Nitrogen Fertilizer Recovery and Partitioning Related to Soybean Yield

Author(s)

Pierozan Junior, Clovis ; Favarin, Jose Laercio ; Lago, Bruno Cocco ; Munhoz de Almeida, Rodrigo Estevam ; de Oliveira, Silas Maciel ; Ocheuze Trivelin, Paulo Cesar ; Oliveira, Felipe Brendler ; Gilabel, Amanda Prado

• Document type: Journal article
• Source: JOURNAL OF SOIL SCIENCE AND PLANT NUTRITION; v. 20, n. 4, p. 13-pg., 2020-08-24.

Abstract

This study checked the nitrogen (N) uptake, fate of the N fertilizer, fertilizer recovery efficiency (FRE) and the residual amount of N fertilizer in the soil via(15)N-labelled fertilizer applied to soybean (Glycine maxL. Merr.), to explain any differences in the yields. Two soybean field experiments were established in Brazil, one conducted in a tropical (Trop) zone located at Cerrado Biome and the other in a subtropical (Subt) environment. The experimental design was a 2-factor in randomized complete block with four replications. Five doses of N (0, 20, 40, 80 and 120 kg ha(-1)) were applied at two soybean growth stages (VE and R3). For all treatments, except No-N,N-15-labelled fertilizer was used. The N uptake and the amount of N fertilizer were analysed in the roots, shoots, grains and whole plant, the FRE and yield by soybean, and the residual of fertilizer in the soil. The total N uptake (Nplant) was greater with fertilization at R3 stage compared to the other stage, and N application increased the yield just at this stage and in the Trop condition. The increase in N shoot (not specifically from fertilizer) with the application at R3 appeared to be related to the increased in yield. However, the N from fertilizer found in the plant shoot was about 20% higher when fertilizer was applied at VE compared with R3. Under Subt condition, the FRE averaging 55%. In contrast, the FRE decreased from low to high nitrogen rates (64 to 40%, respectively) when soybean grown under Trop condition. Most N from fertilizer (38%) was found in the grains, followed by the shoot (14.6%) and the root (0.58%). The use of N fertilizer at reproductive growth stages is a better approach to meet soybean N demand through N fertilization. Potential yield gains are more reliable under Trop condition. (AU)

• FAPESP's process: 13/06515-2 - NITROGEN FERTILIZATION EFFICIENCY ON SOIL-SOYBEAN SYSTEM IN TROPICAL AND SUBTROPICAL ENVIRONMENT
• Grantee: Clovis Pierozan Junior
• Support Opportunities: Scholarships in Brazil - Doctorate