【摘要】 通过双重组合正交旋转回归设计试验,明确了影响黄淮及长江中下游地区夏大豆产量的主要因素依次为八月降雨量（X₂）、施磷量（X₄）,施氮量（X₃）等;建立了六元二次目标函数模型;提出了适于黄淮及长江中下游地区实用的25个优化综合农艺措施,探讨了单因素、二因素的边际产量效应。更多还原

【Abstract】 Orthogonal gyrating design was carried out to study the main factors that affect the soybean yield in Huang-Huai Plain and the middle and lower reaches of Yantze River. The experiment rsvealed that the order of the key factors were rain fall in August(X2),calcium superphosphati(X1),and urea (X3).A objective function model of yield that are suitable to the 25 ecological conditions in the above areas were suggested. And a primary study was made on the bound-yield effects of single or two factors.更多还原