Recovery and agronomic efficiency of nitrogen fertilizers alone and combined with leonardite in rice

Abstract

Nitrogen fertilizers applied in rice farming, lost more than half, the efficiency of these depends on multiple factors related to soil, weather conditions and crop management. The objective was to determine the best options for the application of nitrogen fertilizers, pear improve profitability of rice cultivation. lt is hypothesized that efficiency varíes according to the fertilizer source and that the addition of organic compounds to improve the efficiency thereof Fertilizers studied were: Urea, arnrnonium sulfate, ammonium ni trate and controlled release LCI combined formulas (38-0-00-13) + LC2 (+11% S 39-0-0-0), fertilizer were applied alone and combined with leonardite, except for treatments with controlled release fertilizers, it was on a leve! of 160 kg N I ha. The agronomic and performance variables were analyzed with a randomized block design with three replications, the mean comparison was made with the Duncan test P = 0.05. The recovery efficiency ofthe treatment reached LCI (38-0-00-13) + LC2 (+ 11 % S 39-0-0-0) ammonium nitrate in admixture with leonardite reached a higher recovery efficiency when was applied alone economically controlled release treatment LC 1 (38-0-0 + 13% S) had the highest profit.