干旱胁迫与菜心叶片活性氧代谢的研究

STUDY ON THE RELATIONSHIP BETWEEN DROUGHT STRESS AND ACTIVATED OXYGEN METABOLISM OF FLOWERING CHINESE CABBAGE (Brassica campestris L.ssp.chinensis var. utilis)LEAVES

干旱胁迫导致菜心叶片清除活性氧的平衡体系受到破坏，叶片ＳＯＤ活性和ＡＳＡ含量逐渐下降．轻度胁迫引起叶片ＣＡＴ活性上升，而高度胁迫ＣＡＴ活性下降．随着干旱胁迫时间的延长，叶片的ＡＰ、ＰＯＤ活性逐渐上升，ＭＤＡ含量不断增加，自动氧化速率逐步提高，特别是在干旱胁迫的第６ｄ开始，膜脂过氧化加剧，明显地抑制了菜心植株的生长发育．

ffects of drought stress on plant growth, activities of AP, SOD, CAT and POD,ASA content, MDA level and autoxidation rate in flowering Chinese cabbage leaves were studied. The results showed that with the time and intensity of drought stress , activities of AP and POD , MDA content and autoxidation rate increased gradually , while activity of SOD and ASA content decreased gradually . Activity of CAT under lighter drought stress increased sharply , but under higher drought stress above 4 days it decreased rapidly.When the drought stress was removed and restored to supply water 2 days,activities of AP, POD and CAT , ASA content , MDA level and autoxidation rate decreased gradually , but activity of SOD increased rapidly . The data suggested that the equilibrium systems of activated oxygen eliminated were destroyed in flowering Chinese cabbage leaves because of drought stress,and membrane lipid peroxidation was enhanced and the growth and development of plant was inhibited markedly.