Transfer of the high-temperature adult-plant stripe rust resistance gene Yr62 in four Chinese wheat cultivars

Wheat stripe rust is one of the diseases that seriously affect wheat production worldwide. Breeding resistant cultivars is an effective way to control this disease. The wheat stripe rust resistance gene Yr62 has high-temperature adult-plant resistance (HTAP). In this study, PI 660,060, a single Yr62 gene line, was crossed with four Chinese wheat cultivars, LunXuan987 (LX987), Bainongaikang58 (AK58), ZhengMai9023 (ZM9023), and HanMai6172 (H6172). F-1 seeds of four cross combinations were planted and self-crossed to develop the advance generations in the field. The seeds of each cross were mixed harvested and about 2400 to 3000 seeds were sown in each generation for F-1 to F-4 to maintain the maximum possible genotypes. Forty-five lines were selected and evaluated for resistance to stripe rust and agronomic traits, including plant height, number of grains per spike, and tiller number, in F-5 and F-6. Then, 33 lines with good agronomic traits and high disease resistance were developed to F-9 generation. SSR markers Xgwm251 and Xgwm192 flank linked with the Yr62 were used to detect the presence of Yr62 in these 33 F-9 lines. Of these, 22 lines were confirmed with the resistance gene Yr62. Finally, nine lines with good agronomic traits and disease resistance were successfully selected. The selected wheat lines in this study provide material support for the future breeding of wheat for stripe rust resistance.