Mating type distribution using a multiplex PCR mating assay and fertility status inDidymella rabieiin chickpea-growing areas in Iran

Ascochyta blight, caused by Ascochyta rabiei is the most destructive disease of aerial parts of chickpea (Cicer arietinum L.) worldwide. Forty isolates of A. rabiei representing eight geographical regions, were collected from the west and south western Iran, and analysed for mating type distribution and fertility. A multiplex PCR assay using specific primers designed to amplify partial regions of the MAT1–1 and MAT1–2 idiomorphs was used to facilitate population analysis. Didymella rabiei populations were dominated by MAT1–1 mating type. The fertility status of isolates was determined using controlled crosses in vitro, pairing each isolate with compatible standard testers (USDA-AR-20 and USDA-AR21). Out of the 40 tested isolates, 38 isolates (95%) were MAT1–1 and two isolates (5%) were MAT1–2. Both mating types were present in Gachsaran and Jalian Populations, where Chi-square tests showed the proportions of each mating type were significantly different from 1:1 ratio. The predominance of one mating type ...