拟康宁木霉 SMF2 防治大白菜软腐病机理研究

 以大白菜（Brassica campestris L. ssp. pekinensis）‘丰抗70’为试材,研究了拟康宁木霉SMF2 对大白菜软腐病的诱抗效果;并通过研究拟康宁木霉SMF2 对接种和未接种主要致病菌--欧氏杆菌胡萝卜软腐亚种（Erwinia carotovora ssp. carotovora）的大白菜幼苗生长、内源激素含量及保护酶活性的影响,探讨了木霉防治大白菜软腐病的机制。结果表明：施用拟康宁木霉SMF2（孢子≥ 0.1 g · kg^-1）显著降低大白菜叶柄软腐病病斑长度。无论大白菜幼苗是否接种软腐病菌,施用拟康宁木霉SMF2 显著提高大白菜地上部和根系鲜质量、根冠比值,提高叶片玉米素核苷（ZR）、吲哚乙酸（IAA）、脱落酸（ABA）含量,以及多酚氧化酶（PPO）和过氧化物酶（POD）活性。说明拟康宁木霉SMF2 可能主要通过促生作用和诱导抗性防治大白菜软腐病。

Research on Mechanism of Trichoderma pseudokoningii SMF2 Controlling Soft Rot of Chinese Cabbage

The induced resistance effects of Trichoderma pseudokoningii SMF2 on soft rot of the Chinese cabbage’Fengkang 70’were studied by measuring the lesion length,and the control mechanism of T.pseudokoningii SMF2 was deduced from its effects on growth,endogenous hormone contents and protective enzyme activities of Chinese cabbage seedlings inoculated with the main pathogens,Erwinia carotovora ssp.carotovora or not.The results showed that the lesion length of soft rot in petiole of Chinese cabbage were decreased significantly when treated with T.pseudokoningii SMF2(spore ≥ 0.1 g.kg-1).The fresh weight of shoot and root,ratio of root to shoot of seedlings,zeatin riboside(ZR),indole acetic acid(IAA)and abscisic acid(ABA)contents,polyphenol oxidase(PPO)and peroxidase(POD)activities in leaves of Chinese cabbage seedlings treated by T.pseudokoningii SMF2 were increased significantly,whether they were inoculated with Erwinia carotovora ssp.carotovora or not.Based on these results,it suggested that growth-promoting and induced resistance were probably the main reasons for T.pseudokoningii SMF2 controlling soft rot of Chinese cabbage.