Functional diversity of photobiological traits within the genus Symbiodinium appears to be governed by the interaction of cell size with cladal designation. Issue 2 (28th May 2015)

• Record Type: Journal Article
• Authors: Suggett, David J.; Goyen, Samantha; Evenhuis, Chris; Szabó, Milán; Pettay, D. Tye; Warner, Mark E.; Ralph, Peter J.
• Is Part Of: New phytologist. Volume 208:Issue 2(2015:Nov. 01)
• Page Start: 370
• Page End: 381
• Publication Date: 2015-05-28
• Subjects: Botany -- Periodicals; 580
• DOI: 10.1111/nph.13483
• Languages: English
• ISSNs: 0028-646X

Abstract

<abstract abstract-type="main" id="nph13483-abs-0001"> <title>Summary</title> <p> <list id="nph13483-list-0001" list-type="bullet"> <list-item> <p>Dinoflagellates of the genus <italic>Symbiodinium</italic> express broad diversity in both genetic identity (phylogeny) and photosynthetic function to presumably optimize ecological success across extreme light environments; however, whether differences in the primary photobiological characteristics that govern photosynthetic optimization are ultimately a function of phylogeny is entirely unresolved.</p> </list-item> <list-item> <p>We applied a novel fast repetition rate fluorometry approach to screen genetically distinct <italic>Symbiodinium</italic> types (<italic>n </italic>=<italic> </italic>18) spanning five clades (A–D, F) for potential phylogenetic trends in factors modulating light absorption (effective cross‐section, reaction center content) and utilization (photochemical vs dynamic nonphotochemical quenching; [1 – <italic>C</italic>] vs [1 – <italic>Q</italic>]) by photosystem II (PSII).</p> </list-item> <list-item> <p>The variability of PSII light absorption was independent of phylogenetic designation, but closely correlated with cell size across types, whereas PSII light utilization intriguingly followed one of three characteristic patterns: (1) similar reliance on [1 – <italic>C</italic>] and [1 – <italic>Q</italic>] or (2) preferential reliance on [1 – <italic>C</italic>] (mostly A, B types) vs (3) preferential reliance on [1 – <italic>Q</italic>] (mostly C, D, F types), and thus generally consistent with cladal designation.</p> </list-item> <list-item> <p>Our functional trait‐based approach shows, for the first time, how <italic>Symbiodinium</italic> photosynthetic function is governed by the interplay between phylogenetically dependent and independent traits, and is potentially a means to reconcile complex biogeographic patterns of <italic>Symbiodinium</italic> phylogenetic diversity in nature.</p> </list-item> </list> </p> </abstract>