Fluxos de agua em especie de citro (citrus sinensis L. Osbeck - laranja pera) - Campinas - São Paulo / Water flows in species of citrus (citrus sinensis L. Osbeck - Orange pear) - Campinas - São Paulo - Brazil

AUTOR(ES)
DATA DE PUBLICAÇÃO

2005

RESUMO

The variables ecofisiológicas exercise great influence, not only in the vegetative behavior of the cultivated plants, but, above all in your acting in relation to the productive characteristics. The studies on gas exchange have been enlarging since the decade of eighty, given your importance in tropical cultivations, just as, in citrus varieties. Has been investigating that the stomatal is the principal point of control of the flow of water, being the deficit of pressure water of the air appeared as the motive force for the perspiration, and the amount of water in the soil it is the decisive factor for the provisioning water of the plant. In that way, the efficiency of the use of the water for the culture can be considered as a relationship cost-benefit for the increase of the production of the citrus, with the minimum impact in the reservation water of the ecosystem, have seen that in Brazil, in spite of the incidence of periods of deficits temporary waters in several areas citrícolas, the cultivation prevails without irrigation. Brazil is one of the largest world producers of citric fruits, standing out States: Bahia, Minas Gerais, Rio Grande do Sul, Rio de Janeiro, São Paulo and Sergipe. With plantings above 1.100.000 hectares, the citrus have great commercial importance in Brazil, being São Paulo the largest producing with approximately 70% of the national production. The originating from economical return this product is of great importance for the growth of the agricultural section of the country. Starting from the crop of 1979-1981, the Brazilian citricultura is occupying the first place inside in production of South America. For such, the study was lead in the experimental field of the College of Engenharia Agrícola (FEAGRI) of the State University of Campinas, located in the city of Campinas, enters the geographic coordinates of 22o53?20? of south Latitude and the meridian 47o04?40? of Longitude west of Greenwich. The experiment was led in five plants of citrus of same variety (Citrus sinensis L. Osbeck), accomplishing perspiration measures, conductance stomatal, radiation fotossinteticamente activates, total incident radiation and deficit of pressure of saturated vapor. In the considered period it was observed that the largest average daily rate of the perspiration 4.63 mmol.m-2.s-1 in PL4T2 and the smallest was of 1.53 mmol.m-2.s-1 in PL1EVP1. The best model was that that considered that answer of the perspiration to foliate to be directly associated to the deficit of pressure of saturated vapor

ASSUNTO(S)

plantas - efeito da radiação solar vapor pressure pressão de vapor plants transpiration citros citrus plantas - transpiração plants mathematical models effect of solar radiation on

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