Biomass, efficiency of nitrogen conversion and nitrogen recovery in millet cultivars under nitrogen fertilization

Abstract

The objective of this study was to evaluate the production of green mass (GM), dry mass (DM), nitrogen contained (NC), bromatological composition, apparent nitrogen conversion efficiency (NCE), and apparent nitrogen recovery (ANR) of millet cultivars (ADR-500, ADR 7020 and LABH 70732) that received different doses of nitrogen (N) (0, 50, 100, 200 kg.ha-1). The experimental design was randomized blocks in a 3x4 factorial scheme (three cultivars and four N rates) with four replications. About biomass, only GM showed an interaction between N and millet cultivars. The DM production showed difference only between N doses. The NCE and ANR differed between N doses with decreasing mean values, due to the increase of nitrogen fertilization. The best conversion efficiency was 54.06 kg DM/kg N applied. The best rate of recovery of N occurred with the application of 50 kg N.ha-1. The values of NC varied in the fertilized plots. NCE and ANR differed between millet cultivars. The bromatological composition variables did not differ as a function of the N doses evaluated. In the conditions of the present study, nitrogen fertilization did not influence the production and bromatological composition of millet cultivars. The three cultivars present satisfactory characteristics for use in ruminant feed.