摘要
以自根苗为对照 ,研究了不同砧木对嫁接苗耐冷性的影响及生理机制。结果表明 ,与自根苗相比 ,嫁接苗的耐冷性明显提高。在低温胁迫下 ,嫁接苗冷害指数、电解质渗透率、丙二醛 (MDA)含量明显低于自根苗的 ;而叶绿素、脯氨酸含量、超氧化物歧化酶 (SOD)、抗坏血酸过氧化物酶 (AsA POD)、脱氢抗坏血酸还原酶 (DR)活性明显高于自根苗。不同嫁接苗由于砧木的不同其耐冷性也有较大差异。耐冷性强的嫁接苗叶片中电解质渗透率、MDA含量低于耐冷性弱的嫁接苗 ;脯氨酸含量、SOD、AsA POD、DR活性高于耐冷性弱的嫁接苗。因此 ,耐冷性与在低温下植株具有较高的抗氧化能力和细胞膜稳定性有关。单一生理指标不能完全正确评价西瓜嫁接苗的耐冷性 。
Compared with own-rooted watermelon, the influence of different rootstocks on chilling tolerance of grafted watermelon seedlings and its physiological mechanisms were studied. The results showed that grafting increased the chilling tolerance. Compared with own-rooted watermelon seedlings, the grafted watermelon seedlings had lower chilling injury index, lower electrolytic leakage (%), lower MDA content, higher chlorophyll, proline content and higher activities of superoxide dismutase, ascorbate peroxidase and dehydroascorbate reductase in leaves under low temperature stress. There was a considerable difference of chilling tolerance among different grafted watermelon seedlings due to the difference of rootstock chilling tolerance. The grafted seedlings with stronger chilling tolerance had lower electrolytic leakage (%), lower MDA content, higher proline content and higher activities of superoxide dismutase, ascorbate peroxidase, dehydroascorbate reductase in leaves than those of grafted seedlings with weaker chilling tolerance. Therefore, chilling tolerance may be related to higher antioxidative ability and membrane stability in the plants. The chilling tolerance of grafted seedlings could be properly evaluated by comprehensive physiological indexes but not a single physiological index.
出处
《中国农业科学》
CAS
CSCD
北大核心
2003年第11期1325-1329,共5页
Scientia Agricultura Sinica
基金
国家自然科学基金重点资助项目 (3 0 2 3 0 2 5 0 )
关键词
低温胁迫
西瓜
嫁接苗
生理变化
耐冷性关系
Watermelon
Low temperature stress
Grafted seedling
Chilling tolerance
