Aluminum negative impact on nitrate reductase activity, nitrogen compounds and morphological parameters in sorghum plants

Abstract

Aluminum toxicity represents a limiting factor for yield in crops, and study linked to aluminum impact on nitrate reductase and nitrogen compounds is fundamental to explain decreases in growth and development of sorghum plants. Aim of this study was to investigate (i) aluminum impact in sorghum plants, and to measure (ii) nitrate reductase activity, nitrogen compounds, and morphological parameters. Experimental design was completely randomized with 4 aluminum concentrations (0, 50, 100, and 150 M Al). Parameters measured were leaf area, nitrate reductase activity in leaf and root, proline, amino acids, and total soluble proteins. Significant decreases in nitrate reductase activities were showed in leaf and root tissues. Results linked to total soluble proteins demonstrated that plants treated with aluminum suffered reduction in this parameter promoted by aluminum. This study revealed two relationships between nitrate reductase in leaf and total soluble proteins, as well as between total soluble proteins and shoot dry matter, and also low tolerance of sorghum plants to aluminum.