Researches on Relationship Between Planting Density and Yield Traits of High Density Tolerance Maize

In this paper,selecting the high density tolerance maize Zhengdan958 as the test materials,an experimental design with a single factor and randomized blocks was used to study the relationship between the planting density and the yield traits of high density tolerance maize under the field planting conditions.The results indicate that the best summer planting density for high density tolerance maize varieties represented by Zhengdan958 was 4 850 plants/667 m2 in Tianjin.Among the range of planting density in this study,the yield increased with the increase of the planting density,but the yield decreased as the planting density increased when the planting density reached a certain level.Planting density has a very obvious influence on 100-kernel weight,and then the length of bare ear,grain number per row,grain number per ear.The planting density makes no notable impact on the ear length,the ear diameter,the row number per ear and the height of plant.The planting density increase made 100-kernel weight,grain number per ear and grain number per row decrease following the linear falling relation,while the yield and length of bare ear decreased firstly and then increased following the quadric parabola equation.