Features of the Lighting Spectrum Influence on the Productivity and Biochemical Composition of Test Fruit and Leaf Vegetable Crops

Abstract

The work is devoted to the study of the photosynthetically active radiation spectral characteristics influence on the productivity and quality of lettuce and dwarf tomato adapted for protected ground. High pressure sodium lamps and LEDs emitting yellow light, pink light and close to sunlight spectrum were used as test options for plant illumination. Vegetable crops were grown under controlled conditions of intensive lightculture by thin-layer panoponics; the same irradiance was achieved in all variants. Using a light source simulating sunlight with a photosynthetic photon flux of 76 μmol m^–2 s^–1 in the 400–500 nm range, 130 μmol m^–2 s^–1 in 500–600 nm and 133 μmol m^–2 s^–1 at 600–700 nm made it possible to obtain an increase in productivity by 10% for lettuce and by 23% for tomato, and also led to an increase in the content of magnesium and iron in lettuce leaves and a higher content of carbohydrates, vitamin C, crude ash in tomato fruits compared to standard sodium lamps.