小麦‘西农291’成株期抗条锈病遗传分析

为明确‘西农291’抗条锈性的遗传基础。对‘西农291’在温室和田间进行多个小麦条锈菌小种的抗条锈鉴定；采用常规杂交方法，将‘西农291’分别与感病品种‘铭贤169’与AvS杂交，构建其F1、F2遗传群体，用小麦条锈菌小种CYR32进行温室抗条锈性鉴定、混合小种（CYR32:CYR33≈1:1）进行田间抗条锈性鉴定。结果表明，在温室条件下，‘西农291’在苗期对条锈菌CYR32与CYR33表现高度感病、成株期对CYR32、CYR33、Su11-4及Su11-7表现高度抗条锈性；田间混合小种接种诱发发病（陕西杨凌）和自然发病（甘肃天水）抗条锈性鉴定均表明‘西农291’在成株期高度抗条锈病。群体抗条锈性鉴定结果表明‘西农291’与感病品种铭贤169和AvS杂交的F2群体的抗:感分离比例均符合3R:1S的理论比例。以上结果说明‘西农291’具有非小种专化性的、广谱抗性的成株期抗条锈性；对CYR32的成株抗条锈性受1对显性基因控制。

Genetic Analysis on Adult Plant Resistance to Puccinia striiformis f. sp. tritici in Wheat ‘Xinong 291’

The aim was to determine the inheritance of resistance in‘Xinong 291’.In this study,the level of resistance to wheat stripe rust in‘Xinong 291’was identified using the predominant races of Chinese Yellow Race（CYR） in the greenhouse and the field.Simultaneously,two susceptible cultivars,‘Mingxian 169’and Avocet Susceptible（AvS） ,were used to cross with the resistant cultivar‘Xinong 291’for constructing F_1 and F_2 genetic populations.Genetic analysis was performed with CYR32 at the adult stage in the greenhouse,and mixed races consisting of CYR32 and CYR33 at a ratio of 1：1 at the adult stage in the field,respectively.The results showed that,in the greenhouse,‘Xinong 291’was susceptible to the CYR races of CYR32 and CYR33 at the seedling stage,and highly resistant to the CYR races of CYR32,CYR33,Su11-4,and Su11-7 at the adult stage,respectively.In the field,high resistance to wheat stripe rust in‘Xinong 291’was demonstrated by inoculating the mixed races consisting of the predominant CYR races in Yangling,Shaanxi Province,and by natural infection in Tianshui,Gansu Province,respectively.The chi-squre test confirmed that the frequencies of resistance versus susceptible individuals were in accordance with the 3R：1S ratio in the F 2 populations of‘Xinong 291’בMingxian 169’and‘Xinong 291’×AvS.These results indicated that‘Xinong 291’was of non-race specific and broad spectrum of the adult-plant resistance,and that the resistance o‘fXinong 291’to wheat stripe rust was controlled by a single dominant gene.