Red light optimized physiological traits and enhanced the growth of ramie (Boehmeria nivea L.)

Abstract

Light is an important variable affecting the plant growth. In present study, the effects of different color light-emitting diodes (mixed colors, red, blue, and orange light) on plant growth, gas exchange, and oxidative stress were investigated in Boehmeria nivea L., by means of measuring growth, photosynthesis, chlorophyll (Chl) content, reactive oxygen species (ROS), and activity of antioxidant enzymes under controlled conditions. Comparing to the mixed colors light, red light significantly increased shoot and leaf biomass, plant height, number of leaves per plant, and stem diameter by increasing the Chl content and therefore promoting the highest photosynthetic capacity. This might partially be explained by the decrease of malondialdehyde and proline contents as well as the activities of superoxide dismutase and peroxidase under red light, to keep a better internal environment of the cell. However, blue and orange light decreased plant growth, and increased the activities of antioxidant enzymes which suggest an environmental stress on plants. These results suggest that red light can enhance B. nivea growth by activating photosynthesis and reducing ROS accumulation.

Application of Light-Emitting Diodes for Improving the Nutritional Quality and Bioactive Compound Levels of Some Crops and Medicinal Plants

“…For example, irradiation with blue and red LED combinations resulted in enhanced biomass during the in vitro culture of Achillea millefolium [ 115 ], Densribium [ 1 ], blueberries [ 114 ], sugarcane [ 110 , 116 ], and chrysanthemum [ 26 ]. In addition to biomass, chlorophyll content was increased in different plant species cultured under LED irradiation [ 24 , 42 , 117 , 118 , 119 ]. In similar studies, increased total carotenoid level was reported in shoot cultures irradiated with different LEDs [ 119 , 120 , 121 ].…”

Light spectrum modifies the drought-induced changes of glutathione and free amino acid levels in wheat

“…Similarly to the spectrum-dependent differences in the amount of the non-enzymatic antioxidant, GSH under various spectral conditions in wheat seedlings, the activity of antioxidants enzymes was also affected by light spectrum indicating their coordinated regulation. Thus, the activities of superoxide dismutase and peroxidase, which are also involved in the control of H 2 O 2 levels as the GSH, decreased in red light and increased in blue and orange lights in ramie (Rehman et al 2020). Blue light also increased the antioxidant capacity in Rehmannia glutinosa (Manivannan et al 2015) and the total antioxidant content in lettuce (Johkan et al 2010) which can be explained by its inducing effect on the intracellular ROS as observed in human epithelial cells (Lockwood et al 2005).…”

“…Blue light was the most effective in the induction of Pro accumulation, since the Pro concentrations were 2-3-fold greater in blue light in the two genotypes compared to pink and far-red light. The Pro content was also greater in blue light then in red one in ramie and rapeseed cultivated under optimal growth conditions (Mh et al 2019;Rehman et al 2020). Blue light (but not red or green) also increased the Pro level in tomato which change was accompanied by its greater tolerance to biotic stress (gray mold disease) (Hee- Sun Kook 2013).…”

Protagonist of Mineral Nutrients in Drought Stress Tolerance of Field Crops

“…When plants are subjected to prolonged drought, it impairs activity of different cell metabolic contents like NADPH. Zinc application inhibits photooxidative damage, reduces ROS generation, and promoting osmolytes concentration like SOD [74,[142][143][144][145].…”