促生菌CH1对黄瓜酚类物质代谢的影响及与抗猝倒病的关系

Influences of Plant growth-promoting Rhizobacteria CH1 on Phenolic Metabolism in Cucumber and its Relation to Resistance to Cucumber Damping-off

为研究植物生长促生细菌CH1(Brevibacillus brevis)诱导黄瓜对猝倒病的抗性的作用机制,采用生理生化的方法,测定了黄瓜根部酚类物质代谢中苯丙氨酸解氨酶(PAL)、多酚氧化酶(PPO)活性动态及阿魏酸、绿原酸、木质素、总酚、类黄酮含量变化。结果表明,病原菌(Pythium aphanidermatum)感染时,经CH1处理的植株根部PAL和PPO活性都明显高于未经CH1处理的,同时,经CH1处理的植株根部阿魏酸、绿原酸、木质素、总酚和类黄酮含量都高于未经CH1处理的。说明CH1是通过提高黄瓜植株体内酚类物质代谢的酶活性来激发酚类物质的积累,从而诱导黄瓜对猝倒病产生抗性。

In order to explore the mechanism of the resistance to cucumber damping-off induced by plant growth-promoting rhizobacteria CH1, the physiological and biochemical method was employed to study the changes in activities of Phenylalanine ammonia-lyase（PAL）, Polyphenol oxidase（PPO） and contents of ferulic acid, chlorogenic acid, lignin, phenolic compound and flavonoid of phenolic metabolism in cucumber roots pretreated with plant growth-promoting rhizobacteria CH1 and infected by Pythium aphanidermatum. The results showed that the activities of PAL and PPO, the contents of ferulic acid, chlorogenic acid, lignin, phenolic compound and flavonoid in roots treated by CH1 increased higher than those of the nontreated when plants were infected by Pythium aphanidermatum. This indicated that CH1 could induce resistance of cucumber to P ythium aphanidermatum by increasing its enzymes activities of phenolic metabolism.