Effective Genes for Resistance to Wheat Yellow Rust and Virulence of Puccinia striiformis f. sp. tritici in Egypt

Document Type : Original Article

Author

Wheat Diseases Department, Plant Pathology Research Institute, ARC, Egypt

Abstract

Yellow (stripe) rust of wheat (Triticum aestivum L.), caused by Puccinia striiformis f. sp. tritici, is a serious problem of wheat production in many parts of the world including Egypt. Virulence patterns of wheat stripe rust were studied under the field conditions in four growing seasons (2013 to 2017) at Sakha Agriculture Research Station by planting international stripe rust trap nursery of differentials sets, isogenic lines and some Egyptian genotypes. The results revealed that stripe rust resistance genes Yr2+, Yr5, Yr10, Yr15 and YrND were effective, while Yr18 and Yr29 were partially effective during study periods showing moderate susceptibility. Genes Yr2, Yr6, Yr7, Yr8, Yr9, Yr17, Yr27, Yr32, and gene combinations Yr27+Yr18 (Opata 85)  were found susceptible. Chinese 166 with resistance gene Yr1 has shown susceptible reaction in 2014/2015 growing season. Among the twenty commercial genotypes; Misr 1, Misr 3, Gemmeiza 7, and Sakha 95 were resistant. On other hand, some of the most important commercial genotypes i.e. Sids 12, Giza 168, Misr 2 and Sakha 61, known as resistant to the previously characterized races of yellow rust in Egypt became susceptible in this study. The genes found effective against yellow rust under natural conditions could be deployed singly or in combination to develop yellow stripe resistant and high yielding wheat varieties in Egypt.

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