File(s) under permanent embargo
Ancestral stomatal control results in a canalization of fern and lycophyte adaptation to drought
journal contributionposted on 2023-05-17, 20:04 authored by McAdam, SAM, Timothy BrodribbTimothy Brodribb
- Little is known about how a predominantly passive hydraulic stomatal control in ferns and lycophytes might impact water use under stress. Ferns and lycophytes occupy a diverse array of habitats, from deserts to rainforest canopies, raising the question of whether stomatal behaviour is the same under all ecological strategies and imposes ecological or functional constraints on ferns and lycophytes.
- We examined the stomatal response of a diverse sample of fern and lycophyte species to both soil and atmospheric water stress, assessing the foliar level of the hormone abscisic acid (ABA) over drought and recovery and the critical leaf water potential (Ψl) at which photosynthesis in droughted leaves failed to recover.
- The stomata of all ferns and lycophytes showed very predictable responses to soil and atmospheric water deficit via Ψl, while stomatal closure was poorly correlated with changes in ABA. We found that all ferns closed stomata at very low levels of water stress and their survival afterwards was limited only by their capacitance and desiccation tolerance.
- Ferns and lycophytes have constrained stomatal responses to soil and atmospheric water deficit as a consequence of a predominantly passive stomatal regulation. This results in a monotypic strategy in ferns and lycophytes under water stress.
Publication titleNew Phytologist
Department/SchoolSchool of Natural Sciences
PublisherWiley-Blackwell Publishing Ltd.
Place of publicationOxford, UK
Rights statementCopyright 2013 the authors and New Phytologist Trust