Effect of Variation in Temperature and Light Duration on Morpho-physiology and Phytochemical Content in Sprouts and Microgreens of Common Buckwheat (Fagopyrum esculentum Moench).

Abstract

Common buckwheat (Fagopyrum esculentum Moench) is a gluten-free underutilized pseudocereal with excellent therapeutic and nutraceutical potential. Sprouts and microgreens produced from this plant species can be consumed regularly owing to a rich nutritional profile that can be improved by regulating the abiotic factors during their growth. Therefore, this study explores the responses of common buckwheat sprouts and microgreens in terms of growth and phytochemicals accumulation under temperature (16, and 25 ºC) and photoperiodic (16/8 h and 20/4 h, light/dark intervals) variations. Some analyses were also performed at 4 and 8 ºC. The findings highlight the beneficial effects of mild stress induced by extended photoperiod and moderate temperature like enhanced yield and phytochemical content. Extending the photoperiodic duration from 16/8 h to 20/4 h significantly triggered the biosynthesis of pigments such as carotenoids and chlorophyll in 12-day-old microgreen leaves. Likewise, a moderate temperature i.e., 16 ºC was proved more effective in inducing the accumulation of secondary metabolites including phenolics and flavonoids. However, extreme cold conditions hindered the sprouting and growth rate underscoring common buckwheat sensitivity to low temperature. These findings are crucial for refining the production strategies, ensuring the nutritional values, and optimizing the potential of common buckwheat sprouts and microgreens as "superfoods".