摘要
用稀释平板法和诱饵法从西南四省区（川、云、贵、藏）不同生态环境的土壤和其它材料分离到170株木霉。稀释平板法从57％的土样分离到木霉,大大高于用诱饵法的10.8％。诱饵法更易受到毛霉、根霉等土壤速生真菌的影响。土壤分离结果表明,从气候炎热的西双版纳到海拔3500～5500米的西藏高原,在土壤pH值为4.0～8.0范围内的各种土壤中均分离到木霉,而从植被差、贫瘠的土壤中很难分离到木霉。 用玻璃纸对峙法观察了不同来源的木霉菌株与棉苗立枯菌菌丝间的交互反应,从不同类型土壤和其它材料获得的木霉中都有与立枯丝核菌发生交互反应的,不过桔抗木霉的频度不相同。从农耕土壤分离到的木霉中53％的对棉苗立枯病菌有拮抗作用;其次为森林草原土壤,为40％;从玉米籽粒、朽木、食用菌培养料等分离到的木霉,有20％有轻度桔抗作用。
170 isolates of Trichoderma spp. were obtained from the soils under various ecological conditions and other materials (e. g. rotten wood, corn seeds and food mushroom) in the four provinces of southwestern China. Each soil sample was treated using two methods, i. e. serial soil dilution plate and baiting techniques.Trichoderma spp. were derived from 57% of soil samples by serial soil dilution much higher than 10.8% by baiting technique, with the isolation being more easily affacted by the soil fungi Mucor spp. and Rhizopus SPP. while baiting technique was adopted. The results from isolation indicate that Trichoderma spp. could be obtained from all soils (pH 4.0-8.0) in the vast land extending from Xishuangbanna with a hot and rainy climate to the Tibet with a cold and dry climate (3500-5500m above sea level) . However, they were hardly isolated from poor soils.The hyphal interactions between Trichoderma spp. and Rhizoctonia solani derived from cotton seedlings were observed in vitro with a cellophane membrance method. Although all Trichoderma isolates with different origin have shown the antagonistic action against the pathogen of cotton seedling damping-off , the rate of antagonistic isolates were 53%, 40% and 20% respectively in cultivated soil, forest and pasture soil and other materials.
出处
《西南农业学报》
CSCD
1990年第2期53-56,共4页
Southwest China Journal of Agricultural Sciences
关键词
棉花
苗期
立枯病
防治
木霉
Cotton, Trichoderma spp, Rhizoctonia solani
