机构地区: 华南农业大学资源环境学院
出 处: 《中国生物防治学报》 2013年第2期270-276,共7页
摘 要: 从不同土壤、植物和水稻纹枯病菌Rhizoctonia solani菌核样品上分离到细菌菌株325株和放线菌菌株86株。通过琼脂平板对峙法及发酵滤液介质筛选法,获得了对水稻纹枯病菌具有较强拮抗活性的细菌和放线菌菌株各1株,它们对水稻纹枯病菌菌丝生长的抑制率分别为75.56%和84.07%。采用形态学和生理生化学以及分子生物学方法,将细菌菌株NB12鉴定为枯草芽胞杆菌Bacillus subtilis、放线菌菌株NA1鉴定为Streptomyces triostinicus。对它们产生抑菌物质的发酵条件进行了探索,明确了菌株NB12的最佳发酵条件为:初始pH 7.0的LB或BPY培养液、装液量40 mL/250 mL、培养温度30℃、摇床转速180 r.min 1、培养时间48 h;菌株NA1的最佳发酵条件为:初始pH 6.0~9.0的大豆粉培养液或大豆粉–玉米粉培养液、装液量130 mL/250 mL、培养温度35℃、摇床转速140 r.min 1、培养时间≥72 h。 Three hundred and twenty five bacterial strains and eighty six actinomycete strains were isolated from the samples taken from different soils, plants and Rhizoctonia solani sclerotia. One bacterial and one actinomycete strains with strong antagonistic activities to R. solani were selected by using both agar plate dual culture and fermentation filtrate-amended medium screening methods. Their inhibition rates to mycelial growth of R. solani were 75.56% and 84.07%, respectively, on the two medial plates. Based on morphological, physiological, biochemical and molecular characteristics, NB12 was identified as Bacillus subtilis, and NA1 as Streptomyces triostinicus. The cultivation conditions for antifungal substance production by NB 12 were: LB or BPY medium at initial pH 7.0, culture volume at 40 mL/250 mL flask, incubation temperature at 30 ℃, and shaking rate at 180 r.min-1 for 48 h; whereas those for NA1 were: soybean or soybean-corn powder liquid medium at initial pH 6.0- 9.0, culture volume at 130 mL/250 mL flask, incubation temperature at 35 ℃, and shaking rate at 140 r-min-1 for 72 h or above.