枯草芽孢杆菌对棉花枯、黄萎病的抑制作用研究

【目的】研究枯草芽孢杆菌(Bacillus subtilis)生物学特性,测定枯草芽孢杆菌对棉花枯萎病菌和黄萎病菌的抑菌效果,对枯草芽孢杆菌的抑菌机理进行初步研究。【方法】菌丝生长速率法,平极对峙培养法,定期观察和显微镜法。【结果】枯草芽孢杆菌对温度和酸碱度的适应范围广,营养条件与枯黄萎病菌菌丝生长需要一致;棉花枯萎病菌培养至第7 d时,抑菌效果为88.8%,棉花黄萎病菌菌丝培养至20 d时,抑菌效果为86.5%;该菌对枯黄萎病菌具有明显的营养竞争和空间竞争作用,可以溶解致菌菌丝和导致菌丝畸形。【结论】该菌是一种适应性较强的微生物,枯草芽孢杆菌对棉花枯萎病菌和黄萎病菌具有明显抑制作用,枯草芽孢杆菌可用于新疆地区棉花枯萎病菌和黄萎病的防治。

Studies on the Control of Bacillus Subtilis on Cotton Fusarium Wilt and Cotton Verticillium Wilt

By the mycelium growth speed rate methods,the study on biological characteristics of Bacillus subtilis showed that it was of wide adaptability for temperature and pH value,and its nutrient condition had similarity with the need for the mycelium growth of cotton fusarium wilt and cotton verticillium.Bacillus subtilis was obviously antagonistic to two pathogens by dual culture method.The inhibitory efficiencies reached 88.8% after 7days against cotton fusarium wilt,and 86.5% after 20 days against cotton verticillium wilt.In addition,the control mechanism of Bacillus subtilis was initially researched,and the results showed that the distinct competition on nutrient and space exsited between Bacillus subtilis and the pathogens.Microscopically observed,this antagonistic bacterium could dissolve mycelium and make it deformity.Control of Bacillus subtilis on cotton fusarium wilt and cotton verticillium wilt were initially determined indoors,the results showed that: the control of Bacillus subtilis on cotton fusarium wilt and cotton verticillium wilt were evident.