摘要
以长春密刺黄瓜幼苗为材料,对经草酸处理或霜霉菌接种后黄瓜叶片的过氧化物酶(POD)、超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性及H2O2含量的变化进行了研究.结果表明:草酸处理或霜霉菌接种均可诱导黄瓜幼苗叶片H2O2含量显著增加,且草酸预处理后接种的叶片比相应对照叶片能更快地积累H2O2;草酸处理后叶片SOD和POD活性均升高,而CAT活性却受到一定程度的抑制.研究发现,H2O2参与了幼苗对霜霉病的抗性诱导;叶片H2O2含量的增加与其SOD、POD活性升高、CAT活性下降有关;通过调节黄瓜叶片H2O2的含量来调控有关黄瓜霜霉病抗性的防御基因表达是草酸诱导抗性的机制之一.
The activities of POD,SOD or CAT and H2O2 content were examined in cucumber leaves treated with oxalic acid or inoculated with Pseudoperonospora cubensis f. sp. cucurnerinurn. Results showed H2O2 content in leaves treated with oxalic acid were increased significantly, and accumulated faster than control after inoculation of Pseudoperonospora cubensis f. sp. cucurnerinum. After leaf treated with oxalic acid, the activities of SOD or POD were enhanced while CAT activities were inhibited in leaves. The results showed that H2O2 may be concerned with induced resistance against downy mildew. The increase of H2O2 content may be related to the increase of SOD or POD activities and the decrease of CAT activities. That oxalic acid induced defense gene expression through H2O2 was one of the main mechanism of induced resistance.
出处
《西北植物学报》
CAS
CSCD
北大核心
2008年第6期1160-1164,共5页
Acta Botanica Boreali-Occidentalia Sinica
基金
西北农林科技大学青年学术骨干支持计划
