茶树内生真菌混合培养增强对植物病原真菌的拮抗作用

采用分离自健康茶树叶片组织中的2株内生真菌,长枝木霉CSN-18和曲霉CSN-3,研究了单独培养和混合培养条件下培养原液与培养原液乙酸乙酯萃取液对植物病原真菌的抑制作用。与2菌株单独培养相比,混合培养对稻瘟病菌Magnaporthe grisea、茶花褐斑病菌Phyllosticta camelliaecola和茶云纹叶枯病菌Guignardia camellia等8种植物病原真菌的抑制作用明显增强。混合培养原液的乙酸乙酯萃取液对茶花褐斑病菌、稻瘟病菌和茶云纹叶枯病菌的抑制率分别为79.48%±1.46%、76.99%±0.91%和71.51%±4.93%;对茶花褐斑病菌、茶云纹叶枯病菌和稻瘟病菌孢子萌发的抑制率分别为100.00%、90.90%±2.59%和84.00%±5.29%。混合培养原液对茶花褐斑病菌菌丝生长的抑制作用也比两菌株的单独培养液有明显增强;在低浓度下,混合培养原液对茶花褐斑病菌的孢子萌发有促进作用;但浓度超过40%,则明显抑制茶花褐斑病菌孢子的萌发。

Mixed culture of endophytic fungi isolated from Camellia sinensis enhancing the antagonistic on plant pathogenic fungi

Two endophytic fungal strains, Trichoderma longibrachiatum CSN-18 and Aspergillus sp. CSN-3, were isolated from healthy leaves of Camellia sinensis. The inhibitory activity against plant pathogenic fungi of these two fungi in the mixed culture was compared with monoculture. The results showed that the broth and its acetic ether extract of the mixed culture had much stronger inhibitions against Magnaporthe grisea, Phyllosticta camelliaecola, Guignardia camellia and other 5 species of plant pathogenic fungi as compared to monocultures of CSN-18 and CSN-3. The inhibition rates of acetic ether extract of the mixed culture to the mycelial growth of P. camelliaecola, M. grisea and G. camellia were 79.48%±1.46%, 76.99%±0.91% and 71.51%±4.93%, respectively. Inhibition rates of acetic ether extract of the mixed culture to the spore germination of P. camelliaecola, G. camellia and M. grisea were 100.00%, 90.90%±2.59% and 84.00%±5.29%, respectively. The broth of the mixed culture had a much higher inhibition rate to the mycelial growth of P. camelliaecola as compared to monocultures. Spore germination of P. camelliaecola was promoted by broth of the mixed culture in the concentration lower than 30%. But spore germination was dramatically inhibited when broth concentration was higher than 40%.