摘要
本文对柑橘溃疡病菌进行分离鉴定,并研究血散薯Stephania dielsiana Y.C.Wu内生真菌提取物对柑橘溃疡病菌的抑制活性,为柑橘溃疡病微生物源防治剂的开发奠定基础。利用组织分离法和平板划线法从患柑橘溃疡病的沃柑叶中分离纯化得到菌株KY(F),其在NA培养基上菌落呈黄色、圆形、黏稠状、全缘、有光泽、表面微隆起;经染色和形态学观察确定其为革兰氏阴性菌,具有极生单鞭毛,有荚膜;PCR结果显示菌株KY(F)能扩增出符合预期大小的目的条带(413 bp),具有和柑橘溃疡病原菌相同且独有的保守蛋白基因;根据柯赫氏法则,将菌株KY(F)接种到健康沃柑离体叶片上能产生典型的柑橘溃疡病症状,确定菌株KY(F)为柑橘溃疡病菌。通过带毒平板法测定18种血散薯内生真菌乙酸乙酯提取物对该病原菌的抑制活性。结果表明,供试浓度为5 g/L时,18种提取物对KY(F)均能完全抑制,MIC值为0.3125~5 g/L。其中6株内生真菌(Stdif6、叶-7、叶-9、J-10、J-29和Y-10)的提取物对柑橘溃疡病菌的抑制活性最高,MIC值为0.3125~0.625 g/L,均小于1 g/L;其次为5株内生真菌(J-8、J-21、J-36、Y-64、和YB-5)的提取物,MIC值为1.25 g/L,均小于2 g/L;Stdif9和Y-66提取物对柑橘溃疡病菌也有较高的抑制活性,MIC值为2.5 g/L;叶-11、Y-51、Y-59、YB-25和YB-26这5种提取物对柑橘溃疡病菌的抑制活性较其他菌株提取物低,MIC值为5 g/L。研究结果为后期从血散薯内生真菌次生代谢产物中寻找柑橘溃疡病防治剂提供参考。
In this paper,the citrus canker pathogen,was isolated and identified,and the inhibitory activity of endophytic fungi associated with Stephania dielsiana Y.C.Wu against the pathogen was studied,which will lay a foundation for the development of microbial control agents for citrus canker disease.The pathogenic strain KY(F)was isolated from the infected Orah citrus leaves with canker disease using tissue isolation and streak plate methods.The bacterial colonies on NA medium were yellow,round,viscous,full edge,glossy,and slightly raised on the surface.After staining and morphological observation,it was found that it is a gram-negative bacterium with polar single flagella and a capsule.The PCR results showed that strain KY(F)could amplify a target band of expected size(413 bp),with a unique conserved protein gene similar to that of citrus canker pathogen.According to the Koch’s rule,the pathogen was inoculated to healthy detached leaves of Orah citrus,and typical symptoms of citrus canker disease was formed.The results indicated that strain KY(F)was a citrus canker pathogen.The inhibitory activity of ethyl acetate extracts from 18 endophytic fungi isolated from S.dielsiana against this pathogen was determined using the toxin plate method.When the test concentration was 5 g/L,all 18 extracts could completely inhibit strain KY(F),with a MIC value ranging from 0.3125 g/L to 5 g/L.The extracts of six endophytic fungi(Stdif6,leaf-7,leaf-9,J-10,J-29,and Y-10)showed the highest inhibitory activity against strain KY(F),with MICs ranging from 0.3125 g/L to 0.625 g/L,all less than 1 g/L.Next were extracts of 5 endophytic fungi(J-8,J-21,J-36,Y-64,and YB-5),with MICs all at 1.25 g/L,all less than 2 g/L.Extracts of Stdif9 and Y-66 also had high inhibitory activity against citrus canker pathogenic strain KY(F),with MICs both at 2.5 g/L.The inhibitory activity of the five extracts,leaf-11,Y-51,Y-59,YB-25,and YB-26,against strain KY(F)is lower than that of other extracts,with MICs all at 5 g/L.The research results laid a foundation for the application of secondary metabolites of endophytic fungi associated with S.dielsiana in the prevention and control of citrus canker disease.
作者
刘铭希
李奇聪
冉川
张丝
施慧露
邓志勇
骆海玉
邓业成
LIU Mingxi;LI Qicong;RAN Chuan;ZHANG Si;SHI Huilu;DENG Zhiyong;LUO Haiyu;DENG Yecheng(Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection(Guangxi Normal University),Ministry of Education,Guilin Guangxi 541006,China;Guangxi Key Laboratory of Landscape Resources Conservation and Sustainable Utilization in Lijiang River Basin(Guangxi Normal University),Guilin Guangxi 541006,China;College of Life Sciences,Guangxi Normal University,Guilin Guangxi 541006,China;Institute for Sustainable Development and Innovation,Guangxi Normal University,Guilin Guangxi 541006,China)
出处
《广西师范大学学报(自然科学版)》
北大核心
2025年第1期39-47,共9页
Journal of Guangxi Normal University:Natural Science Edition
基金
广西自然科学基金(2021GXNSFAA196064)
广西重点研发计划(桂科AB21196065,桂科AB22080071)。
关键词
柑橘溃疡病菌
血散薯
内生真菌
抑菌活性
活性物质
生物防治剂
Xanthomonas citri subsp.citri
Stephania dielsiana Y.C.Wu
endophytic fungi
inhibitory activity
active substances
biological control agents
