小麦返青期间的生长中心主要是生根、长叶和分蘖。从返青到起身阶段中,小麦苗情变化很大,既是小麦增苗,增穗的关键时期,又是弱苗转化升级,旺苗防倒的重要时期,因此,田间管理的中心是促苗早发稳长,提高成穗率并为穗大打基础。开春,气温回升,日平均气温达到0℃时小麦开始返青,3℃时开始分蘖。但是乐亭县早春气温回升缓慢,返青后还有20—30天的时间气 The growth centers during wheat rejuvenation are mainly rooting, long leaves and tillers. From turning green to getting up, the wheat seedling changes greatly, which is not only a crucial period for increasing wheat seedling and increasing panicle, but also an important period for transformation and upgrading of weak seedling and prevention and control of wheat seedling. Therefore, the center of field management is promoting seedling emergence Stable hair growth, increase the rate of spike and lay the foundation for spike. Spring, the temperature picked up, the average daily temperature reached 0 ℃ wheat began to turn green, tillering began at 3 ℃. But Laoting County, early spring temperatures rise slowly, there is still 20-30 days after turning green