苹果树腐烂病生防链霉菌A144的鉴定及其代谢产物的抑菌活性

旨在明确菌株A144的分类地位及其代谢产物的抑菌活性。基于形态学观察、生理生化特征以及16S rDNA序列分析将菌株A144鉴定为娄彻氏链霉菌(Streptomyces rochei)。采用含药平板法测定菌株A144的抑菌谱，结果表明其发酵滤液对苹果树腐烂病菌(Valsamali var.mali)、西瓜枯萎病菌(Fusarium oxysporum)、水稻恶苗病菌(Fusarium moniliforme)以及番茄早疫病菌(Alternaria solani)均有抑菌活性，抑菌率分别为68.15%±2.62%、28.90%±1.79%、33.77%±2.59%和11.43%±0.81%。以苹果树腐烂病菌为指示菌，从12种不同培养基中筛选出ISP2培养基为菌株A144的最佳发酵培养基，其发酵滤液的抑菌率达85.06%±0.86%。平板涂抹法和平板对扣法试验结果表明，其脂肽粗提物、蛋白粗提物和挥发性物质对苹果树腐烂病菌均有抑菌活性，抑菌率分别为81.44%±0.92%、47.92%±2.25%和22.87%±4.40%。可见，菌株A144在苹果树腐烂病的生物防治中具有良好的开发潜力。

Identification of Biocontrol Streptomyces A144 against Apple Tree Valsa Cancer and Antifungal Activity of Its Metabolites

In order to clarify the taxonomic status of strain A144 and study the antifungal activity of its metabolites, strain A144 was identified as Streptomyces rochei based on morphological observation, physiological and biochemical characteristics and 16S rDNA sequence. The antifungal spectrum of strain A144 was determined by the drug containing plate method. The results showed that its fermentation filtrate had antifungal activity against Valsa mali var. mali, Fusarium oxysporum, Fusarium moniliforme and Alternaria solani, and the inhibition rates were 68.15%±2.62%, 28.90%± 1.79%, 33.77%±2.59% and 11.43%±0.81%, respectively. Using Valsa mali var. mali as indicator pathogen, ISP2 medium was selected as the best fermentation medium of strain A144 from 12 different media. The inhibition rate of its fermentation filtrate was 85.06%±0.86%.The results of plate smear method and plate buckle method showed that its crude lipopeptide, crude protein and volatile substances had antifungal activity against Valsa mali var. mali, and the inhibition rates were 81.44%±0.92%, 47.92%±2.25% and 22.87%±4.40%, respectively. The results showed that strain A144 has good development potential in the biological control of apple tree valsa cancer.