盐胁迫对大白菜幼苗生理生化特性的影响

为了探讨大白菜耐盐机理、筛选耐盐性鉴定指标，建立苗期耐盐性鉴定方法，选用了６个具有不同耐盐性的大白菜材料，用Hoagland营养液水培方法，研究了不同浓度NaCl胁迫处理下大白菜盐害指数、脯氨酸含量、可溶性糖含量、游离氨基酸含量和丙二醛（MDA）含量的变化规律。结果发现，随着NaCl处理浓度的增加以及胁迫时间的延长，大白菜幼苗叶片中的MDA含量、脯氨酸含量、可溶性糖含量以及游离氨基酸含量均呈上升趋势。不同大白菜品种的盐害指数表现出不同程度的增加。盐害指数和MDA含量在不同品种间表现了明显差异，能较好地反映大白菜各品种苗期的耐盐性，可作为大白菜耐盐性的筛选指标。

Effects of NaCl Stress on Physiological and Biochemical Characteristics in Chinese cabbage Seedling

To study the salt-tolerant mechanism , select the salt-tolerant indicators and find a method for judging salt-tolerance of Chinese cabbage at seeding stage, Six cultivars with different salt tolerance were used in this study, and Hoagland solution culture method was applied to investigate the dynamic of several physical and biochemical indexes, such as the content of proline, soluble sugars, free Amino acid and MDA in the leaves of Chinese cabbage, under different NaCl-stress pressure. The results showed that, with the increase of salt concentration and the prolonging time of NaCl stress, the contents of proline, soluble sugar,free Amino acid and MDA increased gradually and the salt injury index increased differently among cultivars. The salt injury index and MDA content were distinguishable in various cultivars and could be used to select salt tolerant germplasm in Chinese cabbage at seeding stage.