Application of controlled release urea improved grain yield and nitrogen use efficiency: A meta-analysis

PLoS One. 2020 Oct 29;15(10):e0241481. doi: 10.1371/journal.pone.0241481. eCollection 2020.

Abstract

The application of controlled release urea (CRU) has been proposed as a crucial method to reduce the adverse environmental effects induced by conventional urea (CU). Yet, a systematic and quantitative analysis on how CRU affects staple crop production including wheat (Triticum aestivum L.), maize (Zea mays L.), and rice (Oryza sativa L.) is lacking. Here, a meta-analysis was conducted to determine how CRU influences soil chemical properties, total nitrogen (TN) uptake, grain yield, and nitrogen use efficiency (NUE) of staple crop in China. The results indicated that CRU application significantly increased soil organic carbon (SOC), TN, and available nitrogen (AN) by 5.93%, 3.89% and 13.98% respectively overall, while soil pH showed no significant changes. Compared to the application of CU, applying CRU significantly increased grain yield by 7.23%, which was mainly owing to the higher TN uptake (9.13%) across all the studies. In addition, the application of CRU significantly increased NUE, nitrogen agronomy efficiency (NAE), utilization rate of nitrogen fertilizer (NUR), and nitrogen physiological efficiency (NPE) by an average of 23.4%, 34.65%, 25.83% and 15.8% respectively which could be attributed to the slow nitrogen (N) release characteristics of CRU. The positive effect of CRU on grain yield and NUE of staple crop was greatest when the content of SOC and TN were extremely low, indicating that it was most effective to improve grain production of infertile soil by applying CRU. The finding of this study indicated that the application of CRU should be promoted for grain production, especially for infertile soil.

Publication types

  • Meta-Analysis
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biological Transport / drug effects
  • Delayed-Action Preparations
  • Edible Grain / drug effects*
  • Edible Grain / growth & development
  • Edible Grain / metabolism*
  • Nitrogen / metabolism*
  • Soil / chemistry
  • Urea / pharmacology*

Substances

  • Delayed-Action Preparations
  • Soil
  • Urea
  • Nitrogen

Grants and funding

The funding of this study was The National Key Research and Development Program of China (2016YFD0201201). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript and the authors received no specific funding for this work.