Premium
Turgor and osmotic relations of the desert shrub Larrea tridentata
Author(s) -
MEINZER F. C.,
RUNDEL P. W.,
SHARIFI M. R.,
NILSEN E. T.
Publication year - 1986
Publication title -
plant, cell and environment
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.646
H-Index - 200
eISSN - 1365-3040
pISSN - 0140-7791
DOI - 10.1111/j.1365-3040.1986.tb01762.x
Subject(s) - turgor pressure , larrea , osmotic pressure , apoplast , chemistry , water content , dilution , botany , horticulture , osmometer , shrub , cell wall , biology , chromatography , thermodynamics , biochemistry , physics , geotechnical engineering , engineering
Leaf water relations characteristics of creosote bush, Larrea tridentata , were studied in view of previous reports that its leaves commonly experience zero or negative turgor under dry conditions. Leaf turgor loss point () was determined by a pressure‐volume method for samples subjected to a hydration procedure and for untreated samples. Hydration caused to increase by as much as 3 M Pa. Hydration of samples also caused changes in other leaf water relations characteristics such as symplastic solute content, tissue elasticity and symplasmic water fraction, but total leaf solute content was unchanged. Comparison of our field plant water potential data with values of obtained by the two methods resulted in predictions of turgor loss during part or all of a diurnal cycle based on hydrated samples, and turgor maintenance (at least 0.3 MPa) based on untreated samples. Pooled data for obtained from both partially hydrated and untreated samples showed that L. tridentata maintains fairly constant levels of turgor over a wide range of leaf water potential. Dilution of cell contents by apoplastic water introduced significant errors in psychrometric determinations of osmotic potential in both frozen and thawed leaf tissue and expressed cell sap. Use of these values of osmotic potential resulted in predictions of zero turgor at all plant water potentials measured in the field.