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  • How and why do species break a developmental trade‐off? Elucidating the association of trichomes and stomata across species
Title: How and why do species break a developmental trade‐off? Elucidating the association of trichomes and stomata across species
Abstract PremisePrevious studies have suggested a trade‐off between trichome density (Dt) and stomatal density (Ds) due to shared cell precursors. We clarified how, when, and why this developmental trade‐off may be overcome across species. MethodsWe derived equations to determine the developmental basis forDtandDsin trichome and stomatal indices (itandis) and the sizes of epidermal pavement cells (e), trichome bases (t), and stomata (s) and quantified the importance of these determinants ofDtandDsfor 78 California species. We compiled 17 previous studies ofDt–Dsrelationships to determine the commonness ofDt–Dsassociations. We modeled the consequences of differentDt–Dsassociations for plant carbon balance. ResultsOur analyses showed that higherDtwas determined by higheritand lowere, and higherDsby higherisand lowere. Across California species, positiveDt–Dscoordination arose due toit–iscoordination and impacts of the variation ine. ADt–Dstrade‐off was found in only 30% of studies. Heuristic modeling showed that species sets would have the highest carbon balance with a positive or negative relationship or decoupling ofDtandDs, depending on environmental conditions. ConclusionsShared precursor cells of trichomes and stomata do not limit higher numbers of both cell types or drive a generalDt–Dstrade‐off across species. This developmental flexibility across diverse species enables differentDt–Dsassociations according to environmental pressures. Developmental trait analysis can clarify how contrasting trait associations would arise within and across species.  more » « less
Award ID(s):
1951244 2017949 2307341
PAR ID:
10536483
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
American Journal of Botany
Date Published:
Journal Name:
American Journal of Botany
Volume:
111
Issue:
5
ISSN:
0002-9122
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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