关键词: 分子遗传学, 小麦, 十倍体长穗偃麦草, 抗条锈病基因, 分子标记, 染色体定位

Abstract: 【Objective】Loss of varietal resistance to stripe rust (Puccinia striiformis Westend f. sp. tritici) is an important factor causing massive periodical epidemic of rust in China′s wheat producing areas. Creation and development of new races of rust pathogen have led widely cultivated varieties into serious crisis of resistance loss. So searching new resistance genes is a long-term strategic task. 【Method】 and 【Result】A-3 line with high resistance (immunity) to current epidemic yellow rust races (CY29, 31, 32) was screened out in offspring of Triticum aestivum × Thinopyrum ponticum. Segregation in F2 and BC1 populations indicated that the resistance was controlled by two independent genes, a dominant gene and one recessive gene, respectively. SSR markers were employed to map the two resistance genes in the F2 and BC1 population. A marker WMC477-167bp locating on 2BS was linked to the dominant gene with genetic distance of 0.4 cM. Another marker WMC364-208bp locating on 7BS was linked to the recessive resistance gene with genetic distance of 5.8 cM. The two genes identified in this paper might be two novel stripe rust resistance genes, which were temporarily designated as YrTp1 and YrTp2, respectively. 【Conclusion】Good resistance to CY31 and CY32, availability of the tightly linking SSR markers can assist rapid transfer of the resistance genes into new varieties to control the epidemic of the two races in wheat production.

Key words: Molecular genetics, Wheat (Triticum aestivum), Thinopyrum ponticum, Stripe rust resistant gene, SSR, Mapping