以小麦品种甘春27号为试验材料，研究了种植密度对小麦产量的影响，以及密度与产量和主要农艺性状的关系。结果表明，随着种植密度的逐渐增加，小麦的株高、穗长、小穗数和穗粒数以及千粒重均呈现依次递减的趋势，而穗数的变化趋势与之相反。小麦的籽粒产量随着密度的增加先增加后降低，以375万粒/hm2处理的产量最高，300万粒/hm2处理的次之，分别比产量最低的525万粒/hm2处理显著增加了4.12%、2.81%(P < 0.05)。相关分析表明，小麦的穗数和穗粒数与种植密度呈极显著相关关系(P < 0.01)，相关系数分别为0.987和-0.993，而籽粒产量与密度之间的相关系数仅为0.497(P > 0.05)。通过关联分析可知，小麦种植密度与主要农艺性状及籽粒产量的关联度从大到小的顺序依次为穗数、产量、株高、小穗数、千粒重、穗长、穗粒数，表明受密度影响最大的性状因子是穗数。虽然小麦种植密度与籽粒产量的相关性不显著，但是二者之间的关联度较大，说明合理密植仍是旱地小麦增产的关键。在本试验条件下，甘春27号小麦品种的最佳播种密度为375万粒/hm2。

The wheat cultivar Ganchun 27 was used as test material， the effects of planting density on wheat yield and the relationship between density and yield and main agronomic traits were studied. The results showed that with the increase of planting density， the plant height， ear length， spikelet number， grain number and 1 000 grain weight of wheat decreased successively， while the change trend of spike number was the opposite. The grain yield of wheat first increased and then decreased with the increasing density， the yield of 375×104 grain /hm2 treatment was the highest， and the second was 300×104 grain/hm2 treatment， which were significantly increased by 4.12% and 2.81%(P < 0.05)， respectively， compared with the lowest yield of 525×104 grain /hm2 treatment. The correlation analysis showed that there is a significant correlation between the ear number and grain number per spike with planting density(P < 0.01)， and the correlation coefficient was 0.987 and -0.993， respectively， while the correlation coefficient between grain yield and density was only 0.497(P > 0.05). Based on the gray relational grade analysis， this study found that the correlation coefficient between planting density and grain yield， agronomic characters in turn was ear number， yield， plant height， spikelet number， 1 000 grain weight， ear length and grain number per spike. The ear number was greatly affected by planting density. Although the positive correlation degree between planting density and yield was not significant， but the gray correlation between the two was higher， which indicated that rational close planting is still the key to increase wheat yield in dry land. The optimum planting density for Ganchun 27 was 375×104 grain/hm2 under this experimental condition.

S512.1

甘肃省科技支撑计划项目(1604NKCA052-1)；甘肃省高等学校科学研究成果转化培育项目(2017D-12)。