List of Articles Ascochyta blight

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  1 - The antifungal effect of several essential oils on Ascochyta rabiei, the causal agent of chickpea Ascochyta blight in vitro and greenhouse conditions
  Mohammad Samari Mojdeh Maleki dariush shahriari Neda Kheradpir
  One of the greatest biotic stress reducing potential yield in chickpea is Ascochyta blight caused by Ascochyta rabiei Pass. (Labr.) which is distributed worldwide. Due to its severity and to decreasing the environmental biological impact of chemical control, research on More

  One of the greatest biotic stress reducing potential yield in chickpea is Ascochyta blight caused by Ascochyta rabiei Pass. (Labr.) which is distributed worldwide. Due to its severity and to decreasing the environmental biological impact of chemical control, research on natural compounds like plant essential oils would be a helpful step in the disease management. In this study, the antifungal efficacy of essential oil of eight plants including thyme, savory, pennyroyal, mint, tarragon, fennel, cumin and ajwain at 5 concentrations in 3 replications under complete random design was evaluated. Characteristics like mycelial growth inhibition (MGI), inhibitory minimum concentration (IMC) and speed of colony growth after treatment were studied under laboratory condition. Pathogenicity index was studied under greenhouse condition by the selected plants through laboratory tests in comparison with the fungicide Rovral-TS and intact and infected controls. Result showed that at greenhouse, thyme and fennel showed the most inhibitory index in comparison with the rest six plants. Fennel showed the most effective MGI against Ascochyta blight at laboratory. The result of the present study show that thyme and fennel would be great options to be considered in the integrated management programs of chickpea Ascochyta blight. Manuscript profile
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  2 - Pathogenic variability of Didymella rabiei, the agent of ascochyta blight of chickpea in Kermanshah province
  Elahe Paymard Mohammad Torabi Dariush Shahriari
  Blight disease of chickpea caused by Ascochyta rabiei (Pass.) Lab.is one of the most important chickpea diseases in the world and Iran, which causes huge damages to chickpea farm in the suitable climatic conditions. Study of genetic diversity and various races exist in More

  Blight disease of chickpea caused by Ascochyta rabiei (Pass.) Lab.is one of the most important chickpea diseases in the world and Iran, which causes huge damages to chickpea farm in the suitable climatic conditions. Study of genetic diversity and various races exist in the different regions would be necessary for resistant cultivars development. In this research physiological races of 28 isolates of A. rabiei which were collected and purified from five region of Kermanshah province during 2012-2013 were determined using seven differential chickpea cultivars (ILC-202, ILC-1929, ILC-5928, ICC-3996, ILC-194, ILC-1929 and ILC-72). All isolates were classified in six physiological races. Among the all isolates, seven isolates (25%) belonged to race 1, Five isolates (17.8%) belonged to race 2, Seven isolates (25%) belonged to race 3, Four isolates (14.4%) belonged to race 4, two isolates (7.2%) belonged to race 5 and three isolates (10.6%) belonged to race 6. Races 1, 2, 3 and 4 with 23 isolates (82.1%) were occurred in all areas of the province while race 6 with high virulence was detected only in one area (Sararood). Investigation of the morphological traits of isolates on CSA (Chickpea sucrose Agar), showed differences in view of diameter, color and form of colony, pycnidium density and pycnidium size among the isolates, but there was not any difference in term of pycnidiospore size.   Manuscript profile
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  3 - Identification of Pathotypes in Ascochyta rabiei (Pass.) Labr., the agent of Ascochyta blight in chickpea in provinces of Kermanshah and Ilam and resistance evaluation of chickpea cultivars and lines against disease
  Shahrzad Khalatbari Dariush Shahriari Mojdeh Maleki
  Ascochyta blight caused by Ascochyta rabiei Pass. (Labr.)is one of the greatest disease in chickpeathat cause total yield loss if the environmental conditions are favorable. The use of resistant cultivars is the most effective management strategy for ascochyta blight in More

  Ascochyta blight caused by Ascochyta rabiei Pass. (Labr.)is one of the greatest disease in chickpeathat cause total yield loss if the environmental conditions are favorable. The use of resistant cultivars is the most effective management strategy for ascochyta blight in chickpea. In our study, 24 different isolates of A. rabiei from plants infected by this disease were obtained in provinces of Kermanshah and Ilam and then isolated and purified. For evaluation of the morphological characteristics, discs of colonies of fungal isolates were sown in PDA, CDA, CSA and WA media. For pathotypes identification, the isolates were sporulated on differential chickpea cultivars by concentrations with 106 spores per ml. 41 genotypes and chickpea cultivars inoculated by three A. rabiei pathotype like pathogenicity method in greenhouse. The severity of the disease index is noted from 1 to 9, according to the scale of Jan and Wiese and 12 days later when the intensity of symptoms reached to 90 percent on susceptible cultivar. The results of our study revealed morphological and genetic diversity of the fungus. In this survey, three pathotypes identified in different districts of Kermanshah and Ilam, respectively. Pathotypes 1 of 13 of total isolates was the most widely distributed then, pathotype II with 6 isolates and pathotype III with 5 isolates were the least ones. The response of 41 cultivars against three pathotype of A. rabiei, Adel, Azad cultivar that have just been released by the Agricultural Research Institute of Dryland over the past few years together with advanced line of Flip 03-109C against the pathotype III showed moderately resistant response while other lines and cultivars were susceptible or highly susceptible. In total, lines of Flip51-87C, Flip03-119C, Flip04-13C and Flip04-10C showed resistant or moderately resistant response for pathotypes. Manuscript profile
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  4 - Studies on pathogenicity differences of the fungus isolates of Ascochyta fabae Speg., the causal agent of Ascochyta blight and evaluating the resistance of the faba bean cultivars to disease
  Atefeh Shiravi Dariush Shahriari Fatemeh Shaikh
  Ascochyta blight caused by the fungus Ascochyta fabae Speg., is known as one of the most destructive diseases of faba bean worldwide. Yield losses due to attacks by this fungus can reach more than 90% when cultivars are sown under cool and wet conditions. Disease Contro More

  Ascochyta blight caused by the fungus Ascochyta fabae Speg., is known as one of the most destructive diseases of faba bean worldwide. Yield losses due to attacks by this fungus can reach more than 90% when cultivars are sown under cool and wet conditions. Disease Control by using crop rotation, clean seed and chemical treatments cannot be fully effective. Therefore, using the resistant cultivars as a reduction factor of the disease severity and infection type is very important for disease control. At first, different fungal isolates were collected from northern areas of Iran, purification and pathogenicity was carried out on the susceptible cultivar of Barkat with spore suspension by concentrations of 106 spores per ml on leaves in the greenhouse condition. For identifying isolates virulence, the fungus inoculated was done on the susceptible cultivar of Barkat like pathogenicity test method. Disease severity index implemented when the symptoms appeared and was carried out 15 days after sporulating by Sillero and Rubiales method. The responses of 14 faba bean genotypes and cultivars were evaluated to disease in randomized complete block design in field conditions with three replications. Among total sampling of different regions, 10 pure isolates of A. fabae with high virulence totally obtained which indicated a high variability in Mazandaran and Golestan provinces. The results of resistance evaluation of faba bean genotypes and cultivars in field conditions revealed the resistance response of genotypes of G-faba-67, G-faba-95, G-faba-100, G-faba-133 and Zereshki cultivar along with disease severity index 25.66 to 40.33 percent and the other cultivars (6 genotypes and 3 cultivars) equal to 64% of all tested cultivars susceptible and genotypes showed a susceptible or highly susceptible response. Manuscript profile