胡麻产量形成模拟模型研究

胡麻产量形成模型是胡麻生长模型中的重要子模型,其准确性关系到整个模型的模拟性能。本研究拟构建能较准确预测不同生产情况下胡麻的产量形成模型,为胡麻实际生产提供科学指导。模型利用2012—2013年胡麻西北主产区定西和榆中试验站不同肥料、不同播种方式、不同种植密度和不同氮磷水平的试验结果,以胡麻生理生态过程为主线,分别构建了产量构成因素法(基于品种遗传参数:单位面积蒴果数、每果粒数、粒重与水肥胁迫因子、累积光合速率)的产量形成模型和基于粒壳比法(基于粒壳比和蒴果干物质总量)的产量形成模型;利用2014—2015年试验区实测数据对模型进行较广泛验证。验证结果表明,产量构成因素法对定西地区不同肥料、不同播种方式、不同种植密度产量模拟值的RMSE平均为133.47 kg×hm~(-2),粒壳比法的RMSE平均为195.51 kg×hm~(-2);利用最小二乘法计算的决定系数R2产量构成因素法与粒壳比法分别为0.819 8和0.743 9。榆中地区12个氮磷处理水平产量构成因素法平均RMSE值为140.70 kg×hm~(-2),粒壳比法的RMSE平均为193.22 kg×hm~(-2);产量构成因素法与粒壳比法预测的产量值与观测值R2分别为0.832 9和0.805 8。结果表明,产量构成因素法对产量的模拟效果优于粒壳比法,针对不同品种不同栽培方式,把单位面积蒴果数、每果粒数与粒重作为品种遗传参数的产量构成因素法能更精确模拟胡麻的产量,具有较高的预测性和通用性。

Simulation model for yield formation of oilseed flax based on APSIM

AbstractThe oilseed flax yield formation model was developed to predict biomass yield and provide scientific guidance for oilseed flax production, which was an important sub model of oilseed flax development model, APSIM-Oilseed flax. Its’ accuracy was related to the performance of APSIM-Oilseed flax. In the study, the oilseed flax yield formation model was developed for Northwest China using data generated from experiments, and was calibrated and validated under varying fertilizers, seeding methods, planting densities, nitrogen and phosphorus application conditions. The experiments were conducted at Dingxi and Yuzhong of Gansu Province from 2012 to 2015. Calibration was done using data for 2012–2013 and validation with data for 2014–2015. Two methods, yield component factors method and grain pod ratio method, were used to build oilseed flax yield formation model. The oilseed flax yield formation model of yield component factors was based on genetic parameters, such as, number of pods per unit area, grains number per pod, grain weight and water and fertilizer stress factors. The oilseed flax yield formation model of the grain pod ratio was based on grain pod ratio and total dry matter. The results showed that the average RMSE for the model-simulated and field values related to the yield component factors method under different fertilizers, sowing densities in Dingxi was 133.47 kg per hm2. Then it was 195.51 kg per hm2 for the grain pod ratio method. ThenR2 values were 0.819 8 and 0.743 9 for the yield component factors and grain pod ratio, respectively. The average RMSE was 140.70 kg per hm2 for the yield component factors method under varying nitrogen and phosphorus levels in Yuzhong and it was 193.22 kg per hm2 for the grain pod ratio method. TheR2 values were 0.832 9 and 0.805 8 of yield component factors and grain pod ratio, respectively. The validation results showed that the yield component factors method was better than the grain pod ratio method in simulating oilseed flax yield formation. In view of different varieties of oilseed flax under varying experimental treatments, the yield component factors method simulated oilseed flax yield with high accuracy and versatility using the number of pods per unit area, seeds number per pod and grain weight as genetic parameters.