نقش برخی از عوامل مؤثر بر جمعیت اپی‌فیت باکتری Xanthomonas axonopodis pv. phaseoli در همه‌گیری بیماری سوختگی معمولی لوبیا

To understand the role of relative humidity rate, host genotype, inoculation method and growth stage in epidemiology of bean common blight, two greenhouse experiments were carried out monitoring epiphytic population size of Xanthomonas axonopodis pv. phaseoli (Xap) and disease severity. The result showed significant differences among genotypes, inoculation methods and growth stages for epiphytic population size and sam effects except genotypes for disease severity. The epiphytic population size was significantly higher on spray inoculated Khomein cultivar of bean during flowering (R6). However, the relative humidity rates did not significantly affect population dynamics of epiphytic Xap and the disease severity. Two field experiments were also carried out to determine the effects of irrigation systems (furrow irrigation and overhead sprinkler irrigation), inoculation method, growth stage and their interactions on epiphytic population size of Xap and disease severity. The result showed that the epiphytic population size and disease severity were higher on spray inoculated plants irrigated with overhead sprinkler system during pods filling (R8). In this study, a significant positive correlation was found between epiphytic population size of Xap and bean common bacterial blight severity.