西瓜枯萎病拮抗链霉菌分离鉴定及盆栽抗病试验  

Isolation and Identification of Antagonistic Streptomyces spp. Against Fusarium Wilt of Watermelon and Primarily Potted Inhibition Test

作　　者：任迁琪 吴洪生[1] 李季[1] 陈素云[1] 徐亚[1] 姚东良[1] 赵月[1] 陈健[1] 李美颖[1] 宋星林 

机构地区：[1]南京信息工程大学农业资源与环境系,南京210044

出　　处：《生物技术通报》2016年第9期107-113,共7页Biotechnology Bulletin

基　　金：江苏省研究生培养创新工程项目(KYLX_0851);江苏省大学生实践创新计划(201310300065;1214071501136)

摘　　要：旨在筛选出能高效抑制西瓜枯萎病病原菌尖孢镰刀菌(Fusarium oxysporum f.sp.niveum)的天然拮抗菌。采用梯度稀释法分离连作辣椒根际土中的放线菌,纯化后用平板对峙法筛选出有拮抗作用的菌株,采用盆钵育苗基质拌菌法接种,进行盆栽抗病试验,并对拮抗效果最佳的菌株进行鉴定。结果显示,从连作辣椒根际土中,分离筛选出10株对西瓜枯萎病有拮抗作用的放线菌,其中菌株F22、F23、F32的拮抗作用显著。96 h抑菌圈直径分别达到1.70、1.17和1.47 cm。盆栽试验结果表明,拮抗菌株F32对西瓜枯萎病30 d的防治效果最佳,防效率达到66.7%,且抗菌谱性广。根据表型特征、生理生化特性和16S r DNA分子鉴定结果可知,菌株F32为链霉菌属(Streptomyces sp.),且对西瓜枯萎病有良好的防治作用,是一株具有应用价值的生防菌株。The objective is to select a natural antagonistic bacterium efficiently controlling Fusarium oxysporum f. sp. niveum that is the pathogenic bacterium of the fusarium wilt of watermelon. Using the method of gradient dilution to isolate aetinomycetes from rhizosphere soil of continuous cropping pepper, it was purified and the plate confrontation method was applied to select an antagonistic strain. Then the method of basin nursery substrates mixed with bacteria was for inoculation, a potted plant disease-resistant experiment was carried out, and the strains with the optimal antagonistic effects were identified. The results showed that 10 strains of actinomyeetes with the antagonistic effects to fusarium wilt of watermelon were isolated from the growing pepper rhizosphere soil, and 3 of them （ F22, F23 ＂and F32 ） presented the significantly antagonistic effects. After 96 hours the diameter of the inhibition zone was 1.70 cm, 1.17 cm and 1.47 cm respectively. The result of the potted plant experiments demonstrated that the control effect of the antagonistic strain F32 to the fusarium wilt of watermelon reached maximum with 66.7% at 30 d, moreover, it also had a wide antibacterial spectrum. Based on the phenotypic characteristics, physiological-biochemical characteristics, and the results of 16S rDNA molecular analysis, the F32 was identified as Streptomyces sp., and F32 presented solid control effects on the fusarium wilt of watermelon, thus it is biocontrol strain with potential application value.

关 键 词：西瓜枯萎病 尖孢镰刀菌 拮抗菌 生物防治 

分 类 号：S436.5[农业科学—农业昆虫与害虫防治]