Population studies of causative agent of wheat yellow rust in the Northwest Russia

All Russian Institute of Plant Protection, Laboratory of Mycology and Phytopathology, 196608 Saint Petersburg, Russia

^* Corresponding author: eshaydayuk@bk.ru

Abstract

Wheat yellow rust (causative agent Puccinia striiformis West.) is a widespread disease of common wheat in the North-West Russia. A comparative analysis of P. striiformis populations, collected in the Leningrad region in 2019 on wheat and triticale, by virulence and racial composition was carried out for the first time. Virulence and racial composition of P. striiformis were studied using international and European sets of differentiating varieties and isogenic lines of “Avocet” with 20 Yr genes. A total of 55 single-pustule isolates of P. striiformis were studied, including 31 from common wheat, 10 from durum wheat and 14 from triticale. Using differentiating varieties, 2 races (111E247, 110E247) were identified among isolates from common wheat, 3 races from durum wheat (111E213, 111E231, 111E247), and 5 races from triticale (111E247, 78E209, 79E209, 111E231, 78E215). Using “Avocet” isogenic Yr lines, all isolates were avirulent to lines with the Yr5, Yr10, Yr11, Yr12, Yr15, Yr24, Yr26 genes and virulent to Yr6, Yr7, Yr8, Yr9, Yr18, YrSp, YrJr(18), YrAS genes. Isolates virulent to Yr17 were revealed on triticale; avirulent to YrSk (27) – on durum wheat. and avirulent to YrAR – on triticale. Highly effective Yr genes can be recommended for wheat resistance breeding to to yellow rust.