冻害胁迫对小麦叶片抗寒生理生化指标的影响

研究了大田冬季冻害条件下,幼穗发育不同阶段的小麦叶片内可溶性蛋白质、可溶性糖、脯氨酸(Pro)、抗坏血酸(ASA)和谷胱甘肽(GSH)等抗寒物质含量的变化。结果表明,冻害胁迫期间,植株幼穗发育进程快(播期较早)、且受冻害较重的豫麦34号和郑麦9023叶片中可溶性糖、可溶性蛋白质和抗坏血酸含量均显著低于幼穗发育进程慢(播期较晚)、受冻害较轻的品种豫农949和偃展4110,表明其适宜作为胁迫过程中小麦抗冻性的鉴定指标。冻害胁迫期间,4个小麦品种不同幼穗发育植株的叶片内脯氨酸和谷胱甘肽含量均比寒流来临之前增幅大,幼穗发育进程快且受冻害较重的豫麦34号和郑麦9023品种,这2种物质含量显著高于幼穗发育进程慢、受冻较轻的豫农949和偃展4110,推测这2种物质不宜作为小麦抗冻性的鉴定指标。

Effects of Freezing Stress on Anti-chilling Contents in Wheat Leaves

The contents of soluble sugar,soluble proteins,proline(Pro),ascorbate(ASA) and glutathione(GSH) in leaves were measured and compared among four wheat cultivars with different deve-lopment status under field freezing stress conditions.The results indicated that the spike development speed was reversely correlated with the freezing tolerance of wheat plants.During the field freezing stress period,the soluble sugar,soluble proteins and ASA contents were higher in leaves of wheat cultivars Yunong 949 and Yanzhan 4110,which were at later spike development status and suffered lower freezing injury,suggesting they should take part in the freezing tolerance,and be suitable for the indexes to identify the freezing tolerance of wheat.During the freezing stress period,however,the contents of GSH and Pro in leaves increased quickly in leaves of wheat cultivars Yumai 34 and Zhengmai 9023,which were at earlier spike development status and suffered severe freezing injury,indicating that GSH and Pro could not be positively correlated with freezing tolerance,and not be suitable for the indexes to identify the freezing tolerance of wheat.