橡胶树白粉菌诱导寄主及非寄主植物产生活性氧积累的研究

Study on the accumulation of active oxygen in host and non-host plants during the infection of Oidium heveae

采用DAB染色法观察了橡胶树、马占相思、芒果树和假败酱等植物叶片在接种橡胶树白粉菌后不同时间点的活性氧的积累和白粉病菌的侵入情况。结果表明,橡胶树叶片在接菌后24 h才能检测到微弱活性氧的积累,接菌后48 h活性氧的积累量略有增强,接菌后72 h达到最大强度,之后减弱,接菌后120 h白粉病菌产生分生孢子并且成功侵入叶片组织。马占相思叶片接菌后白粉菌与植物叶片互作的整个过程中活性氧变化规律与橡胶树观察结果相同,接菌后24 h出现活性氧积累,此后随时间的变化活性氧积累先增强后减弱,120 h白粉菌可以产生分生孢子并顺利侵入叶片组织。芒果树叶片接菌后12 h即可检测到大量的活性氧产生,整个互作过程中,活性氧积累量大,接菌后120 h时白粉菌虽然可以产生分生孢子,但未能导致芒果叶片发病。假败酱叶片接种白粉菌后,接菌后12 h可观察到强烈的活性氧积累,随时间的变化染色程度不断加深,染色斑范围扩大,接菌后72 h观察到白粉菌无法继续扩展,最终无法成功侵入叶片组织。观察结果揭示了活性氧,尤其是浸染早期活性氧的积累在植物抵抗白粉病侵染中发挥的重要作用。

DAB reaction was used to examine the active oxygen accumulation in Oidium heveae with host and non-host plants interaction, Mangifera indica, Acacia mangium, Stachytarpheta jamaicensis and Hevea brasiliensis were used in this study. The results showed that in the host interaction between O.heveae and Hevea brasiliensis, active oxygen was detectable after 24 h interaction, the epidermal cells produced relatively more active oxygen in the first 48 h. After 72 h interaction the radio of active oxygen reached the highest and then became weak, it could produce eonidiophores and induce rubber tree disease after 120 h interaction. When O.heveae was inoculated with Acacia martgium, there was the same active oxygen accumulated as rubber trees. In the non-host interaction between O. he~,eae and Mangifera indica, much more active oxygen was accumulated in 12 h, but the reaction what the plant cell did could not resis the pathogen. When Stachytarpheta jamaicensis interacted with O.heveae, much more active oxygen was examined, and it could restrain the pathogen continue to expand effectively. These results suggested that active oxygen was one of the symbols of plant defense response in plant against O.heveae.