Determination of pathotype group, mating type and disease severity of ascochyta blight in chickpea in the Black Sea Region

Disease severity, pathogenic characterisation and mating type analyses of Ascochyta blight agent, Didymella rabiei (Kovachevski) von Arx [anamorph: Ascochyta rabiei (Passerini) Labrousse], which is one of the main problem restricting chickpea (Cicer sp.) yield in the Blacksea ragion of Turkey, were studied. Survey studies were conducted during July 2014 in the Blacksea region. Results revealed the highest disease severity in the Samsun province (58,86%) and the lowest disease severity in the Giresun province (0,75%). A total of 176 D. rabiei isolates were recovered from different locations and among them, 114 isolates were used in mating type analyses. According to the data obtained, the number of Mat 1.1 and Mat 1.2 were 56 and 58, respectively. The ratio of Mat 1.1/ Mat 1.2 did not deviate from Mendel's 1:1 ratio. The isolates used for pathotyping analyses in which selected according to mating type distribution and field disease severity were 1.72%, 10.34%, 27.60%, 43.10% and 7.24% for Pathotype-1, Pathotype-2, Pathotype-3, Pathotype-4 and low virulence, respectively. The Pathotype-4 detected in the Blacksea region is the first report revealed through this study.