低酚棉抗枯萎病生化机制初探

A Preleminary Study on the Biochemical Mechanism of Glandless Cotton Resistance to Fusarium wilt

在人工接种枯萎菌后，低酚棉植株体内的次生代谢─—莽草酸途径中的关键酶ＰＡＬ的活性、多酚的含量以及ＰＰＯ的活性都有不同程度的升高。但抗病品种比感病品种上升的更早更多。ＰＡＬ活性的增强与多酚含量的提高以及ＰＰＯ活性的上升基本上是同步的。这说明多酚含量的增加与莽草酸代谢途径有关，而ＰＰＯ活性与多酚含量同步提高可使合成的多酚被氧化成醌，这更增强了对病菌的毒性。

The dynamics of interaction of glandless cotton and Fusarium oxysporum f.sp.vas-infectum was studied.After inoculation the activity of PAL and PPO,the content of phenoliccompounds in both resistant and susceptible glandless cotton cultivars incresaed in various de-gree.But in resistant cultivars,the increase was earlier and greater.The increase of PAL ac-tivity,phenolic compounds content and PPO activity were basically synchronous.This sug-gested that the phenolic compounds produced by cotton plants after inoculation was related toPAL.The increase of PPO activity in early stage after inoculation made the phenolic com-pounds be oxidated into quinone which was more toxic to fungus.