土壤拮抗细菌的分离与抗植物病原真菌活性初步研究

Preliminary Study on Isolating Antagonistic Bacteria from Soil and Antagonistic Activity Against Plant Pathogens

为了分离筛选出土壤中对植物病原真菌具有拮抗作用的细菌,以4种土传病害病原菌为诱导菌株,采用土壤颗粒撒布法,从不同生态区农田土壤样本中分离得到55株拮抗细菌菌株。测定了部分拮抗菌株及发酵滤液对植物病原菌的拮抗作用。结果表明:分离获得的细菌菌株对病原真菌均表现出一定程度的抑制作用,其中对菜豆根腐病菌(Fusarium solani)、小麦赤霉病菌(Fusarium graminearum)、番茄枯萎病菌(Fusarium oxysporum)菌丝抑制率达60%以上的拮抗菌株,分别有1、12和8株。9株拮抗菌发酵滤液对大豆菌核病菌(Sclerotinia sclerotiorum)、水稻稻瘟病菌(Pyricularia grisea)、玉米大斑病菌(Setosphaeria turcica)、小麦根腐病菌(Bipolaris sorokiniana)、水稻恶苗病菌(Fusarium moniliforme)和马铃薯早疫病菌(Alternaria solani)6种植物病原菌表现出较高的抑菌效果,其中YS7菌株发酵产物对玉米大斑病菌、小麦根腐病菌、水稻恶苗病菌均表现较强的抑菌活性,对玉米大斑病菌抑菌圈直径最大达到了56.2mm。从抗菌谱上看,27株拮抗菌株代谢产物对4种以上的拮抗对象表现有抑菌活性,表明拮抗菌株代谢产物具有较为广谱的抑菌效果。

In order to screen antagonistic bacteria in soil for plant pathogens bio-controL 55 antagonistic bacteria strains were isolated from soil samples in different ecological regions by the soil sprinkling method baited with 4 soil borne diseases. Part of antagonistic bacteria strains were evaluated for the antagonistic activity against plant pathogens. The result showed that more than 60 ; mycelial inhibition against Fusarium solani,Fusarium graminearum,Fusarium oxysporum were 1,12 and 8 stains,respectively. Fermentation filtrate of 9 antagonis- tic bacteria strains showed higher inhibition effect for Sclerotinia sclerotiorum, Pyricularia grisea, Setospha- eria turcica , Bi polaris sorokiniana , Fusarium monili f orme and Alternaria solani , the fermentation products of YS7 strain showed strong antifungal activity to Setosphaeria turcica ,Bipolaris sorokiniana ,Fusarium rnonili- forme ,the diameter of inhibition zone reached a maximum of 56.2 mm against Setosphaeria turcica. Metabo- lites of 27 antagonistic bacteria strains showed inhibition activity to more than 4 antagonistic objects,it showed that the fermentation products of antagonistic bacteria strains had broad-spectrum antifungal activity.