Document Type : Original Article

Author

• Mohammad Adibian

Saravan Higher Education Complex - Faculty of Agriculture - member of the faculty of Horticulture Department

Abstract

Supplemental lighting improves growth and yield of greenhouse vegetables such as sweet pepper, cucumber and tomato in all-year round. In the last decade, light emitting diodes (LED) have attracted a lot of attention as a suitable alternative to many other types of supplementary light sources. In general, LED lamps have advantages over existing common lamps, including: higher lifespan, higher light efficiency, more photosynthetically active radiation, special light spectrums, more precise control over wavelengths and light intensity, as well as production lower heat that allows LEDs to be placed near the plant or used in warm ambient conditions. Different spectrums of light cause different processes of plant growth. Therefore, the optimal light spectrum for the physiological processes and growth of different plants may be different. For high-hanging fruiting vegetables, such as tomatoes, sweet peppers and cucumbers, in the early stages of plant growth, it is very important to optimize the light spectrum to increase canopy growth. Once the plants reach full canopy, the focus should be on optimizing vertical light distribution to increase fruit growth that occurs in the middle and bottom canopy. This review clearly shows that, depending on the type of plant, optimal vertical light regimes can be developed to raise plant growth as well as fruit yield and quality in greenhouse vegetable production throughout the year.

Keywords

• Supplemental lighting
• Greenhouse vegetables
• LED lamps

Main Subjects

• olericulture