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Version 3.24
Publication Type J
Authors Donovan, LA; Linton, MJ; Richards, JH
Author Full Name Donovan, LA; Linton, MJ; Richards, JH
Title Predawn plant water potential does not necessarily equilibrate with soil water potential under well-watered conditions
Language English
Document Type Article
Author Keywords apoplastic solutes; desert shrubs; chaparral shrubs; halophytes; leaf water potential
Abstract Predawn leaf water potential (Psi (w)) and xylem pressure potential (Psi (p)) are expected to be in equilibrium with the soil water potential (soil Psi (w)) around roots of well-watered plants. We surveyed 21 plant species (desert, chaparral, and coastal salt marsh species, as well as two temperate tree and two crop species) for departures from this expectation and for two potential mechanisms explaining the departures. We measured soil Psi (w), leaf Psi (w), and xylem Psi (p) in the glasshouse under well-watered conditions that eliminated soil moisture heterogeneity and ensured good soil-root hydraulic continuity. Most species failed to equilibrate fully with soil Psi (w), depending on whether leaf Psi (w) or xylem Psi (p) was used as the measure of predawn plant water potential. The contribution of nighttime transpiration to predawn disequilibrium was assessed by comparing plants with bagged canopies (enclosed overnight in plastic bags to eliminate transpiration) to plants with unbagged canopies. Nighttime transpiration significantly reduced predawn xylem Psi (p) for 16 of 21 species and the magnitude of this contribution to predawn disequilibrium was large (0.50-0.87 MPa) in four woody species: Atriplex confertifolia, Batis maritima, Larrea tridentata, and Sarcobatus vermiculatus. The contribution of nighttime transpiration to predawn disequilibrium was not more prevalent in mesic compared with xeric or desert phreatophytic compared with non-phreatophytic species. Even with bagging that eliminated nighttime transpiration, plants did not necessarily equilibrate with soil Psi (w). Plant xylem Psi (p) or leaf Psi (w) were significantly more negative than soil Psi (w) for 15 of 15 species where soil Psi (w) was measured. Predawn disequilibrium based on leaf Psi (w) was of large magnitude (0.50-2.34 MPa) for seven of those 15 species, predominately halophytes and Larrea tridentata. A portion of the discrepancy between leaf and soil Psi (w) is consistent with the putative mechanism of high concentrations of leaf apoplastic solutes as previously modeled for a halophyte, but an additional portion remains unexplained. Predawn leaf Psi (w) and xylem Psi (p) may not reflect soil Psi (w), particularly for woody plants and halophytes, even under well-watered conditions.
Author Address Univ Georgia, Dept Bot, Athens, GA 30602 USA; Eastern New Mexico Univ, Dept Biol, Portales, NM 88130 USA; Univ Calif Davis, Dept Land Air & Water Resources, Davis, CA 95616 USA
Reprint Address Donovan, LA (reprint author), Univ Georgia, Dept Bot, Athens, GA 30602 USA.
ResearcherID Number Donovan, Lisa/H-4754-2016
ORCID Number Donovan, Lisa/0000-0001-9814-0666
Cited References LU P, 1995, ANN SCI FOREST, V52, P117, DOI 10.1051/forest:19950203; FRANCO AC, 1994, OECOLOGIA, V97, P171, DOI 10.1007/BF00323146; Donovan LA, 1997, PLANT SOIL, V190, P105, DOI 10.1023/A:1004211207079; Sellin A, 1999, ACTA OECOL, V20, P51, DOI 10.1016/S1146-609X(99)80015-0; Le Roux X, 1998, OECOLOGIA, V113, P456; KLEPPER B, 1973, AGRON J, V65, P307; NILSEN ET, 1983, ECOLOGY, V64, P1381, DOI 10.2307/1937492; Maier-Maercker U, 1998, TREE PHYSIOL, V18, P211; Pockman WT, 2000, AM J BOT, V87, P1287, DOI 10.2307/2656722; MATYSSEK R, 1995, TREE PHYSIOL, V15, P159; Donovan LA, 1996, AM J BOT, V83, P1637, DOI 10.2307/2445840; Schwarzbach AE, 2001, AM J BOT, V88, P270, DOI 10.2307/2657018; Donovan LA, 1999, OECOLOGIA, V120, P209, DOI 10.1007/s004420050850; OURCIVAL JM, 1994, J ARID ENVIRON, V28, P333, DOI 10.1016/S0140-1963(05)80053-9; Schmidhalter U, 1997, PLANT CELL ENVIRON, V20, P953, DOI 10.1046/j.1365-3040.1997.d01-136.x; PASSIOURA JB, 1988, ANNU REV PLANT PHYS, V39, P245, DOI 10.1146/annurev.pp.39.060188.001333; JORDAN WR, 1971, PLANT PHYSIOL, V48, P783, DOI 10.1104/pp.48.6.783; Stirzaker RJ, 1996, PLANT CELL ENVIRON, V19, P201, DOI 10.1111/j.1365-3040.1996.tb00241.x; CERMAK J, 1980, BIOL PLANTARUM, V22, P34, DOI 10.1007/BF02878125; Very AA, 1998, PLANT J, V14, P509, DOI 10.1046/j.1365-313X.1998.00147.x; HINCKLEY TM, 1978, FOREST SCI, V24, P73; Zwieniecki MA, 2001, SCIENCE, V291, P1059, DOI 10.1126/science.1057175; Ameglio T, 1999, PLANT SOIL, V207, P155, DOI 10.1023/A:1026415302759; Richter H, 1997, J EXP BOT, V48, P1, DOI 10.1093/jxb/48.1.1; Caldwell MM, 1998, OECOLOGIA, V113, P151, DOI 10.1007/s004420050363; SALA OE, 1981, OECOLOGIA, V48, P327, DOI 10.1007/BF00346489; Benyon RG, 1999, TREE PHYSIOL, V19, P853; ELFVING DC, 1972, PHYSIOL PLANTARUM, V27, P161, DOI 10.1111/j.1399-3054.1972.tb03594.x; NOBEL PS, 1992, J EXP BOT, V43, P319, DOI 10.1093/jxb/43.3.319; BREDA N, 1995, PLANT SOIL, V172, P17, DOI 10.1007/BF00020856; Sellin A, 1996, PLANT SOIL, V184, P273, DOI 10.1007/BF00010456; Berger A, 1996, J TROP ECOL, V12, P607; GALLEGO HA, 1994, TREE PHYSIOL, V14, P1039; ANTLFINGER AE, 1983, AM J BOT, V70, P561, DOI 10.2307/2443167; Assaf G, 1996, J HORTIC SCI, V71, P673; BENNETT JM, 1985, PLANT PHYSIOL, V79, P184, DOI 10.1104/pp.79.1.184; BLAKE J, 1977, PHYSIOL PLANTARUM, V39, P106, DOI 10.1111/j.1399-3054.1977.tb04018.x; BOYERJS, 1965, MEASURING WATER STAT; BROWN RW, 1982, INT293 USDA FOR SERV; Caldwell M, 1985, PHYSL ECOLOGY N AM P, P198; COHEN Y, 1983, J EXP BOT, V34, P451, DOI 10.1093/jxb/34.4.451; Dahlgren RA, 1997, ARID SOIL RES REHAB, V11, P221; FAHEY TJ, 1984, OECOLOGIA, V61, P346, DOI 10.1007/BF00379633; GARNIER E, 1987, SCI HORTIC-AMSTERDAM, V32, P249, DOI 10.1016/0304-4238(87)90091-4; Graham EA, 1999, ANN BOT-LONDON, V84, P213, DOI 10.1006/anbo.1999.0911; HINCKLEY TM, 1973, AM MIDL NAT, V90, P56, DOI 10.2307/2424266; HINCKLEY TM, 1978, FOR SCI MONOGR, V20; KNAPP AK, 1995, AQUAT BOT, V49, P203, DOI 10.1016/0304-3770(94)00433-M; Kramer P.J., 1995, WATER RELATIONS PLAN; KUPPERS M, 1987, PLANT CELL ENVIRON, V10, P21; LASSOIE JP, 1983, ECOLOGY, V64, P1355, DOI 10.2307/1937490; MEINZER FC, 1988, OECOLOGIA, V77, P480, DOI 10.1007/BF00377263; NNYAMAH JU, 1978, SOIL SCI, V126, P63, DOI 10.1097/00010694-197808000-00001; Nobel PS, 1994, EXPLOITATION ENV HET, P285; OURCIVAL JM, 1995, J ARID ENVIRON, V30, P175, DOI 10.1016/S0140-1963(05)80068-0; Ritchie G. A., 1975, Advances in Ecological Research, V9, P165, DOI 10.1016/S0065-2504(08)60290-1; SAS, 1989, SAS STAT US GUID VER, V2; Schmidhalter U, 1998, AUST J PLANT PHYSIOL, V25, P307; Smith S.D., 1997, PHYSL ECOLOGY N AM D; SOBRADO MA, 1986, OECOLOGIA, V68, P413, DOI 10.1007/BF01036748; TURNER NC, 1988, IRRIGATION SCI, V9, P289, DOI 10.1007/BF00296704; WIESER G, 1993, TREES-STRUCT FUNCT, V7, P227
Cited Reference Count 62
Times Cited 114
Total Times Cited Count (WoS, BCI, and CSCD) 122
Publisher City NEW YORK
Publisher Address 175 FIFTH AVE, NEW YORK, NY 10010 USA
ISSN 0029-8549
29-Character Source Abbreviation OECOLOGIA
ISO Source Abbreviation Oecologia
Publication Date NOV
Year Published 2001
Volume 129
Issue 3
Beginning Page 328
Ending Page 335
Page Count 8
Web of Science Category Ecology
Subject Category Environmental Sciences & Ecology
Document Delivery Number 496VQ
Unique Article Identifier WOS:000172418100002
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