Pathotypes of Pyrenophora teres on barley in Turkey

Abstract

Net blotch foliar diseases of barley are important in Turkey, lowering grain yields and quality. There are two forms, the spot form (caused by Pyrenophora teres f. maculata (Ptm)) and the net form (caused by P. teres f. teres (Ptt)). To determine the pathotypes of Ptt and Ptm in Turkey, surveys were carried out during 2012, 2013 and 2015. Pyrenophora teres samples were collected from 34 provinces of Turkey. From these samples, 258 Ptm and 167 Ptt single conidium isolates were obtained. Pathotypes of 50 P. teres f. maculata and 40 P. teres f. teres isolates were assessed by inoculating onto a differential set of 25 barley genotypes. Twenty six Ptm pathotypes and 24 Ptt pathotypes were identified, and significant pathogenic variation was found among the isolates. Barley breeding programmes in Turkey should consider the pathotypes identified for incorporation of net blotch resistance. Continuous virulence monitoring for the P. teres population should be carried out to inform resistance breeding priorities.