Intracanopy Lighting in Phytocenoses and Photobiological Efficiency of Radiation in Photoculture Conditions

Abstract

The review is devoted to the study of the internal radiation regime in the canopies cultivated under controlled environmental conditions. The expediency of using canopies as an object of research for evaluating the photobiological efficiency of radiation in light culture conditions is justified. The appropriateness of light measurements in multi-tiered canopies is shown, taking into account the role of leaves of different tiers in the formation of an economically useful crop. The main requirements for light devices for their use in measuring artificial radiation in light culture conditions are considered, and a brief analysis of the existing instrument base for performing these studies is given. A number of examples show the complexity and ambiguity of the internal structure of the light field that is forming within canopies in light culture conditions. Conceptual approaches to the choice of spectral and energy characteristics of artificial irradiation for plant light culture are proposed and justified. The necessity of taking into account the light conditions of leaves of different tiers when choosing the spectral and energy characteristics of light sources for the cultivation of multi-tiered canopies is justified. Techniques, methods, and light sources used for additional intracanopy lighting are analysed. The efficiency of using side illumination of plant canopies and conditions for its implementation are considered. The advantages of the volume distribution of canopies on the most common multi-tiered lighting installations are discussed. Based on the presented material, we consider ways to improve methodological approaches for evaluating the photobiological effectiveness of artificial radiation in light culture conditions for canopies of cultivated plants, taking into account the features of their architectonics and internal radiation regime.