不同春玉米品种干物质生产和子粒灌浆对种植密度的响应

以中单909(ZD909)、吉单209(JD209)和内单4号(ND4)为材料,设置5个种植密度,研究不同种植密度下春玉米子粒产量、干物质积累和灌浆特性的响应特征。结果表明,3个品种的子粒产量均随种植密度提高呈先增加后下降趋势,ZD909在各密度下的产量均高于JD209和ND4。ZD909在9.00万株/hm2下达到最高产量,JD209和ND4在6.75万株/hm2下达到最高产量。群体干物质积累量随密度增加而显著提高,但收获指数呈下降趋势。随密度的提高,ZD909的干物质递增幅度高于JD209和ND4,收获指数下降幅度小于后两个品种。子粒最大灌浆速率、灌浆持续时间均随种植密度的增大而减小,ZD909灌浆持续期、活跃灌浆期均显著长于JD209和ND4。ZD909的生产力受种植密度的不利影响程度低于JD209和ND4,密植增产潜力大。

Differences in Responses of Biomass Production and Grain-filling to Planting Density Between Spring Maize Cultivars

Three cultivars as the materials, under five planting densities. The differences in biomass production and grain filling to planting density between spring maize cultivars were studied. The results showed that grain yields firstly increased to the highest values and then declined significantly with the increase in planting density. As comparison with JD909 and ND4, higher grain yields were found under all planting densities of ZD909. Along with planting density increasing, plant population dry matter accumulation increased significantly, however, harvest index (HI) decreased significantly. Population dry matter accumulation and HI for ZD909 were higher than those of JD209 and ND4 under dense planting. The maximum grain-filling rate and duration declined along with the planting densi-ty increasing, and higher maximum grain-filling rate and duration were found in ZD909 than JD909 and ND4. The results indicated that the negative impacts of dense planting on maize yielding functions were lower for ZD909 than the JD209 and ND4, suggesting a higher yielding potential.