Incorporating Yellow Rust Resistance Genes Yr8, 15, 27, 34 And 57 In Some Susceptible Egyptian Bread Wheat Cultivars

Abstract

Five yellow rust monogenic lines were used as donors of the genes Yr8 , Yr15 , Yr27 , Yr34 and YR57 to the Egyptian bread wheat cultivars Misr-1, Misr-2, Gemmeiza-11 and Shandaweel-1 through conventional crossing during 2019/2020 to 2021/2022 seasons at Sakha Agricultural Research Station. The monogenic lines were evaluated at Sakha, Kafrelhamam and Sids Stations while parents, F 1 and F 2 were evaluated at Sakha. The results showed that genotypes carrying Yr5, Yr8, Yr10, Yr15, Yr27, Yr33, Yr37, Yr51, Yr57 , YrKK and YrALD yellow rust resistance genes recorded resistance to Puccinia striiformis tritici pathotypes at all locations. All the crosses between the monogenic lines carrying Yr8, Yr15 and Yr27 genes recorded resistant field response while, most crosses including Yr34 and Yr57 showed susceptibility. High estimates for genetic variance and broad sense heritability were obtained for all crosses indicating that selection to yellow resistance would be practiced in segregating generations. The highest number of resistant F 2 plants was recorded in crosses of Yr15 to any of the four susceptible wheat cultivars. Based on this study, the efficiency of genes can be arranged in the order of Yr15 ˃ Yr8 ˃ Yr27 ˃ Yr57 with Misr-1 and Misr-2 background and Yr15 ˃ Yr27 ˃ Yr8 ˃ Yr57 ˃ Yr34 with Gemmeiza-11 and Shandaweel-1 background. Therefore, it is recommended to introduce and pyramid Yr8 , Yr15 , Yr27 and Yr57 yellow rust resistance genes in the national wheat breeding program for yellow rust genetic control. The selected F 2 plants from this study can be used to create genetic diversity and obtain high yielding wheat germplasm carrying these effective genes.