抑制黄瓜蔓枯菌的放线菌筛选

Screening of Antagonistic Actinomyces on Ascochyta citrullina

以黄瓜蔓枯菌为指示菌,采用平板稀释法和对峙法获得拮抗放线菌菌株9株,并以常见的10种蔬菜病原菌为目标菌进行复筛,发现菌株A9、T111拮抗谱较宽,对黄瓜蔓枯菌(Ascochyta citrullina Smith)、黄瓜枯萎菌(Fusarium.oxysporum)、黄瓜菌核((Sclerotinia scleotiorum)等有很好的抑制作用,并具有产几丁质酶的能力。经形态、培养特性等初步鉴定为链霉菌属(Streplomyces)不同类群。A9、T111发酵液在病原菌活体定植抑制测定试验中,对黄瓜蔓枯病菌抑制效果分别达56.7%和65.4%。

Using confronted culture method in dilute microbe we had separated 9 strains of antagonistic actinomyces on Ascochyta citrullina, which screened again on 10 common pathogens of vegetable we discovered the strain A9 and T111 with ehitinolytie ability had strong and stable antagonistic capacities against Ascochyta citrullina Smith, Fusarium. oxysporum. , Sclerotinia seleotiorom et al. They were identified as Streptomyces based on their morphology and cultural characters. The controlling rate of the strains A9 and T111 to Ascochyta citrullina when treatment of cucumber seedling with these ferment solution in greenhouse reached respectively 56.7% and 65. 4% as compared with the CK.