On-Farm Estimation of Nutrient Requirements for Spring Corn in North China
- Yi Zhanga,
- Pen Houa,
- Qiang Gaob,
- Xinping Chena,
- Fusuo Zhanga and
- Zhenling Cui *a
Estimating the nutrient requirements of corn (Zea mays L.) is crucial to facilitate fertilizer management practices and agricultural policies. Our understanding of crop nutrient uptake requirements is limited by traditional site-specific nutrient recommendation algorithms. A database composed of 1065 on-farm observations collected during 2006 to 2009 in North China was used to assess the reciprocal internal efficiencies (RIEs, kg of nutrients in plant dry matter per Mg of grain) calculated by the QUantitative Evaluation of the Fertility of Tropical Soils (QUEFTS) model under different nutrient supply conditions. We found that nutrient supply conditions have a pronounced effect on RIEs. In the absence of nutrients, the RIE values were higher than with other nutrient-supply treatments, which reflect severe nutrient deficiencies in plants. In the presence of excessive nutrients, the RIEs increased without a corresponding increase in grain yield. Hence, using the data derived from optimal nutrient supply plots with current corn hybrids, the RIEs simulated by QUEFTS, were 15.3 kg N, 2.9 kg P, and 8.3 kg K per Mg at 60 to 70% of the yield potential. These values maximized the nutrient yield-producing uptake efficiency for spring corn in North China.Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
Copyright © 2012. . Copyright © 2012 by the American Society of Agronomy, Inc.