Application of DSSAT model for sowing date management of C4 summer cereals for fodder and grain crops under irrigated arid environment

Fodder and grain yield of maize,millet and sorghum is constrained by environ-mental conditions by early or delay sowing dates instead optimum sowing dates. for optimization of fodder and grain yield,sowing at the suitable time to fit the cultivar physiological maturity duration and crop growing season is very important. crop growth models could be used to find out the appropriate sowing time for a region. the purpose of this study was to evaluation and application of csm-ceres models of maize,millet and sorghum for its capability to simulate growth,development,fodder and grain yield at various sowing dates. three sowing dates treatments were applied for each crop experiment for grain purpose maize (sd1=10 july,sd2=17 july and sd3=2 august) millet (sd1=20 july,sd2=4 august and sd3=10 august) and sorghum (sd1=15 august,sd2=23 august and sd3=27 august) in year 2015. same sowing dates were applied as a treatment for fodder purpose for each crop experiment. evaluation with the experimental data showed that performance of the csm-ceres models of maize,millet and sorghum were well as indicated by good accurate simulation of crop phenology,total dry matter accumulation and fodder and grain yield against field trials observed data. for fodder production,d-value for maize,millet and sorghum was 0.98,0.99 and 0.90; respectively. while,0.98,0.99 and 0.96 was the d-value for maize,millet and sorghum crops,respectively for grain yield. the rmse value was 547.92,272.11 and 299.73 for maize,millet and sorghum,respectively for fodder yield. 194.17,122.62 and 143.64 was rmse value for maize,millet and sorghum,respectively for grain yield. the simulation scenario showed that,mean maximum fodder and grain yield (at 50th percentile) were recorded for maize crop sown on 10 july,millet on 20 july and 4 august,respectively and sorghum on 23 august. therefore,dssat model could be applied effectively as a decision making tool for sowing date management of c4 summer cereals to accomplish local demand of grain and fodder for human beings and animals,keeping in view,the climate change situations under irrigated arid environment.