The LED phyto lighting for improving the environmental friendliness of growing and productivity of lettuce varieties with red and green leaves

Abstract

The intensively developing area of modern phytophysiology is the ecological plants physiology, which important section is the ecology of photosynthesis, by which we understand the intensity and photosynthesis productivity dependence on environmental factors, primarily on optical radiation. The urgent problem of growing plants under artificial conditions is to increase energy efficiency, reduce energy intensity and degree of environmental impact. Using LED irradiators with the function of controlling the spectral composition and optical radiation power, it is possible to increase photosynthesis efficiency and vegetable crop productivity in greenhouses. The comparative study of the effect of sodium lamp radiation and LED irradiators with different spectral composition on the growth and productivity lettuce varieties with red leaves (Anthony, Lolo-Rossa) and with green leaves (Levistro, Lifli), was conducted. The research results showed the different susceptibility of lettuce varieties to the spectral composition of radiation. For the Anthony, Levistro and Lolo-Rossa lettuce varieties, LED radiation application provided the positive effect on plant productivity (8-20%) compared to sodium lamps, and simultaneous reduced in energy consumption of the irradiation system by 40 - 50%. Diodes emission increase in the blue region of the spectrum had a significant positive effect on the synthesis of anthocyanins in the culture of lettuce varieties with red-leaves, compared to sodium lamps. For these varieties, a variable irradiation regime is necessary with a change in the spectrum and increase in the proportion of blue radiation towards the end of growth.

In-door germination and seedling growth of green and red lettuce under LED-light spectrum and subsequent effect on baby leaf lettuce

“…However, Lin et al (2013) and Proshkin et al (2020) did not find significant differences in pigment contents (CHL a, b, and CAR) regardless of the light spectrum. On the other hand, Proshkin et al (2020) indicated that under low light conditions in a greenhouse and a minor blue light fraction, red lettuce leaves tend to remain green as ANT accumulation is lower. Other studies showed that a combination of red and blue or red, blue, and green LED lights induced ANTs contents (Stutte et al, 2009).…”

“…A combination of red and blue LEDs improved CHL content in lettuce (Lee et al, 2016;Choong et al, 2018) and red light alone (Son and Oh, 2013). However, Lin et al (2013) and Proshkin et al (2020) did not find significant differences in pigment contents (CHL a, b, and CAR) regardless of the light spectrum. On the other hand, Proshkin et al (2020) indicated that under low light conditions in a greenhouse and a minor blue light fraction, red lettuce leaves tend to remain green as ANT accumulation is lower.…”

“…In contrast, others mentioned that blue light alone was sufficient to induce ANTs synthesis (Petrella et al, 2016). Literature results showed the dissimilar susceptibility of lettuce types to the spectral composition of light (Lee et al, 2017;Proshkin et al, 2020).…”

Energy­Saving Lighting of Agricultural Premises and its Parameters Calculation

“…Диапазон длин волн излучения светодиодов в красной области спектра составляет 620-680 нм, в оранжевой -610-620 нм, в желтой -585-595 нм, в зеленой -520-535 нм, в голубой -465-475 нм, в синей -450-465 нм и в ультрафиолетовой 370-400 нм (Айзенберг Ю.Ф., 2006). Изменяя ток для разных светодиодов, можно получать различные по составу и интенсивности спектры излучения и таким образом подбирать спектр светильника в зависимости от конкретного этапа развития растения [14][15][16].…”