Research conducted by Signify (Euronext: LIGHT), the global leader in lighting, in conjunction with Wageningen University & Research and Nunhems, has shown that using far-red light can increase tomato yield by nearly 20%, depending on the variety. Furthermore, the study demonstrated that this increase is achieved when far-red light is utilized throughout the entire photoperiod alongside the standard PAR (Photosynthetically Active Radiation) light.
The study’s main objective was to optimize the use of LED lights, particularly in the growth and development of different crops. Philips Horticulture LED Solutions, a division of Signify, collaborates with partners to research and define optimal light recipes and photoperiods (lighting duration). These efforts recently culminated in new insights specific to tomato cultivation.
Each color within a light spectrum can affect plant development uniquely, and the effect can vary depending on the time of day. Consequently, the study aimed to ascertain the most effective timing for applying far-red light to crops. The research findings affirmed that the most productive results were achieved when far-red light was used during the photoperiod.
Despite these promising results, the optimal use of far-red light is not yet fully understood. “We now have a deeper understanding of how far-red light impacts plants during different times of the day. The next step is to focus on balancing far-red and PAR light to find the ideal equilibrium between crop growth optimization and energy efficiency,” said Erik Stappers, Plant Specialist at Philips Horticulture LED Solutions.
During the 20-week study, all far-red treatments increased sink strength, which enhances the flow of sugars to the fruits. However, this only led to a significant increase in harvest when far-red light was applied throughout the entire photoperiod, which in this study was 16 hours a day. It was observed that the best results indicated a 16% increase in yield, although variations between tomato varieties make the results somewhat uncertain for growers.
The study concluded that there is no specific time of day when plants are more responsive to far-red light. The use of far-red light, however, does require more energy than PAR light, leading to increased energy consumption when used throughout the entire photoperiod.
The researchers are now focusing on balancing the benefits of increased yield and the additional energy consumption that far-red light necessitates. “We continue to refine the ideal light recipe for tomatoes. Besides increased yield, we anticipate improved quality and taste in the future,” stated Elena Jiménez, Plant Pathology Researcher at Wageningen University.
Philips Horticulture LED Solutions, Nunhems, and Wageningen University & Research have been collaborating for about seven years to investigate the optimal light recipe for tomatoes, considering factors such as energy consumption, light spectrum, increased yield, and crop uniformity.
Image provided by Philips Horticulture LED