Effects of Different Planting Densities on Grain Yield,LAI and Dry Matter Accumulation of Summer Maize

The purpose of this research is to explore the effects of different planting densities on the grain yield,LAI and dry matter accumulation of summer maize,and provide theoretical basis and technical support for the further enhancement of per unit area yield of summer maize. Maize varieties TT 33,TT 55 and ZD 958 were used as experimental materials,and six planting densities( 6. 00 × 104,6. 75 × 104,7. 50 × 104,8. 25 × 104,9. 00 × 104,and 9. 75 × 104 plant / hm2) were set. The results showed that the grain yield of maize significantly increased with the increase in planting density within limits; while it gradually decreased with the increase in planting density beyond a certain value. The LAI increased with the increase in planting density,and it reached a peak at silking stage,and then began to reduce. The total dry matter accumulation significantly increased as planting density gradually increased. In conclusion,under this experimental field conditions,the appropriate planting densities of TT 33,TT 55 and ZD 958 were about 8. 25 × 104,8. 25 × 104 and 7. 50 × 104 plant / hm2 respectively.