自然降温过程中南方红豆杉叶片水分、渗透调节物质的动态变化与低温半致死温度的关系

The relationship between changes of water content and osmoregulation substances and semilethal low temperature in T. chinensis var.mairei as temperature falls

研究了南方红豆杉叶片低温半致死温度与水分和渗透调节物质随气温下降的变化．结果表明，低温半致死温度降低的同时，叶片饱和含水量、自由水和淀粉含量下降，束缚水、可溶性糖、可溶性蛋白和游离脯氨酸含量增加．这些物质的适应性变化导致低温半致死温度的下降是抗寒性提高的生理基础．

The semilethal low temperature of T. chinensis var.mairei leaves and the changes of water content and osmoregulation substances have been studied. The results show that relative water content and the content of free water and starch of T. chinensis var.mairei leaves decrease while the content of bund water, soluble suger, soluble protein and proline increase with the falling of the semilethal low temperature. The adaptive changes of these substances leading to the falling of the semilethal low temperature is the physical foundation of improvement of the cold resistance.