Abstract:Understanding how different sowing dates and irrigation scheduling affect wheat dry matter accumulation was very helpful to improve grain yield and resource utilization efficiency. Field experiments with six-levels sowing dates and four-levels irrigation for winter wheat over two years were conducted during 2017—2019 in North China Plain in Hebei Province, China. Based on the two-year experiment, combined with the literature data of coupling irrigation with sowing dates of Wuqiao Experimental Station from 2011 to 2017. The development index of “wheat clock” model was used to quantitatively express the development phase of winter wheat. The effects of different sowing date and irrigation treatment on the dynamic characteristics of biomass accumulation were analyzed by Logistic mathematical model and establishment of biomass prediction model of winter wheat. Furthermore, winter wheat yield prediction model was established based on the biomass prediction model. The results showed that sowing date affected biomass accumulation by affecting rapid growth period of biomass accumulation. With the delay of sowing date, the rapid growth period was shortened, which made the biomass decreased. The difference of the maximum aboveground biomass caused by different irrigation treatment was mainly determined by the maximum growth rate of biomass, and the increase of irrigation amount helped to increase the maximum growth rate. The characteristics of biomass accumulation of winter wheat were different under different sowing date and irrigation treatments. According to the biomass and yield prediction model of winter wheat based on accumulated temperature before wintering and water supply amount in the growing season, the root mean square error (RMSE) and normalized root mean square error (NRMSE) of measured and simulated above-ground biomass of winter wheat were 1980.2kg/hm2 and 15.7%, respectively, and the RMSE and NRMSE of measured and simulated yield were 839.7kg/hm2 and 10.6%, respectively. Logistic model based on development index can well simulate the biomass accumulation of winter wheat, and had a good simulation accuracy on yield under different sowing dates and irrigation conditions. Under adequate soil moisture conditions before sowing, the appropriate accumulated temperature before wintering was ranged from 200℃·d to 600℃·d, and the appropriate water supply amount in winter wheat growing season was between 200mm and 450mm. The research result can provide scientific basis for the reasonable control of sowing date and irrigation measures in North China, and provide ideas for the prediction of winter wheat yield under different sowing dates and irrigation conditions.