Assessing Nitrogen Limitation in Inoculated Soybean in Southern Brazil. Issue 1 (1st November 2019)

• Record Type: Journal Article
• Authors: Ambrosini, Vítor Gabriel; Vieira Fontoura, Sandra Mara; Paulo de Moraes, Renato; Carciochi, Walter; Ciampitti, Ignacio A.; Bayer, Cimélio
• Is Part Of: Agrosystems, geosciences & environment. Volume 2:Issue 1(2019)
• Page Start: 1
• Page End: 6
• Publication Date: 2019-11-01
• Subjects: Agriculture -- Periodicals; Agriculture -- Environmental aspects -- Periodicals; Soil science -- Periodicals; Food science -- Periodicals; Food science; Agriculture; Agriculture -- Environmental aspects; Electronic journals; Periodicals; 630
• DOI: 10.2134/age2019.03.0016
• Languages: English
• ISSNs: 2639-6696

Abstract

Abstract : Core Ideas: Soybean yield did not respond to low starter fertilizer N rates in soils with high organic matter content. Nitrogen limitation tended to be greater in low compared with medium‐high yield levels. Nitrogen limitation is potentially related to lower contribution of N coming from biological nitrogen fixation (BNF) and mineralization. Overcoming potential N limitation in soybean [ Glycine max (L.) Merr.] is a critical factor for sustaining plant nutrient demand and improving productivity. Following this rationale, a set of studies were executed in southern Brazil with the goals of quantifying yield response to early season fertilizer N rates (up to 40 kg ha −1 ), "starter N fertilization, " and to understand if soybean seed yields are limited by N (testing a non‐limiting N scenario) when grown in soils with medium to high organic matter content. The main key outcomes of this research were: (i) starter N fertilization did not increase yields compared with non‐fertilized soybean, potentially highlighting the absence of an early season N limitation; and (ii) N limitation was observed when soybean yields were compared with non‐limiting N scenario and it tended to be greater in low compared with medium‐high yield levels, potentially connected with co‐limitations on both N sources (N2 fixation and mineralization) to satisfy soybean N demand. Producing soybean in a sustainable manner implies focus on production practices to conserve and, potentially, to increase soil organic matter on a long‐term basis. Furthermore, it requires enhancing the biological N2 fixation process for satisfying the large plant N demand for achieving high soybean yields. Future research should be focused on understanding factors governing biological N2 fixation and N mineralization processes in soybean grown in soils with medium‐high organic matter content.