PRODUÇÃO DE ALFACE HIDROPÔNICA E MICROCLIMA DE AMBIENTE PROTEGIDO SOB MALHAS TERMO-REFLETORAS

Abstract

The thermo-reflective and black screens was used for shading for plants and they has private properties that improve the microclimate conditions, it was aimed to evaluate the growth and yields in hydroponic lettuce production (Lactuca sativa L, cv. Olinda), under effect of the thermo-reflective with different percentages of attenuation of the solar radiation. The treatments were and thermo black screens 50% with four different percentages of attenuation of the solar radiation, being meshes 40, 50, 60 and 70%. It was observed significant differences in function of the treatments for all the analyzed characteristics number of leaf, diameter of stem, fresh and dry matter biomass, leaf area and distances of internodes. The meshes thermo-reflective 40 and 50%, it had provided better development for lettuce, in relation to expression of the economical characteristics, being suitable to supply shading in greenhouse conditions at Northeastern semi-arid areas. However, it's improved the most control of the solar radiation, temperature and relative humidity, with micro weather conditions the best for growth and yields of Lettuce.