将两种抗病机制结合控制桉树青枯病的研究  

Control of Eucalypt Bacterial Wilt by Combination of Two Different Suppression Mechanisms

作　　者：冉隆贤[1] 向妙莲[2] 李正楠[1] 姬惜珠[1] 

机构地区：[1]河北农业大学,河北保定071001 [2]江西农业大学,江西南昌330045

出　　处：《中南林业科技大学学报》2008年第4期87-91,共5页Journal of Central South University of Forestry & Technology

基　　金：国家自然科学基金项目(30471396);国家“十一五”林业科技支撑计划项目(2006BAD08A1102)

摘　　要：以对桉树青枯病有防治效果的荧光假单胞杆菌(Pseudomonas fluorescens)WCS417r为对照,用水杨酸和产生PCA抗生素(phenazine-1-carboxylic acid)的荧光假单胞杆菌(P.fluorescens)2-79进行了桉树青枯病防治试验,并在此基础上,将水杨酸与2-79、WCS417r分别组合,将诱导抗病性和抗生作用结合起来共同控制桉树青枯病的发生.盆栽试验结果表明,采用菌液蘸根的方法,2-79和WCS417r分别比对照的发病率降低18.4%和33.8%,差异显著(α=0.05).在组合防病试验中,经水杨酸、2-79、WCS417r分别处理后的桉树苗发病率分别比对照降低37.2%、42.9%和37.2%,而用水杨酸和生防菌共同处理(SA+2-79,SA+WCS417r)后的发病率则比对照分别低54.3%、51.5%,且比分别用三者单独处理的显著降低,防病效果显著增强.此结果表明,水杨酸的诱导抗病性与具有拮抗活性的生防菌结合,能显著提高防治桉树青枯病的效果.Bioassays were performed to control bacterial wilt in Eucalyptus urophylla by salicylic acid （SA）, Pseudornonas fluorescens strain 2-79 which produces phenazine-1-carboxylic acid （PCA） using P. fluorescens strain WCS417r as a positive control. Based on these, experiments were designed to suppress eucalypt bacterial wilt by combination of salicylic acid and either of strains 2-79 or WCS417r, in which salicylic acid suppressed eucalypt bacterial wilt by induction of systemic acquired resistance, and 2-79 controlled this disease by its antagonistic activity. The percentages of wilted seedlings were significantly decreased when salicylic acid at 0. 5 mmol was applied by root dipping for 5 days before they were transferred to infected potting soil with Ralstonia solanacearum. The control effects on bacterial wilt by strain 2-79 and WCS417r were tested by dipping roots of seedling in bacterial suspension, followed by transferring, them to infected potting soil with R. solanacearum at 5 × 10^7CFU · gasoil. Both strains of 2-79 and WCS417r reduced the percentages of wilted seedlings by 18. 4% and 33.8%, respectively, which was significant compared with that of the control （a= 0. 05）. In the combination test, the treatment with SA, strain 2-79 or WCS417r alone, decreased the percentages of wilted seedlings （PWS） by 37.2%, 42.9% and 37.2%, while the combination of SA plus PCA-producing strain 2-79 or SA with positive control WCS417r significantly reduced PWS by 54.3 % and 51.5 % compared with the control, respectively （α= 0. 05）. These results demonstrated that combination of two different suppressive mechanisms, such as induction of systemic acquired resistance and antibiosis, could strongly enhance the control effects against eucalypt bacterial wilt.

关 键 词：生物科学与工程 病理学 尾叶桉 荧光假单胞杆菌 PCA 青枯菌 水杨酸 

分 类 号：S763.70[农业科学—森林保护学] S792.39[农业科学—林学]