中国西北地区禾谷类条锈菌群体的毒性结构分析

Analysis of the virulence constitution of stripe rust pathogen Puccinia striiformis West in northwest China

为明确中国西北地区大麦条锈菌群体的毒性结构及其与小麦条锈菌的交流程度,采用"Flor基因对基因"假说,对采自甘肃省的398份小麦条锈菌标样和采自甘肃、青海及四川省的67份大麦条锈菌标样进行毒性测定、致病类群及专化型分析,同时对侵染大麦的小麦条锈菌标样进行致病范围测定。结果表明,大麦条锈菌与小麦条锈菌对17个小麦条锈病近等基因系材料均致病,其中,小麦条锈菌对近等基因系的13个抗性基因的毒性频率在56.82%及以上,而大麦条锈菌仅对1个抗性基因的毒性频率达到56.82%以上。通过对2个条锈菌专化型群体进行致病类群分析,发现二者都含有贵农22、水源11、杂46及中四致病类群,表明大麦条锈菌与小麦条锈菌的毒性结构有较大差异,但2个专化型之间有毒性交流,贵农22类群在小麦条锈菌和大麦条锈菌专化型群体中均占第一位。利用100份甘肃省小麦条锈菌对大麦进行致病性测定,发现有10.00%的小麦条锈菌能够侵染西北地区的大麦主栽品种。

In order to determine the virulence constitution of stripe rust pathogen Puccinia striiformis f.sp. hordei（PSD） and the communication between Puccinia striiformis West（PST） and PSD, the virulence constitution of PST and PSD from northwestern China was analyzed. A total of 398 isolates of PST were collected from Gansu Province, and 67 isolates of PSD were collected from Gansu, Qinghai and Sichuan provinces. These isolates were investigated with virulence tests, analysis of pathotype and forma specialis and determination of pathogenic range of PST infecting barley cultivars. The results showed that both PSD and PST could infect 17 near-isogenic lines（NIL） of wheat strip rust; the virulence frequency of PST was ≥56.82% for 13 resistant genes, but the virulence frequency of PSD was above 56.82% for only one resistant gene. There were four pathogenic groups including SU11, G22,HY46 and Zhong 4 in both PSD and PST according to the analysis of pathogenic groups. The results indicated that the difference in the virulence constitutions between PSD and PST was significant, and there was communication between them. Group G22 was the biggest virulence group in PST and PSD.This study found that 10.00% of PST infected major barley cultivars according to the pathogenic testing with 100 isolates of PST from Gansu Province for major barley seeding varieties in northwestern China.