138344 - Xylem cavitation isolates leaky flowers during water stress in pyrethrum - accepted.pdf (6.92 MB)
Xylem cavitation isolates leaky flowers during water stress in pyrethrum
journal contribution
posted on 2023-05-20, 13:24 authored by Ibrahim BourbiaIbrahim Bourbia, Madeline Carins-Murphy, Alistair GracieAlistair Gracie, Timothy BrodribbTimothy Brodribb- Flowers underpin plant evolution, genetic legacy and global food supply. They are exposed to similar evaporative conditions as leaves, yet floral physiology is a product of different selective forces. We used Tanacetum cinerariifolium , a perennial daisy, to examine the response of flowers to whole‐plant water stress, determining if flowers constitute a liability during drought, and how this species has adapted to minimize risk associated with reproduction.
- We determined the relative transpiration cost of flowers and leaves and confirmed that flowers in this species are xylem‐hydrated. The relative water stress tolerance of leaves and flowers then was compared using xylem vulnerability measurements linked with observed tissue damage during an acute drought treatment.
- Flowers were a major source of water loss during drought but the xylem supplying them was much more vulnerable to cavitation than leaves. This xylem vulnerability segmentation was confirmed by observations that most flowers died whereas leaves were minimally affected during drought.
- Early cavitation and hydraulic isolation of flowers during drought benefits the plant by slowing the dehydration of perennial vegetative organs and delaying systemic xylem damage. Our results highlight the need to understand flower xylem vulnerability as a means of predicting plant reproductive failure under future drought.
History
Publication title
New PhytologistVolume
227Pagination
146-155ISSN
0028-646XDepartment/School
School of Natural SciencesPublisher
Blackwell Publishing LtdPlace of publication
9600 Garsington Rd, Oxford, England, Oxon, Ox4 2DgRights statement
Copyright 2020 The Authors. New Phytologist Copyright 2020 New Phytologist TrustRepository Status
- Restricted
