Production efficiency of ‘BRS Pujante’ cowpea using single and dual Kc for irrigation

Ericlis D Da S Nunes,Marcos E B Brito,Edjane G Rodrigues,José S C De Sousa,William C Da Silva,José J F Cordeiro Junior

doi:10.1590/1807-1929/agriambi.v25n9p648-654

Abstract

ABSTRACT The objective of this study was to evaluate the production efficiency of cowpea (Vigna unguiculata L. Walp.), ‘BRS Pujante’, from the weather-based irrigation scheduling using single and dual Kc. The study was carried out in randomized block design with two treatments (single and dual crop coefficient) and 12 replicates. Chlorophyll a, chlorophyll b and total chlorophyll contents, soil matric tension, number of pods per plant, number of grains per pod, average 100 grains weight, total grain yield and water use efficiency were evaluated. Scheduling with single and dual Kc did not interfere with chlorophyll pigments. Single Kc promoted tension values closer to zero during cowpea development stages III and IV. Significant difference was observed only for the average 100 grains weight, with higher value for dual Kc. The irrigation depth with the single Kc was 360.8 mm and there was a 9.3% water saving when compared to dual Kc, without significantly affecting cowpea yield. It is possible to use irrigation scheduling with single Kc for the stages I and II and dual Kc for the stages III and IV of cowpea, ‘BRS Pujante’.

Highlights

Beans are one of the main foods consumed by the human population, playing a relevant role in the diet, mainly as a source of proteins, carbohydrates and minerals (Azevedo et al, 2015; Gomes et al, 2017)
By analyzing the gross irrigation depths (GID) applied at stages II, III and IV of cowpea cultivation (Figure 2A), it can be observed that at stage II, the irrigation depth defined by single Kc increased gradually, as for dual Kc since the beginning of this stage, which promoted greater accumulation of the water depth applied in this stage, especially for the dual Kc
The scheduling in the beginning of stage III using single and dual Kc had constant values of irrigation depth, and the dual Kc management led to a lower applied depth, as in stage IV, when it was possible to notice that there is a reduction in the depth used in both managements

Summary

Introduction

Beans are one of the main foods consumed by the human population, playing a relevant role in the diet, mainly as a source of proteins, carbohydrates and minerals (Azevedo et al, 2015; Gomes et al, 2017). According to Borém & Carneiro (2013), the average yield of the crop is from 700 to 1,000 kg ha-1, but its potential is greater than 2,000 kg ha-1 under adequate water conditions (Ramos et al, 2012; Oliveira et al, 2015; Moreira et al, 2016; Gonçalves et al, 2017). The crop coefficient (Kc) in turn can be either single or dual. Single Kc is indicated for practical purposes of irrigation with intervals ranging from one week to longer. Dual Kc, on the other hand, is recommended for frequent irrigations and in scientific research (Allen et al, 1998; Silva et al, 2012)

Objectives

Methods

Results

Conclusion