本文研究了晋中盆地麦—秋两作栽培体系中特早熟夏玉米冀承单 3号的密度与经济产量及产量性状的关系 ,结果表明 :(a)经济产量—密度方程 ,单位面积穗数—密度方程呈二次抛物线型 ;百粒重—密度方程 ,穗粒数—密度方程呈直线下降型。 (b)密度 5 0 0 0～ 5 2 0 0株 / 6 6 7 ,空秆率 1 0 %左右 ,单位面积成穗45 0 0～ 46 0 0穗 / 6 6 7 ,穗粒数 44 0～ 45 0 ,百粒重 1 6 5～ 1 7 5g为最佳产量结构 In this paper, we studied the relationship between the density, the yield and the yield of the early maturing summer maize Jizheng Dan No. 3 in the wheat-autumn two-cropping system in Jinzhong Basin. The results showed that: (a) The economic yield-density equation, spikelets per unit area - The density equation shows a quadratic parabola; the equation of 100-grain weight-density and the number-density equation of grain-spikes show a linear descending pattern. (b) The density ranged from 500 to 5200 plants / 667 with an empty stalk ratio of about 10%. The unit area was 4560 ~ 4600 spikes / 45 0, 100 grain weight 165 ~ 157g is the best yield structure