中文摘要：

为了研究外源ABA及其抑制剂对低温下冬小麦生理生化指标的影响,以冬小麦东农冬麦1号为试验材料,于三叶期分别叶面喷施10μmol·L^-1ABA、5 mmol·L^-1钨酸钠和50μmol·L^-1氟啶酮,田间自然降温条件下,分别于10 d平均最低温度达到4、0、-10、-25℃时取叶片测定相关生理生化指标。结果显示,随着温度的降低,各处理组小麦叶片的可溶性糖、可溶性蛋白含量先升后降,在0℃达到峰值;脯氨酸、丙二醛（MDA）含量和超氧化物歧化酶（SOD）活性逐渐升高。经ABA处理后,小麦叶片的可溶性糖、可溶性蛋白、脯氨酸含量及SOD活性显著高于对照组,但不同温度下的变化水平有所差异;MDA含量低于对照组,在0℃时差异显著,说明外源ABA可提高冬小麦抗寒能力。两种合成抑制剂处理后,小麦叶片的可溶性糖、可溶性蛋白、脯氨酸含量和SOD活性（除0℃）均显著低于对照组,MDA含量（除4℃）显著高于对照组,说明其对小麦的效应与ABA处理相反,可降低冬小麦抗寒性。钨酸钠处理组各项指标与ABA处理相比变化差异显著,氟啶酮处理组各项指标与ABA处理相比差异极显著,说明ABA在参与冬小麦抗寒性的调控过程中起着重要作用,且氟啶酮对冬小麦抗寒能力影响更大。

英文摘要：

In order to study the changes of physiological and biochemical indices of leaves of winter wheat（Triticum aestivum） ‘Dongnongdongmai 1＇the seedlings were treated with 10 μmol·L^-1ABA or two different biosynthesis inhibitor of ABA（5 mmol·L^-1Sodium tungstate or 50 μmol·L^-1Fluridone） at low temperature in the field,the leaves were taken and their physiological and biochemical indicators were measured when the average daily minimum temperature reached 4,0,- 10,- 25 ℃. The results indicated that as the temperature decreased,the contents of soluble sugar and soluble protein in leaves of each treatment were decreased,which peaked at 0 ℃,while the proline content,malondialdehyde（ MDA） content,and superoxide dismutase（ SOD） activity increased gradually. The contents of soluble sugar,soluble protein and proline,and SOD activity in the leaves in the ABA treatment was significantly higher than that in the control,but the changes varied at different temperatures; MDA content in the ABA treatment was lower than that in the control,and the difference was significant at 0 ℃,which indicated that exogenous ABA could improve cold tolerancein winter wheat. The fact that the contents of soluble sugar,soluble protein and proline,and SOD activity（except 0 ℃） in the two inhibitor treatments were significantly lower than that in the control,while MDA content（ except 4 ℃） was significantly higher than that in the control was in contrast with the ABA treatment,suggested that the treatment reduced the cold hardiness of winter wheat. Compared with the indicators of the ABA treatment,treatment with inhibitor Sodium tungstate changed those indicators significantly,while treatment with inhibitor Fluridone changed those indicators very significantly,which showed that ABA played an important role in the regulation of the processes involved in cold resistance of winter wheat,and suggested the influence of Fluridone was stronger on cold resistance of winter wheat.