耐密玉米杂交种密度效应研究

研究了郑单958和先玉335在山西长治地区生态条件下的种植密度效应，分析了光合特性和产量及其构成因素。结果表明：郑单958的适宜栽培密度为7.50万～9.00万株/hm²，在此密度下产量为13 056.0～13 526.0 kg/hm²，叶面积指数在抽雄至蜡熟期为4.2～6.2，蜡熟至完熟期保持在2.6左右，经济产量形成期的群体光合势占总光合势的67.53%，全生育期平均净同化率为7.2～8.3 g/(m²·d)；最佳产量结构为单位面积穗数7.50万～8.82万穗/hm²、穗粒数524～466粒、千粒重332.0～329.0 g。先玉335的适宜栽培密度为7.50万株/hm²，在此密度下产量为13 714.5 kg/hm²，叶面积指数在抽雄至蜡熟期4.0～5.2，蜡熟至完熟保持在2.6左右，经济产量形成期的群体光合势占总光合势的66.42%，全生育期平均净同化率为7.9 g/(m²·d)；最佳产量结构为单位面积穗数7.50万穗/hm²、穗粒数538粒、千粒重339.9 g。

Plant Density Effects on Compact Maize Morphology and Yield Components

In this paper, two maize hybrids(Zhengdan958 and Xianyu335) were used to study the plant density effects on photosynthesis characteristic, yield and its component in Changzhi, Shanxi province. The results showed that the suitable plant density for Zhengdan958 was 75 000 to 90 000 plants/ha, grain yield from 13 056.0 to 13 526.0 kg/ha. The LAI(leaf area index) was 4.2 to 6.2 and 2.6 respectively during the time of tasselling to kernel-waxy-ripe stage. The proportion of photosynthesis at economic yield forming stage to total photosynthesis was 67.53%. The average of net assimilating rate in whole growth period was 7.2 to 8.3 g/(m²·d). The best yield components for Zhengdan958 were 75 000 to 88 200 ears/ha, 524 to 466 kernel number, and 332.0 to 329.0 g for 1 000-kernel-weight. The suitable plant density for Xianyu335 is 75 000 plants/ha, with grain yield of 13 714.5 kg/ha. The LAI was 4.0 to 5.2 and 2.6 respectively during the time of tasseling to kernel-waxy-ripe stage. The proportion of photosynthesis at economic yield forming stage to total photosynthesis was 66.4%. The average of net assimilating rate in whole growth period is 7.9 g/(m²·d). The best yield components for Xianyu335 were 75 000 ears/ha, 538 kernel number, and 339.0 g for 1 000-kernel-weight.