植物内生放线菌Lj20发酵液萃取物对真菌作用*机理的研究

Study on antifungal mechanism of endophytic actinomyce Lj20 extracts

【目的】明确植物内生放线菌Lj20发酵液萃取物对真菌的抑菌作用机理。【方法】观察100 mg/LLj20萃取物对灰葡萄孢菌菌丝形态的影响,测定0.02,0.2,2,20和200 mg/L Lj20萃取物对灰葡萄孢菌、拟盘多孢菌、弯孢霉和茄链格孢菌菌丝生长及孢子产生、萌发的影响,并测定200 mg/L Lj20萃取物对灰葡萄孢菌菌丝细胞膜的影响。【结果】用100 mg/L Lj20萃取物处理灰葡萄孢菌后菌丝量减少,菌丝体皱缩、断裂、原生质外渗,菌体细胞表面有许多瘤状畸形;Lj20萃取物对4种病原真菌的菌丝生长、孢子产生和萌发均有明显抑制作用,其中对灰葡萄孢菌的抑制作用最强,抑制菌丝生长的EC50为0.96 mg/L,抑制孢子萌发的EC50为8.33 mg/L,200 mg/L Lj20萃取物对其孢子产生的抑制率为89.4%;用200 mg/L Lj20萃取物处理后的灰葡萄孢菌培养液在260 nm处均出现1个吸收峰,而对照(10 g/L NaCl处理)无吸收峰出现。【结论】Lj20萃取物对4种供试病原菌的菌丝形态和生长、孢子产生和萌发均有抑制作用,对细胞膜透性也有明显影响。

[Objective] The study was to realize antifungal mechanism of endophytic actinomyces Lj20 extracts. [Method] The effect of Lj20 extracts （100 mg/L） on mycelia of Botrytis cinerea Pers. was observed. The effects of Lj20 extracts which concentration contained 0.02,0.2,2, 20 and 200 mg/L on mycelia growth, spore formation and germination of Botrytis cinerea Pers. ,Pestalotiopsis spp. ,Curvularia spp and Alternaria solani （Ell. et Mart） Jones et Grout. were measured,and the influence of Lj20 extracts on cell membrane of Botrytis cinerea Pers. was determined. [Result] After treated with Lj20 extracts （100 mg/L）, the mycelia were reduced, crenate and broken. The tuberculate malformation appeared, and the protoplast exosmosed. There was obvious inhibition effect of Lj20 extracts against mycelia growth, spore formation and spore germination of four pathogens,the effect of which was most obvious against Botrytis cinerea Pers. EC50 of inhibiting mycelia growth was 0. 96 mg/L, and EC50 of spore germination was 8. 33 mg/L. Inhibition rate of 200 mg/L Lj20 extracts against spore formation was 89. 4% Botrytis cinerea Pers. culture fluid treated with 200 mg/L Lj20 extracts had absorption maxima at 260 nm,but the control didn＇t have. [Conclusion] Lj20 extracts had inhibition on mycelia morphology and growth, spore formation and germination of four pathogens and had obvious effects on cell membrane permeability.