为了掌握陇中旱作区不同有机肥替代氮肥量和种植密度组合对马铃薯农艺性状及产量的影响，在等养分替代条件下，以陇薯7号为指示品种，研究了3个施肥水平(常规施氮、有机肥替代氮肥20%、有机肥替代氮肥40%)与3种种植密度(5.25万、6.00万、6.75万株/hm2)组合对马铃薯生长的影响。结果表明，不同有机肥替代氮肥量和种植密度组合对马铃薯农艺性状、产量及商品薯率有一定的影响；相同替氮量水平下，马铃薯产量及商品薯率随着种植密度的增加均呈先增后减的趋势；相同种植密度下，有机肥替代氮肥20%不仅改善了马铃薯农艺性状，还提高了马铃薯产量构成因素和产量。以有机肥替代氮肥20%(施N 216 kg/hm2、有机肥2 700 kg/hm2)、 种植密度为6.00万株/hm2组合处理的马铃薯折合产量最高，为28 333.3 kg/hm2，较对照常规施氮(施N 270 kg/hm2)， 种植密度为5.25万株/hm2增产12.79%；商品薯率也最高，为79.8%，较对照增加10.1个百分点。综合考虑认为，有机肥替代氮肥20%(施N 216 kg/hm2、有机肥2 700 kg/hm2)+种植密度6.00万株/hm2的组合处理为陇中旱作区马铃薯生产的最佳肥密组合。

To understand the effect of different combinations of organic fertilizer replacing nitrogen fertilizer and planting densities on the agronomic characters and yield of potatoes in the arid farming area of Central Gansu, a study was conducted using Longshu 7 as the experimental variety. Three fertilization levels (conventional nitrogen fertilization, organic fertilizer replacing 20% of nitrogen fertilizer, and organic fertilizer replacing 40% of nitrogen fertilizer) combined with three planting densities (52,500 plants/ha, 60,000 plants/ha, and 67,500 plants/ha) wereset up in this study to evaluate their effects on potato growth. The results showed that different combinations of organic fertilizer substitution and planting densities had significant impact on agronomic characters, yield, and marketable tuber rate. Under the same nitrogen replacement level, both potato yield and marketable tuber rate increased and then decreased with the increase in planting density. Under the same planting density, replacing 20% of nitrogen fertilizer with organic fertilizer not only improved agronomic characters but also enhanced the yield components and yield. The highest average yield of 28,333.3 kg/ha was obtained from the combination of 20% organic fertilizer substitution(N 216 kg/ha + 2700 kg/ha of organic fertilizer) and a planting density of 60,000 plants/ha, which was 12.79% higher than that in the conventional nitrogen fertilization treatment (N 270 kg/ha) with a density of 52,500 plants/ha. The marketable tuber rate was also the highest at 79.8%, which was 10.1 percentage points higher than that of the conventional nitrogen treatment. Based on the comprehensive analysis, the optimal combination for potato production in the arid farming area of Central Gansu is 20% organic fertilizer substitution (N 216 kg/ha + 2700 kg/ha organic fertilizer) with a planting density of 60,000 plants/ha.

S532；S147.2

定西市科技计划项目(DX2022AZ06)；定西市科技人才支持专项(DX2021AR08)；定西市科技计划项目(DX2021BZ25)。