Effects On Agronomic Traits, Yield And Quality Of Density-tolerant Spring Maize Cultivars By Different Density And Row Spacing

Density-tolerant maize cultivars that are suitable for spring sowing in medium and late mature area of Shanxi province were used as test materials. It was conducted in the agricultural station of Shanxi Agricultural University during2010and2012.The experiment was split-plot design with three factors and studied the effect on spring maize growth, yield and grain quality under different planting densities and row spacing.The densities have low, medium and high three levels. Row spacing included traditional equal line width cultivation model and different spacing ratio cultivation model. The results showed as follows:1. The plant height and ear height lifted with density increased, corn stem was thinner. It leads to the risk of lodging. When model was equel line width row spacing, plant height and ear height were higher than wide and narrow row spacing.Stem dimeter showed the opposite trend.2. There was the positive correlation between three indexes LAI, LAD, MLAI and density.In the terms of LAI and LAD, the optimal combination of density and row spacing changed because of variety, but all of three indexes maximized under high density and wide-narrow row spacing.LAI and LAD declined faster under high density and100cm+50cm row spacing in later growing stage. MLAI increased with line wider. Light transmittance of different leaf layer increased with the density increase.100cm+50cm row spacing leaded to light waste because the lines were too wide. This shows that coordinating the relationship between density and row spacing is very important to the raise of plant light interception.3. Dry matter accumulation showed a trend of singlet growth. There was negative correlation between density and dry matter accumulation. High density played a bigger role in promoting the center growth during different growing period. Before elongation stage, dry matter accumulation increased with lines wider and100cm+50cm row spacing benefited dry matter accumulation under high density; since elongation stage, it decreased with lines wider and66.6cm+33.3cm row spacing benefited dry matter accumulation.4. Group yield significantly or high significantly improved with density increased.Yield firstly increased and then decreased with line spacing wider. It concluded that under the testing condition super-high yield combination of Xianyu335was81000plants per hectare with66.6cm+33.3cm cultivation model; high yield combination of Dafeng30was82500plants per hectare with66.6cm+33.3cm cultivation model; super-high yield combination of Qiangsheng51, Dafeng26and Luyu36all was82500plants per hectare with66.6cm+33.3cm cultivation model.5. Density and row spacing had significant or high significant effect on grain protein content, it decreased and increased with density increased and lines wider respectively.Density and row spacing had small influence on grain starch content and oil content.lt concluded that under the testing condition high protein combination of Xianyu335was45000plants per hectare with60cm+40cm cultivation model; high protein combination of Dafeng30was52500plants per hectare with66.6cm+33.3cm cultivation model; high protein combination of Qiangsheng51. Dafeng26and Luyu36all was52500plants per hectare with100cm+50cm cultivation model.