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Solar radiation under greenhouse has always been of primary concern in greenhouse farmers of Korea and northern Europe in winter season. Light transmission through the double layer film was the highest in the heat and fluorescent film, following fluorescent film. While the light transmittance of heat and fluorescent film was the greatest, 86.4%, that of antifog film was the lowest, 84% on solar radiation. When films were excited at 265 ㎚, both heat and fluorescent film and fluorescent film were significantly increased at 610-635 ㎚ emission area as compared with ethylene vinyl acetate (EVA) of antifog film. The minimum temperature of double layer greenhouse in the heat and fluorescent greenhouse was about 2℃ higher than in the EVA greenhouse, while the maximum temperature of heat and fluorescent greenhouse was significantly higher than that of EVA. Antifog greenhouse appeared lower humidity, but condensation water amount in the inner film surface was the most compared with the others. Chlorophyll content was the highest in the heat and fluorescent greenhouse, the lowest in the EVA and antifog greenhouses. Expecially, the difference of chlorophyll content between heat and fluorescent and EVA film showed larger on hot pepper than tomato and strawberry. The yields of hot pepper were observed about 1.3 ㎏ per plant under heat and fluorescent film and about 1.0 ㎏ per plant under EVA. Heat and fluorescent greenhouse-grown plants were obtained the greatest production at early harvest, and EVA or fluorescent greenhouse-grown plants increased yield at late harvest. However, as results, heat and fluorescent greenhouse produced the most yield at each plant compared with the others. Higher temperature under the heat and fluorescent greenhouse, due to increase of light transmittance and heat accumulation, induced significantly higher growth and yield for vegetables. We suggest that heat and fluorescent film may be more efficient than the other films for vegetables required for high temperature in winter greenhouse cropping.
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