摘要：为完善陇中旱作玉米高产高效栽培技术，本试验以先玉335为试验材料，在全膜双垄沟播种植条件下，研究4个密度水平（D1：4.5×104、D2：5.25×104、D3：6.0×104、D4：6.75×104株?hm-2）对旱地春玉米形态指标、灌浆特征、干物质积累、产量及其构成因素的影响。结果表明，密度增加，株高表现为先增大后减小的趋势，处理间无显著差异，地上部分干物质积累量和叶面积指数提高，而营养物质向籽粒转运的效率降低；不同处理下产量受有效穗数的影响较大，随着密度增大,群体有效穗比例由77.00%降低至69.00%；灌浆速率和灌浆时间共同影响百粒重，密度较低时，籽粒最大灌浆速率出现所用天数提前，有助于籽粒灌浆过程提前完成；随着密度增加，穗行数和行粒数均表现为增大趋势，而百粒重先增大后减小，密度超过5.25×104株?hm-2后，百粒重逐渐下降。因此，在本试验条件下，种植密度为4.5×104株?hm-2左右时，可以较好的协调玉米群体和个体生长关系之间的矛盾，实现籽粒高产和水分高效利用的目标。

Abstract：To improve the high-yield and high-efficiency cultivation technology of dry-farming maize in the middle of Gansu, this experiment used Xianyu 335 as the test material and studied 4 density levels (D1: 4.5×104, D2: 5.25×104, D3: 6.0×104, D4: 6.75×104 plants?hm-2) on the morphological index, filling characteristics, dry matter accumulation, yield and its constituent factors of dryland spring corn. The results showed that with the increase in density, the plant height showed a trend of first increasing and then decreasing. There was no significant difference between the treatments. The dry matter accumulation and leaf area index of the aerial part increased, while the efficiency of nutrient transfer to the grain decreased; Yield is greatly affected by the number of effective ears. As the density increases, the effective ear percentage of the population decreased from 77.00% to 69.00%; the filling rate and filling time affect the 100-grain weight together. When the density was low, the maximum grain filling rate appeared earlier, which was helpful for the grain filling process to be completed in advance. With the increase of density, the number of rows of ears and the number of rows of grains both showed an increasing trend, while the weight of 100-grain first increases and then decreases, When the density exceeded 5.25×104 plants?hm-2, the 100-grain weight gradually decreased. Therefore, under the experimental conditions, when the planting density is about 4.5×104 plants?hm-2, the contradiction between the growth relationship between the maize population and the individual can be better coordinated, and the goals of high grain yield and efficient water use can be achieved.

甘肃省国际科技合作基地项目（GSPT-2018-56），甘肃省干旱生境作物学国家重点实验室主任基金（GHSJ-2019-Z4），国家自然科学基金（31761143004）。