الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The wide distribution of protected cultivation in Europe and other Mediterranean countries has increased the production and marketing of a large variety of greenhouse covering materials. The covering material is a basic thctor influencing the energy consumption, the yield and the general economics of the greenhouse (Papadakis et aL, 2000). One of the most important developments in commercial protected cropping is the introduction of photoselective plastic films. These include novel plastic films with increased light transmission, growth control properties, heat control properties, and ultraviolet transparent or blocking properties (Ashkenazi, 1996).
The new system of plant production performed in this study could be the suitable alternative solution to the traditional covers from agronomic context point of view. This achieved by the manipulation of ambient light in protected crop system and getting higher quality crop with lower costs. This work rely on the technological sophistication of the films BPI provide which in Turn depend on film designed on the base of solid biological understanding of how light transmission relate to commercially desirable end-points.
One of the most exciting applications of photoselective plastic films appears to be in the area of heat control. A number of photoselective plastic films that have thermic properties now exist. Thermic films have the property of transmitting short infrared wavelengths, while substantially blocking the transmission of long infrared wavelengths, thus creating a higher degree of “Greenhouse Effect” with a consequent increase in night time temperature (Yilmazer et aL, 1991).
Two greenhouse experiments were conducted during the winter
seasons of 2009 and 2010 to evaluate the effect of some thermic plastic