浙江省鲜食大豆炭疽病病原分离及抗性鉴定

Identification of the pathogen of vegetable soybean anthracnose in Zhejiang Province and evaluation of soybean cultivars for resistance to Colletotrichum truncatum

炭疽病是我国南方鲜食大豆最重要的病害之一。本试验通过组织分离法,在浙江省鲜食大豆主栽区炭疽病病荚中分离得到9株疑似炭疽病菌分离物。根据分离物的形态特征、基于ITS-GAPDH-CHS-1-TUB2基因序列的系统发育分析、分离物的致病性将这些分离物鉴定为平头炭疽菌(Colletotrichum truncatum)。对51份栽培大豆品种鼓粒初期豆荚离体喷雾接种强致病力分离物CT5,这些品种表现出明显抗/感差异,其病斑大小被用于大豆平头炭疽菌抗病性分级标准。在供试的这些品种中,发现了3份高抗品种,9份抗病品种,20份中抗品种。本研究明确了浙江省鲜食大豆炭疽病病原,提供了部分大豆品种资源抗病性信息,为深入研究该病发生规律、防治、抗病机制及培育抗病新品种等奠定基础。

Anthracnose is one of the most important diseases of vegetable soybean in South China,especially in Zhejiang Province.In this study,by tissue separation method,nine Colletotrichum-like isolates were isolated from diseased vegetable soybean pods in different planting areas in Zhejiang Province.In order to identify these isolates,typical morphological characteristics were analyzed,phylogenetic tree was constructed based on ITS-GAPDH-CHS-1-TUB2 genes,and their pathogenicity were tested.Finally,these isolates were identified as Colletotrichum truncatum.Fresh pods from 51 soybean cultivars that showed significant differences in the disease resistance/susceptibility in the field,were inoculated in vitro by spraying strong-virulence isolate CT5,and significant differences of resistance/susceptibility of 51 cultivars were observed,which was mainly consistent with their performances of resistance/susceptibility in the field.Finally,three highly resistant cultivars,nine resistant ones,20 moderately resistant ones were identified.This study clarified the pathogens of vegetable soybean anthracnose in Zhejiang Province,and identified 32 cultivars with higher anthracnose disease resistance.The results would enlighten further researches in occurrence,prevention strategy,resistance mechanism of the soybean anthracnose disease and provide new resistant soybean cultivars in future vegetable soybean breeding program.