Study On Growth Simulation Model Of Indica And Japonica Rice And Its Application

This study takes Huanghuazhan,Yangliangou6,Nanjing 9108,Yongyou 4949 as test materials,measurement data of dry matter,leaf angle,photosynthetic rate and other indicators in Wuxue and Zaoyang as the basis,reference to domestic and foreign mature model,constructed the indica and japonica type rice growth period,photosynthesis and the dry matter accumulation,dry matter distribution and yield index model.Coupling and window operation between the models by using SQL server and C#,set up Indica and Japonica rice growth model both the mechanism and utility.The specific contents and conclusions are as follows:(1)This model based on the theory of physiological growth time constant.Used temperature sensitivity(TS)and photoperiod sensitivity(PS),IE,FPF as model parameters to quantify genetic differences among the varieties.The genetic parameters after optimization can effectively reflect the difference in physiological characteristics of the varieties,which is in line with the actual results.For example,simulated heading and maturity prediction errors are not more than 2 physiological day of Huanghuazhan in Wuxue,the maximum error is the first sowing simulated heading and maturity stages as 1.68 and 1.60,the total RMSE were 1.22 and 1.03.(2)Used specific leaf weight to calculate of rice leaf area,through field measurement data to establish a mathematical model of rice leaf weight with physiological development time change is simple,and easy to determine the model parameters,thus improving the usability and accuracy of the model.The model has a good fitting degree and a high accuracy.From the simulation results,the green specific leaf weight of rice population changes faster in the early stage of growth and development,and the later stage shows a trend of slow growth.(3)Used the Gauss hierarchy of mature to construct rice canopy photosynthetic active radiation model.Through the analysis of leaf angle of different rice varieties construction of distribution function,to calculated the direct radiation extinction coefficient of different varieties rice canopy.Simulated diurnal change of air temperature to describe the effects of temperature on photosynthesis more accurate and reasonable.The genetic parameters of hybrid rice and conventional rice are 25.574 and 18.777 ?molCO2·m-2·s-1.(4)Introduce dry matter allocation index to quantify the distribution of dry matter in organs of rice at different growth stages.This paper through the piecewise function to simulate the rice root dry matter allocation index changes with the growth and development,through the single peak curve and S curve to simulate the rice green leaf dry matter allocation index,The R2 of four varieties' root,leaf and panicle function models were 0.917,0.937,0.965,0.997,0.929,0.906,0.940 0.956,0.890,0.998,0.969,0.930.The dry matter of each organ were compared between the actual value and simulation value,the simulation results show that the overall performance is better.The total RRMSE of varieties' measured yield and simulation yield in different sowing is 11.4% in Wuxue in 2015,the model simulation results is ideal.(5)The analysis of simulation yield of four varieties rice showed that: the simulated yield with little difference between the indica and japonica on the whole.Yongyou4949 simulated yield slightly higher than Yangliangyou6,Nangeng9108 slightly lower than Huanghuazhan.Because the purchase price Japonica japonica rice is higher,it has better economic benefit,planting Yongyou4949 can increase 4847.09 yuan/ha then Yangliangyou6,planting Nanjing 9108 can increase 3297.38 yuan / ha than Huang Huazhan.Through the comparison of the simulation yield in different years and the temperature of Jul and Aug can found that: simulated yield decreased obviously in high temperature year(2013)which Wuxue cut the most serious;and the yield reductions of different varieties were different.Yangliangyou 6 reduced the most,Nangeng 9108 is minimum.Wuxue as the representative of the Southeastern Hubei has rich light and temperature resource,high temperature damage probability and degree is higher.if planting mid-rice,not only light temperature resources are not fully utilized,but also the yield can not be guaranteed;Zaoyang,Suizhou,Wuhan,Jingmen and Jingzhou where high temperature damage probability and intensity is low,mid-rice yield is significantly increased.Through the comparison of simulated yield of different sowing date can found that: Yangliangyou6,Huanghuazhan and Yongyou 4949 which the temperature sensitivity is strong.These varieties which flowering period during the period of high temperature simulated yield had reduced in different degree.The appropriate sowing date postponed can avoid high temperature that Huanghuazhan and Yangliangyou6 simulation yield can significantly increased,but the Yongyou4949 simulated yield did not increase significantly.Nanjing 9108 which temperature sensitivity is relatively low,has strong ability to resist high temperature,so high temperature did not significantly reduce simulated yield.But as the sowing date postponed,the growth period is greatly shortened,its simulated yield decreased significantly,so the sowing date should not be too late.