Response of brachiaria grass to selenium forms applied in a tropical soil

Abstract

In Brazil the total area of native and cultivated pasture used for livestock is around 180 million hectares, and selenium (Se) is absent from mineral fertilizer formulas. Nutritional supplementation of this element takes place along with provision of mineral salts in the form of sodium selenite. In the present work, the effects of adding selenate and selenite on Se biofortification, antioxidant activity and anatomy alterations in Brachiaria brizantha were evaluated. The experiments were disposed in a completely randomized design in a 6 × 2 factorial scheme, by means of five levels of Se (0; 0.5; 1.0; 3.0 and 6.0 mg/kg) applied along with grass plant fertilizer, and two Se forms (sodium selenate and sodium selenite), with six replications. The results of the present study suggest that, in tropical soil conditions, the application of Se as selenate at low doses is more appropriate for B. brizantha biofortification than Se as selenite, because it favors a greater shoot Se levels, better activation of the antioxidant system and reduces on lipid peroxidation. Finally, with an increase of Se rates, cellular modifications were observed in internal structures of roots in B. brizantha, with aerenchyma appearing.

Genotypic Variation and Biofortification with Selenium in Brazilian Wheat Cultivars

“…To determine Se content in the roots, shoots, and grains of each sample, we first digested the material with concentrated HNO 3 (Sigma‐Aldrich) in a CEM microwave oven (Mars Model 5, CEM Corporation). Selenium concentration of the digestate was performed by graphite furnace atomic absorption spectrometry (PerkinElmer AAnalyst 800), according to a methodology described by Ramos et al (2012). The detection limit of the method was 18 μg kg −1 .…”

Effects of selenium (Se) application and arbuscular mycorrhizal (AMF) inoculation on soybean (Glycine max) and forage grass (Urochloa decumbens) development in oxisol

“…The agricultural intervention that enhances the Se levels in edible parts of crop plants has been defined as biofortification (Garg et al, 2018), and this can be used as fortification and as supplementary strategy to enhance human and animal nutrition (Reis et al, 2009;Ebert and Jacob, 2007). There are many studies focused on the Se biofortification in different crops (Ramos et al, 2012;Ekanayake et al, 2015;Malagoni et al, 2015;Reis et al, 2018), but few of them has been carried out to investigate the influence of arbuscular mycorrhizal fungi (AMF) on the uptake of this element by plants (Durán et al, 2013;Goicoechea et al, 2015). This aspect has been over looked in tropical soils and crops, where AMF has strong effect on plant growth and nutrition.…”

Anatomia e morfometria de raízes e folhas de Urochloa brizantha cv. Marandu em diferentes estádios de acometimento da síndrome da morte das pastagens

“…Ramos et al (2012), relataram o surgimento de aerênquima em raízes de U. brizantha abastecidas com altos níveis de selênio. Pereira et al (2008), afirmaram que o córtex é a região mais sensível da raiz a alterações do ambiente, corroborando com os resultados aqui citados.…”