Growth and Biosynthesis of Phenolic Compounds of Canola (Brassica napus L.) to Different Ultraviolet (UV)-B Wavelengths in a Plant Factory with Artificial Light

Abstract

The application of ultraviolet-B (UV-B) irradiation to supplement visible light as an elicitor to increase bioactive compounds under controlled conditions is increasing. This study aimed to evaluate the effects of UV-B dose and wavelength region (280–300 and 300–320 nm) on the morphological, physiological, and biochemical responses of canola plants (Brassica napus L.). Canola plants (17 days after sowing) were subjected to various UV-B intensities (i.e., 0.3, 0.6, and 0.9 W m−2) and were divided into cut and non-cut treatments for each UV treatment. Plant growth parameters exhibited different trends based on the treated UV irradiation intensity. Plant growth gradually decreased as the UV irradiation intensity and exposure time increased. Despite the same UV irradiation intensity, plant response varied significantly depending on the presence or absence of a short-wavelength cut filter (<300 nm). Canola plants suffered more leaf damage in nonfilter treatments containing shorter wavelengths (280–300 nm). UV treatment effectively activates the expression of secondary metabolite biosynthetic genes, differing depending on the UV irradiation intensity. Our results suggest that both UV irradiation intensity and wavelength should be considered when enhancing antioxidant phytochemicals without inhibiting plant growth in a plant factory with artificial light.

The Multifaceted Responses of Plants to Visible and Ultraviolet Radiation

“…Different Ultraviolet (UV)-B Wavelengths in a Plant Factory with Artificial Light [9] This study sheds light on the effects of different UV-B doses on several morphological, physiological, and biochemical parameters of canola (Brassica napus L.) plants. The authors tested both short (280-300 nm) and long (300-320 nm) wavelengths.…”

Molecular Shield for Protection of Buckwheat Plants from UV-B Radiation

“…In plants, the growth is decreased with the intensity of UV irradiation. UV treatment effectively activates the expressions of secondary-metabolite biosynthetic genes, and also in Linum , canola, soybeans, and other plants, depending on the UV-irradiation intensity and time of impact [ 47 , 48 , 49 ]. UV-B exposure may increase the nutritional and nutraceutical quality of crop plants [ 47 ].…”

“…UV treatment effectively activates the expressions of secondary-metabolite biosynthetic genes, and also in Linum , canola, soybeans, and other plants, depending on the UV-irradiation intensity and time of impact [ 47 , 48 , 49 ]. UV-B exposure may increase the nutritional and nutraceutical quality of crop plants [ 47 ]. Melatonin was reported as an enhancer of the synthesis of flavonoids under exposure to UV-B radiation by promoting the gene expressions for enzymes involved to flavonoid synthesis [ 49 ].…”

Urban Flora Riches: Unraveling Metabolic Variation Along Altitudinal Gradients in Two Spontaneous Plant Species

“…The UV-B-absorbing compounds that plants accumulate in response to UV radiation are mainly phenolic compounds, particularly flavonoids and hydroxycinnamate esters [ 17 ]. UV-absorbing compounds play a key role in DNA protection [ 18 ] and the regulation of processes such as the inhibition of stem and leaf elongation, cotyledon expansion, and stomatal opening [ 19 ]. Among the protective roles, these compounds interfere with plant–insect relationships [ 20 ].…”