必要性近二十年来,世界小麦产量几乎每年平均以3.4%的速度增长着.然而,在多数情况下,产量的急增与半矮秆品种的推广和株高的降低是联系在一起的.据统计,半矮秆小麦占当今世界小麦的半数以上,在集约经营地区更是以半矮秆品种为主,例如在美国的太平洋西北地区分别占冬、春小麦的85%和95%,在保加利亚、南斯拉夫、法国和西欧其它一些国家栽培 Necessity World wheat production has grown at an average annual rate of 3.4% annually for nearly two decades, however in most cases the surge in production is associated with the promotion of semi-dwarf varieties and plant height reduction. According to statistics, semi-dwarf wheat accounts for more than half of the world’s wheat in the intensive management area is dominated by semi-dwarf varieties, such as the United States in the Pacific Northwest accounted for 85% and 95% of winter wheat and spring, respectively, in Bulgaria Yugoslavia, France and some other countries in Western Europe