N-15-Fertilizer Recovery in Maize as an Additional Strategy for Understanding Nitrogen Fertilization Management with Blends of Controlled-Release and Conventional Urea

Author(s)

Garcia, Pedro Lopes ^[1] ; Sermarini, Renata Alcarde ^[2] ; Ana Filho, Carlos Roberto de Sant ^[3] ; Bendassolli, Jose Albertino ^[1] ; Boschiero, Beatriz Nastaro ^[1] ; Trivelin, Paulo Cesar Ocheuze ^[1]

Affiliation

^[1] Univ Sao Paulo, Ctr Nucl Energy Agr CENA, Stable Isotopes Lab, BR-13416000 Piracicaba, SP - Brazil

^[2] Univ Sao Paulo, Luiz de Queiroz Coll Agr ESALQ, Exact Sci Dept, BR-13418900 Piracicaba, SP - Brazil

^[3] Compass Minerals Plant Nutr, Innovat Ctr, BR-13495000 Iracemapolis, SP - Brazil

• Document type: Journal article
• Source: AGRONOMY-BASEL; v. 10, n. 12 DEC 2020.
• Web of Science Citations: 0

Abstract

A single application of polymer-sulfur coated urea (PSCU) and conventional urea (U) is expected to ensure nitrogen (N) throughout the maize (Zea mays L.) growth cycle being U the likely main N-fertilizer supplier at the beginning and PSCU during the maize growth cycle. This research aimed to evaluate N fertilization management (split, incorporated, and broadcast application) and fertilizer blends (30%PSCU + 70%U and 70%PSCU + 30%U) on volatilization of ammonia (AV) and soil N mineral content (NM); plant N uptake (NU) and N-15-fertilizer recovery (NR); and yield (GY). Field experiments were conducted for two growing seasons (2017-2018 and 2019-2020) in Rhodic Eutrustox soil. U was treated with NBPT (N-(n-butyl) thiophosphoric triamide). N rate was 180 kg ha(-1). AV reached 12% of the applied N (broadcast-applied 70%PSCU + 30%U, 2017-2018). The 30%PSCU + 70%U application resulted in higher NM at 40-60 cm depth in vegetative and reproductive stages in both seasons. The 70%PSCU + 30%U application resulted in the highest GY in 2017-2018, and the N treatments did not affect GY in 2019-2020. NR was 3% on average at vegetative leaf stage 4 (V4), and PSCU, the main N-fertilizer supplier applying 70%PSCU + 30%U. After V4, the main N-fertilizer supplier is PSCU for 70%PSCU + 30%U and U for 30%PSCU + 70%U application. These blends (incorporated, broadcast, and split application) can ensure N during the maize growth cycle, with NR of 72.5% at maturity (R6) being 47.9% in the grain. (AU)

• FAPESP's process: 17/25813-5 - Nitrogen (15N) use efficiency for fertilization managements of maize and common bean using mixtures of polymer sulfur coated urea and conventional urea
• Grantee: Pedro Lopes Garcia
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 17/24516-7 - Special nitrogen fertilization managements in sugarcane, corn and common bean crops aiming to increase N use efficiency (NUE) and agricultural yield
• Grantee: Paulo Cesar Ocheuze Trivelin
• Support Opportunities: Regular Research Grants