Research of the LED emission mode impact on the productivity and physicochemical marks of Japanese cabbage in the tiered hydroponic module conditions

FSBSI “Federal Scientific Agroengineering Center VIM”, Moscow, Russia

^* Corresponding author: knyazewa.inna@yandex.ru

Abstract

Growth rates, plant biomass and the concentration of beneficial compounds largely depend on the quality and intensity of illumination. Plants of the ‘Mizuna Red’ variety were grown using a low-volume technology in a regulated agroecosystem of a tiered hydroponic module produced by VIM (Russia). The plants were illuminated by specially designed LED lamps manufactured by VIM (Russia) with a dy-namically controlled spectral composition in 4 channels. For experimental researches, the design of the lighting system included several modes of emission: continuous, pulsed and scanning with a radiation intensity of 15000 lux and a total PAR of 321 µmol m^-2s^-1: blue – 97 µmol m^-2s^-a; green – 84 µmol m^-2s^-1; red – 122 µmol m^-2s^-1; far red – 18 µmol m^-2s^-1 (Proportions B: G: R ~ 30:26:44). The aim of the study was to assess the effect of different modes of emission on productivity, physi-cochemical indicators and to develop technological methods for obtaining highquality commercial products of Japanese cabbage variety 'Mizuna Red' grown in a longline hydroponic module. The use of a pulsed emission mode made it possible to increase the photosynthetic activity of ‘Mizuna Red’ plants, which eventually influenced the growth of the aboveground mass and its quality indicators with a strong correlation between these indicators. The concentration of photosynthetic pigments was dependent on the emission mode.