摘要
以0,5%,15%,25%聚乙二醇(PEG-6000)对白沙蒿进行水分胁迫处理,研究其对胁迫的生理响应。结果表明,随着胁迫程度的加强,白沙蒿叶片相对含水量明显降低,叶片膜脂脂肪酸各组分含量发生明显变化,水分胁迫白沙蒿幼苗导致叶片膜脂脂肪酸的合成趋向饱和化。5%,15%PEG胁迫下膜脂趋向饱和化有利于减少不饱和脂肪酸的过氧化作用,减弱因膜脂过氧化所引起的对细胞膜系统的伤害;25%PEG处理下的膜脂过饱和化导致膜功能损伤。棕榈油酸、亚油酸在白沙蒿抵御水分胁迫过程中发挥维持一定膜脂不饱和度的重要作用。白沙蒿体内重要的渗透调节物质脯氨酸和可溶性糖含量在水分胁迫过程中虽然明显增加,但不能阻止膜脂过氧化作用对细胞的伤害。
Physiological responses of Artemisia sphaerocephala to water stress were studied by treatment of 50%, 15% and 25% polyethylene glycol （PEG-6000）. Results showed that, relative water content of leaves sig- nificantly reduced with the increasing concentration of PEG, the fatty acid compositions of leaves dramatically changed, PEG stress leads fatty acid of A. sphaerocephala leaves saturated. Under 5% and 15% PEG treat- ments, leaves lipid tend to saturated, which reducing the chance of peroxidation of unsaturated fatty acid and preventing damage of cell membranes; under 25 % PEG treatment, lipid saturation led to membrane function impairment. Palmitoleic acid and Linoleic acid play important roles in maintaining certain membrane lipid un- saturation in A. sphaerocephala under water stress. The contents of two important osmotic adjustment sub- stances, proline and water soluble sugar, increased significantly under water stress, however, this could not prevent the damage of cell membrane induced by fatty acid peroxidation.
出处
《草业学报》
CSCD
北大核心
2015年第2期55-61,共7页
Acta Prataculturae Sinica
基金
国家重点基础研究发展计划(973计划)(2014CB138703)
高等学校博士学科点专项科研基金(20120211110029)
长江学者和创新团队发展计划(IRT13019)资助
关键词
白沙蒿
PEG-6000
水分胁迫
生理特性
脂肪酸
Artemisia sphaerocephala
PEG-6000
water stress
physiological characteristics
fatty acid
