S24 - Session P2 - Temperature and short-term waterlogging impact the degradation of plant pigments in kale (Brassica oleracea L.) extracted samples

Authors: Skyler Brazel *, Bikash Adhikari, T. Casey Barickman

Current predictions associated with climate change anticipate greater frequencies of precipitation events, with greater quantities of precipitation. Previous research has demonstrated that waterlogging of plants causes reductions in plant pigments. However, the stability of plant pigments has yet to be quantified. The current study investigated whether waterlogging and different storage temperatures of extracted samples would impact the degradation rate of plant pigments of kale. Carotenoid and chlorophylls were extracted from kale plants that were waterlogged or non-waterlogged, stored in acetone, and sealed in amber vials. Vials were stored at four different temperatures (25, 10, -10, and -80°C) and analyzed 0, 30, 60, 120, and 240 days after initial extraction. After 240 days of storage, all pigments exhibited a treatment by temperature by day interaction. Overall, as storage temperature decreased, the rate of degradation decreased with waterlogged kale plants having a lower concentration of pigments compared to non-waterlogged plants. Additionally, greater variability arose in individual pigment retention like that of chlorophyll B. Chlorophyll B concentrations of waterlogged plants had greater retention at 10°C and 25°C than that of non-waterlogged plants at the same temperatures measured after 30 days of storage. The results of our study display a new challenge that needs to be faced when supplying healthy and nutritious food: abiotic stressors affect the nutritional stability of food over time. Understanding the nutritional stability of foods subjected to abiotic stressors will be essential to improving food nutrition in human diets.