油菜生育期模拟模型研究

A Process-Based Model for Simulating Phenological Development in Rapeseed

【目的】以油菜生理生态过程为基础,通过定量分析油菜对温度(包括春化作用)和光周期的反应,构建以生理发育时间为尺度的油菜生育期模拟模型。【方法】每日生理发育时间由每日生理效应累积形成,而每日热效应、春化效应、光周期效应与品种灌浆速率互作共同决定每日生理效应大小。模型通过引入温度敏感性、生理春化时间、光周期敏感性和基本灌浆因子4个参数反应不同油菜品种的遗传差异,从而使得每个油菜品种达到特定生育时期所需生理发育时间恒定。利用不同地点、播期、品种和肥料处理的试验数据对所建模型进行了校正和检验。【结果】播种到抽薹、初花、终花、成熟期的模拟值与预测值RMSE(根均方差)分别为1.37%、1.52%、2.68%和1.12%。【结论】表明模型具有较好机理性和可靠性。

[ Objective ] Based on the eco-physiological processes of rapeseed development, a simulation model for predicting phenological stages of oilseed rape （Brassica napus L.） was developed with the physiological development time （PDT） as time scale and by quantifying the effects of temperature （including vernalization） and photoperiod on oilseed rape. [Method] The interaction among daily thermal effectiveness, photoperiod effectiveness, vernalization effectiveness and filling rate determined the daily physiological effectiveness, which was accumulated to obtain physiological development time. Four specific genetic parameters as temperature sensitivity, physiological vernalization time, photoperiod sensitivity and basic filling duration factor were added to adjust the genotypic differences in rapeseed development so that all different varieties could reach the same physiological development time at a given development stage. [Result] Based on the experiments with different sites, sowing dates, varieties and fertilization levels, the＇stages from emergence to stem elongation, onset of flowering, end of flowering and maturity were validated with the root mean square error （RMSE） of 1.37%, 1.52%, 2.68%, and 1.12%, respectively. [Conclusion] Thus, the present model appears to provide a mechanistic description and reliable prediction of development progress in rapeseed.