Abstract: It is shown from the measurement of growth rate and leaf area of wheat and the observation of microclimate in wheat field that there is a close relationship between growth rate and leaf area. In highly productive field, the leave area of wheat is maximum during the period from flowering-to milking stage, After elongating stage, the tolal amount of heat consumption from evaporation in field is larger than that of net radiation

Key words: Short photoperiod-low temperature induced male sterile rice, Photoperiod, Temperature, Fertility alteration