茶树根腐病拮抗放线菌分离、鉴定及生防潜能研究  

Isolation,identification,and biocontrol potential of antagonistic actinomycetes against tea root rot caused by Fusarium cugenangense

作　　者：李桂花 谭琳[3] 沈程文[1,2] 邓玉莲 黄虹 史子涵 吉进军 胡秋龙 LI Guihua;TAN Lin;SHEN Chengwen;DENG Yulian;HUANG Hong;SHI Zihan;JI Jinjun;HU Qiulong(The Key Laboratory of Tea Science of Ministry of Education,Hunan Agricultural University,Changsha 410128,China;College of Horticulture,Hunan Agricultural University,Changsha 410128,China;College of Plant Protection,Hunan Agricultural University,Changsha 410128,China;Hunan Tea Group Company Limited,Changsha 410126,China)

机构地区：[1]湖南农业大学茶学教育部重点实验室,长沙410128 [2]湖南农业大学园艺学院,长沙410128 [3]湖南农业大学植物保护学院,长沙410128 [4]湖南省茶业集团股份有限公司,长沙410126

出　　处：《植物保护》2024年第5期87-96,204,共11页Plant Protection

基　　金：2021年度湖南省重点研发计划(2022NK2051);2021年度湖南省科技创新重大项目(2021NK1020);国家重点研发计划(2022YFD16000803)。

摘　　要：为了开发对茶树根腐病菌具有拮抗作用的放线菌资源,从茶树根际土壤中筛选得到一株对根腐病具有良好防治效果的拮抗菌株JK-13,基于形态特征观察、生理生化试验及16S rRNA序列分析,确定菌株JK-13为胶样链霉菌Streptomyces gelaticus。平板对峙试验结果表明,菌株JK-13对茶树根腐病菌Fusarium cugenangense抑菌率达67.06%,对多种作物的病原真菌表现出了良好的抑菌活性。此外,该菌通过产生具有抑菌活性的挥发性与非挥发性有机物、代谢产物与淀粉水解酶、纤维素水解酶和β-1,3-葡聚糖酶等胞外酶抑制病原菌生长,对峙培养5 d后病原菌菌丝出现分枝、缢缩、扭曲、畸形、相互缠绕等现象。通过优化发酵培养条件来提升活性代谢产物的含量与病原菌抑制率,结果表明,最适生长碳源、氮源、无机盐分别为麦芽糖、(NH_(4))_(2)SO_(4)、KCl,最佳发酵培养基配方为小米10 g/L、麦芽糖10 g/L、(NH_(4))_(2)SO_(4)5 g/L、KCl 2.5 g/L、CaCO_(3)3 g/L,无菌发酵滤液对病原菌抑制率为51.03%,较初始培养条件提高了12.26%。因此,胶样链霉菌JK-13在防控茶树根腐病方面具有较好的开发价值及应用潜力。To discover actinomycete resources with an antagonistic effect on the root rot of Camellia sinensis,a strain JK-13 with strong antagonistic activity against the tea root rot pathogen Fusarium cugenangense was screened from rhizosphere soil of C.sinensis.Strain JK-13 was identified as Streptomyces gelaticus based on morphological,physiological,and biochemical characteristics,and 16S rRNA sequence analysis.The results of the plate confrontation test showed that JK-13 had a high inhibition rate of 67.06%against F.cugenangense,demonstrating good broad-spectrum antagonistic ability toward various pathogenic fungi.In addition,strain JK-13 inhibited the growth of pathogenic fungi by producing volatile and non-volatile organic compounds,metabolites,and extracellular enzymes such as starch hydrolase,cellulose hydrolase,andβ-1,3-glucanase.Light microscopy observation revealed that the pathogenic mycelium appeared branched,constricted,distorted,deformed,and intertwined after confrontation culture for five days.Fermentation conditions were optimized to increase the content of active metabolites and the inhibition rate of strain JK-13 against pathogen F.cugenangense.The results of fermentation condition optimization showed that the most suitable carbon source,nitrogen source,and inorganic salt for growth were maltose,(NH_(4))_(2)SO_(4),and KCl,respectively.The optimal fermentation medium formula was millet 10 g/L,maltose 10 g/L,(NH_(4))_(2)SO_(4)5 g/L,KCl 2.5 g/L,and CaCO_(3)3 g/L.The inhibition rate of the sterile fermentation filtrate of strain JK-13 against F.cugenangense was 51.03%,an increase of 12.26%compared to the initial culture condition.Therefore,S.gelaticus JK-13 has good development value and application potential in the disease management of tea root rot.

关 键 词：茶树根腐病 Fusarium cugenangense 胶样链霉菌 生物防治 

分 类 号：S435.711[农业科学—农业昆虫与害虫防治] S476[农业科学—植物保护]