粮饲通用型玉米产量高品质优良，在生产上应用越来越广泛。为探讨其适宜种植密度，以四个粮饲通用型玉米品种（登海605、登海圣丰168、青农118和天泰366）为试验材料，研究四个种植密度（4.5×104、6.75×104、9×104和11.25×104株/公顷）对粮饲通用玉米产量和饲用品质的影响。结果表明：在一定范围内随着种植密度的增加，玉米的株高和穗位高增加，茎粗减小，鲜草和干草产量呈增加的趋势。天泰366的产量在9×104~11.25×104株/公顷密度时最高，其它三个品种在11.25×104株/公顷密度时产量最高。种植密度对中洗涤纤维影响不显著，对酸性洗涤纤维、粗蛋白、淀粉和粗脂肪的影响在不同品种间变化趋势不一致。根据粗饲料分级指数，登海605、青农118和登海圣丰168适宜种植密度分别为11.25×104、9×104和9×104株/公顷，而天泰366在不同种植密度时粗饲料分级指数无显著差异。因此，综合生物产量和粗饲料分级指数，在黄淮海地区天泰366和登海605推荐种植密度分别为9×104和11.25×104株/公顷，青农118和登海圣丰168推荐种植密度均为9×104~11.25×104株/公顷。

Abstract: The foodstuff maize is sufficient in biomass yield and nutritional quality, which is widely used in agricultural production. Our aim was to compare yield and forage quality of Zea mays with four planting density (4.5 × 104, 6.75 × 104, 9 × 104 and 11.25 × 104 plants/hm2) and four varieties (Denghai 605, Denghai Shengfeng 168, Qingnong 118, and Tiantai 366), therefore obtaining the optimal sowing density and variety in Huanghuaihai area. The plant height and ear height of the four varieties increased accompanied by increased planting density within a certain density range. However, the increased planting density significantly reduced stem diameter. With the increase of planting density, the yield of fresh grass and hay increased. Tiantai 366 got the highest forage yield at the density of 9 × 104 -11.25 × 104 plants/hm2, and the other three varieties got the highest forage yield at the density of 11.25 × 104 plants/hm2. The neutral detergent fiber was not significantly changed across planting density. With the increase of planting density, the change trend was different in acidic detergent fiber, crude protein, starch and crude fat among four varieties. According to the raw fodder grading index, the suitable planting density of Denghai 605, Qingnong 118 and Denghai Shengfeng 168 was 11.25 × 104 plants/hm2, 9 × 104 plants/hm2, and 9 × 104 plants/hm2. There was no significant difference in raw fodder grading index of Tiantai 366 among four planting densities. Based on forage yield and raw fodder grading index, the optimal sowing densities of Tiantai 366 and Denghai 605 were 9 × 104 plants/hm2 and 11.25 × 104 plants/hm2, respectively. For Qingnong 118 and Denghai Shengfeng 168, the optimal sowing densities were 9 × 104-11.25 × 104 plants/hm2.

山东省农业良种工程项目(2019LZGC002-2)；国家牧草农业产业技术体系(CARS-34)；山东省现代农业产业技术体系牧草创新团队(SDAIT-23-01)；青岛农业大学博士基金(1120007)