Marker assisted gene pyramiding of leaf rust resistance genes Lr24, Lr28 along with stripe rust resistance gene Yr15 in wheat (Triticum aestivum L.)

Abstract

Two highly effective genes for leaf rust resistance viz., Lr24, Lr28 and a stripe rust resistance gene Yr15 were selected for pyramiding in the background of a susceptible but high yielding bread wheat variety HD2877. The screening against most virulent pathotypes of leaf rust 77-5 (121R63-1) and stripe rust, 46S119 and 78S84 indicated that all the three genes confer a high degree of seedling and adult plant resistance. The use of molecular markers, namely, SCS1302607, SCS421570 and Xgwm273 validated the presence of resistance genes, Lr24 and Yr15 in Sunstar*6/C80-1//V763-2312 and Lr28 in HW2033 both being donors. The application of molecular markers facilitated identification of individual plants in three-way cross (HD2877 x Sunstar*6/C80-1//V763-2312) x HW2033, BC1 -F1 and BC2 -F1 generations possessing the targeted genes. Finally eight plants were selected in BC2 -F2 generation carrying the desired resistance genes, Lr24, Lr28 and Yr15 in different combinations in the background of HD2877. The availability of combination of major rust resistance genes in desirable background would facilitate the strategic deployment of wheat varieties to achieve durable resistance.