Growth of bromeliads in greenhouses with different heights and levels of shading. / Desenvolvimento de bromélias em ambientes protegidos com diferentes alturas e níveis de sombreamento.

AUTOR(ES)
DATA DE PUBLICAÇÃO

2002

RESUMO

The objective of this research was to evaluate the effect of different greenhouses heights and levels of shading on the growth of Aechmea fasciata and Guzmania lingulata (Bromeliaceae). The experiment was done from march 26 th of 2001 to april third of 2002, in two greenhouses, built in east-west orientation, at the experimental area of Nucleos of Environment Research – NUPEA, Rural Engineering Department, "Luiz de Queiroz" College of Agriculture, University of São Paulo, Piracicaba, Brazil. Greenhouses measured: 6.4m in width, 17.5m in length and heights of 3.0m and 3.5m. They were covered with 150m thick low density polyethylene (PEBD). Black polypropylene cloth providing shading of 18%, 40%, 60%, and 80% was used. The plants used in the experiment were obtained through micropropagation and transplanted to plastic pots at approximately 90 days after ex vitro culture. The air temperature, the relative humidity, the black globe temperature, the radiant thermal load, and light intensity were evaluated inside the greenhouses. These evaluations were carried out through the direct reading from the following instruments: psycrometers, black globe thermometer, anemometer and digital luximeter. Air temperature, relative humidity and global solar radiation were also obtained through sensors connected to an automatic meteorological station. The development of the plants under different levels of shading and different heights was evaluated according to the number of leaves, height of plants, width of leaves, and the diameter of the rosette. Under the conditions used for the experiment, it can be concluded that the 3.5m high greenhouse showed lower air relative humidity when compared to the 3.0m high greenhouse. Plants of A. fasciata growing under different levels of shading had a better development under 40% cloths, while G. lingulata showed a more vigorous grouth under 60% and 80% of shading.

ASSUNTO(S)

sombreamento estufa shading bromeliads greenhouse bromélia

ACESSO AO ARTIGO

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