RT Journal Article
SR Electronic
T1 Light and growth form interact to shape stomatal ratio among British angiosperms
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 163873
DO 10.1101/163873
A1 Christopher D. Muir
YR 2017
UL http://biorxiv.org/content/early/2017/07/14/163873.abstract
AB In most plants, stomata are located only on the abaxial leaf surface (hypostomy), but many plants have stomata on both surfaces (amphistomy). High light and herbaceous growth form have been hypothesized to favor amphistomy, but these hypotheses have not been rigourously tested together using phylogenetic comparative methods.I leveraged a large dataset including stomatal ratio, Ellenberg light indicator value, Raunkiær lifeform, and phylogenetic relationships for 372 species of British angiosperms. I used phylogenetic comparative methods to test how light and/or growth form influence stomatal ratio.High light and herbaceous growth form are correlated with amphistomy, as predicted, but they also interact; the effect of light is pronounced in therophytes (annuals) and perennial herbs, but muted in phanerophytes (mostly trees). Interestingly, amphistomy and stomatal density evolve together in response to light, suggesting coordinated selection on this trait combination.I show for the first time that light and growth form interact to shape variation in stomatal ratio; amphistomy is advantageous in high light, but mostly for herbs. These results improve our understanding of the adaptive significance of stomatal ratio as well as its use as functional trait for paleoecology and crop improvement.