一、引论频繁的春季低温是法国北部玉米生长的碍障之一。一些遗传学家已开始注意到,起源不同的杂交种对低温的反应不同。许多研究工作都证明:苗期根际温度对玉米生长发育和植株不同器官的代谢活动影响较大;据际温度的降低或迟或早会改变叶的水分收支平衡,根系构造, I. Introduction The frequent low temperatures in the spring are one of the impediments to the growth of maize in Northern France. Some geneticists have begun to notice that different origins have different responses to low temperatures. Many researches have proved that the rhizosphere temperature at seedling stage has a great influence on the growth and development of maize and the metabolic activities of different organs of plants. According to the lower or lower temperature, the water balance of leaves will be changed sooner or later.