茶树病害拮抗微生物的筛选与鉴定

茶树病害拮抗微生物的筛选与鉴定尹艺摘要：茶树叶片是茶树经济效益的主要来源，由拟盘多毛孢菌Pseudopestalotiopsiscamelliae-sinensis引起的茶轮班病、炭疽菌Colletotrichum camelliae引起的茶云纹叶枯病以及由茎点霉属真菌Didymella segeticola引起的茶叶斑病是茶树叶部常见的几种真菌性病害，严重影响茶叶产量和品质。生物防治是指利用一些特定的生物或生物的代谢物有效防治病虫害的方法，可分为微生物防治、昆虫天敌防治、植物源农药防治等方面，具有不产生污染、副作用少等优势。本实验分离鉴定了两株可用于拮抗微生物筛选的菌株：菌株C194、菌株C21-7。通过观察菌株C19-4和C21-7的形态学特征并结合分子系统发育树的分析，将菌株C194鉴定为Fusarium avenaceum,将菌株C2l-7鉴定为Trichodema harzianum,以拟盘多毛孢菌、炭疽菌和茎点霉属真菌为研究对象，C194、C21-7为拮抗菌，通过平板对峙法和抑菌圈法进行拮抗筛选，平板对峙实验中，菌株C194对拟盘多毛孢菌的拮抗效果最好，抑菌率分别为76.67%：菌株C21-7对三种病原菌均表现出明显的拮抗作用，其中对炭痘菌的拮抗效果最好，抑制率为80.65%,抑菌圈实验中，菌株C194发酵液对茎点霉属真菌的拮抗效果最好，抑制率为30.87%：菌株C21-7发酵液只对拟盘多毛孢菌有拮抗效果最好，抑制率27.83%，实验明确了菌株C21-7(Trichodema harzianum)与菌株Cl94(Fusarium avenaceum)对炭疽菌、拟盘多毛孢菌及茎点霉属真菌三种病原菌的抑制效果，为菌株C21-7(Trichodema harzianum)和菌株C194(Fusarium avenaceum)拮抗由炭疽菌引起的茶云纹叶枯病、拟盘多毛孢菌引起的茶轮斑病、茎点霉属真菌引起的茶叶斑病的机理探讨和对相关次生防菌菌剂的合理开发利用，奠定了条件基础和理论支撑。关键词：茶树病害：拮抗：抑菌率：鉴定Screening and Identification of Antagonistic Microorganisms in TeaTree DiseasesYin YiAbstract:Tea leaves are the main source of economic benefits of tea trees.Tea wheel spot diseasecaused by Pseudopestalotiopsis camelliae-sinensis,tea blob leaf blight caused by anthraxColletotrichum camelliae and tea leaf spot disease caused by the fungus Didymella segeticola areseveral common fungal diseases in the tea leaves,which seriously affect the yield and quality oftea.Biological control refers to the use of some specific biological or biological metabolites toeffectively control diseases and insect pests,can be divided into microbial control,insect naturalenemy control,plant source pesticide control and other aspects,has the advantages of no pollution,less side effects.Two strains can be used for antagonistic microbial screening:strains C19-4 andstrains C21-7.By observing the morphological characteristics of strains C19-4 and C 121-7combined with analysis of molecular phylogenetic tree,strain C19-4 was identified as Fusariumavenaceum and strain C21-7 as Trichodema harzianum.Polytrictricoides,Colletotrix,andTrichofungi,and C19-4 and C21-7 as antagonistic bacteria,were screened by plate confrontationand bacteriosphere.In the plate confrontation experiment,strain C19-4 had the best antagonisticeffect on P.sinensis,and the inhibition rate was 76.67%;strain C21-7 showed obviousantagonistic effect on the three pathogens,among which the best antagonistic effect and theinhibition rate was 80.65%.In the inhibition experiment,strain C19-4 had the best antagonismeffect against P.sinensis at 30.87%;strain C21-7 had the best antagonism effect against P.sinensis,with the inhibition rate of 27.83%.The experiment confirmed the inhibitory effect of strainsC21-7 (Trichodema harzianum)and C19-4(Fusarium avenaceum)on anththracx,Polytrichosisand fungi,To explore the mechanism of strain C21-7 (Trichodema harzianum)and strain C19-4(Fusarium avenaceum)against the mechanism of tea iumum blight caused by anthracnose,tea leafspot caused by polytricoides,and tea leaf spot caused by fungi,and the rational development andutil