Study of genetic diversity of Fusarium verticillioides isolates the causal agent of crown and root rot in rice in ilam province using SSR marker

Root rot caused by Fusarium verticillioides is one of the most important rice diseases in Ilam. In order to determine genetic diversity، 56 samples were collected from rice paddies of different regions in Ilam province. Molecular test was carried out with a set of five pairs of SSR primers after purification and identification of isolates. The SSR primers amplified a total 26 alleles. The average of allele number was 5. 2 per each primer. 40 alleles were observed in 5H08 and 5H09 loci as highest allele numbers and 24 alleles were observed in 5H12 locus as lowest. The polymorphism index content value was the highest in primers 5H07 with 0. 37 and the lowest in primers 4H18 with 0. 14. The average of PIC was 0. 25 in all primers. Cluster analysis using Neighbor joining method and Jaccard''s coefficient، divided the isolates into 10 groups at 8% similarity level. Result of AMOVA showed 98% of genetic diversity was in relation to isolates and only 2% was in related to different geographical regions. Therefore there is the high genetic similarity between isolates from different geographic regions. High genetic similarity can be attributed to emigration of gene or genotype as a result of various factors.