Colletotrichum gloeosporioides is a main cause of rubber anthracnose, which results in a huge loss for the natural rubber industry. In this study, an actinomycete strain QY-3 was isolated and had good antagonistic activity against C. gloeosporioides with an inhibition rate of 86.6%. Strain QY-3 was identified as Streptomyces deccanensis preliminarily. Millet medium was selected as the optimal fermentation broth for antifungal metabolites production by S. deccanensis QY-3. The culture filtrate extract (CFE) from the millet broth of S. deccanensis QY-3 exhibits broad-spectrum antifungal activity against plant pathogenic fungi, and its EC₅₀ inhibiting the mycelial growth of C. gloeosporioides is 6.3 μg/mL. The CFE has good thermal and pH stabilities, and it can break the hyphae and inhibit the conidial germination of C. gloeosporioides. 100 μg/mL of CFE had an obvious control effect on rubber anthracnose, and the control efficacy was 63.7% on 5 days after inoculation. Two compounds with inhibitory effects on C. gloeosporioides, anthranilic acid and sangivamycin, were isolated from the CFE. The MICs of both compounds against C. gloeosporioides were 29.3 and 23.0 μg/mL respectively. In conclusion, the CFE from S. deccanensis QY-3 has great potential to be a promising fungicide for rubber anthracnose.

炭疽菌是橡胶炭疽病的主要原因，这导致天然橡胶工业的巨大损失。在这项研究中，放线菌菌株QY-3被分离出来，并具有良好的拮抗球孢梭菌的活性，抑制率为86.6％。菌株QY-3初步被鉴定为 癸链霉菌。选择小米培养基作为S. deccanensis QY-3生产抗真菌代谢物的最佳发酵液。S.deccanensis QY-3谷子肉汤的培养物滤液提取物（CFE）对植物病原真菌具有广谱抗真菌活性，其EC ₅₀抑制木霉菌丝体的生长。球孢梭菌为6.3μg/ mL。CFE具有良好的热稳定性和pH稳定性，并且可以破坏菌丝并抑制球孢梭菌的分生孢子萌发。100μg/ mL CFE对橡胶炭疽病具有明显的防治效果，接种5天后防治效果为63.7％。从CFE中分离出两种对球孢梭菌具有抑制作用的化合物，邻氨基苯甲酸和桑格霉素。两种化合物对球孢梭菌的MIC分别为29.3和23.0μg/ mL。总之，来自S.deccanensis QY-3的CFE具有很大的潜力，有望成为橡胶炭疽病的有希望的杀菌剂。