钾营养对接种炭疽病菜薹(菜心)细胞保护酶系统的影响

Effect of Potassium Nutrition and Inoculation with Colletotrichum higginsianum on Cell Protective Enzyme Systemin Flowering Chinese Cabbage

为探讨合理施用钾肥可以提高菜薹自身防卫能力和抗病能力的生理机制,研究通过接种炭疽病菌,测定3种不同钾营养水平下菜薹的超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性和丙二醛(MDA)的含量。结果表明:炭疽病菌对菜心的SOD、POD、CAT、MDA有明显的调节作用,SOD、POD、CAT在感病过程中表现为前期下降后期上升,而MDA表现为缓慢上升的过程。钾营养能影响炭疽病菌对菜薹细胞保护酶系统的调节作用,适宜的钾营养能增强炭疽病菌对菜薹植株SOD、CAT活性的诱导作用,但抑制了炭疽病菌对植株POD活性、MDA含量的诱导作用。总之,在菜薹感染病原菌后,适宜的钾营养通过调控植株的活性氧代谢平衡体系,可以提高植株的抗病性能。

In order to explain the physiology mechanism of appropriate potassium application on improvement of self-defensive capabilities and enhancement of disease resistance, 3 different doses of potassium nutrition were applied to flowering cabbage seedlings inoculated with anthraenose pathogen, then the activities of superoxide dismutase（SOD）, peroxidase（POD）, catalase（CAT）, and content of malondialdehyde（MDA） were detected. The results showed that the anthracnose pathogen significantly affected the activities of SOD, POD, CAT and content of MDA in flowering cabbage. The activities of SOD, POD, and CAT decreased at the early stages of disease infection and increased at the late stages, while the content of MDA was increasing slowly. The results also showed that potassium nutrition had an effect on the induction of anthracnose pathogen to the cell membrane protective enzyme system in flowering cabbage. The appropriate potassium nutrition enhanced the effect of anthracnose pathogen treatment of SOD and CAT activities and inhibited the effect on the activity of POD and MDA content. Therefore, appropriate potassium application to the seedlings inoculated by C. higginsianum could validly regulate metabolic balance system of activated oxygen species （AOS） and finally improve the disease resistance of seedlings.