For the sake of understanding comprehensively the propert of day-length reaction for the commum species of wheat (Triticum aestivu L.), experimental data of wheat ecology were collccled from field experiment arranged in different sowing stages in Beijing and Gui ang during 1982 -1985. The 31 varieties studied are in different ccot pcs. Growth and development process from rowing to heading of 8 varieties is reported in this article, indicating that the process from sowing to physio-elongating could be comple...