Evapotranspiration and crop coefficients of corn in monoculture and intercropped with jack bean

Mário S P De Araújo,Daniel F De Carvalho,Fernando H A Ferreira,Vinícius R Pereira,Elias F De Sousa

doi:10.1590/1807-1929/agriambi.v21n1p27-31

Abstract

ABSTRACT This study was carried out to determine the evapotranspiration (ETc) and crop coefficients (Kc) for four stages of “Caatingueiro” corn under the climate condition of Seropédica, RJ, Brazil, using weighing lysimeters. The field trial occurred in 2015, from March 18 to June 25, in two areas cultivated with “Caatingueiro’ corn intercropped with jack bean and in monoculture. The reference evapotranspiration (ETo) was estimated by the FAO-56 Penman-Monteith model and the Kc values were determined by the ratio between ETc and ETo. The Kc values obtained for the intercropping and monoculture systems, were respectively: 0.78 (I); 1.01 (II); 1.10 (III) and 1.01 (IV), and 0.62 (I); 0.92 (II); 1.27 (III) and 0.81 (IV), and they were different from the values presented by FAO.

Highlights

Corn is one of the main cereals produced in the world and Brazil is the third largest producer
Corn germination occurred on the 4th day after sowing (DAS), while thinning and replanting were performed on the 15th day after emergence (DAE), respecting the desired limit of 5 plants m-1 (Correa et al, 2014), which corresponded to a density of 50,000 plants per hectare
The corn cultivation cycle lasted for 99 days, and the intercropped system showed a total water consumption of 314.9 mm (3.18 mm d-1), while corn in monoculture showed 292.1 mm (2.92 mm d-1)

Summary

Introduction

Corn is one of the main cereals produced in the world and Brazil is the third largest producer. The intercropped cultivation can improve grain yield through the more efficient use of nutrients, water and radiation (Lithourgidis et al, 2011), besides reducing the incidence of pests and diseases, soil degradation, environmental deterioration (Brooker et al, 2015) and the risks of production losses (Heredia et al, 2003). Working with ‘mucuna-cinza’ (Mucuna cinereum), Souza et al (2012) observed greater water consumption in the intercropping in relation to corn monoculture, corroborating with Coll et al (2012), but not affecting water use efficiency. The present study aimed to determine the water consumption and crop coefficients (Kc) of corn (‘BRS Caatingueiro’) in monoculture and intercropped with jack bean (Canavalia eusiformis)

Material and Methods

Results and Discussion

Conclusions

Literature Cited