Genetic diversity of Fusarium oxysporum f. sp. ciceris isolates affecting chickpea in Syria

Fusarium wilt (Fusarium oxysporum f.sp. ciceris) is the most important soil-borne disease of chickpea in Syria. Seventy isolates of the wilt pathogen were isolated from diseased plant samples collected from farmers' fields and research centers in Syria, and a research station in Lebanon, were studied for their genetic diversity using random amplification of polymorphic DNA (RAPD), simple sequence repeat (SSR) markers and sequence characterized amplified region (SCAR) molecular markers. High genetic diversity within populations and low among populations was observed. The cluster analyses grouped the isolates into seven clusters and the STRUCTURE analyses showed three populations. Using race-specific markers, four races (0, 1B/C, 5 and 6) were identified and 12 isolates were not designated to any of the known races. The dominant races were 0 and 1B/C in the pathogen population where the former was dominant in both spring- and winter-planted chickpea crops. This study showed that ICARDA breeding lines are being evaluated against mixed races and populations. Hence elite chickpea lines distributed to national partners carry resistance to many races and populations prevalent in the Mediterranean regions.