１９９８年的暖冬使夏熟作物生育进程严重超前，小麦拔节孕穗提前近１个月。１９９９年２月１９日的寒潮气温仅－１～２℃，对小麦影响大。麦苗主茎及大分蘖严重冻害，幼穗冻死率高达 ４４． １％。 ３月上中旬剑叶相继抽出，出现了极为罕见的剑叶扭曲抱穗，以及穗轴节上着生重 The warm winter in 1998 brought the crop maturity of summer crops ahead of schedule. The wheat booting section booting nearly one month earlier. February 19, 1999 cold temperature of only -1 ~ 2 ℃, the impact of wheat. Wheat stalks and large tiller severe frost damage, fry mortality of up to 44. 1%. In March on the middle of the flag were extracted from the leaves, there is a very rare sword leaf distorted spike,