Data_Sheet_1_The Role of Sustained Photoprotective Non-photochemical Quenching in Low Temperature and High Light Acclimation in the Bloom-Forming Arctic Diatom Thalassiosira gravida.docx

• Main Authors: Thomas Lacour, Jade Larivière, Joannie Ferland, Flavienne Bruyant, Johann Lavaud, Marcel Babin
• Format: Dataset
• Language: unknown
• Published: 2018
• Subjects: Oceanography; Marine Biology; Marine Geoscience; Biological Oceanography; Chemical Oceanography; Physical Oceanography; Marine Engineering; Arctic diatom; photosynthesis; sustained NPQ; irradiance; temperature; Arctic
• Online Access: https://doi.org/10.3389/fmars.2018.00354.s001; https://figshare.com/articles/Data_Sheet_1_The_Role_of_Sustained_Photoprotective_Non-photochemical_Quenching_in_Low_Temperature_and_High_Light_Acclimation_in_the_Bloom-Forming_Arctic_Diatom_Thalassiosira_gravida_docx/7234661

Thalassiosira gravida is a major Arctic diatom responsible for the under-ice spring bloom. We investigated T. gravida physiological plasticity growing it at two temperatures (0 and 5°C) and under different light intensities typically found in its natural environment. T. gravida showed remarkable thermal- and photo-acclimatory plasticity including: low light saturation parameter for growth (K E ) and photosynthesis (E K ), low μ max but relatively high Chl a/C, low C/N, and decreasing light-saturated carbon fixation rate (PmC) with increasing growth irradiance. T. gravida also showed remarkable photoprotective features, namely a strong sustained non-photochemical quenching (NPQs, hour kinetics relaxation) supported by a high amount of xanthophyll cycle pigments. T. gravida growth remained possible under a wide range of irradiances but photosynthetic plasticity was higher at moderately low light (up to ~50 μmol photons m −2 s −1 ), nevertheless corresponding to the mean in situ conditions under which it predominates, i.e., underneath the spring thin-ice punctuated with melting ponds. The potential role of NPQs in the photophysiological plasticity of T. gravida is discussed.