茄子黄萎病生防内生细菌的筛选、鉴定及胞外抗菌物质的特性

Selection and Identification of a Biological Control Endophytic Strain of Eggplant Verticillium Wilt and Characterisics of Its Extracellular Antifungal Metabolites

对分离筛选获得的6株对茄子黄萎病菌Verticillium dahliae具有强拮抗活性的内生细菌进行盆钵防效测定,其中3个菌株29-122、2-5和0-21对茄子黄萎病防治效果均在80%以上。对菌株29-12和22-5进行内生定殖能力检测,发现菌株29-12在茄子体内定殖时间更长。经鉴定,菌株29-12为枯草芽孢杆菌Bacillus subtilis。菌株29-12能产生抗茄子黄萎病菌的胞外活性物质。该活性物质对热较稳定;pH6.0~9.0时活性稳定,pH【4.0时没有活性;对蛋白酶K和胰蛋白酶都不敏感。抑菌谱测定表明,该物质对10种病原真菌均有较强的抑制作用。

Six endophytic bacterial strains isolated from the interior of eggplant stems had strong antifungal activity against Verticillium dahliae. In pots experiments,strains 29-12,22-5 and 0-21 had high control effect on eggplant Verticillium wilt.Through colonization assay of the strains 29-12 and 22-5,strain 2912 colonized in eggplant longer than strain 22-5.Strain 29-12 was identified as Bacillius subtilis.The crude metabolite produced by strain 29-12 had strong antifungal activity against V.dahliae.The crude metabolite was stable to heat,trypsin and proteinase K digestion,pH(6.0-9.0) treatment.The crude metabolite demonstrated strong antifungal activity against 10 fungal pathogens.