苍耳提取物对番茄灰霉病菌的抑制作用及抑菌机理初探

Primary study on fungistasis and fungistatic mechanisms of Xanthium sibiricum on Botrytis cinerea

以番茄灰霉病菌为供试材料研究了苍耳丙酮提取物对番茄灰霉病菌菌丝生长、孢子形成、孢子萌发的抑制作用及对灰霉病菌菌丝形态、细胞膜透性、可溶性蛋白质含量和菌体过氧化氢酶活性的影响。结果表明,苍耳提取物对番茄灰霉病菌具有较强的抑制作用,当苍耳提取物浓度为20 mg/mL时,其对菌丝生长的抑制率可达到70%以上,EC50为11.74 mg/mL;经浓度为30 mg/mL的提取物处理的灰霉菌产生的孢子数仅为33 500个,与对照的孢子数225 000相比,抑制率高达85.1%,对孢子萌发的抑制率达77.4%,对孢子的形成和孢子萌发表现出极强的抑制作用。苍耳提取物能引起菌丝细胞膜透性发生变化,造成液体培养基电导率增加;灰霉菌菌丝体可溶性蛋白质含量和过氧化氢酶活性下降;阻碍灰霉菌菌丝的生长,经苍耳提取物处理的菌丝变细、分枝增多、节间拉长;分生孢子少且呈畸形,孢子芽管短小。

The mode of action of an acetone extract from Xanthium sibiricum on Botrytis cinerea, including the inhibition effect on hyphae, spore formation and germination of B. cinerea spores were studied. We also tested penetrability of cell membranes and change of soluble protein content and CAT following treatment with the extraction of X. sibiricum, and the shape of hyphae was observed. The extract from X. sibiricum had high antifungal activity to B. cinerea. When the concentration was 20 mg/mL, the inhibition rate was over 70%. The EC50 was 11.74 mg/mL. Following treatment with 30 mg/mL of extract from X. sibiricum, quantity of conidiophores of B. cinerea were 33 500. Compared with the CK of 225 000, the inhibition rate was 85.1% and that of spore germination reached 77.4 %. The X. sibiricum extraction had a strong inhibition effect on the formation and germination of spores of B. cinerea. It resulted in leakage from mycelium and change of cell membrane permeability to increased conductivity. Soluble protein content and CAT from B. cinerea also declined. The extracts caused conidial germ tubes to become shorter and weaker and hyphae were not generally uniform in shape, had more branching and a longer space between burls. Conidiophores were malformed.