Modern controlled environment agriculture (CEA) systems allow for the precise manipulation of environmental parameters such light intensity, quality, and mean daily temperature (MDT). This allows for use of end-of-production (EOP) cooling, light intensity, or quality strategies to improve crop quality parameters such as foliage color, mineral nutrients, or phenolic compound synthesis. The objective of Expt. 1 was to produce red leaf lettuce under the environmental conditions that Tarr et al. (2023) reported to maximize yield and quantify the influence of providing 150 μmol∙m‒2 ∙s ‒1 of EOP sole-source lighting providing a light ratio (%) of either 100:00 blue:red (B:R), 75:25 B:R, or 50:50 B:R during the final 6-8 days of production on anthocyanin, nutrition, coloration, and yield of red leaf lettuce (Latuca sativa) ‘Barlach’, ‘Rouxai’, and ‘Thurinus’. Anthocyanin concentration decreased similarly across treatments for each cultivar. In Expt. 2 we exposed red leaf lettuce to EOP treatment consisting of 150 μmol∙m‒2 ∙s ‒1 of 75:25 B:R light and decreased the MDT to either 8, 14, or 20 °C during the final 6-8 days of production. EOP cooling of 8 or 14 °C increased anthocyanin concentration of each cultivar, however decreased fresh mass. In Expt. 3 we grew beet ‘Bulls Blood’ (Beta vulgaris), mustard ‘Miz America’ (Brassica juncea), pac choi ‘Red Pac’ (Brasica rapa var chinensis), cabbage ‘Red Jewel’ (Brassica oleracea), and daikon radish ‘Shunkyo’ (Raphanus sativus) microgreens at a MDT of 20 °C and light intensity of 150 μmol·m‒2 ·s‒1 then exposed them to EOP temperatures of 8, 14 or 20 °C for the final 3 days of production. Coloration of red species and shelf life of ‘Bulls Blood’, ‘Miz America’, and ‘Shunkyo’ improved when exposed to 8 °C.
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