melonis 502 and found that the highest activity of cellulase enzymes was on a medium whose pH was 8.5. In the process, the total cellulolytic activity was 0.326 U mL−1, exoglucanase activity—0.539 U mL−1, endoglucanase activity—0.950 U mL−1 and β-glucosidase activity—0.795 U mL−1.
... Plectosphaerella spp. are known pathogens for a wide range of agricultural crops, including Cucurbitaceae (Carlucci et al., 2012;Raimondo and Carlucci, 2018a;2018b). ...
A fungus was isolated from diseased roots of Cucumis sativus grown in greenhouses. The morphological and cultural characteristics of the isolate allowed it to be classified as Plectosphaerella melonis. BLASTn analysis revealed 99% homology of the ITS sequence from the isolate with 14 Acremonium cucurbitacearum and P. melonis isolates, allowing attribution of the isolate to P. melonis (syn. A. cucurbitacearum). Koch’s hypothesis requirements were fulfilled for the isolate. Symptoms on host roots developed after 14 d of growing cucumber plants on infested soil. Plants of the cucumber variety Nizhynskyi 12 were very susceptible at the two leaf growth stage (2 weeks after sowing). Above-ground disease symptoms were absent after 14 d, even with severely diseased roots. This is the first report of P. melonis on C. sativus in Ukraine.
... It's reported that several Plectosphaerella spp. isolated from symptomless tomatoes and peppers can cause disease symptoms on tomato and pepper, and even basil and parsley when artificially inoculated [56,57]. Epichloë festucae is a well-known endophytic fungus of perennial ryegrass (Lolium perenne). ...
The Nanfengmiju (Citrus reticulata cv. Nanfengmiju), a high-quality local variety of mandarin, is one of the major fruit crops in Jiangxi Province, China. Citrus melanose and stem-end rot, two common fungal diseases of Nanfengmiju, are both caused by Diaporthe spp. (syn. Phomopsis spp.). Identification of the Diaporthe species is essential for epidemiological studies, quarantine measures, and management of diseases caused by these fungi. Melanose disease was observed on Nanfengmiju fruit in Jiangxi Province of China in 2016. Based on morphological characterization and multi-locus phylogenetic analyses, three out of 39 isolates from diseased samples were identified as D. passifloricola. Since these three isolates did not cause melanose on citrus fruit in the pathogenicity tests, they were presumed to be endophytic fungi present in the diseased tissues. However, our results indicate that D. passifloricola may persist as a symptom-less endophyte in the peel of citrus fruit, yet it may cause stem-end if it invades the stem end during fruit storage. To the best of our knowledge, this is the first report of D. passifloricola as the causal agent of the stem-end rot disease in Citrus reticulata cv. Nanfengmiju.
... According to the recent report, P. pauciseptata and P. ramiseptata are the most aggressive species causing leaf yellowing in plants (Raimondo and Carlucci 2018). Yellowing of leaves may be caused by manganese, zinc, or nitrogen deficiencies. ...
Pigeonpea (Cajanus cajan (L.) Millisp.) is an economically important grain legume of the tropical and subtropical region of the world and is one of the major inseparable dietary protein sources to the large mass of the Indian population. The diverse growing condition exposes the pigeonpea to different biotic and abiotic stresses during its life cycle. Pigeonpea get infected by various diseases nevertheless, only a few of them are of economic importance. After wilt (C.O: Fusarium udum) and sterility mosaic disease (C.O: Pigeonpea Sterility Mosaic Virus), Phytophthora stem blight (PSB) caused by Phytophthora drechsleri Tucker f. sp. cajani is the third most potentially important disease of pigeonpea in India. This disease is soilborne; the fungus survives as chlamydospores, oospores, and dormant mycelium in the soil and on infected plant parts. Moist cloudy weather with drizzling rain for about 6–8 hrs (RH = 85–95%) with temperatures around 25 °C favor disease development. The disease can be managed through agronomic interventions like early sowing, ridge planting, and summer ploughing of field to desiccate pathogen. The seed treatment and spraying of Ridomil MZ® at 3 g/kg seed and 2 g/liter of water, respectively, may give protection, but its efficacy is doubtful. Therefore, the development of resistant varieties would be an effective means to control the disease. This chapter describes the effect of P. drechsleri on pigeonpea and its productivity and will also describe the methods used in controlling the stem blight of pigeonpea.
... According to the recent report, P. pauciseptata and P. ramiseptata are the most aggressive species causing leaf yellowing in plants (Raimondo and Carlucci 2018). Yellowing of leaves may be caused by manganese, zinc, or nitrogen deficiencies. ...
Pigeon pea (Cajanus cajan L. Millsp.) is one of the leading pulses crops of India under the Leguminaceae family. It is grown as an annual and perennial crop under rainfed conditions, mostly in less fertile or marginal areas intercrop with cereals and oilseeds. The circumstances under which the crop is cultivated pose a major barrier for the crop, making it sensitive to abiotic and biotic stresses, and a key drawback in the maximum yield potential. Among the abiotic stresses, temperature, soil acidity, salinity, drought, waterlogging, etc. cause severe yield losses, and major biotic stresses include diseases like wilt, Phytophthora blight, Alternaria blight, etc. The crop is also susceptible to various parasitic nematodes, viz. Meloidogyne javanica, Heterodera cajani, Rotylenchus sp., etc. Pigeon pea has the specialty of biological nitrogen fixation (BNF) and efficiently establishes symbiosis with Bradyrhizobium spp. even though the crop is a promiscuous legume. This symbiosis provides more than 90% of nitrogen requirement for the crop depending on the conduciveness of the growing environment, variety of crop and type of soil. To be productive, the crop also requires neutral to slightly acidic soil conditions, and the potential yield is significantly reduced under extreme conditions of acidity, basicity or salinity, drought, etc. As the saying goes, “When the soil is deficient, the plants also are deficient and weakened, and they lose their defenses” (Charlotte Gerson). So, maintaining the soil health by supplying all the essential nutrients in the form of organic or inorganic manures is crucial for the crop to remain healthy and productive. Therefore, the efficient and improved practices of nutrient management like an application of cross-inoculants’ group-specific biofertilizers, enriched compost, liming of acid soils or gypsum application in alkaline soils can be practised for sustaining the soil health. Deep summer ploughing, soil solarization, biopesticides, etc. are some of the pathogen management practices for maintaining the health of the crop and, thus, reduction in yield losses.
