Xylem function and growth rate interact to determine recovery rates after exposure to extreme water deficit
Article first published online: 28 JUL 2010
© The Authors (2010). Journal compilation © New Phytologist Trust (2010)
Special Issue: Featured papers on ‘Pollinator-mediated selection and floral evolution’
Volume 188, Issue 2, pages 533–542, October 2010
How to Cite
Brodribb, T. J., Bowman, D. J. M. S., Nichols, S., Delzon, S. and Burlett, R. (2010), Xylem function and growth rate interact to determine recovery rates after exposure to extreme water deficit. New Phytologist, 188: 533–542. doi: 10.1111/j.1469-8137.2010.03393.x
- Issue published online: 28 JUL 2010
- Article first published online: 28 JUL 2010
- Received: 7 May 2010, Accepted: 4 June 2010
- •Motivated by the urgent need to understand how water stress-induced embolism limits the survival and recovery of plants during drought, the linkage between water-stress tolerance and xylem cavitation resistance was examined in one of the world’s most drought resistant conifer genera, Callitris.
- •Four species were subjected to drought treatments of −5, −8 and −10 MPa for a period of 3–4 wk, after which plants were rewatered. Transpiration, basal growth and leaf water potential were monitored during and after drought.
- •Lethal water potential was correlated with the tension producing a 50% loss of stem hydraulic conductivity. The most resilient species suffered minimal embolism and recovered gas exchange within days of rewatering from −10 MPa, while the most sensitive species suffered major embolism and recovered very slowly. The rate of repair of water transport in the latter case was equal to the rate of basal area growth, indicating xylem reiteration as the primary means of hydraulic repair.
- •The survival of, and recovery from, water stress in Callitris are accurately predicted by the physiology of the stem water-transport system. As the only apparent means of xylem repair after embolism, basal area growth is a critical part of this equation.