柑橘内生菌的分离、鉴定及其对沙皮病的防治作用  

Screening and Identification of Citrus Endophytic Bacterium for Biocontrol of Sandpaper Russet

作　　者：刘胜贵[1] 周玉莎[1,2] 易江[1] 魏麟[1] 邹娟[1] 

机构地区：[1]怀化学院生物与食品工程学院民族药用植物资源研究与利用湖南省重点实验室,中国湖南怀化418008 [2]华中农业大学生命科学技术学院,中国湖北武汉430070

出　　处：《生命科学研究》2016年第5期429-434,共6页Life Science Research

基　　金：湖南省教育厅科研项目(11C0988)

摘　　要：为测定柑橘内生菌体外抑菌活性及对柑橘沙皮病的防治效果,从湖南麻阳县采集冰糖橙、椪柑、脐橙样本,分离内生菌,通过平板对峙培养法筛选出对柑橘拟茎点霉菌(Phomopsis citri)拮抗作用最强的菌株X17;根据形态学特征、生理生化特征及16S rDNA基因序列分析,确定其分类地位;随后,分别于坐果抗逆期和壮果增糖期向田间果树喷洒不同稀释度的发酵液,研究其生防效果。结果显示,X17菌株对柑橘拟茎点霉菌抑菌圈半径达到11 mm,抑菌率达到55%;同时,鉴定实验初步判定该菌株为解淀粉芽孢杆菌(Bacillus amyloliquefaciens);此外,田间实验结果表明其发酵液对叶片感染的沙皮病有明显防治效果。上述结果说明,X17菌株对冰糖橙、椪柑、脐橙沙皮病具有较显著的防治作用,是一株有开发潜力的生防菌。The present investigation focused upon isolation and selection of endophytic bacterial strains from citrus and evaluation of their inhibitory activity in vitro and biocontrol efficacy against sandpaper russet. Ap- parently healthy Citrus sinensis, C. reticulata cv. Ponkan and C. sinensis cv. navel oranges were collected from the major citrus-growing locales in Mayang County, Hunan Province, respectively. With the aid of the plate-confrontation method, the endophytic bacterium X17 with the greatest antagonistic effect against Pho- mopsis cirri was selected. The strain was classified and identified by morphological traits, physiological-bio- chemical characteristics, and sequencing of 16S rDNA gene and analysis of sequences similarity in Gen- Bank. During the fruit-setting period and the sugar accumulation period, aerial parts of the citrus from or- chard were inoculated with suspensions containing the antagonistic endophyte as biological control agent. The results showed that inhibition zone radius formed by strain XI7 against P. citri was up to 11.0 mm in vitro and the inhibition ratio was 55%. What＇s more, the application of suspensions containing the strain X17 exhibited significant effects of controlling sandpaper russet on the leaves in field condition. Herein, the strain X17 was initially identified as Bacillus amyloliquefaciens. It would be a promising biological control agent against the phytopathogenic fungus P. citri.

关 键 词：内生菌 柑橘沙皮病 解淀粉芽孢杆菌 拮抗作用 生物防治 

分 类 号：S562[农业科学—作物学]