茄子嫁接苗根系对低温环境胁迫的响应

以‘济农2000’为对照，研究了低温胁迫下不同抗冷性茄子砧木嫁接苗根系的生理生化变化及其与抗冷性的关系.结果表明，在10 ℃(昼)/3 ℃(夜)低温处理初期，根系对低温最敏感，表现为MDA含量、冷害指数、POD活性、脯氨酸含量、可溶性蛋白含量等迅速增加，而根系呼吸速率、SOD、CAT活性等迅速降低.随着低温胁迫时间的延长，根系呼吸速率持续降低，而冷害指数持续升高，渗透调节物质基本呈增加的趋势.常温恢复3 d后，呼吸速率、渗透调节物质、SOD活性等升高,但均以抗冷性较强的赤茄砧木嫁接苗恢复能力较强，而抗冷性较弱的台茄砧木嫁接苗与自根苗较差.利用抗冷性较强的砧木进行嫁接，可显著增强茄子根系的活性，进而提高其抗冷性.

Responses of grafted eggplant seedling roots to low temperature stress

The study on the changes of physiological and biochemical properties of grafted eggplant seedling roots under low temperature stress and the relationships between these changes and cold tolerance showed that at the initial stage of treating with 10 degrees C (daytime) /3 degrees C (night), eggplant seedling roots were most impressible to low temperature, with the MDA content, chilling injury index, POD activity, proline content and soluble protein content increased significantly, and root respiration rate, SOD activity and CAT activity decreased rapidly. With the extending of low temperature stress, root respiration rate and osmotic adjustment reduced continually, while chilling injury index increased. After 3 days recovery, the respiration rate, osmotic adjustment and SOD activity were increased. Among the test materials, T2 (with Hiranasu as rootstock) had the best recovery capability, followed by T1 (with Taibyo as rootstock) and CK (Jinong 2000). Grafting with stronger cold tolerance rootstock could improve eggplant root activity, and thus, its cold resistance markedly.