LIGHT AS AN ENVIRONMENTAL FACTOR FOR PLANTS
Of all the climatic factors involved in plant development; CO2, temperature, humidity, etc., light is one of the most important. It is an essential factor for the plant to be able to carry out photosynthesis and on which it depends directly in order to synthesise organic matter from mineral substances. Light provides the energy necessary for the plant to carry out photosynthesis, which produces the organic matter for its growth and development.
Photosynthetic activity and its efficiency increases with light, temperature and CO2, so if you want to achieve a good development of the crop and an increase in productivity, you must ensure good and correct lighting. The higher the lighting, the more efficient the photosynthesis and the faster the plant can develop. However, as the light intensity increases, the speed of photosynthesis reaches a limit. This maximum point is called the “light saturation point”, at which point the speed of the physico-chemical process of photosynthesis becomes flat.
The amount of light received by the plant will depend on two main factors; the intensity and the number of hours of daily exposure. The changes in light received by the plants is called photoperiod, and the exposure time or hours of light needed for the crop to develop and reach flowering varies according to the species.
All plants need light, and below a certain threshold, very few of them are able to survive. But both too much and too Little light have harmful consequences for plants. Plants that receive insufficient light levels have less vegetative growth, less flowering, become weaker and produce smaller leaves. On the other hand, plants that receive too much light can produce what is called chlorosis (Chlorosis is the yellowing of leaf tissue caused by a lack of chlorophyll).
This vitally important parameter can be monitored inside a greenhouse by means of a climate programmer that controls shading screens (in case the light intensity is high), blackout (if darkness is to be feigned, in short-day crops when they are in long daylight) and assimilation lights (applied when there is not enough light for good crop growth).