冬小麦和春小麦的大规模杂交近年来已开始进行。1970年以前,冬、春小麦的杂交授粉一般都是在实验窒和温室进行的,这可以控制温度,使冬、春小麦同时开花。几个优良的小麦品种一如美国的“撒切尔”品种(Thatcher),就是用这种方法培育的。七十年代初,国际玉米和小麦品种改良中心在墨西哥高原找到一处可以在大田进行冬、春小麦杂交的地方。在这里,冬小麦于11月播种,出苗后的低温,可以使冬小麦完成春化。春小麦于翌年1月播种在同一地块,达时温度已经回升,春小麦已无冻害之虞。 Large-scale crosses between winter wheat and spring wheat have started in recent years. Before 1970, winter and spring wheat cross pollination are generally carried out in the experimental stirs and greenhouse, which can control the temperature so that winter and spring wheat flowering at the same time. Several fine varieties of wheat, like the Thatcher in the United States, were cultivated this way. In the early seventies, the International Maize and Wheat Variety Improvement Center found a place on the Mexican Plateau where winter and spring wheat crossings can be made in the fields. Here, winter wheat is planted in November and the post-emergence low temperature can make vernalization of winter wheat. Spring wheat sown in January the following January in the same plot, when the temperature has risen, spring wheat has no risk of frost damage.