[Genetic analysis and molecular markers of a novel stripe rust resistance gene YrHua in wheat originated from Psathyrostachys huashanica Keng]

Abstract

The H9020-17-5,a common wheat-Psathyrostachys huashanica Keng translocation line, possesses excellent resistance to wheat stripe rust. Genetic analysis of F2 and BC1 populations derived from H9020-17-5 x Mingxian169 indicated that resistance to stripe rust in H9020-17-5 was a dominant character controlling by single gene originated from Ps. huashanica. This resistance gene originated from Ps. huashanica was first reported in the present study and named as YrHua. In order to map the resistance gene YrHua, AFLP approach was employed to analyze the 119 individuals of H9020-17-5 x Mingxian169 F2 population which were inoculated by stripe rust isolate CY30. As a result,two markers, PM14(301) and PM42(249) were found to be linked to the resistance gene YrHua,and the genetic distances between the markers and target gene were 5.4 cM and 2.7 cM, respectively. For the convenience of marker-assisted selection in wheat breeding, one of the two AFLP markers was converted to PCR marker using a pair of special primers based on the DNA sequence of PM14 (301) and the polymorphism of restriction site. Our research results provided a useful tool for marker-assisted selection and laid a foundation of fine mapping and map based cloning of YrHua gene.