EFFECT OF ADDITIONAL LOW INTENSITY LUMINESCENCE RADIATION 625 nm ON PLANT GROWTH AND PHOTOSYNTHESIS

(Licopersicon esculentum Mill.) and cabbage (Brassica oleracea L. var. Cymosa) plants were grown in a glass greenhouse under natural radiation in summer. A half of pots with plants were placed under an ordinary (control) and the other part under the "Redlight " (experimental variant) polyethylene films, both 100/lm thick. The Redlight film had the same transmittance but transformed 3.5 % of ultraviolet light falling on a plant into fluorescent radiation with a main maximum of 625 nm. Plants grown under modified solar radiation exhibited high intensity of photosynthesis at light saturation, a shift of saturation region to the higher level of radiation, as well as high efficiency of photosynthesis under low light intensity. An appreciable increase in the CO2 assimilation rate and biological productivity under modified light irradiation of plants allows recommending the method of additional plant irradiation under controlled conditions. Under natural irradiation of plants this can be achieved by the use of Redlight film. Key words: light-transforming film; solar radiation; controlled environment; photosynthetic activity;. biological productivit