低温胁迫对玉米发芽及幼苗生理特性的影响

摘要

To explore the effects of low temperature stress on germination and physiological characteristics of maize seedlings,the hybrid maize varieties Tiannong 9 and Tianhe 1 were used as experimental materials,and the methods of low temperature culture (6 ℃ at germination stage and 4 ℃ at seedling stage) were used in this experiment.Then the effects of agronomic characters (plant height,root length,fresh and dry weight) and physiological indexes (SPAD,Pn,MDA content,POD activity,SOD activity,proline content and soluble protein content) of maize seedling and germination (germination rate) were studied under low temperature stress.The results showed that low temperature stress significantly inhibited the germination of maize seeds and seedling growth,which decreased the plant height,root length,fresh and dry weight,Chlorophyll content and Pn.And increased MDA content,POD activity,SOD activity,proline content and soluble protein content.Howerver,there were significant differences among varieties,Tianhe 1 was more sensitive to low temperature stress.The research provided a theoretical basis for solving the problem of cold damage in maize production.%为探究低温胁迫对玉米发芽及幼苗生理特性影响,文章以杂交玉米品种天农9和天合1为试验材料,采用低温培养(发芽期6℃,苗期4℃)方法,分析低温胁迫下玉米发芽(发芽率)、幼苗农艺性状(株高、根长、地上部及地下部干鲜重)和生理生化指标(SPAD值、Pn、MDA含量、POD活性、SOD活性、脯氨酸含量和可溶性蛋白含量)变化.结果表明,低温胁迫抑制玉米种子发芽和幼苗生长,降低幼苗株高、根长、地上部地下部干鲜重、叶绿素含量和净光合速率提高MDA含量、POD活性、SOD活性、脯氨酸含量和可溶性蛋白含量.不同品种间差异显著,天合1对低温胁迫更敏感.研究成果为解决玉米生产冷害问题提供理论依据.