小麦品系P81抗条锈性遗传分析

Genetic analysis of stripe rust resistance in wheat line P81

小麦条锈病是小麦生产中最重要的病害,培育抗病品种是防治条锈病的有效措施。小麦品系P81在苗期和成株期对当前流行的条锈菌小种条中30、31和32均表现免疫。以感病品种川麦28、Taichung29作母本,P81作父本通过杂交分别配制了F1、F2和BC1、BC2代,用人工接种方法研究P81及其杂交后代对条中32号的苗期抗性并进行了遗传分析;同时,将P81分别与含有抗条锈基因的Yr5、Yr10、Yr15、Yr26材料进行杂交配制F2,用条中32号小种对其F2进行抗感鉴定,确定抗性基因的等位性。结果表明,P81与川麦28、Taichung29杂交F1代植株对条锈菌条中32号小种表现出与P81相似的高抗,说明P81中的抗条锈基因为显性表达。根据P81与川麦28、Taichung29杂交的F2、BC1、BC2代植株的抗性分离情况及F1代植株及亲本的抗性表现,说明P81对条中32号的抗性由1对显性抗条锈病基因控制;用条中32号小种接种鉴定P81与已知抗锈基因Yr5、Yr10、Yr15、Yr26构建的F2群体时均出现了感病植株,说明P81中的抗条锈病基因与Yr5、Yr10、Yr15、Yr26不相同;系谱分析表明,该基因来源于叙利亚普通小麦品系叙29。

Stripe rust caused by Puccinia striiformis f. sp. tritici is one of the most important wheat diseases in many regions of world including China. So far, breeding for resistance eultivars has been proved the most economic and effective approach for the control of this disease. A wheat line P81 showed excellent resistance to stripe rust isolates CYR30, CYR31 and CYR32 at seedling and adult stage. In this paper, F1, F2 and BC1, BC2 seeds were respectively prepared by crossing Chuanmai28 and Taiehung29, two highly susceptible varieties, as female parent and P81 as male parent. Resistance of P81 and its two hybrid progenies were analyzed genetically by artificial inoculation with CYR32 at seedling stage. High resistance of two F1 plants to the race CYR32, similar to that of P81, indicated that the resistance gene in P81 was dominant. Based on the data of resistance phenotypes of F1 , F2, BC1 of Chuanmai28/P81 and their parents by inoculated CYR32, it was showed there was a dominant gene in P81. While, the same result was gotten from the populations F2, BC2 in Taichung29/P81 inoculated CYR32. By allelie test, it indicated that the resistance gene in P81 was different from Yr5, Yr10, Yr15 and Yr26. Through pedigree analysis, it showed that the resistance gene in P81 derived from Syria common wheat line Xu29. The seresults suggested that the line P81 as a resistance resource had a considerable value in wheat breeding for stripe rust.