放线菌WZ1-5019的鉴定及其发酵液对香蕉黑星病的田间防治效果试验

放线菌WZ1-5019菌株是从海南五指山原始森林土壤中分离筛选得到的一株对香蕉黑星病菌具有强烈抑制作用的生防菌,其发酵液无菌滤液亦对香蕉黑星病菌具有较强抑菌活性。根据形态观察、培养特征、生理生化鉴定及16S rDNA序列分析,初步鉴定为链霉菌属中的Streptomyces costaricanus。香蕉黑星病是香蕉的重要病害之一,至今尚无生物农药用于香蕉黑星病的防治,本试验采用链霉菌WZ1-5019菌株发酵液进行香蕉黑星病田间防治试验,结果表明,施用链霉菌WZ1-5019菌株发酵液3次后,对香蕉黑星病的平均防治效果达81.68%,显著优于30%爱苗乳油1 500倍液防效(59.96%)和10%世高水分散粒剂1 500倍液防效(53.58%),具有开发成香蕉黑星病生物农药的前景。

The Identification of Actinomycetes Strain WZ1-5019 and the Field Control Effect Tests of the Fermented Liquid on Banana Freckle Disease

The Actinomycetes strain WZ1-5019 is a biological control agent which has strong inhibitory effects on Macrophoma musae from the virgin forest soil of Five-finger Mountain Natural Reserve of Hainan Province, China. Moreover, its filtrate of fermentation liquid has strong inhibitory effects on Macrophoma musae. Based on the results of morphological, physiological, chemotaxonomic characteristics and 16S rDNA sequence analysis, the strain WZ1-5019 was placed within the genus Streptomyces and classified as the species Streptomyces costaricanus. Banana freckle disease is one of the main diseases of Musa, there is no a biological pesticide reported for the controlling of banana freckle disease to date. The results of the present tests in fields showed that the filtrate of fermentation liquid of the Streptomyces strain WZ1-5019 for 3 times had exerted an average control effect up to 81.68% against banana freckle disease, significantly better than that treated with 30% Armure EC 1 500 times dilution(59.96%)and 10% difenoconazole 1 500 times dilution(53.58%), and thus had application potential to be used as a biological pesticide against banana freckle disease.