Evapotranspiração e coeficiente de cultivo do feijão-caupi cultivado em solo do cerrado submetido à cobertura morta

Abstract

The determination of water parameters of a crop during its development is essential to maintain yield without wasting water. This study aimed to determine evapotranspiration (ETc) and crop coefficient (Kc) of cowpea crop (Vigna unguiculata L.) cv. Novaera during the various stages of development in soil conditions with and without mulch. The experiment was conducted in Cauamé, campus of the Federal University of Roraima, from April to July 2014, Boa Vista, Roraima state. Evapotranspiration cultivation (ETc) was obtained by drainage lysimeter, while the evapotranspiration reference (ETo) was estimated by Penman-Monteith and Jensen-Haise methods. The results determined that water consumption of cowpea in soil conditions with and without mulch were 311.0 and 260.4 mm, respectively. For Kc's developmental stages, initial (I), growth (II), reproductive (III), and final (IV), Penman-Monteith method showed values of 0.42, 0.82, 1.60, and 0.79 in soil without mulch, and 0.30, 0.73, 1.46, and 0.56 in soil with mulch, although the Jensen-Haise method showed values of 0.38, 0.76, 1.31 and 0.61 in soil with mulch and 0.29, 0.67, 1.19, and 0.42 in soil with mulch.