新疆伊犁州小麦条锈菌生理小种鉴定及毒性分析

Physiological race identification and virulence analysis of Puccinia striiformis f.sp.tritici in Yili prefecture,Xinjiang

伊犁州是新疆小麦条锈病重灾区,对该地区开展小麦条锈菌生理小种监测意义重大。本研究通过对2020年采自新疆伊犁4县的149份小麦条锈菌样品进行生理小种监测,以期明确该地区小麦条锈菌生理小种组成及毒性情况。结果表明,共监测到28个生理小种,其中CYR 33、Su 11-1、Su 11-12、CYR 32及CYR 34出现频率较高,分别为14.09%,12.75%,8.05%,8.05%和7.38%;水源11类群为优势类群,出现频率高达44.30%。对抗条锈病基因Yr1、YrA、Yr3、Yr6、YrSu、Yr9的毒性频率均大于70%,表明这些基因在伊犁州抗性基本丧失。新疆伊犁州4县小麦条锈菌毒性多样性分析显示,Nei’s遗传多样性指数为0.34,Shannon信息指数为0.50,表明伊犁州条锈菌毒性多样性水平较高,毒性组成丰富;小麦条锈菌毒性相似系数在0.92~1.00,其中伊宁县和巩留县的样品遗传距离最近,察布查尔县与其他3县样品遗传距离最远。因此,新疆伊犁州地区抗锈育种应以抗CYR 33和Su 11-1为主,兼顾抗Su 11-12、CYR 32和贵农22类群中其他类型。另外不同县区应合理进行抗病基因布局,以期实现小麦条锈病的区域间联合防治。

Wheat stripe rust,caused by Puccinia striiformis f.sp.tritici(Pst),occurred severely in Yili prefecture,Xinjiang in 2020.Monitoring the dynamics of physiological race of Pst was of great significance for disease control.In this study,149 samples were collected from four counties of Yili in 2020 to identify the type of physiological race and the virulence.The results showed that 28 physiological races were acquired,among which CYR 33,Su 11-1,Su 11-12,CYR 32 and CYR 34 were the dominant races with frequencies of 14.09%,12.75%,8.05%,8.05% and 7.38%,respectively.Suwon 11 group was the dominant group which had the highest frequency of 44.30%.Over 70% isolates were virulent to Yr1,YrA,Yr3,Yr6,YrSu and Yr9,suggesting that the resistance genes have almost lost in wheat varieties in Yili prefecture.Virulence diversity analysis in the four countries of Yili prefecture showed that the Nei’s genetic diversity index was 0.34,the Shannon information index was 0.50,which presented high polymorphism.Clustering analysis indicated that the similarity coefficient of virulence was 0.92-1.00.The isolates in Yining county and Gongliu county had the closest genetic distance,and Qapqal county had large genetic gap to the other counties.Therefore,the future breeding in Yili should mainly consider the resistant genes to CYR 33 and Su 11-1,then Su 11-12,CYR 32 and other pathotypes in Guinong 22.Besides,the rational distribution of wheat varieties should be taken among different counties of Yili in order to achieve the goal of comprehensive control of wheat stripe rust.