荧光假单胞菌拮抗菌株对烟草疫霉的抑菌机制及控病效果  

Antagonistic mechanism of Pseudomonas fluorescens strains against Phytophthora nicotianae and biocontrol effect on tobacco black shank

作　　者：董国菊[1] 马冠华[1] 肖崇刚[1] 

机构地区：[1]西南大学植物保护学院,重庆400716

出　　处：《植物保护学报》2012年第2期115-120,共6页Journal of Plant Protection

基　　金：重庆市自然科学基金(2008BB1249);中央高校基本科研业务费专项资金(XDJK2009C177)

摘　　要：为探讨烟草根际生防细菌对烟草疫霉Phytophthora nicotianae的抑菌机制,从重庆地区连作烟田健康烟株根际土壤分离获得5株荧光假单胞菌Pseudomonas fluorescens拮抗菌株。通过平板对峙及代谢产物抑菌试验筛选对烟草疫霉具有高效拮抗作用的菌株,其中,P-72-10菌株抑菌效果最强,抑菌带半径达13.0 mm,相对抑制率为68.57%,且该菌株代谢产物对烟草疫霉菌丝生长有明显的抑制作用,相对抑制率达25.39%～46.03%;显微观察发现该菌株可引起烟草疫霉菌丝的分支增多,菌丝顶端膨大呈畸形,多数菌丝中间或顶端细胞的细胞壁加厚、原生质浓缩和产生类似厚壁孢子的细胞。在温室盆栽条件下P-72-10菌株对烟草黑胫病也表现出良好的控病效果,对抗病和感病品种的相对防效分别为53.57%和66.37%。To explore the antagonistic mechanism of rhizospheric bacteria against Phytophthora nicotianae van Breda de Haan,five antagonistic Pseudomonas fluorescens strains were isolated from rhizospheric soils of tobacco fields in Chongqing.Efficient antagonistic strain against P.nicotianae was screened using dual culture technique and metabolites inhibitory test.Among these strains,P-72-10 showed the highest suppressive effect;it produced an inhibition zone of 13.0mm（radius） and an inhibitory rate at 68.57%.Furthermore,the growth of pathogen＇s hypha was also suppressed by the extracellular metabolites of strain P-72-10 from 25.39% to 46.03%.P.nicotianae was observed microscopically excessive branching of mycelia and malformation of mycelia tips;thick-walled cells with concentrated plasmas and chlamydospore-like cells.When tested on the tobacco plants grown in greenhouse,strain P-72-10 got a good biocontrol effect on tobacco black shank infection and effects on the resistant and susceptible varieties of tobacco were 53.57% and 66.37% respectively.

关 键 词：荧光假单胞菌 烟草疫霉 抑菌机制 烟草黑胫病 控病效果 

分 类 号：S435.72[农业科学—农业昆虫与害虫防治]