Evapotranspiração da cultura da cebola

Abstract

<p><span>A determinação da quantidade de água necessária para as culturas é um dos principais fatores para o correto planejamento, dimensionamento e manejo de qualquer sistema de irrigação. O presente trabalho teve como objetivo, comparar medida da evapotranspiração da cultura (ETc) da cebola com estimativa obtida a partir da evapotranspiração de referência (ETo) determinada por diferentes métodos e Kc proposto na literatura. O experimento foi conduzido no campo experimental do Departamento de Tecnologia e Ciências Sociais da Universidade do Estado da Bahia - UNEB, em Juazeiro, no período de junho a setembro de 2011. As medidas da ETc foram obtidas em evapotranspirômetros e as estimativas, a partir de ETo determinada pelos métodos: Penman-Monteith (padrão FAO), Penman-Monteith modificado por Villa Nova et al. (2004), Hargreaves & Samani, Makkink e Jensen & Haise e Kc proposto por Marouelli et al. (2005), para a cultura da cebola.<strong> </strong>É fundamental a avaliação de métodos de estimativa da evapotranspiração de referência antes de sua aplicação, pois erros consideráveis podem ser cometidos na determinação da quantidade de água a ser aplicada a uma cultura, o que repercutirá certamente, na produtividade.</span></p><p align="center"><strong><em>Evapotranspiration crop onion</em></strong></p><p><strong>Abstract</strong><strong>: </strong>The determination of the amount of water needed for crops is a major factor for the correct planning, sizing and management of any irrigation system. This study aimed to compare measure of crop evapotranspiration (ETc) onion with estimates obtained from the reference evapotranspiration (ETo) determined by different methods and Kc proposed in the literature. The experiment was conducted in the experimental field of the Department of Technology and Social Sciences, University of the State of Bahia, in Juazeiro, from June to September 2011. The ETc measurements were obtained in evapotranspirometers and estimates, from ETo determined by the methods: Penman-Monteith (FAO standard), Penman-Monteith modified by Villa Nova et al. (2004), Hargreaves & Samani, Makkink and Jensen & Haise and Kc proposed by Marouelli et al. (2005), for the cultivation of onion. It is critical to evaluation of reference evapotranspiration estimation methods before their application because considerable mistakes can be made in determining the amount of water to be applied to a culture, which resonate certainly in productivity.</p><p><span><br /></span></p>

Agronomic performance and physicochemical characteristics of onion genotypes under different spacing in the humid Amazonian tropics

“…A peculiar characteristic of the onion is that, once the bulb growth phase begins, the growth of the leaves stops. Therefore, the size of the bulb at harvest is greatly influenced by the size and number of leaves on the plant, and it is important that the stimulation of the photoperiod only occurs after the plant has reached a certain degree of growth so that it is able to produce a large and well-formed (Oliveira et al, 2015). In the experiment there were significant differences for this parameter (p <0.01), the cultivar Vale Ouro IPA 11 with 60.78 g and Mata Hari with 53.90 g, both in the spacing between lines of 40 cm, were the ones that presented the highest ABW.…”