Effect of far-red light on biomass accumulation, plant morphology, and phytonutrient composition of ruby streaks mustard at microgreen, baby leaf, and flowering stages

Authors: TENG, ZI - University Of Maryland; Luo, Yaguang - Sunny; Sun, Jianghao; Pearlstein, Daniel; OEHLER, MADISON - Oak Ridge Institute For Science And Education (ORISE); FITZWATER, JAMES - Oak Ridge Institute For Science And Education (ORISE); Zhou, Bin; HUSSAN, MUHAMMAD - Oak Ridge Institute For Science And Education (ORISE); Chang, Christine; Chen, Pei; WANG, QIN - University Of Maryland; Fonseca, Jorge

Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/7/2024
Publication Date: 4/8/2024
Citation: Teng, Z., Luo, Y., Sun, J., Pearlstein, D.J., Oehler, M., Fitzwater, J.D., Zhou, B., Hussan, M.A., Chang, C.Y., Chen, P., Wang, Q., Fonseca, J.M. 2024. Effect of far-red light on biomass accumulation, plant morphology, and phytonutrient composition of ruby streaks mustard at microgreen, baby leaf, and flowering stages. Journal of Agricultural and Food Chemistry. 72(17):9587–9598. https://doi.org/10.1021/acs.jafc.3c06834.
DOI: https://doi.org/10.1021/acs.jafc.3c06834

Interpretive Summary: Controlled environment agriculture (CEA) has many potential social and environmental benefits. Taking advantage of CEA’s unprecedented opportunities for targeted improvements in food quality and nutrition by modulation of growth lights, scientists at USDA’s Beltsville Agricultural Research Center comprehensively investigated the effects of far-red light supplementation on the growth rate, yield, and nutritional profile of Ruby Streaks mustard at microgreen, baby leaf, and flowering stages. They report that far-red light applied alone or in combination with white light both significantly increased the yield of harvestable material and accelerated flower development. They also revealed an unusually high concentration of natural occurring health-promoting glucosinolate in the edible flowers of mustard, which can enhance the marketability of edible flower products. Results are also more broadly applicable to benefit CEA growers in developing lighting recipes to maximize yield and nutrition of fresh produce.

Technical Abstract: Far-red (FR) photons influence plant development significantly through shade avoidance response and photosynthetic efficiency enhancement, but there is limited data on how different FR treatments influence the growth and nutrition of vegetables at different growth stages in controlled environment agriculture. This study seeks a comprehensive investigation into the impact of FR on the yield, morphology, and phytonutrients of ruby streaks mustard (RS) at microgreen, baby leaf, and flowering stages. Treatments included white light at a photoperiod of 16 h and daily light integral (DLI) of 11.7 mol/m2/day (WH, control), white with FR at daytime with DLI and eDLI (extended DLI) of 11.9 and 22.0 mol/m2/day respectively, white at daytime followed by FR at nighttime (similar DLI as previous), and enhanced white (WE) at DLI of 22.2 mol/m2/day. Results showed that WE significantly increased the dry weight of RS microgreens compared to the control and increased the dry and fresh weight of baby leaves more remarkably than FR. On the other hand, FR led to significant morphological change during vegetative growth and accelerated the emergence of leaves, flowers, and seed pods more dramatically than WE. Regarding phytonutrients, FR decreased the total glucosinolate and anthocyanin contents in microgreens and baby leaves, whereas WE increased those contents in baby leaves; neither treatment affected the high glucosinolate content of RS flowers. Finally, light treatments had a more remarkable impact on the metabolomic profiles of baby leaves than microgreens and flowers. This study illustrates the complex impact of FR on RS and provides valuable information for selecting optimal lighting conditions in controlled environment agriculture.