Nutrient Management and Optimized Fertilization on Wheat and Maize in Hebei Province

The project has been focusing on Nutrient Expert based fertilizer recommendation since 2010

IPNI-2009-CHN-HE26

02 Feb 2007

2006 Annual Interpretive Summary


The amount of K off-take by crops grown in Hebei Province is steadily increasing and crop responses to K application are common each year. This long-term study continues to examine the effect of K application and balanced fertilization (BF) on wheat and corn.

The fixed-site study for K use in a winter wheat/summer corn rotation system indicated that K has become as significant in sustaining high summer corn yields as was previously found in winter wheat. Addition of 150 kg K2O/ha, and 150 kg K2O/ha plus winter wheat straw increased winter wheat by 6% and 9%, and summer corn yield by 24% and 24%, respectively. Application of K since 1982 increased both available K and slowly-released K in the top 20 cm of soil from 83 to 148 mg available K/kg soil and 917 to 1,032 mg slowly-released K/kg soil. As a result of no potash application in 2005, those values declined to 81 mg available K/kg soil and 910 mg slowly-released K/kg soil. These results demonstrated that K application plays a key role in maintaining crop yield increases and soil K supplying capacity.

A separate field trial on summer corn was conducted in Zhengding County. Based on the average check yield of 5.5 t/ha and net income of US$710/ha with 240-75-0 kg N-P2O5-K2O/ha, corn yield increased by 17%, 27%, 33%, and 21%. Net income increased by 18%, 26%, 30%, and 10% with 75, 150, 225, and 300 kg K2O/ha, respectively. While there is great opportunity to increase corn yield with K application, excessive K use can decrease both yield and benefit. Another separate field experiment in Xinji County found the optimal treatment of 240-75-150 kg N-P2O5-K2O/ha plus 40 zinc sulfate (ZnSO4)/ha produced the highest corn yield of 8.6 t/ha and highest net benefit of US$1,159/ha. Omission of N, P, and K respectively reduced yield by 18%, 8%, and 12%, and net income by 12%, 11%, and 14%. Hebei-NMBF