مشخصات پژوهش

Abstract Assessment of eighty Fusarium proliferatum isolates obtained from maize, rice, sugarcane and onion using AFLP molecular marker separated the isolates into four distinct clusters according to their host’s. Isolates recovered from rice clustered in a distinct group. Isolates from sugarcane grouped in two distinct groups and isolates recovered from maize and onion clustered in a unit group. As well, all studied F. proliferatum isolates originated from different hosts expressed pathogenicity to maize ears. However, different levels of pathogenicity were observed among and within of different host populations. Duncan’s test analysis showed isolates from maize, sugarcane and onion belonged to group A and rice isolates placed in group B. Moreover, a correlation was observed between AFLP clustering and pathogenicity of the maize, sugarcane and onion isolates compare to isolates coming from rice. All of the isolates were examined for PCR based identification of mating type idiomorphs and determination of sexual fertility status. Among 142 isolates of F. proliferatum, 72 isolates (50.7%) were identified as MAT-1 and 70 isolates (49.2%) were belonged to MAT-2. The presence of both mating type idiomorphs with favorable frequency among isolates recovered from different hosts of F. proliferatum, shows that there is a potential for sexual reproduction within these populations. On the other hand, female fertility examination for 40 randomly selected field isolates including 10 isolates of each host populations showed all the isolates are female-sterile. Finally, we concluded that the genetic variation within F. proliferatum populations in Iran is possibly a result of vegetative compatibility, parasexual cycle, various cultivars of the hosts and high amount of migration to the populations as well as sexual reproduction.