Abstract: The eco physiological indexes of winter wheat Lu 23 were systematically measured by using the LI-6400 portable photosynthesis analyzer in Shandong Agricultural University.The parameters of several stomatal conductance models,which were selected from the Jarvis and Ball-Berry models, were fitted by using the least square method.Then the models were validated and compared.The results indicated that Ball-Berry model 2 performed the best with the highest correlation coefficient value of 0.625(P<0.01) and the lowest root mean squared error (RMSE) value of 0.158 mol〖KG-*4〗·〖KG-*4〗-2〖KG-*4〗·〖KG-*4〗s-1.Meanwhile,Jarvis model 1 performed better than Jarvis model 2 and Ball-Berry model 1 performed the worst,with the lowest correlation coefficient value of 0.369(P<0.01) and the highest root mean squared error (RMSE) value of 0.235 mol〖KG-*4〗·〖KG-*4〗m-2〖KG-*4〗·〖KG-*4〗s-1.The applicability of the four models was quite different from that in the Yangtze River delta,which meant further research on the applicability of stomatal conductance models in different regions was necessary to provide more reliable references for the future study on the SPAC.

Key words: North China plain, Winter wheat, Stomatal conductance model, Applicability