黄瓜枯萎病菌内生拮抗细菌的筛选与鉴定

采用平板对峙法从黄瓜体内筛选对黄瓜枯萎病菌具有拮抗作用的细菌.结果表明,黄瓜体内的细菌数量为2.9-25.6×103cfu· (g·FW)-1,其中,植株不同器官的内生细菌数量不同,以叶中的细菌数量最多,其次为花,最少的为果实；从所分离的细菌菌株中筛选到20株对黄瓜枯萎病菌具有不同程度拮抗作用的菌株；选择拮抗效果较好的10株菌株,用革兰氏染色、鞭毛染色、芽孢染色和生理生化测定等进行鉴定,发现其均为芽孢杆菌属(Bacillus spp.).

Screening and identification of the antagonistic and endophtic bacteria to Fusarium oxysporum f.sp. cucumerinum

Strains isolated from cucumber were screened for antagonizing to the pathogen Fusarium oxysporum f.sp.cucumerinum by pairing culture.The results showed that the population numbers of the bacteria isolated from the different parts of cucumber plant were different,about 2.9-25.6×103 cfu · g^-1fresh weight）.The leaves had the largest number,followed by the flowers,and the fruit samples had the least.In addition,twenty isolates were found to have inhibitory activity to the pathogen.Among the 20 strains,10 strains,with a stronger antagonistic ability to the pathogen and to some other fungal pathogens,were screened.The 10 strains were all identified as to be Bacillus spp.based on the results of Gram,flagella,spore stains and the physiological and biochemical tests.