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

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.

Role of zinc-coated urea fertilizers in improving nitrogen use efficiency, soil nutritional status, and nutrient use efficiency of test crops

“…The present study showed that in the first 109 days of the experiment dissolved organic carbon (DOC) was significantly improved in coated urea treatments in comparison to the control treatment which might be due to readily available organic compounds like plant root exudates, decomposable organic matter, and sloughed off root cap cells (Ghosh et al, 2012). DOC results of the current experiment are also in line with the findings of Zhu et al (2020) who reported significant improvements in DOC as a result of coated urea fertilizers. Several other studies also support the fact that the application of N fertilizers improves DOC and subsequent crop growth and production (Mehmood et al, 2018;Liyuan et al, 2020).…”

Grain Yield and Nitrogen Use Efficiency Vary with Cereal Crop Type and Nitrogen Fertilizer Rate in Ethiopia: A Meta-Analysis

“…The supply of soil nutrients in already fertile soils slightly enhances or even declines the grain yield. Another study revealed a higher yield increase under P-fertilizer application when the soil phosphorous is low [51] and under controlled-release nitrogen application when the SOC content is low [52]. Therefore, it was observed that the N-application in Ethiopia significantly increases crop yield, although the magnitude is affected by several explanatory factors and crop type.…”

Oil-Based Polymer Coatings on CAN Fertilizer in Oilseed Rape (Brassica napus L.) Nutrition

“…The application of controlled-release fertilizers (CRFs) is one way to improve nutrient use efficiency, reduce nitrogen loss, and contribute to minimizing environmental pollution, providing a better compromise among soil fertility, yield, and grain quality [ 20 , 21 , 22 ]. CRFs prove the potential to decrease the fertilizer application rate by 20% or 30% of the recommended value to achieve the same yield [ 23 ].…”