摘要： 为明确种植密度和施氮量对超高产夏玉米干物质积累和产量形成的影响,以夏玉米品种农单902为研究材料,于2013年在河北省藁城市进行了密度(设5.25万,6.00万,6.75万,7.50万,8.25万株/hm²共5个水平)和施氮量(300,375,450 kg/hm²共3个水平)的二因素裂区试验.结果表明,密度和施氮量对干物质积累量和产量性状的互作效应不显著.同一施氮量下,随密度增加,干物质积累量和每公顷穗数逐渐增加,但收获指数、穗粒数、千粒质量逐渐减小,吐丝后干物质积累量、吐丝后干物质贡献率及产量则先增加后减少.密度对果穗秃尖长、穗粒数的影响最大,对穗行数的影响最小.同一密度下,随施氮量增加,各生育时期的干物质积累量(除拔节期)、吐丝后干物质积累量、收获指数、籽粒产量及3个产量构成因素都是先增加后降低,以施氮量375 kg/hm²最高.本研究条件下,以种植密度6.75万,7.5万株/hm²,施氮量375 kg/hm²的处理产量构成因素最为协调,获得了最高的产量,分别为12 797.3,12 425.5 kg/hm².

关键词: 密度, 施氮量, 夏玉米, 干物质积累, 产量形成

Abstract: In order to clarify the effects of planting density and nitrogen fertilization rate on dry matter accumulation and yield formation of summer-sown maize,a field experiment was carried out at Gaocheng County,Hebei Province in 2013,using a summer-sown maize cultivar,Nongdan 902.The experiment was designed as split plot arrangement,with planting density as main plots (5.25×10⁴,6.00×10⁴,6.75×10⁴,7.50×10⁴,and 8.25×10⁴ plants per ha) and nitrogen fertilization rate as split plots (N 300,375,450 kg/ha).the results showed that,the interactions of planting density and nitrogen fertilization rate on dry matter accumulation and yield traits were not significant (P>0.05).Under the same nitrogen fertilization rate,the amounts of dry matter accumulation and ears per hectare increased,but the harvest index,grains per ear and 1000 grain weight decreased with the increasing density.And the amount of post-silking dry matter accumulation,the contribution percentage of post-silking dry matter to total dry matter accumulation,and grain yield firstly increased,and then decreased with the increase of density.The influence of planting density on the length of aborted part of the ear and grains per ear was the biggest,and that on grain rows per ear was the smallest.Under the same planting density,the dry matter accumulation at all growing stages (except jointing),post-silking dry matter accumulation,harvest index,grain yield and the three yield components all increased with the increase of nitrogen fertilization rate and reached the maximum at the nitrogen rate 375 kg/ha,then decreased when the nitrogen fertilization rate increased from 375 kg/ha to 450 kg/ha.Under the conditions of this study,the highest grain yields of maize,12 797.3,12 425.5 kg/ha,were achieved in the treatments with the planting density 6.75×10⁴,7.50×10⁴/ha,and nitrogen fertilization rates 375 kg/ha,respectively,in which the three yield components were coordinate.

Key words: Planting density, Nitrogen fertilization rate, Summer-sown maize, Dry matter accumulation, Yield formation

中图分类号: 

• S513.01