Abstract: 【Objective】To study the regulation of soil subsoiling and planting density on photosynthetic characteristics of spring maize population,and provide theoretical basis for high-yield and high-efficiency spring maize production.【Methods】In the experiment,Weike 702 and Xianyu 335 were used as test materials,and planting densities were 45 000,60 000,75 000,and 90 000 plants/hm²,and two treatments of subsoiling and non-subsoiling(CK)were conducted. Random block design was used to analyze effects of soil subsoiling on canopy photosynthetic characteristics and yield of spring maize under different planting densities.【Results】Under the four planting density levels,the soil subsoiling treatment all improved the photosynthetic performance indicators of the spring maize canopy LAI,ChlT,Pn,Tr,and effectively increased the number of effective maize,the number of grains per ear,and the thousand grain weight index.The increasing range of subsoiling treatments increased with the increase of planting density. The yield of Weike 702 and Xianyu 335 reached the maximum at 75 000 plants/hm² in the subsoiling treatment,and the yield increased by 9.08% and 7.82%,respectively,compared with the CK.【Conclusion】Weike 702 and Xianyu 335 got the highest yield under the planting density of 75 000 plants/hm² and soil subsoiling,and the largest increase in yield and the best subsoiling effect,which maximized the potential of the varieties.

Key words: Spring maize, Soil subsoiling, Planting density, Photosynthetic characteristics, Yield