An AFLP marker linked to the leaf rust resistanc gene LrBi16 and test of allelism with Lr14a on chromosome arm 7BL

摘要

Leaf rust(LR), caused by Puccinia triticina, is one of the most widespread diseases of common wheat(Triticum aestivum L.) worldwide. The LR resistance gene Lr Bi16 has been mapped on chromosome arm 7BL in Chinese wheat cultivar Bimai 16 and was closely linked to SSR loci Xcfa2257 and Xgwm344 with genetic distances of 2.8 c M and 2.9 c M, respectively. In the present study, a total of 304 AFLP primer pairs were used to screen Bimai 16 and Thatcher and resistant and susceptible DNA bulks. The polymorphic AFLP marker P-ATT/M-CGC173 bp was used to genotype F2 and F3populations to identify markers more closely linked to Lr Bi16. Marker P-ATT/M-CGC173 bp was tightly linked to Lr Bi16 with a genetic distance of0.5 c M. As Lr Bi16 was mapped near the Lr14 a locus, 809 F2 plants from the Bimai 16/RL6013(Lr14a) cross were inoculated with the Pt pathotype FHNQ to test the allelism of Lr14 a and Lr Bi16. All of the F2 plants were resistant to FHNQ(IT between; and 2), suggesting that Lr14 a and Lr Bi16 are allelic.