拮抗细菌B-916培养液对水稻纹枯病菌的抗生活性及其抗菌物质的研究

On Antagonism against Rhizoctonia solani of Culture Solution of Strain B 916 and Constituent of Its Antifungal Substance

拮抗细菌 B- 91 6培养液从原液至稀释 40 0倍的稀释液对水稻纹枯菌的生长均有抑制作用 ,且浓度愈高 ,抑制作用愈强。培养液原液与纹枯菌对峙培养 ,形成的拮抗带宽度为 6 .7m m。用培养液处理 Rhizoctonia solani,菌核形成比未经 B- 91 6培养液处理的纹枯病菌 (对照 )推迟 5 2 h。把 B- 91 6培养液喷雾在水稻植株上能有效控制纹枯菌的侵染、蔓延 ,防治效果达 5 8.1 %。 B- 91 6培养液用 80 %饱和度的硫酸铵沉淀后透析 ,上清液完全丧失了抑菌作用 ,沉淀部分对纹枯菌的抑菌作用比未经硫酸铵处理的 B- 91 6培养液 (对照 )显著增强。由培养液对蛋白酶的敏感性试验结果推测 ,拮抗菌 B- 91

Antagonistic bacteria B 916 at the dilution rate from 0 to 400 times was efficacious against Rhizoctonia solani .The higher the concentration of B 916 was,the better the efficiency was.After R.solani was treated with crude culture solution of B 916,an antagonistic band about 6 0 mm was observed and formation of sclerotia of R.solani was delayed for 52 h.Control effect of B 916 culture solution on R.solani reached 58 1%.After the culture solution of B 916 was precipitated with(NH 4) 2SO 4(saturation degree:80%) for 24 h,the supernatant lost the inhibition to R.solani ,and the inhibition of precipitate was stronger than that of B 916 culture solution without (NH 4) 2SO 4 treatment.From the experiment on the susceptibility of B 916 culture solution to proteinase,it could be referred that major constituent of antifungal substance in culture solution of B 916 was protein.