甘肃河西冷凉地区葡萄灰霉病病原鉴定及生物药剂筛选

Pathogen Identification and Biological Agent Screening of Grape Grey Mold in Hexi cold area of Gansu

本研究采用常规组织分离法对甘肃省河西冷凉地区葡萄灰霉病罹病叶片及果实病原进行了分离纯化、病原形态特征观察、致病性测定和分子生物学鉴定。结果表明:代表菌株G-001和G-002均具有灰葡萄孢菌Botrytis cinerea的形态特征;采用r DNA-ITS和G3PDH基因法对菌株G-001和G-002的基因组DNA进行PCR扩增测序,并进行同源性在线比对。比对结果G-001和G-002与树莓、鹰嘴豆上分离的灰葡萄孢菌B.cinerea的同源性达到100%,与木瓜Chaenomeles sinensis、酸模Rumexacetosa、苦荞麦Fagopyrum tataricum上分离的灰葡萄孢菌Botrytis cinerea的同源性达到99.89%。分子生物学结合病原形态学将G-001和G-002菌株均鉴定为灰葡萄孢菌B.cinerea。采用柯赫氏法则对G-001和G-002菌株进行致病性研究,结果表明G-001和G-002对葡萄果实均具有致病性。室内毒力测定结果表明:3种生物农药对葡萄灰霉病菌都有抑制作用,其中哈茨木霉的毒力最强,其EC50值为47.36 mg/L,寡雄腐霉素毒力较弱,其EC50值为928.28 mg/L。

In this study,the pathogens from leaves and fruits infected with gray mould of grapevine were isolated and purified,morphological characteristics of the pathogens were observed,pathogenicity was determined and molecular biological identification was carried out by conventional tissue separation method.The results showed that the representative strains G-001 and G-002 had the morphological characteristics of Botrytis cinerea.The genomic DNA of strains G-001 and G-002 was amplified and sequenced by PCR using rDNA-ITS and G3PDH gene methods,and the homology was compared online.The homology of G-001 and G-002 with B.cinerea isolated from raspberry and chickpea reached 100%.The homology with B.cinerea isolated from Chaenomeles sinensis,Rumexacetosa and Fagopyrum tataricum reached 99.89%.Both G-001 and G-002 strains were identified as B.cinerea by molecular biology and morphological analysis.Koch postulates rule was used to study the pathogenicity of G-001 and G-002 strains,and the results showed that G-001 and G-002 were both pathogenic to grape fruits.The results of laboratory toxicity test showed that the three biopesticides had inhibitory effects on B.cinerea,among which Trichoderma harzianum had the strongest toxicity,with EC50 value of 47.36 mg/L,and Pythium oligandrum had the weaker toxicity,with EC50 value of 928.28 mg/L.