Efeito da cobertura de polietileno difusor de luz em ambiente protegido cultivado com pimentão (Capsicum annuum L.)
Carregando...
Data
2002-03
Autores
Sousa, Jorge Washington de [UNESP]
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Estadual Paulista (Unesp)
Resumo
Esta pesquisa foi conduzida em ambiente protegido na área experimental do Departamento de Recursos Naturais - Setor de Ciências Ambientais da Faculdade de Ciências Agronômicas - UNESP, Campus de Botucatu, SP, durante o período de 21/04 a 02/11/2000, para avaliar o efeito do polietileno difusor de luz com 150μm de espessura (P150d), sobre os componentes da radiação solar, balanços de ondas curtas e longas, saldo de radiação, temperatura e fluxo de calor no solo, temperatura e umidade relativa do ar, indicadores de crescimento e produção. Os resultados foram comparados com aqueles obtidos utilizando polietileno de 120 μm de espessura (P120), cujo ensaio foi conduzido entre 21/04 a 03/11/1999, ambos utilizados como cobertura do ambiente protegido cultivado com pimentão híbrido Elisa. O índice de produtividade obtido para o ambiente protegido com cobertura de P150d foi cerca de 50% maior do que o observado para o P120. As coberturas de P150d e P120 proporcionaram respectivamente, acréscimos de 26,82% e 16,71% na fração difusa, comprovando um maior efeito difusor do P150d ao longo do ciclo da cultura de pimentão. O índice do saldo de radiação obtido para o P150d foi maior do que o determinado para o P120, devido ao maior índice do balanço de ondas curtas do P150d, uma vez que os dois polietilenos avaliados apresentaram valores iguais para o índice do balanço de ondas longas. O índice do coeficiente de reflexão determinado para o ambiente protegido com cobertura de P150d, foi menor do que o observado para o P120, o que está associado ao maior índice de fração difusa do P150, em relação ao P120.
This experiment has been carried out under sheltered environment condition in the experimental area of the Natural Resource Department – Environmental Science Section of the Agricultural Science College – UNESP, Campus of Botucatu City, São Paulo State, from April 21st to November 2nd 2000. The objective was to assess the effect of a light diffuser polyethylene, 150 μm thickness, on solar radiation components, long and shortwave balance, net radiation, temperature and flow of heat in the soil, air temperature and relative humidity, as well as growth and yield indexes; compared to a 120 μm (P 120) transparent polyethylene. The latter assay was held from April 21st to November 3rd 1999. Both coverings were used when Elisa hybrid green pepper has been grown. The yield index for sheltered environmental condition with P 150d covering was about 50 % higher than that for P 120 P 150d and P 120 coverings have brought 26.82 % and 16.71 % increases, respectively to the diffuse fraction, confirming the higher diffuser effect of P 150d throughout the green pepper cycle. The index of net-radiation obtained for P 150d was higher than that for P 120, due to the higher index of P 150 d short-wave balance, since the two evaluated polyethylene coverings have shown the same values for the long-wave balance index. The reflexion coefficient index determined for P 150d sheltered environment was lower than that for P 120, which is related to the higher diffuse fraction index of P 150 compared to P 120.
This experiment has been carried out under sheltered environment condition in the experimental area of the Natural Resource Department – Environmental Science Section of the Agricultural Science College – UNESP, Campus of Botucatu City, São Paulo State, from April 21st to November 2nd 2000. The objective was to assess the effect of a light diffuser polyethylene, 150 μm thickness, on solar radiation components, long and shortwave balance, net radiation, temperature and flow of heat in the soil, air temperature and relative humidity, as well as growth and yield indexes; compared to a 120 μm (P 120) transparent polyethylene. The latter assay was held from April 21st to November 3rd 1999. Both coverings were used when Elisa hybrid green pepper has been grown. The yield index for sheltered environmental condition with P 150d covering was about 50 % higher than that for P 120 P 150d and P 120 coverings have brought 26.82 % and 16.71 % increases, respectively to the diffuse fraction, confirming the higher diffuser effect of P 150d throughout the green pepper cycle. The index of net-radiation obtained for P 150d was higher than that for P 120, due to the higher index of P 150 d short-wave balance, since the two evaluated polyethylene coverings have shown the same values for the long-wave balance index. The reflexion coefficient index determined for P 150d sheltered environment was lower than that for P 120, which is related to the higher diffuse fraction index of P 150 compared to P 120.
Descrição
Palavras-chave
Estufa (Plantas), Polietileno, Difusão, Pimentão
Como citar
SOUSA, Jorge Washington de. Efeito da cobertura de polietileno difusor de luz em ambiente protegido cultivado com pimentão (Capsicum annuum L.). 2002. x, 113 f. Tese (doutorado) - Universidade Estadual Paulista, Faculdade de Ciências Agronômicas, 2002.