春季冬小麦冻害气候及生理生化原因分析

目的]分析气候变暖背景下春季冬小麦冻害多发的气候和生理生化原因。方法]以2007年春季北方冬麦区相继发生的2次大范围严重冻害为例,应用河南省具有代表性的3个国家气象观测站和农业气象观测站资料,结合河南省农业厅统计资料和广大气象、农业科技工作者的田间调查资料,系统分析冻害发生前的气候条件、发生时的灾害天气过程、冬小麦不同生育期生理生化过程与气候适应性。结果]从冬小麦播种至冻害发生期间温度持续偏高,冬小麦生育期提前,生长发育和生理生化过程加快,植株抗寒能力降低,是造成冬小麦大面积冻害的基本原因;2次强降温天气过程气温下降幅度大、持续时间长是造成冬小麦冻害的直接气候因子;农业生产技术变化等因素对冬小麦冻害起到一定作用。结论]气候变暖背景下,冻害等自然灾害多发,生产上应选用产量、品质、抗逆性综合性状优良的冬小麦品种,并适当调种播期,减少灾害损失。

Research on the Freeze-injury Climatic Condition for Winter Wheat in Spring Season and Analysis of Its Physiological and Biochemical

Objective]The climatic condition resulting in the frequency occurrence of freezing damage of winter wheat in spring under global warming and its physiological and biochemical reason were analyzed.Method]Two heavy freezing disaster at large scale of winter wheat in north part of China in 2007 was taken as the example to systematically analyze the climatic condition before the disaster-occurring,the procedure during the disaster-occurring,the physiological and biochemical index in different growth stages and the adaptability of winter wheat based on the data from 3 State/Henan provincial weather observation stations and combined with the investigation data in field.Result]The results showed the faster winter wheat growth could cause its early growing period and rapid physiological and biochemical development because the temperature from its sowing to freezing-occurring had been relevantly high so that the resistance of the wheat plant to cold damage was reduced,which was basic reason of freezing disaster.The twice weather process of sharply temperature reduction,which lasted for long time directly led the freeze injury of winter wheat.The variation of other factors such as agricultural technique was one of the reasons resulting in disaster.Conclusion]In the context of climate warming,cold injury and other natural disasters occurred frequently,therefore,those wheat varieties with high yield,high quality and strong resistance should be selected,and their sowing periods should be appropriately adjusted,so as to reduce the loss caused by the disasters.