Identification of wheat samples for resistance to toxins of Pyrenophora tritici-repentis (Ptr)

Pyrenophora tritici-repentis (Ptr) is a causal agent of tan spot in wheat Kazakhstan, as it has been around the world. The pathogen produces host-specific toxins which interact with host sensitivity loci. aim this study was 1) to identify whether selected Kazakhstani isolates P. tritici- repentis possessed Ptr toxin genes ToxA and/or ToxB and 2) varieties resistant HST ToxB. As result analysis frequency occurrence PTR races, found that races 7 (25%) 8 (41.6%) dominate from southern race 4 (62.5%) prevails northern Kazakhstan. Twenty single spore collected wheat-growing areas South North Kazakhstan representing population were characterized for presence genes, using two gene specific primers. Eight (40%) positive gene, (10%) gene. not previously our country, but results show appearance south Eleven (64.7%) identified molecular markers linked tsn1 insensitive ToxA. genotypes are recommended use breeding resistance spot.