大豆种植密度与施肥水平及产量有着密切关系,但并不是密度加大,施肥水平提高产量和经济效益也相应的提高,为了寻找最佳密度下配合施肥水平,以达到最高产量和经济效益。我们于1990～1991两年设计研究大豆的密度与肥料联合增产效应函数的研究试验。 1 试验设计方法采用三因素饱和最优设计(“311”设计)法。设计三 Soybean planting density and fertilization level and yield are closely related, but not increased density, fertilization level to improve yield and economic benefits also increased accordingly, in order to find the best density with fertilization level, in order to achieve the highest yield and economic benefits. We in 1990 ~ 1991 two years to study the design and study of soybean density and fertilizer yield-increasing effect of the experimental study. A trial design method using three-factor optimal design ( “311 ” design) method. Design three