源于华山新麦草抗条锈病基因YrH122遗传分析和SSR标记

Inheritance and SSR mapping of a stripe-rust resistance gene YrH122 derived from Psathyrostachys huashanica Keng

H122是1个通过杂交和回交选育的普通小麦-华山新麦草易位系。为明确其抗条锈病基因及遗传特点,建立抗病基因SSR标记,利用我国小麦条锈菌流行小种CYR29、CYR31、CYR32、CYR33和致病类型Su11-4、Su11-11对H122进行苗期抗性鉴定,根据鉴定结果选用CYR32、CYR33和Su11-4对其与铭贤169杂交F1、F2及BC1代进行了遗传分析,同时应用258对SSR引物对将H122/铭贤169 F2代接种Su11-4的185个单株构建的作图群体进行了PCR扩增和电泳分析。结果表明,H122对供试小种均表现免疫或近免疫,对CYR32的抗病性由1对显性基因控制,对CYR33的抗病性由1对隐性基因控制,对Su11-4的抗病性亦由1对显性基因控制,将其暂命名为YrH122。筛选到3个与YrH122连锁的SSR标记Xbarc229、Xwmc339和Xwmc93,遗传距离分别为7.7、4.3和11.0 cM,并将该基因定位于小麦染色体1DL上。SSR标记回检显示,YrH122来源于华山新麦草。通过基因来源、分子检测及染色体位点比较,YrH122可能是1个不同于目前已知抗条锈病基因的新基因。

H122 is one of translocation lines of Triticum aestivum and Psathyrostachys huashanica through cross and back-cross. To identify and map the gene（s） conferring resistance to stripe rust, H122 was inoculated with four Chinese prevalent races, CYR29, CYR3], CYR32 and CYR33, and two pathotypes, Sul]-4 and Su11-ll. Based on resistance identification results, CYR32, CYR33 and Sul]-4 were selected to test the F1, F2 and BC~ generations from the cross H122/Mingxian 169. The results showed that H122 was resistant to all the tested races, and one dominant gene conferring resistance to CYR32, one recessive gene conferring re- sistance to CYR33 and one dominant gene conferring resistance to Sull-4 which was temporarily designated YrH122. Also, linkage group was constructed for YrH122 using 185 F2 populations. Among 258 SSR primer pairs, three SSR primers, Xbarc229, Xwmc339 and Xwmc93, were linked to YrH122 with genetic distance from 4.3 to 11.0 cM. According to the locations of linked markers, the resistance gene was located on chro- mosome 1DL. The results of back tests of the three SSR markers indicated that YrH122 was derived from P. huashanica. Further, based on the source of the gene YrH122, molecular detection and chromosome location, YrH122 might be a novel stripe rust resistance gene.