北京及北部晚熟冬麦区的无霜期是各冬麦区中最短的,作物种植上历来存在着热量“两茬不足、一茬有余”的现象。为了提高复种指数,过去多局限于套种,而套种不利于发展机械化。因此,培育适于机械化两茬平作早熟品种,对促进本区小麦及其他粮食作物的进一步均衡及持续增产具有重大意义。北京过去的早熟品种都属于本区特有的 The frost-free period of late winter ripe winter wheat in Beijing and the northern part is the shortest among the winter wheat growing areas. There has always been a phenomenon of “two shortages of crops and more than one harvest” of calories on crop cultivation. In order to increase the multiple cropping index, in the past more limited to intercropping, and interplanting is not conducive to the development of mechanization. Therefore, to cultivate two kinds of crops suitable for mechanization as precocious varieties is of great significance to promote the further balance and continuous increase of wheat and other food crops in this area. Beijing past early varieties are unique to this area