低温胁迫不同类型油菜品种(系)的生理变化特征

为油菜抗寒育种提供参考,采用盆栽试验研究4℃低温胁迫不同类型油菜幼苗2h、6h、12h和24h后的生理变化特征。结果表明:随着低温胁迫时间的延长,不同类型油菜幼苗的相对电导率存在一定差异,白菜型油菜和芥菜型油菜的相对电导率随胁迫时间的延长呈先升高后降低趋势,甘蓝型油菜呈升高-降低-再升高变化趋势。不同类型油菜品种(系)的脯氨酸含量、可溶性糖含量和叶绿素a/b含量的变化趋势一致,即脯氨酸含量随低温胁迫时间延长呈先升高后降低趋势,可溶性糖含量和叶绿素a/b含量随低温胁迫时间延长呈先降低后升高趋势。不同类型油菜幼苗在早期低温胁迫下均会快速响应,即油菜的抗寒性越强其生理响应越迅速,对低温的适应性也越快,不同类型油菜品种(系)的抗寒性强弱依次为陇油7号陇油6号9393521012。

Physiological Characteristics Variation of Different Rapeseed Cultivars(lines) under Low Temperature Stress

In order to provide references for breeding of cold-resistant rapeseed cultivars, a pot experiment was conducted to explore the physiological characteristics variation of different rapeseed cultivars under low temperature stress(4℃) for 2 h, 6 h, 12 h and 24 h.Results: Relative conductivity of different rapeseed seedlings varied with the duration of low temperature stress, which first increased and then decreased for Brassica rapa and Brassica juncea, and Brassica napus showed the change trend of first increased, then decreased and increased again.Contents of proline, soluble sugar and chlorophyll a/b had the same variation trends in different rapeseed cultivars(lines).With the prolonging of low temperature stress, proline content first increased and then decreased, contents of soluble sugar and chlorophyll a/b first decreased and then increased.The rape seedlings made quick response to low temperature stress in the early stage although genotype is different.The stronger the cold resistance is, the response and the adaptability of physiology are more quickly to low temperature stress.The order of low temperature resistance of different rapeseed cultivars was Longyou 7 > Longyou 6 > 939 > 352 > 1012.