不同冬小麦品种拔节期抗冻性差异及相关基因表达分析

Difference Analysis of Frost Resistance of Different Winter Wheat Varieties at Jointing Stage

为探究不同品种冬小麦拔节期抗冻性差异,以冬小麦品种郑麦366和百农207为材料,在人工气候室-5℃低温胁迫连续处理24 h后,测定叶片丙二醛(MDA)和游离脯氨酸含量及抗逆相关SOD、POD、WCS120、P5CS和LEA基因的相对表达量,分析了低温胁迫后两个品种间各指标的变化特点。结果表明,连续低温处理24 h后,两个品种的MDA和游离脯氨酸含量均较处理前显著下降,且百农207的MDA和游离脯氨酸含量分别显著低于和高于郑麦366。百农207叶片中除SOD在24 h时与郑麦366表达量无显著差异外,其余四个基因表达量均显著高于郑麦366。在低温处理24 h时百农207这5个基因的表达量都较0 h时显著升高,而郑麦366则显著下降。低温胁迫后,郑麦366幼穗受冻率高于百农207。因此,百农207的拔节期抗冻性高于郑麦366,也说明在冬小麦生产过程中选择种植抗冻性较强的品种可以缓解拔节期低温的危害。

In order to explore the differences in frost resistance at the jointing stage of different wheat varieties,two winter wheat varieties Zhengmai 366 and Bainong 207 were used as materials.The differences in frost resistance of different wheat varieties were verified by measuring the contents of the malondialdehyde(MDA),the free proline,and the relative expression of the stress-related genes in leaf tissue under cold stress of-5℃for 24 hours.The results showed that the MDA content in Bainong 207 was lower but the free proline content was higher than those in Zhengmai 366 significantly after the wheat plants suffered from cold stress for 24 hours.The relative expression of POD,WCS120,P5CS and LEA genes were higher in Bainong 207 than those in Zhengmai 366,and the relative expression of SOD,POD,WCS120,P5CS and LEA genes were increased in Bainong 207 but those were decreased in Zhengmai 366 after cold stress for 24 hours.The damage rates of young ears in Zhengmai 366 was higher than that of Bainong 207 after wheat plants suffered from-5℃freeze-stress for 24 hours.Based on this,the overall frost resistance of Bainong 207 was higher than that of Zhengmai 366.Thus,wheat varieties with stronger frost resistance should be selected in the field cultivation process to alleviate the harm caused by low temperature stress.