Greenhouse Plastic Films Capable of Modifying the Spectral Distribution of Solar Radiation

Abstract

The aim of this paper was to investigate the radiometric properties of innovative covering films for protected cultivation capable of modifying the spectral distribution of the transmitted radiation and thus the vegetative activity. Two photoselective films, three photoluminescent films and one low-density polyethylene film were used as greenhouse coverings for cherry trees and peach trees, grown in pots. The photoselective films were characterised by a reduction of the R/FR ratio in comparison to the natural solar radiation. Tree growth parameters, such as the apical shoot of cherry trees and the shoot of peach trees, were monitored. Different responses to vegetative activities were observed under the films, depending on the species, with a higher shoots growth rate in the peach with respect to the cherry. The photoselective film characterised by the lowest R/FR ratio significantly enhanced the growth of cherry and peach trees in comparison to the trees cultivated under the other greenhouse film

Advanced Optical Materials for Sunlight Control in Greenhouses

“…[7] Photoselective films have shown to be able to effect a variety of crops such as delaying the flowering of strawberry plants, [123] and controlling the height (by influencing the red: far red ratio) of poinsettia, [124] antirrhinum, [125,126] chrysanthemum, [126,127] and cherry and peach trees. [128] Many static materials are used to control the color of the light reaching the crops, including colored screens and nets, [8,[129][130][131][132] reflectors, [133,134] photoselective films, [22,121,124,135,136] fluorescent pigments, [137][138][139] doped glass, [140,141] and luminescent solar concentrators (LSC). [23,142] These devices often reduce the total amount of PAR, although fluorescent dyes that absorb UV radiation and shifting this to PAR may theoretically increase the effective irradiance.…”

Effect of modified greenhouse covers on the development of plants of lycopersicon esculentum mill

“…Greenhouse cropping allows the creation of a suitable environment for the proper development of plants, by controlling the atmosphere generated inside, regardless of the geo climatic conditions of the zone and improving crop quality and profitability. A greenhouse performs as a physical barrier that protects crops from adverse weather conditions (rain, hail, frost, wind, and UV radiation, among others) and provides an appropriate microclimate for the optimal development of the plantation [14][15][16]. A greenhouse is actually a structure covered with plastic film between 80 and 200-micron thick, meeting certain physical, mechanical, optical and thermal properties.…”

The Effect of Radiative Cooling on Reducing the Temperature of Greenhouses

“…There were many methods described in literature to regulate the temperature inside the greenhouse, such as ventilation, an evaporative cooling system, and a liquid radiation filter (LRF), etc. [ 1 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 ]. However, these methods may consume plenty of energy.…”

“…We can reduce near-infrared radiation through achieving high reflectance or low transmittance. For covering materials, common plastic films are polyethylene (PE), poly (methyl methacrylate) (PMMA), and ethylene vinyl acetate (EVA) [ 1 , 11 , 15 ], and the chemical substances are mainly divided into organic or inorganic [ 13 , 19 , 20 ]. However, organic substances have poorer dispersing ability, weather resistance, and thermal stability than that of the inorganic substances.…”