Influence of Planting Densities to Agronomic Traits and Yield of Dryland Corn

To get an optimum planting density for corn in dryland,Xianyu 335 as local main corn variety was used and five densities were set to study agronomic traits,yield and yield components,and water utilization efficiency under sheep manure application in deep soil.The result showed that,along with the increase of planting density,plant height,ear height and rare ear length increased significantly,while stem diameter,ear length,ear diameter and weight per 100 grains decreased.The yields increased firstly and decreased later.A regression equation of Y=-504.73X2+6 241.3X-7 234.1(R2=0.816 2) was achieved.Based on the regression equation,the optimum planting density was 67 500 plants/hm2,the theoretical yields was 12 326.2 kg/hm2 and the highest water use efficiency 27.06 kg/(mm·hm2).