为明确不同种植密度对晋糯20号玉米产量和商品性的影响，给该品种的推广提供技术支撑。采用二因素裂区设计，主区为4个密度梯度(4.50 万、5.25 万、 6.00 万、6.75 万株 /hm2)，副区为4个行距(40 cm、50 cm、60 cm、40 cm+60 cm)，共16个处理进行田间试验。结果表明:密度对晋糯20号鲜穗重、百粒重、穗长、产量影响极显著，行距对鲜穗重、产量影响差异，密度行距互作对产量影响极显著。随种植密度的增加，晋糯20号单株干物质呈下降趋势，鲜穗产量呈先增后降再增的变化趋势；密度为 5.25 万株/hm2 处理下，产量最高，穗长、穗质量和百粒重也表现较好，此密度下配40 cm+60 cm行距，鲜穗产量可达(13 992.90±142.50) kg/hm2，优级穗率最高，为92.5%。此外，密度对优级穗率影响显著，宽窄行可以提高优级穗率。建议在晋糯20号的种植过程中，采用 5.25 万株 /hm2 配40 cm+60 cm行距，可明显提高产量与商品品质。

In order to determine the effects of different planting densities and row spacing on yield and product quality of maize variety Jinnuo 20 and to provide technical support for the promotion of this variety, a two-factor split plot design was adopted, the main plot was divided into 4 density gradients (45 000, 52 500, 60 000, and 67 500 plants/ha), and the sub-plot was divided into 4 row spacing (40 cm, 50 cm, 60 cm and 40 cm+60 cm), therefore sixteen treatments were studied. The results showed that density had significant effects on fresh ear weight, 100-grain weight, ear length and yield of Jinnuo 20, whereas row spacing had significant effects on fresh ear weight and yield. The interaction of density and row spacing had an extremely significant effect on yield. With the increase of planting density, the dry matter per plant decreased, and the fresh ear weight increased first, then decreased and then increased. The yield was the highest when the density was 52 500 plants/ha and the ear length, ear quality and 100-grain weight were also ideal. Under this density, the yield could reach 13 992.90±142.50 kg/ha with 40 cm+60 cm row spacing applied and the rate of excellent ear was the highest, i.e. 92.5%. In addition, density had a significant effect on the rate of excellent ear, and narrow row width could improve the rate of excellent ear. Therefore, it is suggested to adopt 52 500 plants/ha with 40 cm+60 cm row spacing in the demonstration and promotion process of Jinnuo 20, which could improve the yield and commodity quality significantly.

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中央引导地方科技发展资金项目(YDZJSX2021C021)；忻州市重点研发计划(20200319)。