Estratégias nutricionais para a produção do feijão mungo preto irrigado sob pivô central em solo do cerrado

Abstract

Black mung bean (Vigna radiata (L.) R. Wilczek) shows potential for expansion in irrigated systems of the Brazilian Cerrado, standing out for its ability to establish symbiosis with nitrogen-fixing bacteria. However, strategies integrating nitrogen management and the use of silicon are still little explored for this crop. In this context, the objective was to evaluate the effect of supplying silicon, via stabilized potassium silicate, associated with different nitrogen supply strategies, on the nutritional, physiological, growth, and productive performance of black mung bean. The experiment was conducted in the field, under center pivot irrigation, in a typical eutrophic Yellow Latosol, in the experimental area of the School of Agronomy of the Federal University of Goiás, in a randomized block design in a 3 × 3 factorial scheme, with five replications. The treatments consisted of three foliar spraying (control, potassium chloride, and stabilized potassium silicate) and three nitrogen supply strategies (absence of additional nitrogen, inoculation with Bradyrhizobium sp., and mineral fertilization with urea). Physiological and nutritional variables, nodulation, growth, and yield components were evaluated. The interaction between silicon and nitrogen supply strategies influenced nitrogen content and accumulation, gas exchange, plant growth, and grain yield. Inoculation promoted a greater number and mass of nodules and greater nitrogen accumulation in the plant, while stabilized potassium silicate favored an increase in plant biomass and the weight of one thousand grains. The highest productivity was observed in the combination of stabilized potassium silicate and inoculation. It is concluded that the association between silicon and biological nitrogen fixation represents a promising strategy to improve the physiological and productive performance of black mung bean in irrigated systems in the Cerrado.