摘要
为了利用生防菌有效防控花生白绢病Sclerotium rolfsii,本研究采用稀释培养法从花生根际土中分离木霉菌,采用平板对峙法和盆栽试验筛选对花生白绢病具有高效生防效果的菌株并测定其生防机制,通过形态学、分子生物学技术和环境因子对发育的影响确定生防菌株的分类地位及生物学特性。结果表明,从分离的132株木霉菌中筛选出1株对齐整小核菌S.rolfsii具有高效抑菌效果的菌株GH-20,抑菌率达89.93%,将其鉴定为棘孢木霉菌Trichoderma asperellum。对峙培养时,菌株GH-20对齐整小核菌的拮抗指数达Ⅰ级,当其菌落覆盖病原菌菌落后,其菌丝缠绕和侵入病原菌菌丝,并使病原菌菌丝体逐渐消解、减少,导致病原菌不能产生菌核;菌株GH-20产生的挥发性代谢产物(volatile gas,VOG)和非挥发性代谢产物(non-VOG)对病原菌的抑菌率分别为59.95%和79.49%。盆栽试验结果表明,同时接种菌株GH-20和齐整小核菌对花生白绢病生防效果最好,为79.64%。另外,该菌株具有在以果糖为碳源,以酵母膏为氮源和pH 7的条件下生长发育较好,光照有利于生长而光暗交替有利于孢子形成等生物学特性。生防机制研究结果显示,棘孢木霉菌GH-20主要通过竞争、重寄生作用和产生拮抗物质抑制和消解齐整小核菌,从而起到防病效果。
In order to screen beneficial microorganisms for effectively controlling peanut southern blight caused by Sclerotium rolfsii,Trichoderma spp.was isolated from peanut rhizosphere soil by soil dilution method,the strain with the highest biocontrol effect on S.rolfsii was screened by dual culture method and pot experiment and identified by morphological and molecular biological techniques.Its biocontrol mechanism against peanut southern blight and biological characteristics were determined.The results indicated that strain GH-20 was screened from 132 isolates of Trichoderma and had significant inhibition activity to S.rolfsii,with the rate of 89.93%.The strain was identified as Trichoderma asperellum.During dual culture,antagonism index of GH-20 to the S.rolfsii was grade I.After the strain GH-20 completely cover the colony of the pathogen,GH-20 mycelium can wrap and invade the pathogen hyphae,resulting in mycoparasitism,and gradually digest and reduce its mycelium,resulting in inability of the pathogen to produce sclerotia.The inhibition rates of volatile gas(VOG)and non-volatile gas(non-VOG)produced by GH-20 against the pathogen were 59.95%and 79.49%,respectively.Pot experiment showed that the biocontrol efficacy of GH-20 on peanut southern blight was 79.64%.Under conditions of fructose as carbon source,yeast extract as nitrogen source and the optimal pH value of 7,GH-20 was more conducive to growth and development.Continuous light was conducive to GH-20 mycelial growth,while alternating light and dark conditions were conducive to spore production.In conclusion,T.asperellum GH-20 could effectively control the peanut southern blight mainly through competition,hyperparasitism and antagonistic substances.
作者
李佳昕
蔡晨亮
王琰
张茹琴
王志奎
鄢洪海
LI Jiaxin;CAI Chenliang;WANG Yan;ZHANG Ruqin;WANG Zhikui;YAN Honghai(College of Plant Health and Medicine,Qingdao Agricultural University,Qingdao 266109,China;Shandong Rushan City Agriculture Bureau,Weihai 264500,China;Jimo Agriculture Bureau,Qingdao 266201,China)
出处
《中国生物防治学报》
CSCD
北大核心
2022年第6期1547-1557,共11页
Chinese Journal of Biological Control
基金
国家重点研发计划(2018YFD0201007)。
关键词
花生白绢病
棘孢木霉菌
生物防治
机制
生物学特性
peanut southern blight
Trichoderma asperellum
biocontrol
mechanism
biological characteristics
