Limits to xylem refilling under negative pressure in Laurus nobilis and Acer negundo

The ability of juvenile Laurus nobilis and Acer negundo plants to refill embolized xylem vessels was tested under conditions of soil drought when xylem sap pressure was substantially negative, thus violating the expected condition that pressure must rise to near atmospheric for refilling. Intact potted plants were dried to a stem water potential ( Y W ) corresponding with approximately 80% loss of hydraulic conductivity (PLC) in shoots. Then plants were re-watered and kept at a less negative target Y W for 1‐48 h. The Y Y W was measured continuously with stem psychrometers. Rewatered L. nobilis held at the target Y Y Y W for 1 h showed no evidence for refilling unless Y W was within a few tenths of a MPa of zero. In contrast, re-watered L. nobilis held for 24 and 48 h at water potentials well below zero showed a significant reduction in PLC. The recovery was highly variable, being complete in some stem segments, and scarcely evident in others. Embolism repair was accompanied by a significant but moderate decrease in the osmotic potential ( Yp ) of the bulk xylem sap ( Yp = - - 67 kPa in recov

[1]  Reversing cavitation in tracheids of Pinus sylvestris L. under negative water potentials , 1994 .

[2]  M. Tyree,et al.  A theoretical model of hydraulic conductivity recovery from embolism with comparison to experimental data on Acer saccharum , 1992 .

[3]  M. Gullo,et al.  A method for inducing xylem emboli in situ: experiments with a field‐grown tree , 1992 .

[4]  W. R. N. Edwards,et al.  The refilling of embolized xylem in Pinus sylvestris L. , 1991 .

[5]  J. Grace,et al.  The Limits to Xylem Embolism Recovery in Pinus sylvestris L. , 1992 .

[6]  A. Nardini,et al.  Refilling of embolized vessels in young stems of laurel. Do We need a new paradigm? , 1999, Plant physiology.

[7]  N. Holbrook,et al.  Bordered pit structure and vessel wall surface properties. Implications for embolism repair. , 2000, Plant physiology.

[8]  Maurizio Mencuccini,et al.  Control of stomatal conductance by leaf water potential in Hymenoclea salsola (T. & G.), a desert subshrub , 1998 .

[9]  U. Meeteren,et al.  Fluid ionic composition influences hydraulic conductance of xylem conduits , 2000 .

[10]  M. Mccully,et al.  Daily embolism and refilling of xylem vessels in the roots of field-grown maize. , 1998, The New phytologist.

[11]  H. Cochard,et al.  Cryo-scanning electron microscopy observations of vessel content during transpiration in walnut petioles. Facts or artifacts? , 2000, Plant physiology.

[12]  P. Miller,et al.  WATER RELATIONS OF SELECTED SPECIES OF CHAPARRAL AND COASTAL SAGE COMMUNITIES , 1975 .

[13]  J. Sperry.  Water Transport in Plants under Climatic Stress: Winter xylem embolism and spring recovery in Betula cordifolia, Fagus grandifolia, Abies balsamea and Picea rubens , 1993 .

[14]  N. Holbrook,et al.  Dynamic changes in petiole specific conductivity in red maple (Acer rubrum L.), tulip tree (Liriodendron tulipifera L.) and northern fox grape (Vitis labrusca L.) , 2000 .

[15]  John S. Sperry,et al.  Xylem Embolism in Ring‐Porous, Diffuse‐Porous, and Coniferous Trees of Northern Utah and Interior Alaska , 1994 .

[16]  T. Hinckley,et al.  Daily and seasonal variation in water relations of macchia shrubs and trees in France (Montpellier) and Turkey (Antalya) , 1992 .

[17]  Mccully.  Root xylem embolisms and refilling. Relation To water potentials of soil, roots, and leaves, and osmotic potentials of root xylem Sap , 1999, Plant physiology.

[18]  M. Tyree,et al.  Hydraulic Conductivity Recovery versus Water Pressure in Xylem of Acer saccharum. , 1992, Plant physiology.

[19]  N. Holbrook,et al.  Diurnal variation in xylem hydraulic conductivity in white ash (Fraxinus americana L.), red maple (Acer rubrum L.) and red spruce (Picea rubens Sarg.) , 1998 .

[20]  M. Tyree,et al.  Effect of stem water content on sap flow from dormant maple and butternut stems: induction of sap flow in butternut. , 1992, Plant physiology.

[21]  N. Holbrook,et al.  Embolism repair and xylem tension: Do We need a miracle? , 1999, Plant physiology.

[22]  J. Oertli.  Water Transport in Plants under Climatic Stress: Effect of cavitation on the status of water in plants , 1993 .

[23]  Melvin T. Tyree,et al.  A method for measuring hydraulic conductivity and embolism in xylem , 1988 .

[24]  P. Melcher,et al.  Hydrogel Control of Xylem Hydraulic Resistance in Plants , 2001, Science.

[25]  M. Mccully,et al.  Measurements of the time to refill embolized vessels , 2001 .

[26]  M. Tyree,et al.  Use of positive pressures to establish vulnerability curves : further support for the air-seeding hypothesis and implications for pressure-volume analysis. , 1992, Plant physiology.

[27]  M. Gullo,et al.  Water Transport in Plants under Climatic Stress: Drought resistance strategies and vulnerability to cavitation of some Mediterranean sclerophyllous trees , 1993 .

[28]  J. Sperry,et al.  New evidence for large negative xylem pressures and their measurement by the pressure chamber method , 1996 .

[29]  E. Schulze,et al.  Element concentrations in the xylem sap of Picea abies (L.) Karst. seedlings extracted by various methods under different environmental conditions. , 1994, Tree physiology.

[30]  L. G. Klikoff,et al.  Car6on Dioxide Exchange by Several Streamside and Scrub Oak Community Species of Red Butte Canyon, Utah , 1973 .

[31]  J. Sperry,et al.  Xylem embolism in response to freeze-thaw cycles and water stress in ring-porous, diffuse-porous, and conifer species. , 1992, Plant physiology.

[32]  Hervé Cochard,et al.  A technique for measuring xylem hydraulic conductance under high negative pressures , 2002 .

[33]  J. Sperry,et al.  Cavitation fatigue. Embolism and refilling cycles can weaken the cavitation resistance of xylem. , 2001, Plant physiology.

[34]  J. Sperry,et al.  SEASONAL OCCURRENCE OF XYLEM EMBOLISM IN SUGAR MAPLE (ACER SACCHARUM) , 1988 .

[35]  Melvin T. Tyree,et al.  A new stem hygrometer, corrected for temperature gradients and calibrated against the pressure bomb , 1984 .

[36]  U. Hacke,et al.  Xylem dysfunction during winter and recovery of hydraulic conductivity in diffuse-porous and ring-porous trees , 1996, Oecologia.

[37]  E T Ahrens,et al.  In vivo observation of cavitation and embolism repair using magnetic resonance imaging. , 2001, Plant physiology.

[38]  M. Gullo,et al.  Xylem recovery from cavitation-induced embolism in young plants of Laurus nobilis: a possible mechanism. , 1996, The New phytologist.

[39]  John S. Sperry,et al.  Intra‐ and inter‐plant variation in xylem cavitation in Betula occidentalis , 1994 .

[40]  John S. Boyer,et al.  Measuring the Water Status of Plants and Soils , 1995 .

[41]  M. Tyree,et al.  Detection of Xylem Cavitation in Corn under Field Conditions. , 1986, Plant physiology.

[42]  Nicanor Z. Saliendra,et al.  Influence of leaf water status on stomatal response to humidity, hydraulic conductance, and soil drought in Betula occidentalis , 1995, Planta.