Teores de nitrogênio em folhas de feijão Mungo (Vigna Radiata (L.) Wilczek) sob doses de nitrogênio e níveis de irrigação

Abstract

Mung bean is consumed in the form of bean sprouts, but it is not widespread in Brazil in relation to the pinto bean and black bean. The objective of this work was to determine the concentration of leaf nitrogen of the cultivar "Crystal" of mung bean, under different irrigation levels, based on the moisture of the field capacity (CC), and application of nitrogen in the form of urea 30 kg.ha-1. The experiment was conducted in 10-liter pots in the nursery of the Federal University of Mato Grosso - Sinop Campus, from December 12, 2017 to January 20, 2018. The experimental design was a complete randomized complete block (DBC) with four replicates, in a 2x5 factorial scheme. The first factor with two levels was the application of nitrogen in the form of urea during planting at 30 kg.ha-1. The second factor: five levels of water irrigation based on the humidity of the field capacity, 25%, 50%, 70%, 100% and 150% of the CC, with a three day irrigation shift, totaling 40 plots. At the flowering (R5), at 39 days after sowing (DAS) the foliar nitrogen contents by the Kjeldahl method were evaluated. It was observed that with nitrogen fertilization the irrigation increased the growth of the plants and consequently reduced, by dilution, the contents of nitrogen in the foliar tissues. When N fertilization is not done, there is an increase in leaf nitrogen levels for all levels of irrigation.