秋茄幼苗对盐度-淹水双胁迫的生理适应

采用潮汐自动模拟系统，探讨盐度-淹水交互处理下，秋茄幼苗叶片生理指标（包括超氧化歧化酶（SOD）、过氧化物酶（POD）、过氧化氢酶（CAT）、丙二醛（MDA）、膜透性、游离脯氨酸、可溶性蛋白）的变化特征。结果表明，盐度-淹水胁迫显著影响秋茄幼苗叶片的生理适应特征（p<0.05）。SOD活性、MDA含量及游离脯氨酸含量随盐度升高呈先升后降趋势，POD及CAT活性随盐度升高而持续降低，膜透性及可溶性蛋白含量随盐度升高而升高，短时淹水环境（2～4 h）的SOD活性、游离脯氨酸含量及可溶性蛋白含量高于长时淹水环境（6～8 h）。盐度胁迫的影响效应大于淹水胁迫，水盐胁迫较单一胁迫对秋茄幼苗的伤害更为严重。

Physiological Adaptability of Kandelia candel Seedlings to Salt-water Stress

In the study, the influences of two hydrological factors(salinity and waterlogging time)on the physiological characters of Kandelia candel in the leaf were studied using the automatic tidal-simulation device in a greenhouse. The contents of physiological characters including superoxide dismutase(SOD), peroxidase(POD), catalase(CAT), MDA, membrane permeability, free proline content and soluble protein content were determined in the salinity and waterlogging treatments. The results showed that salinity-waterlogging had an significant effect on the physiological characters of K. candel in the leaf(p<0.05). The activities of SOD, MDA content and free proline content initially increased but then decreased with the increase of salinity. POD and CAT kept reducing as salinity increased. Membrane permeability and soluble protein content increased as salinity increased SOD activity, free proline content and soluble protein content in shorter waterlogging environment(inundated for about 2-4 h)were higher than that in longer environment(inundated for about 6-8 h). The influential effect of salinity was stronger than that of waterlogging. Salinity-waterlogging treatment resulted in more serious harm to K. candel seedlings than each stress along.