A 2023 study by Hamid Reza Soufi and his team suggests that light-emitting diode (LED) technology could significantly enhance plant growth and metabolic activities. In addition, the study offers valuable insights for developing nutrient solutions and LED spectrum management strategies, particularly in hydroponic systems.
The researchers investigated the impact of different light spectra: red (656 nm), blue (450 nm), red/blue (3:1), and white (peak at 449 nm) on two lettuce cultivars, Lollo Rossa and Lollo Bionda. These cultivars were grown under varying methods of nutrient solution replacement in a hydroponic system.
Results showed that complete replacement and EC-based replacement of nutrient solution under red/blue LED and red LED light treatments increased the content of proline and soluble sugars. This was accompanied by an increase in the activity of antioxidant enzymes (CAT, GPX, and SOD) in both cultivars.
The Lollo Rosa cultivar saw a notable boost in soluble protein content and antioxidant activity under the plant-needs-based replacement method when exposed to red/blue and monochromatic red light. In addition, an increase in flavonoid content was also observed in the Lollo Rosa variety treated with a combination of red and blue light under the EC-based method.
The red/blue light showed the most significant effect on anthocyanin content, expression of UFGT, CHS, and Rubisco small subunit genes, and the net photosynthetic rate.
The findings of this study offer promising strategies for improved plant growth and metabolism in hydroponic systems, mainly through effective nutrient solutions and LED spectrum management. Additionally, these strategies could help mitigate environmental concerns by reducing water and nutrient waste.
While these findings represent a significant step forward in our understanding of how LED light spectra impact plant growth, the researchers recommend further investigation to refine these techniques and explore their applicability to other plant species and growth systems.
Photo by Petr Magera on Unsplash
