烟草赤星病拮抗菌的筛选及其生防机理初探  

Screening of antagonistic bacteria against Alternaria alternate,tobacco scab,and preliminary exploration of their biocontrol mechanism

作　　者：孙伟霖 颜霞[1] 高剑欣 崔传斌 王平平 王娜娜[1] 杨明明 黄丽丽[3] Sun Weilin;Yan Xia;Gao Jianxin;Cui Chuanbin;Wang Pingping;Wang Nana;Yang Ming-ming;Huang Lili(College of Life Sciences,Northwest A&F University,Yangling 712100,China;Shannxi Tobacco Company,Xi’an 710000 China;College of Plant Protection,Northwest A&F University,Yangling 712100,China)

机构地区：[1]西北农林科技大学生命科学学院,陕西杨陵712100 [2]中国烟草总公司陕西省烟草公司,陕西西安710000 [3]西北农林科技大学植物保护学院,陕西杨陵712100

出　　处：《山西农业大学学报（自然科学版）》2024年第5期58-67,共10页Journal of Shanxi Agricultural University(Natural Science Edition)

基　　金：中国烟草总公司陕西省公司科技项目(KJ-2021-02);中国烟草总公司重大科技项目(110202101056(LS-16))。

摘　　要：[目的]本研究以烟草赤星病菌为靶标菌,筛选对其拮抗效果较好的生防菌,并对其进行后续的鉴定,同时初步设计试验验证生防机理,为烟草赤星病的拮抗生防菌资源、拮抗菌剂的制备等提供新的参考。[方法]采用初筛复筛获得生防菌后;绘制系统发育树鉴定、抑菌谱系测定、菌株产酶活性测定、对赤星病病菌菌丝生长和孢子萌发的影响、诱抗定量检测、离体叶片防效等方法验证生防机理。[结果](1)筛得2株对于赤星病菌拮抗效果较好的生防菌,经由16S rDNA鉴定发现其分别是枯草芽孢杆菌(Bacillus subtilis)X768与贝莱斯芽孢杆菌(Bacillus velezensis)703;并完成了2株生防芽孢杆菌的抑菌谱系测定,证明其均具有抑菌广谱性;(2)对其生防机理探究过程中,菌株703具备产生纤维素酶、蛋白酶和淀粉酶的能力,菌株X768具备产生纤维素酶、蛋白酶、淀粉酶和脂肪酶的能力;2株生防芽孢杆菌均可抑制赤星病孢子的萌发和影响菌丝正常生长的形态,对于病原菌具有较强的抑制作用;(3)使用qRT-PCR法验证了生防菌对烟草防御基因通路(SA、JA、ET等通路)的影响,其中应用菌株703处理后烟草应用防御通路可能与SA通路、JA通路和泛素连接酶通路相关;而使用菌株X768处理后烟草应用防御通路可能与SA通路和泛素连接酶通路相关。[结论]筛得的具有抑制烟草赤星病作用的生防菌株B.subtilis X768与B.velezensis 703,抑菌谱较广,均可较强效果地抑制赤星病孢子的萌发和菌丝生长,并且2株生防菌均可引起烟草防御基因通路的上调,离体叶片防效效果较好。[Objective]The purpose of this study was aimed to identify biocontrol agents with good antagonistic effects against Alternaria alternate.The research included preliminary testing of their biocontrol control mechanism to provide valuable insights into the development of biocontrol agents and resources against Tobacco scab.[Methods]Antagonistic bacteria were obtained through primary and secondary screening.The biological control mechanisms were verified using methods such as phylogenetic tree analysis,inhibition spectrum determination,enzyme activity measurement,effects on mycelial growth and spore germination of A.alternate,included resistance quantitative detection,and in vitro leaf protection efficacy.[Results]Two strains with good antagonistic effects against A.alternate were identified as Bacillus subtilis X768 and Bacillus velezensis 703through 16S rDNA sequencing.Both strains demonstrated broad-spectrum antibacterial activity.During the exploration of their biological control mechanisms,strain 703 was found to produce cellulase,protease,and amylase,while strain X768 produced cellulase,protease,amylase,and lipase.Both strains inhibited spore germination and affected the normal growth morphology of the pathogen's mycelium,showing strong inhibition effects.qRT-PCR analysis confirmed the impact of the antagonistic bacteria on tobacco defense gene pathways,including SA,JA,ET,etc.Treatment with strain 703 suggested possible invovlement of SA,JA,and ubiquitin ligase pathways in tobacco defense,while treatment with strain X768 indicated possible involvement of SA and ubiquitin ligase pathways.[Conclusion]The antagonistic strains B.subtilis X768 and B.velezensis 703,identified for their inhibitory effects against A.alternate exhibited broad-spectrum antibacterial activity,effectively inhibiting spore germination and mycelial growth of the pathogen.Both strains also upregulated tobacco defense gene pathways and showed good efficacy in in vitro leaf protection tests.

关 键 词：烟草赤星病 拮抗菌 生物防治 生防机理 

分 类 号：S432[农业科学—植物病理学]