李苗苗 张家韬 崔传斌 孙光军 王东坤 崔志燕 高强 冯超 王凤龙 陈德鑫 王晓强

摘  要：为明确贝莱斯芽孢杆菌（Bacillus velezensis）GY1、解淀粉芽孢杆菌（Bacillus amyloliquefaciens）GY10和枯草芽孢杆菌（Bacillus subtilis）GY12的生防特性，采用平板试验法、对扣法、盆栽试验等，对三株生防菌的抑菌谱、次生代谢产物、挥发性物质、根际定殖能力和促生能力等进行了研究。结果表明，GY1、GY10、GY12培养液可以显著促进烟草种子的萌发和烟株的生长;三株生防菌抑菌谱广，对烟草赤星病菌、黑胫病菌及花生镰刀菌等9种病原具有显著的抑制作用，并且都具有分泌嗜铁素和蛋白酶的能力;三株生防菌发酵上清液和挥发性物质对链格孢菌（Alternaria alternata）和烟草疫霉菌（Phytophthora parasitica var. nicotianae）具有显著抑制作用;菌株的分泌蛋白热稳定性好，对烟草赤星病菌具有显著的体外抑菌活性，并对酸性环境具有较高的耐受性;根际定殖结果表明，GY1-GY10-GY12复配与单菌株相比能增加各生防菌在烟草根际的定殖。以上结果对于菌株GY1、GY10、GY12生防特性的深入挖掘和产业化开发具有一定的指导作用。

关键词：芽孢杆菌;烟草黑胫病;烟草赤星病;生防特性;根际定殖

Abstract： In order to clarify the biocontrol characteristics of Bacillus velezensis GY1， Bacillus amyloliquefaciens GY10， and Bacillus subtilis GY12， antibacterial spectrum， secondary metabolites， volatile substances， rhizosphere colonization ability and growth-promoting ability of the strains were studied by compatible test， double petri dish assay and pot test. The results showed that GY1， GY10， and GY12 can significantly promote seed germination and growth of tobacco. The three strains have a broad antimicrobial spectrum and have significant inhibitory effects against Alternaria alternata， Phytophthora parasitica var. nicotianae and Fusarium spp. In addition， all of the tree strains have the ability to produce siderophore and protease. The fermentation supernatants and volatile substances of the three strains also have a significant inhibitory effect against A. alternata and P. parasitica var. Nicotianae. The secreted proteins of the strains have good thermal stability and significant in vitro antibacterial activity on A. alternata， and have high tolerance to acid environments. The results of rhizosphere colonization assay indicated that GY1-GY10-GY12 compounding could increase the colonization of each biocontrol bacteria in the tobacco rhizosphere compared with a single strain. The resuls from this study provide guidance for in-depth exploration of the biocontrol characteristics of strains GY1， GY10， and GY12 and the industrial development of biocontrol strains.

Keywords： Bacillus spp.; Phytophthora parasitica; Alternaria alternata; biocontrol mechanism; rhizosphere colonization

生物防治是利用有益微生物或其代謝产物对植物病害进行防治的技术，因其具有绿色、安全、防效持久，不污染环境等特点在农业生产中逐渐被应用。烟草生育期内会被很多病害侵染，如由烟草疫霉菌（Phytophthora parasitica var. nicotianae）引起的烟草黑胫病及由链格孢菌（Alternaria alternata）引起的烟草赤星病[1-2]。目前，生产上对该类病害的防控主要依靠化学药剂，但是长期大量施用会对环境以及人类健康造成严重危害，因此生物防治成为烟草病害防控的重要措施之一[3]。……