Table of Contents
ISRN Agronomy
Volume 2012, Article ID 294514, 9 pages
http://dx.doi.org/10.5402/2012/294514
Research Article

Evaluation of In-Season Nitrogen Management for Summer Maize in North Central China

1Ministry of Agriculture Key Laboratory of Crop Nutrition and Fertilization, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
2Resource and Environment Institute, Hebei Academy of Agricultural Sciences, Shijiazhuang 050031, China
3Dryland Farming Institute, Hebei Academy of Agricultural Sciences, Hengshui 053000, China

Received 10 August 2011; Accepted 25 September 2011

Academic Editors: J. A. Casaretto and J. Hatfield

Copyright © 2012 S.-C. Zhao et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

We conducted field experiments in which nitrogen (N) was applied to summer maize at different rates and different basal/topdressing ratios. The experiments were carried out in 2009 in Hengshui and Xinji, Hebei province, China. The results showed that basal application of N was necessary for maize growth in early summer and for high grain yields. For the Hengshui and Xinji sites, 30 and 57 kg N ha−1, respectively, would meet the N demands of maize before 7-leaf stage. The total rates of 120 and 180 kg N ha−1, respectively, would maximize grain yields, and in-season N management based on crop N demands and soil N supply could reduce N inputs by more than 50% in Hengshui and 25% in Xinji, respectively, in one maize growth season, compared with farmers' practice, but the sustainability of the optimum N rates for maximum grain yield of next seasons crop needs to be further studied. Optimum N management should take into account the existing nutrient conditions at each site, soil fertility and texture, and crop demands.