一株烟草疫霉菌拮抗菌的筛选及应用潜力初探

Screening of an Antagonistic Strain of Phytophthora nicotianae and Its Application Potential

从烟草疫霉病发病严重的烟田取健康植株根系土壤,通过平板对峙法筛选对烟草疫霉菌有拮抗作用的菌株,获得1株对烟草疫霉菌有明显抑制作用的菌株LZW-118,平板抑制率达到71.14%。通过形态学特征、生理生化特征及16S rDNA序列分析,该菌株为越南伯克霍尔德氏菌(Burkholderia vietnamiensis)。促生潜力试验结果表明,该菌株对烟草疫霉的抑制作用显著,同时兼具溶磷固氮功能,能够提高烟草株高、叶长、叶宽、茎围、叶片数等农艺性状,具有较好的生物防治应用潜力。

Soil samples were taken from healthy tobacco plant rhizosphere in Phytophthora nicotianae severely infected tobacco field in Hunan to screen antagonistic strains against Phytophthora nicotianae by the plate confrontation method.Subsequently,we have obtained a strain LZW-118 that is of an obvious inhibitory effect on Phytophthora nicotianae with the plate inhibition rate of 71.14%.The strain LZW-118 is identified as Burkholderia vietnamiensis based on morphological,physiological and biochemical characteristics analyses and 16S rDNA sequence.The growth-promoting potential test results show that the strain not only has a significant inhibitory effect on Phytophthora nicotianae but also has the functions of nitrogen fixation,phosphorus dissolution and growth promotion for tobacco plant length,leaf length,leaf width and the number of leaves,showing a good application potential in biological control.