Journal de pathologie végétale et de microbiologie

Abstrait

Population Genetic Structure among Iranian Isolates of Fusarium verticillioides

Hassan Momeni and Fahimeh Nazari

The genetic structure among Iranian populations of Fusarium verticillioides from the main corn growing areas of five provinces including Ardabil, Fars, Mazandaran, Khorasan, and Khuzestan were evaluated using VCG, RAPD and rep-PCR. Sixty-one isolates of F. verticillioides were placed in 14 Vegetative Compatibility Groups and 19 haplotypes. VCG3 with 14 members (23% of all isolates) was the most frequent VCG. RAPD-PCR and rep-PCR generated multiple distinct products demonstrated considerable variability among the isolates of different VCGs. Haplotype 1(HP1) had the highest frequency (0.57) in the population and was present in isolates from the majority of the locations in this study. All molecular phenotypes were distributed randomly across the various locations. Although there are some consistent between geographical origin of the isolates and their genetic similarity but VCG groups were distributed among different geographical locations and there was no correlation between geographical distribution and VCG groups. Gene diversity was 0.2909 and populations of F. verticillioides were placed in five distinct groups based on geographical origin. The highest genetic distance observed between Fars and Khuzestan (0.1801) and the smallest genetic distance was obtained between Ardabil and Khuzestan (0.0589). Analysis of molecular variance (AMOVA) showed a significant difference among populations of F. verticillioides. According to our results PhiPT was equal to 0.176 (p<= 0.001) and 82% of genetic variance occurred within populations and only 18% was found among populations. Moghan in Ardabil province is the main site for seed producing in Iran and the seeds that are produced there are distributed all over the country. In this study isolates of Moghan were located besides the isolates from other regions in different clusters. So it is presumed that the infected seeds from Moghan can be a major source for the spreading of the disease through all corn growing areas in Iran.