APPLICATION OF THE LEAF PHOTOSYNTHESIS MODEL FOR FORECASTING EFFECT OF DROUGHTON WINTER WHEAT IN NORTH CHINA PLAIN

The North China Plain is one of the most important food crop production regions in China, and the winter wheat is frequently influenced by droughts during its growth periods. In order to give the accurate drought information, a water stress experiment was made during the jointing stage of winter wheat in the Shandong Agricultural University. The photosynthesis change due to water stress was measured systematically, and a number of agrometeorological indexes responding to the water stress were determined. A combined model is established for simulating leaf photosynthesis based on the data observed with Licor-6400, which includes environmental factors such as CO2 concentration, solar radiation, temperature and soil humidity. Validation of the model shows that it can simulate photosynthetic rate fairly well, and the coefficient of correlation can reach 0.98 with 99 samples. A great deal of observed data is given, which provides basic parameters for establishing the agrometeorological model so to forecast the effect of drought on winter in North China Plain.