我国大蒜主产区大蒜根腐病病原真菌的分离及致病性初步研究

Preliminary study on isolation and pathogenicity of pathogenic fungi of garlic Root Rot in the main production area of garlic in China

大蒜根腐病是我国大蒜主产区山东省金乡县及其周边地区大蒜的主要病害之一。采用常规组织分离法,从连续3年采集的51份大蒜根腐病根样品中分离纯化潜在大蒜根腐病病原菌真菌62株,通过形态学和分子生物学对菌株进行鉴定,结果显示主要类群为镰刀菌属(Fusarium)和茎点霉(Setophoma);采用柯赫氏法则,明确镰刀菌属H9为大蒜根腐病病原菌;采用温室水培试验,研究不同浓度大蒜根腐病病原菌H9对大蒜幼苗的致病能力,结果显示致病能力与接种量呈正相关,接种孢子浓度2×10^(9) cfu/mL、接菌量为100和150 mL,40 d后就可以导致大蒜幼苗产生严重的根腐病。综上,我国山东及周边地区大蒜主产区根腐病的主要病原真菌为镰刀菌属(Fusarium)和茎点霉属(Setophoma),为该地区大蒜根腐病的科学防治提供理论依据。

Garlic Root Rot is one of the main diseases of garlic in Jinxiang county and its surrounding areas of Shandong province.In this study,62 strains of potential pathogenic fungi of garlic Root Rot were isolated and purified from 51 samples of garlic Root Rot collected for 3 consecutive years by conventional tissue isolation method.Morphological and molecular biological identification showed that the main groups of these fungi were Fusarium and Setophoma.According to Koch’s rule,the Fusarium H9 was confirmed to be the pathogen of garlic root rot.The pathogenicity of garlic root rot pathogen H9 with different concentrations on garlic seedlings was studied by hydroponics experiment in greenhouse.The results showed that the pathogenicity was positively corelated with the inoculation amount.Serious Root Rot appeared in garlic seedlings after 40 days inoculation with spore concentration of 2×10^(9) cfu/mL,inoculation amount of 100 and 150 mL,respectively.In summary,the main pathogenic fungi of Root Rot of garlic in Shandong and its surrounding areas are Fusarium and Setophoma,which provide a theoretical basis for the scientific control of garlic Root Rot in this area.