春玉米果穗性状对种植密度的响应研究

2015~2016年,选用耐密、适应性广的高产品种先玉335、郑单958和KX3564为试验材料,设置从15 000~180 000株/hm~2不同密度处理,研究种植密度对玉米产量及果穗性状的影响。结果表明,在不同种植密度下,各品种产量均随着密度呈先增加后减少的趋势,符合二次曲线关系。由拟合方程得到最高产量为19 259.55 kg/hm~2,低于实际最高单产,3个品种连续两年在90 000株/hm~2密度下获得最高产量。相关分析显示,单穗粒重、行粒数与产量呈极显著正相关。随着密度的升高,穗行数、行粒数、穗长、穗粗、单穗粒重下降,秃尖长增加;百粒重、单穗粒重与密度呈一般线性关系,且都呈极显著负相关。在保证合理密植条件下,通过协调好穗长与行粒数、穗粗与行粒数、百粒重与穗行数之间的关系,可以在当前密度下获得高产。

Study on the Response of Ear Traits to Planting Density in Spring Maize

During the 2015-2016, the high-yielding varieties with high density tolerance and wide adaptability of Xianyu335, Zhengdan958 and KX3564 were used as experimental materials. Set from 15 000 plant/ha to 180 000 plant/ha different density treatments to study of planting density on yield and ear characteristics in maize. The re-sults showed that under different planting density, the yield of each variety showed a trend of increasing first and then decreasing, and it conformed to the quadratic curve. The maximum yield of 19 259.55 kg/ha by fitting equation is lower than the actual maximum yield. Three varieties of two consecutive years at 90 000 plant/ha density were ob-tained the maximum yield. Correlation analysis showed that, there was a significant positive correlation between ker-nel weight per ear and kernel number per row and yield. With the increase of density, kernel rows per ear, ker-nel number per row, ear length, ear diameter, kernel weight per ear were decreased, and bare tip length was in-creased. Among them, the kernel number per row, ear length and density were the second order function, and 100 kernel weight and kernel weight per ear were linearly related to the density, and all of them showed a significant neg-ative correlation. In order to ensure the rational close planting conditions, through the coordination of the ear length and kernel number per row, ear diameter and kernel number per row, 100-grain weight and the relationship be-tween the kernel rows per ear, such fine traits easier to obtain high yield under current density.