摘要： 以大穗型品种泰农18（T18）和中穗型品种山农15（S15）为试验材料，在大田条件下设置4个播种密度（60，75，90，105kg／hm^2）和3个施氮水平（0，180，240kg／hm^2），研究了氮密互作对小麦花后光合特性和籽粒产量的影响，旨在寻求通过改善光合特性，获得高产的适宜施氮量和播种密度，为制定合理的栽培措施，实现高产高效提供科学依据。结果表明，密度和施氮量均显著影响冬小麦产量，且二者之间存在互作效应；密度对群体光合速率的正向效应主要体现在灌浆前中期，而施氮量的影响主要体现在灌浆中后期，高产模式下二者的互作效应使得群体光合速率在整个灌浆期保持较高的水平，群体光合性能的改善引起籽粒产量的提高。该试验条件下，泰农18的适宜的播种密度为90kg／hm^2，适宜的施氮量为180kg／hm^2；而山农15的适宜的播种密度为75kg／hm^2，适宜的施氮量为180kg／hm^2。因此，在冬小麦高产栽培过程中，可以通过调节施氮量和播种密度，充分利用氮密互作效应，提高植株的群体光合从而获得较高的籽粒产量。

关键词: 群体光合, 氮密互作, 冬小麦, 产量

Abstract: The two winter wheat eultivars used in this study were Tainong18 （T18） and Shannong15 （S15） possessing large and middle ear, respectively. Four regimes of planting density and three nitrogen rates were applied to study the interaction between nitrogen and density on photosynthesis characteristics after anthesis and grain yield to seek a balance between sowing density and nitrogen used under high yield pattern. The results showed that plant- ing density, nitrogen rate and the interaction between them had significant effects on grain yield and photosynthesis characteristics after anthesis. The effect of planting density on canopy photosynthetic rate was mainly reflected in the positive effects of early and mid grain filling stage, and the impact of nitrogen mainly in mid and late grain filling stage. The interaction between nitrogen and density maintained a high canopy apparent photosynthesis rate during the whole grain filling period under high yield pattern. In this study, the appropriate plant density and nitrogen rate of T18 were 90 kg/ha and N 180 kg/ha respectively,while for S15 were 75 kg/ha and N 180 kg/ha. Conclusively, it was possible to adjust nitrogen rate and planting density to take advantage of the interaction between them to a- chieve a higher canopy apparent photosynthesis rate and high grain yield.

Key words: Canopy apparent photosynthesis, Interaction between density and nitrogen, Winter wheat Yield

中图分类号: 

• S512.01