种植密度对‘百农418’小麦群体动态、产量及农艺性状的影响

Effect of Planting Density on Population Dynamics,Yield and Agronomic Traits of Wheat ‘Bainong 418'

为了探讨不同种植密度对‘百农418’小麦群体产量及农艺性状的影响,设置6个种植密度:225万、300万、375万、450万、525万、600万苗/hm^2,进行田间试验,研究了‘百农418’小麦的高产潜力与抗倒伏性能。结果表明,在一定范围内,成穗数随着种植密度的增加而增加,种植密度继续增加,成穗数转为下降;种植密度与成穗数呈对数曲线关系(y=259.3lnx-859.7)。低密度条件下,增加种植密度增产显著;高密度条件下,增加种植密度增产不显著直至减产;种植密度与产量呈抛物线函数关系(y=5024+22.12x-0.022x^2)。种植密度对产量三要素的影响效应表现为成穗数>千粒重>穗粒数;增加种植密度可有效增加穗数,但穗粒数、千粒重随之下降。通径分析结果表明,对产量的贡献大小依次为:穗数>千粒重>穗粒数。综合考虑高产潜力发挥和规避倒伏风险,‘百农418’小麦超高产栽培,黏壤土10月10日播种,适宜种植密度为450万~525万苗/hm^2;种植密度超过525万苗/hm^2,存在较大倒伏风险。

To discuss the effects of different planting densities on yield and agronomic traits of wheat‘Bainong418＇, six different planting densities were set up： 2.25×10^6/hm^2, 3×10^6/hm^2, 3.75×10^6/hm^2, 4.5×10^6/hm^2, 5.25×106/hm^2, 6×10^6/hm^2. In the experiment field, the potential of high yield and lodging resistance of‘Bainong418＇were studied. The results showed that, the spike number increased with the increasing planting density ina certain range, but then it decreased along with the increase of planting density; there was a log curve（y=259.3 lnx-859.7） between planting density and spike number. The yield increased significantly at low plantingdensities, but with the increase of planting density, the increase of yield was not noticeable or even the yieldreduced; and there was a parabolic function（y=5024＋22.12 x-0.022 x2） between planting density and yield. Theeffects of planting density on the three factors of yield were presented as： spike number 1000-grain weight the number of seeds per spike; and with the growth of the planting density, the number of spikes significantlyincreased while the 1000-grain weight and the number of seeds per spike decreased. The results of path analysis showed that, contributions of the three factors to yield were： spike number 1000-grain weight thenumber of seeds per spike. Taking into consideration the potential of high yield and the lodging risk,‘Bainong 418＇should be sowed in clay loam on October 10 every year, and its planting density should be set at 4.5-5.25 ×10^6/hm^2 to ensure its high yield; and there will be high lodging risk if the planting density is beyond 5.25 ×106/hm^2.