源自陕、甘野生小檗的小麦条锈菌有性生殖后代的毒性分析  

Virulence analysis of sexual progeny of the wheat stripe rust pathogen recovered from wild barberry in Shaanxi and Gansu

作　　者：李巧[1] 覃剑锋[1] 赵元元[1] 赵杰[1] 黄丽丽[1] 康振生[1] 

机构地区：[1]西北农林科技大学植物保护学院旱区作物逆境生物学国家重点实验室,杨凌712100

出　　处：《植物病理学报》2016年第6期809-820,共12页Acta Phytopathologica Sinica

基　　金：国家自然科学基金(32171986);国家"973"项目(2013CB127700);国家"863"计划(2012AA101503);国家小麦产业技术体系(CARS-3-1-11);国家国际科技合作专项资助(2011DFG32990);新世纪优秀人才支持计划

摘　　要：小麦条锈病是我国最具毁灭性的小麦病害之一,其流行常常造成小麦严重减产。种植抗病品种是防治该病害最经济、有效和环保的措施。但是,由于新毒性菌系的出现,抗病品种在种植短短数年内便"丧失"其抗病性。研究证实病原菌毒性变异产生新菌系是导致小麦品种抗病性"丧失"的根本原因。近年来,随着小麦条锈菌转主寄主小檗的确定,发现自然条件下我国小麦条锈菌在野生小檗上可以完成有性生殖。本研究通过对2015年自然发病小檗小麦条锈菌的分离及其单夏孢子堆纯化,利用中国鉴别寄主进行了毒性测定分析。从陕西、甘肃两省的3种感病小檗共分离获得小麦条锈菌菌系8个,其中有1个菌系与已知小种Su11-126的毒性完全匹配,其余7个为新菌系;93个单夏孢子堆群体可分为47个不同的致病类型,包括14个已知小种类型,33个新小种类型;有56个菌系与已知小种的毒性完全匹配,37个为新小种。本研究再次获得了条锈菌自然条件下存在有性生殖并因此导致新菌系产生的证据,证实了野生小檗在我国小麦条锈菌的生活史和病害循环中具有作用。Wheat stripe rust is one of the most destructive wheat diseases in China and frequently resulted in se- rious yield loss in wheat production. Growing resistant wheat cultivars is considered as the most economic, effec- tive, and environmental-friendly approach for controlling the disease. However, the resistance of wheat cultivars was overcome by emergence of new races of Puccinia striiformis f. sp. tritici （ Pst）, the causal fungus of wheat stripe rust, within a few years after release of the resistant cultivars. Previous studies demonstrated that the loss of resistance of wheat cultivars resulted from emergence of new rust races due to virulence variation of the patho- gen. In recent years, as the discovery of barberry （Berberis spp.） serving as alternate host for Pst, we firstly reported that Pst completes its sexual reproduction on wild barberry under natural conditions in China. Our objec- tives in this study were therefore to isolate Pst samples from naturally infected Berberis, establish their single- uredium populations, test their virulence based on the differential set, and analyze virulence characteristics of their single-uredium populations. We isolated 8 Pst samples from 3 Berberis spp. collected from Gansu and Shaanxi provinces in 2015. Basedon their virulence tests and analyses, only one Pst sample was matched to the known Pst race Sull-126 in ＇virulence patterns, and the remaining 7 were new races. Out of 93 isolated single-uredium populations that produced 47 virulence patterns including 14 known race types and 33 new race types, fifty-six were matched with the known Pst races in virulence patterns and 37 were new. In this study, we obtained more evidences for supporting the existence of sexual reproduction of Pst on Berberis spp. under natural conditions in China, which led to the generation of new races of the pathogen. Our results confirmed that wild Ber- beris spp. play a role in completion of the whole life cycle of Pst and in disease cycle of wheat stripe rust in China.

关 键 词：小麦 条锈病 有性生殖 毒性变异 小檗 

分 类 号：S435.121.42[农业科学—农业昆虫与害虫防治]