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Ascochyta blight severity (%) in seeds of desi chick- pea cultivar 'Myles' and kabuli chickpea cultivars 'CDC Yuma' or 'Sanford' at Saskatoon in 2003 and 2004, and at Kyle in 2004 in response to different fungicide application timing and frequency to control ascochyta blight.
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Field experiments were conducted during 2002–2004 at Saskatoon, Swift Current and Kyle, Saskatchewan to assess the effect of application frequency, timing and rotation of different fungicides on the suppression of ascochyta blight, and on yield and seed quality of chickpea cultivars ‘Myles’, ‘Sanford’ and ‘CDC Yuma’. Fungicides tested included chlo...
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Context 1
... few differences were observed among the remaining treatments in yield response and TSW, but treatments with applications at late flowering or podding tended to have larger seeds. Seed infection rates were very high in control plots (85%) and in plots of Treatments 2, 3 and 5 compared with Treatments 9, 10, 12 and 13 which had average infection rates of 10% and lower (Table 7). ...Citations
... The polycyclic nature of Ascochyta blight and the fact that its severity can increase quickly under the right environmental conditions mean that repeated fungicide applications may be necessary [96,99]. These repeated applications make fungicides a more costly method of control than others [100]. ...
Chickpea (Cicer arietinum L.), one of the most cultivated legumes worldwide, is crucial for the economy of several countries and a valuable source of nutrients. Yields may be severely affected by Ascochyta blight, a disease caused by the fungus Ascochyta rabiei. Molecular and pathological studies have not yet managed to establish its pathogenesis, since it is highly variable. Similarly, much remains to be elucidated about plant defense mechanisms against the pathogen. Further knowledge of these two aspects is fundamental for the development of tools and strategies to protect the crop. This review summarizes up-to-date information on the disease's pathogenesis, symptomatology, and geographical distribution, as well as on the environmental factors that favor infection, host defense mechanisms, and resistant chickpea genotypes. It also outlines existing practices for integrated blight management.
... Depending on the type and frequency of pulse crops in a rotation, the costs associated with fertilizers were reduced by up to 38%, and pesticide costs increased by up to 64% in comparison with the baseline (Table 2). It should be noted that rotations containing chickpea often had higher costs due to higher usage of pesticides against Ascochyta blight, a leaf/stem fungal disease caused by Ascochyta rabiei (Banniza et al. 2011). The results from the two 4-year rotation cycles had a trend of effects similar to that found in the first cycle (Khakbazan et al. 2020). ...
In the recent past, pulse crops have become increasingly important to agricultural producers as they contribute significantly to the economy. However, the research surrounding the economics of pulse crops is limited. This study determined the net returns and risks of 14 different rotations with various frequencies and sequences of pulse crops and quantified the long-term economic effects. An 8-year field experiment (two 4-year rotation cycles) was carried out at Swift Current, Saskatchewan, and Brooks, Alberta, Canada, during 2010–2019. The crops in the rotation included spring and durum wheat ( Triticum aestivum L.) (W), field pea ( Pisum sativum L.) (P), chickpea ( Cicer arietinum L.) (C), lentil ( Lens culinaris Medik) (L), and Oriental mustard ( Brassica juncea L.) (M). Net revenue was estimated and a simulation model was used to conduct the risk-return analysis. Net revenue was significantly different among the 14 rotations, where rotations with either high frequencies of lentil or diverse crops generated the highest net income. More diverse rotations such as P-M-L-W or L-C-P-W provided net income that were statistically comparable to the L-L-L-W rotation and were significantly greater than wheat monoculture systems. Risk analysis suggested that neutral or slightly risk averse producers may select rotations with higher frequencies of lentils, whereas more risk averse producers may prefer more diverse rotations. Inclusion of pulses in a rotation as preceding crops had a positive economic impact on the following non-pulse crops and reduced nitrogen cost by 37%, which can lead to a low carbon footprint. Long-term studies with comprehensive datasets are rare and here for the first time we had two full 4-year cycles of experimental data for 14 diverse rotations at three sites, enabling us to make sound conclusions—adopting diverse cropping rotations that include pulses, especially lentil, can reduce economic risks and improve farm profitability.
... International production of chickpea (Cicer arietinum L.), a grain legume, is under constant threat from the fungal disease Ascochyta blight (AB) caused by the pathogen Ascochyta rabiei (teleomorph: Didymella rabiei; Davidson and Kimber, 2007;Banniza et al., 2011;Kukreja et al., 2018;Benzohra et al., 2020). Ascochyta blight can cause significant yield losses and complete crop failure in susceptible cultivars in the absence of control measures (Chongo et al., 2003;Bretag et al., 2008). ...
... In the absence of adequate cultivar resistance, fungicides are required to control AB (Bretag et al., 2008). Previous research has focused on the use of fungicides, such as Chlorothalonil (Fungicide Group M5), Mancozeb (Group M3), Pyraclostrobin (Group 11), Azoxystrobin (Group 11), and Boscalid (Group 7;Chongo et al., 2003;Bretag et al., 2008;Banniza et al., 2011;Crutcher et al., 2022). However, in Australia, there have been several fungicide actives or mixes recently registered. ...
... The higher grain weights were also the plots with a lower AB disease severity, indicating that an increase in AB disease severity resulted in a decrease in grain weight. Previous studies have shown variable results on grain weight with some reporting no differences and others small differences (Iqbal et al., 2003;Banniza et al., 2011). In most experiments, a higher grain weight was associated with the cultivar Genesis 090 as compared to PBA Striker, which is expected with Genesis 090 a Kabuli type and PBA Striker a desi type (Hossain et al., 2010). ...
International production of chickpea is under constant threat from the fungal disease Ascochyta blight (Ascochyta rabiei). In Australia, there is limited cultivar resistance, and disease management is reliant on foliar applied fungicides. Several recently registered fungicides in Australia that combine active ingredients with different modes of actions, have been shown to have curative properties. In this study, in the presence of Ascochyta blight, disease severity, grain yield and quality were measured and the subsequent gross margin for growers calculated in seven field experiments conducted in Victoria (Australia) across three seasons. These experiments investigated the effects of: two cultivars with differing disease resistance (PBA Striker and Genesis 090), and several fungicide strategies for the control of Ascochyta blight. Fungicides that combine different modes of actions (Tebuconazole + Azoxystrobin, Bixafen + Prothioconazole and Fludioxonil + Pydiflumetofen) were applied before a rainfall event (preventative) or after the first signs of disease (post-infection). Older, single active fungicides compared included Captan, Chlorothalonil, and Propiconazole, all applied preventatively. Maximum disease severities ranged from 87% at Horsham and 94% at Curyo across three seasons with Nhill recording 87% during 2020. Demonstrating the benefit of cultivar resistance for Ascochyta blight management, grain yield losses were substantially lower in the partially resistant cultivar Genesis 090 (64%) compared to the susceptible cultivar PBA Striker (96%), at Curyo in 2020. The preventative fungicide strategies reduced grain yield losses from 96 and 64% to 51 and 15% for PBA Striker and Genesis 090, respectively, demonstrating the benefit of fungicides in Ascochyta blight management. Across seasons and environments, a comparison between fungicides applied preventatively or post-infection highlighted both were both profitable ($23–$1,095/ha), except when dry conditions limited grain yield to less than 0.6 t/ha. The post infection timing had greater yield losses in sites/seasons with higher rainfall, but with dual active ingredient fungicides and partially resistant cultivars this timing could allow a reduction in the number of fungicide applications, thus improving profitability. These experiments highlighted the importance of controlling Ascochyta blight through cultivar resistance and fungicides to improve grain yields, grain quality, and grower profitability.
... Several fungicides have been reported effective in the world for the control of ascochyta blight but their repeated applications are uneconomical where chickpea yield is low (3,7). Antracol, chlorothalonil, maneb, zineb, penconazole, propiconazole, thiabendazole, sulphur based fungicides and captan have been reported effective to avoid secondary spread of ascochyta blight (3). ...
Two fungicides, Aliette and ThiovitJet @ 0.15%, containing Aluminum tris (O-ethyl phosphonate) and sulphur compounds, respectively; two plant extracts, Melia azedarach and Azadirachta indica @ 8% and one biocontrol agent, Trichoderma harzianum @ 10 7 conidia ml-1 were investigated against ascochyta blight of chickpea under field conditions. Treatments were evaluated on three varieties susceptible to chickpea blight. Field trial revealed that Aliette and ThiovitJet significantly decreased disease severity to 17 and 23% respectively, followed by M. azedarach and A. indica which decreased severity to 50 and 56% respectively, compared to control with 75% disease severity. T. harzianum, with a severity of 63%, was significantly less effective than fungicides and both plant extracts in controlling blight disease. The current research revealed that systemic and sulphur containing fungicides, both plant extracts and the biocontrol agent have the potential to control ascochyta blight of chickpea.
... Timely use of fungicides, such as chlorothalonil, pyraclostrobin, and boscalid, are necessary to suppress foliar diseases in some crops [139]. While fungicides are meant to target specific fungal pathogens, they impact non-target organisms, and may alter soil microbial community structure [131]. ...
The global demands for various grains, including durum wheat (Triticum turgidum L. subsp. durum (Desf.) Husn.), are expected to increase substantially in the coming years, due to the ever-growing human population’s needs for food, feed, and fuel. Thus, providing consistent or increased durum grain to the world market is one of the priorities for policy-makers, researchers, and farmers. What are the major achievements in agronomic advancement for durum wheat cultivation in recent decades? How might the current cropping systems be improved to increase crop yield and quality and improve resource use efficiencies while minimizing input costs and decreasing negative impact on the environment? Canada is one of the major durum wheat producers in the world, as Canada contributes about 50% to global trade of durum grain. Canada’s research achievements in durum wheat might serve as a guide for advancing the cultivation of the crop in other regions/countries on the planet. This review summarizes the major Canadian research findings in the aspects of durum wheat agronomics during the period 2001 to 2017 years. It highlights the main advancements in seeding and tillage, crop rotation and diversification, and use of pulse-induced microbiomes to improve soil health and feedback mechanisms. The genetic gain and breeding for resistance against abiotic and biotic stresses are discussed. Finally, we identified the main constraints and suggested some near-term research priorities. The research findings highlighted in this review will be of use for other areas on the planet to increase durum wheat productivity, improve soil fertility and health, and enhance long-term sustainability.
... Timely use of fungicides, such as chlorothalonil, pyraclostrobin, and boscalid, are necessary to suppress foliar diseases in some crops [139]. While fungicides are meant to target specific fungal pathogens, they impact non-target organisms, and may alter soil microbial community structure [131]. ...
The global demands for various grains including durum wheat (Triticum durum Desf.) are expected to increase substantially in the coming years due to ever-growing human population’s needs for food, feed and fuel. Thus, providing consistent or increased durum grain to the world market is one of the priorities for policy-makers, researchers, and farmers. What are the major achievements in agronomic advancement for durum wheat cultivation in recent decades? How might the current cropping systems be improved to increase crop yield and quality and improve resource use efficiencies while minimizing input costs and decreasing negative impact on the environment? Canada is one of the major durum wheat producers in the world, as Canada contributes about 50% to global trade of durum grain. Canada’s research achievements in durum wheat might serve as a guide for advancing the cultivation of the crop in other regions/countries on the planet. This review summarizes the major Canadian research findings in the aspects of durum wheat agronomics during the period 2001 to 2017 years. It highlights the main advancements in seeding and tillage, crop rotation and diversification, and use of pulse-induced microbiomes to improve soil health and feedback mechanism. The genetic gain and breeding for resistance against abiotic and biotic stresses are discussed. Finally, we identified main constraints and suggested some near-term research priorities. The research findings highlighted in this review will be of use for other areas on the planet to increase durum wheat productivity, improve soil fertility and health, and enhance long-term sustainability.
... This concern is elevated by the site-specific mode of action (MOA) of the fungicides, the polycyclic nature of the disease, airborne spores of the AB pathogens, and of the option of sexual reproduction for most species, allowing rapid mutation and allow inheritance by offspring. The polycyclic nature of the disease predisposes growers to repeat fungicide applications as disease severity can increase rapidly when the weather is favorable, particularly with AB of chickpeas (Banniza et al., 2011;Lonergan et al., 2015;Fungicide Resistance Action Committee, 2016). ...
Ascochyta blight (AB) of pulse crops (chickpea, field pea, and lentils) causes yield loss in Montana, where 1.2 million acres was planted to pulses in 2016. Pyraclostrobin and azoxystrobin, quinone outside inhibitor (QoI) fungicides, have been the choice of farmers for the management of AB in pulses. However, a G143A mutation in the cytochrome b gene has been reported to confer resistance to QoI fungicides. A total of 990 isolates of AB-causing fungi were isolated and screened for QoI resistance. Out of these, 10% were isolated from chickpea, 81% were isolated from field peas, and 9% isolated from lentil. These were from a survey of grower’s fields and seed lots (chickpea = 17, field pea = 131, and lentil = 21) from 23 counties in Montana sent to the Regional Pulse Crop Diagnostic Laboratory, Bozeman, MT, United States for testing. Fungicide-resistant Didymella rabiei isolates were found in one chickpea seed lot each sent from Daniels, McCone and Valley Counties, MT, from seed produced in 2015 and 2016. Multiple alignment analysis of amino acid sequences showed a missense mutation that replaced the codon for amino acid 143 from GGT to GCT, introducing an amino acid change from glycine to alanine (G143A), which is reported to be associated with QoI resistance. Under greenhouse conditions, disease severity was significantly higher on pyraclostrobin-treated chickpea plants inoculated with QoI-resistant isolates of D. rabiei than sensitive isolates (p-value = 0.001). This indicates that where resistant isolates are located, fungicide failures may be observed in the field. D. rabiei-specific polymerase chain reaction primer sets and hydrolysis probes were developed to efficiently discriminate QoI- sensitive and - resistant isolates.
... Some efforts were made to develop faba bean genotypes with good levels of pod resistance, but many breeding programs did not use this trait in their selection program (Lockwood et al., 1985;Sillero et al., 2001). The most effective fungicides to manage Ascochyta blight were chlorothalonil and azoxystrobin which are also known to be used in controlling Ascochyta blights on chickpea and lentil (Banniza et al., 2012). We conclude that there will be limited variations among protective and curative fungicides in effectiveness against Ascochyta blight when disease incidence is very low. ...
... However, improved varieties are only moderately resistant to the pathogen due to availability of only partial resistance among the cultivated chickpea germplasm (Taran et al., 2013). Consequently, mostly foliar and some systemic fungicides are used to combat the menace (Shtienberg et al., 2005Shtienberg et al., , 2006 Ahmed et al., 2008; Banniza et al., 2011 ). However, this practice increases the production cost due to multiple applications of the fungicides that is a typical requirement of this disease (Acikgoz et al., 1994). ...
Ascochyta rabiei (Pass.) Lab. causes blight that is a major constraint in chickpea production worldwide including Pakistan. Disease is generally controlled by repeated applications of foliar fungicides that cause environmental pollution and also responsible for health hazards. The present study was carried out to investigate the antifungal potential of different organic solvent fractions of methanolic fruit extract of Melia azedarach L. against A. rabiei (Pass.) Lab. Methanolic fruit extract of this tree was partitioned with n-hexane, chloroform, ethyl acetate and n-butanol. After evaporation of solvents in a rotary evaporator, different concentrations of the crud organic fraction were prepared and evaluated against the target fungal pathogen. All the concentrations of organic solvent fractions significantly reduced the fungal biomass over corresponding control treatments. There was 43-87%, 75-94%, 69-95%, 38-89% and 63-94% reduction in fungal biomass due to different concentrations of n-hexane, chloroform, ethyl acetate, n-butanol and aqueous fraction of methanolic fruit extract of M. azedarach, respectively. The present study concludes that all these fractions of methanolic fruit extract of M. azedarach possess substantial antifungal potential against A. rabiei. These fractions and their purified compounds may be used as alternatives to synthetic fungicides for the management of A. rabiei.
Pulse crops, such as chickpea (Cicer arietinum L.), serve as excellent food sources that provide proteins and minerals to humans and livestock. Additionally, pulses are important sources of soil nitrogen in rotational cropping systems. However, pulse production is limited by several biotic and abiotic stress factors. One such disease is Ascochyta blight (Ascochyta rabiei) in chickpea. To minimize the impact of Ascochyta blight, timely information on disease outbreak and epidemics is essential for implementing disease control methods. Thus, in this study, the feasibility of monitoring Ascochyta blight disease severity in chickpea using remote sensing techniques was evaluated. Disease severity was monitored using an unmanned aircraft system integrated with different types of sensors (3-band multispectral, 5-band multispectral, and thermal cameras). Results indicated that different flight altitudes (60 m and 90 m above ground level) that lead to different image resolutions did not influence disease detection efficiency, especially with the 3-band camera. Selected image features, including canopy area, percentage of canopy area, and vegetation indices (e.g., green normalized difference vegetation index) from multispectral cameras, and mean canopy temperature from the thermal camera, were significantly correlated with yield and visual ratings of disease severity. Moreover, hyperspectral sensing was found to be useful in predicting disease severity. In summary, this study demonstrated that disease severity of Ascochyta blight in chickpea can be monitored using remote sensing methods under active field conditions. With timely and accurate disease severity information from high-throughput phenotyping technologies, the effects of Ascochyta blight on chickpea yield and quality can be minimized with timely application of proper management techniques.
