Evapotranspiration and crop coefficients of Moringa oleifera under semi-arid conditions in Pernambuco

Célia S Dos Santos,Abelardo A De A Montenegro,Márcio A L Dos Santos,Elvira M R Pedrosa

doi:10.1590/1807-1929/agriambi.v21n12p840-845

Abstract

ABSTRACT Efficient water use in agriculture is fundamental, especially in semi-arid regions where water scarcity is intense. The aim of this study was to estimate water requirements and crop coefficients in the different phenological stages of Moringa oleifera. The experiment was carried out from February to April 2015 at the Experimental Unit for Reuse and Hydrological Management, located in Mutuca, PE (7º 15’ 18’’ S, 35º 52’’ 40’’ W, 550 m). A lysimeter was used to estimate crop evapotranspiration. Reference evapotranspiration (ETo) was estimated by indirect methods. In the lysimeter, soil salinity and leaf water potential of the crop were monitored. The direct and indirect methods presented an excellent performance compared with the standard grass-lysimeter, especially Hargreaves-Samani, which presented a remarkable result for the study area. Crop coefficients (Kc) ranged from 0.73 to 1.73 in the different phenological stages. Moringa crop evapotranspiration (ETc) exhibited temporal variations, with a cumulative rate of 139.8 mm, for a cumulative reference evapotranspiration of 130.97 mm. Moringa plants showed slight water restriction, at the times of lower solar radiation.

Highlights

Moringa (Moringa oleifera Lam.) is a species native to India with good adaptation to the edaphoclimatic conditions of the semi-arid region of Northeast Brazil (Oliveira et al, 2013)
Agricultural activities consume large volumes of water; efforts with respect to rational and efficient use of this natural resource have been made, through technologies that allow precise measurements of evapotranspiration, such as lysimeters, or through climatological data, which contribute to a good estimate of water demand and adequate irrigation management (Lacerda & Turco, 2015)
Regarding the indices “d” and “c”, which evaluated agreement and performance, respectively, of the ETo values estimated by the proposed methods (Figure 1), all methods evaluated and compared with the standard showed values of 0.99, considered as of good agreement and classified as “excellent” for the performance criterion, for estimates of two days

Summary

Introduction

Moringa (Moringa oleifera Lam.) is a species native to India with good adaptation to the edaphoclimatic conditions of the semi-arid region of Northeast Brazil (Oliveira et al, 2013). This oilseed crop can be exploited under irrigated and rainfed conditions and has great potential due to the multiplicity of uses (Lorenzi & Matos, 2002). Agricultural activities consume large volumes of water; efforts with respect to rational and efficient use of this natural resource have been made, through technologies that allow precise measurements of evapotranspiration, such as lysimeters, or through climatological data, which contribute to a good estimate of water demand and adequate irrigation management (Lacerda & Turco, 2015). Many studies comparing the different ETo determination methods are found in the literature for different regions (Santos et al, 2008; Silva et al, 2014; Tanaka et al, 2016)

Objectives

Methods

Results

Conclusion