Contribution of nitrogen derived from mineral supplementation for soybean seedlings

Abstract

Seeds can absorb N from mineral supplementation, thus stimulating seedling development in soybeans (Glycine max (L.) Merrill). This study aimed to evaluate the contribution to soybean seedlings of N derived from mineral supplementation in seeds with different nutritional contents. Seeds of the cultivar BMX Potência RR received mineral supplementation enriched with 2.5% excess 15N. The treatments were performed in seeds in two lots, one with high and one with low nutritional content. At 2, 6 and 10 days after sowing on paper towels, the seedlings were collected and separated into cotyledons, roots and shoots. Dry matter production, root length and root volume were assessed. Total N and 15N values were analyzed in the seedling organ tissues. The seeds from the lot with lower nutritional content absorbed more N from the mineral supplement, which was accumulated in the cotyledons and redistributed to the root systems and cotyledons. At 10 days after sowing, most of the N in the organs of soybean seedlings was derived from the seed reserves, regardless of nutritional content. Thus, application of N through mineral supplementation is of low importance for the development and nutrition of seedlings.

Side dressing nitrogen fertilization in soybean in association with inoculation

“…For this, investigations on mineral nitrogen in soybean seek to better understand the dynamics between BNF and additional supplementation with nitrogen. Among the various factors investigated, we found studies that associate nitrogen doses with sowing density (FERREIRA et al, 2016;WERNER et al, 2016); supplementary mineral nitrogen with its effects on oil and/or protein contents in grains (HAMAGUCHI et al, 2020;MOREIRA et al, 2017;PRUSIŃSKI, BATURO-CIEŚNIEWSKA, BOROWSKA, 2020;SZPUNAR-KROK et al, 2021); nitrogen supply with seed quality (ZUFFO et al, 2021); as well as those that investigate the dynamics of nitrogen absorption in the initial stages of soybean, in which the BNF is not yet meeting the requirements of the crop (CONCEIÇÃO et al, 2018); in addition to studies on the effects of fixed nitrogen in the subsequent crop (GOSS et al, 2002;ZUFFO et al, 2022); and studies on foliar nitrogen and their effects on carbon and oxidative metabolism (RODRIGUES et al, 2021). Bahry et al (2014) pointed out that, in some edaphoclimatic conditions, nitrogen from BNF is not enough to meet the requirements of the crop and its limitation may compromise the final productivity, evidencing that the application of nitrogen in the reproductive phase of soybean positively influences some yield components.…”