基于气候因子效应的冬小麦籽粒蛋白质含量预测模型

 在对4个生态区、6个不同品质类型小麦品种在不同播期下的试验数据进行系统综合分析的基础上，建立了冬小麦籽粒蛋白质含量的生态预测模型。通过分析籽粒蛋白质含量与气候因子的相关关系，确定了显著影响蛋白质含量的5个气象因子：开花至成熟期的日平均温度、平均日较差、总日照时数、总降雨量与积温。经逐步回归分析表明，高蛋白品种籽粒蛋白质含量主要受开花至成熟期间的平均日较差的影响；在日较差变异系数<5%的生态环境下，则决定于开花至成熟期日均温与总日照时数的互作。中蛋白品种蛋白质含量取决于开花至成熟期的总日照时数；而低蛋白品种由开花至成熟期的日均温、总降雨量与总日照时数共同决定。影响蛋白质含量的日较差与光照效应因子，分别通过与开花至成熟期的平均日较差及总日照时数间的线性关系建立模型；温度效应因子则通过与日均温的二次曲线关系建立模型。开花至成熟期的降雨量>50 mm时，降雨效应因子呈现二次曲线的变化模式；开花至成熟期的降雨量<50 mm时，则呈线性变化。运用南京地区3个品种的播期试验，6个生态区8个小麦品种的品质生态试验以及南京和徐州两地40个小麦品种的试验数据对模型进行了检验，各品种与各生态点的RMSE值均小于10%，表明模型能够可靠地预测不同品质类型冬小麦在不同环境条件下的籽粒蛋白质含量。

An Ecological Model for Predicting Grain Protein Content in Winter Wheat

Based on the experiments conducted at four eco-sites with six wheat genotypes differing in grain protein content, an ecological model for predicting grain protein content in winter wheat was established. Analyses on correlations between grain protein content and climatic factors showed that five factors, i.e. mean temperature (Tmean), difference of diurnal temperature (DT), total rainfall (R), total sunshine (S) and growing degree days (GDD) from anthesis to maturity, determined the variation of grain protein content. By stepwise regression analysis, grain protein contents of high-protein varieties depended on DT under the environment with significant DT variation, but on interaction of Tmean and total sunshine under the environment with DT variation less than 5%. For middle-protein and low-protein varieties, grain protein content depended on the total sunshine, and interaction of Tmean, R and S. In the model, the effectiveness factors of DT and sunshine depended on the linear relationship between grain protein content and DT, total sunshine. The temperature factor was determined by the quadratic relationship between protein content and Tmean. The factor of rainfall linearly changed with total rainfall from anthesis to maturity if R was less than 50mm, whereas quadratic equation was established when R was more than 50mm. The model was tested by the different data from three experiments: the first experiment was conducted under three sowing dates with three varieties, the second at six eco-sites with eight winter varieties, and the third at two sites with forty varieties. The RMSE values of all varieties and eco-sites tested were less than 10%. The results indicate a good fit between the simulated and observed values of grain protein contents, thus a reliable prediction for the grain protein contents of different winter wheats under different environments can be obtained.