真菌Sr18代谢产物对根结线虫胁迫下黄瓜叶片保护酶的影响

The effects of Syncephalastrum racemosum Sr18 metabolites on cucumber protective enzymes under root-knot nematode stress

为探究根结线虫胁迫下丝状真菌Sr18代谢产物对黄瓜的作用机理,采用温室盆栽及人工接种试验,研究了不同浓度的Sr18代谢产物对南方根结线虫胁迫下黄瓜叶片保护酶的影响。结果表明,线虫侵染黄瓜根部以后,黄瓜叶片SOD、POD和CAT活性减弱,PPO和PAL浓度降低。施加不同浓度的Sr18代谢产物,能够使线虫胁迫下的黄瓜叶片SOD、POD和CAT活性增强,使PPO和PAL的含量增加,说明Sr18代谢产物能够提高黄瓜的保护酶活性与含量,增强黄瓜对南方根结线虫的抗性。

To understand the action mechanism of Syncephalastrum racemosum Sr18 metabolites to cucumber under the root-knot nematode Meloidogyne incognita stress, the effects of Sr18 metabolites on five protective enzymes （SOD, POD, CAT, PAL, PPO） of cucumbers with/without seedling inoculation by nematodes were investigated in greenhouses. The results showed that higher levels of SOD, POD, CAT activities and PPO, PAL contents were observed in the plants pretreated with Sr18 and inoculated with nematodes than that in non-treated control, while lower activities of SOD, POD and CAT and lower contents of PPO and PAL in leaves of cucumber were observed in the plants inoculated with nematodes than that in non-inoculated control. Sr18 metabolites induced the upregulated activity of antioxidative enzymes in cucumber leaves and enhanced the resistance level of cucumber against the root-knot nematode M. incognita.