小麦新种质YW243抗条锈病新基因的AFLP标记

AFLP Markers Linked with a Stripe Rust Resistance Gene of a New Wheat Germplasm YW243

小麦新种质YW243抗条锈病新基因对条锈菌具有较宽抗谱,对26个不同毒性谱的条锈菌 菌系免疫到近免疫,与已知基因系抗病谱不同,可能为新的基因或基因组合。遗传分析表明,YW243 对条锈菌条中31号小种的抗性由显性单基因YrX控制。通过BSA法对1056对MseI/EcoRI AFLP引 物进行筛选,结果表明7对引物可扩增出多态性片段,通过对F2群体单株遗传连锁分析和作图软件 分析,结果表明,2个AFLP标记M54E63-700、M54E64-699与YrX连锁较紧密、遗传距离为9．27 cM,为该基因的精细作图和分子标记辅助育种打下了一定基础。

A new wheat germplasm YW243 has a wild resistance scope against 26 different isolations of Puccinia striiformis west.tritici. The new wheat germplasm YW243 contains a new resistance gene against stripe rust, tentatively designated YrX, which was located on the long arm of chromosome 2B of wheat. In the study, the resistance pattern of a F2 population （202 individuals） derived from the cross of YW243 and Chinese Spring was analyzed through inoculation with No.31 isolate of Puccinia striiformis west.titici. The response patterns showed that the R/S segregation ratio fits 3/1, suggesting that the gene of interest being a single dominant gene. AFLP markers were then used to search for genetically linked markers to the target gene. Using JoinMap V3.0 with Kosambi＇s function and other options left at default values, two AFLP markers M54E63-700 and M54E654-699 were identified to be tightly linked to YrX, with genetic distances of 9.27cM, at same position.