blast disease development in some iranian and afghan rice varieties in guilan province environmental conditions

Blast disease development caused by the fungus pyricularia oryzae cavara was determined in leaf and panicle stages in some iranian and afghan rice varieties. for this purpose, hashemi, kazemi, anam, sadri, surkha, niloofar, surkha long, shiroudi, koli and shola varieties were grown at the experimental field of the university of guilan in 2021 and 2022 growth seasons as a randomized complete block design. as the first disease symptoms were observed in experimental plots, disease severity was assessed and continued at specific intervals until harvest time. the results indicated a significant difference between varieties in disease development at the leaf and panicle stages. the initial severity, progression over time and final severity of leaf blast varied among the studied varieties. in both years of the study, the niloofar variety showed the highest susceptibility to leaf blast (69.16% in 2022). surkha, sadri and shola varieties showed high susceptibility as 31.78%, 24.75% and 17.27 and hashemi and kazemi had less susceptibility as 6.68% and 5.95%, respectively. there was no significant increase in the severity of leaf blast in the surkha long, anam, koli and shiroudi. regarding panicle blast in both years, niloofar variety showed the highest susceptibility based on the panicle blast severity (97.46%) and then, surkha long and kazemi varieties had the highest severity of panicle infection (18.86% and 17.6%, respectively). shola, sadri, surkha, hashemi, and anam varieties were less susceptible. shiroudi and koli varieties were the most resistant to the panicle blast infection.

blast disease development in some iranian and afghan rice varieties in guilan province environmental conditions

blast disease development caused by the fungus pyricularia oryzae cavara was determined in leaf and panicle stages in some iranian and afghan rice varieties. for this purpose, hashemi, kazemi, anam, sadri, surkha, niloofar, surkha long, shiroudi, koli and shola varieties were grown at the experimental field of the university of guilan in 2021 and 2022 growth seasons as a randomized complete block design. as the first disease symptoms were observed in experimental plots, disease severity was assessed and continued at specific intervals until harvest time. the results indicated a significant difference between varieties in disease development at the leaf and panicle stages. the initial severity, progression over time and final severity of leaf blast varied among the studied varieties. in both years of the study, the niloofar variety showed the highest susceptibility to leaf blast (69.16% in 2022). surkha, sadri and shola varieties showed high susceptibility as 31.78%, 24.75% and 17.27 and hashemi and kazemi had less susceptibility as 6.68% and 5.95%, respectively. there was no significant increase in the severity of leaf blast in the surkha long, anam, koli and shiroudi. regarding panicle blast in both years, niloofar variety showed the highest susceptibility based on the panicle blast severity (97.46%) and then, surkha long and kazemi varieties had the highest severity of panicle infection (18.86% and 17.6%, respectively). shola, sadri, surkha, hashemi, and anam varieties were less susceptible. shiroudi and koli varieties were the most resistant to the panicle blast infection.