Coordinated variation of yield and grain protein content in winter wheat and strategies of irrigation and fertilizer application

Chino. 揭示冬小麦产量与籽粒蛋白质含量协同变化特点，为小麦高产优质栽培决策提供依据。根据盆栽水肥和田间肥料试验数据建立冬小麦产量和籽粒蛋白质含量关于土壤水分含量及氮磷肥的单因素和两因素效应函数，通过对函数曲线变化状态及其特点的分析，揭示小麦产量和蛋白质含量在不同水肥条件下的协同变化特点及其条件，并据此确定各种条件下高产优质的水肥管理方案。低肥和中肥（或土壤水分含量为田间最大持水量的50%和60%）条件下，产量和籽粒蛋白质含量随土壤水分含量（或施氮量）增加的曲线分别为凸型和凹型。蛋白质含量最低值和产量最高值之间对应的施氮量为产量和蛋白质含量在土壤水分含量为田间最大持水量的50%和60%条件下协同变化的施氮量区间。在高肥和土壤水分含量为田间最大持水量的70%和80%条件下，产量和蛋白质含量曲线均为凸型，蛋白质含量达到最大值之前对应的土壤水分含量为高肥条件下产量和蛋白质含量协同变化区间；产量达到最大值之前对应的施氮量为土壤水分含量为田间最大持水量的70%和80%条件下产量和蛋白质含量协同变化区间。在一定的水肥条件下，小麦产量和蛋白质含量协同变化是可能的。用极差变换将产量和蛋白质含量理论值标准化，其标准值曲线的交点即为二者的最佳结合点。用等值线图描述产量和蛋白质含量的水氮和氮磷两因素效应，分析产量和蛋白质含量变化规律及其关系，确定实现一定生产目标的水肥管理方案。这为小麦高产优质水肥调控提供了一种行之有效的方法。

Inglés. The aim of the paper was to reveal the coordinated variation of winter wheat yield and grain protein content. Based on pot and field experiments, the effect functions of winter wheat yield and grain protein content were established, in which the soil water content and nitrogen and P2O5 were taken as the effect factors. The function curves revealed the coordinated variation of yield and grain protein content with increase of soil water content (or nitrogen) at different nitrogen levels (or soil water content). And the management plans for high yield and high quality of winter wheat were made according to the coordinated variation of yield and grain protein content. The variation curves of yield and grain protein content with soil water content (or nitrogen) were convex and concave respectively in low fertility and medium fertility (or soil water content were 50% and 60% of field maximum moisture capacity). The nitrogen between minimum protein content and maximum yield were the nitrogen of coordinated variation of yield and grain protein content in 50% or 60% of soil water content. The variation curves of yield and grain protein content with soil water content (or nitrogen) were convex in high fertility (or soil water content were 70% and 80% of field maximum moisture capacity ), and the soil water content (or nitrogen levels) before maximum protein content (or maximum yield) were the soil water content (or nitrogen levels) of coordinated variation of yield and grain protein content. Coordinated variation of yield and grain protein content was possible in suitable condition. The simulated value of yield and grain protein content were standardized using polar difference variant, and the intersection point of curves of the standardized variables was the best combination of yield and grain protein content. The effect of yield and grain protein content with soil water content and nitrogen (or nitrogen and P2O5) was described by isopleth. On the basis of the isograms, we analyzed the variation law of yield and grain protein content with soil water content, nitrogen and P2O5, . We made management plans for high yield and high quality.