, Volume 99, Issue 3–4, pp 306–314 | Cite as

Above- and below-ground environmental influences on leaf conductance ofCeanothus thyrsiflorus growing in a chaparral environment: drought response and the role of abscisic acid

  • J. D. Tenhunen
  • R. Hanano
  • M. Abril
  • E. W. Weiler
  • W. Hartung
Original Paper


Small shrubs ofCeanothus thyrsiflorus were grown in 19-1 pots irrigated under natural conditions in a chaparral region of Southern California and then subjected to soil drying. Characteristics of leaf gas exchange, leaf water potential, and concentrations of the stress hormone abscisic acid in the xylem sap, ABAxyl, were determined at various stages of drought. Diurnal changes in conductance were strongly correlated with leaf net photosynthesis rate, which provides an effective, integrative predictor of above-ground climate effects on conductance. In drought conditions, ABAxyl concentration increased. Increases in the concentration range of 50–500 nmol/l appeared to induce stomatal closure, restricting water loss and carbon dioxide uptake. When the momentary water potential is related to ABAxyl, ABA appeared to increase significantly only after a threshold of approximately −1.5 MPa was exceeded. At less negative water potentials, large variation in ABAxyl in the 50–1000 nmol/l range occurred for all water-potential values, because ABAxyl remains relatively constant over diurnal courses as water potentials decrease and then recover. When the water potential became more negative than −1.5 MPa, ABAxyl concentrations occurred between approximately 500 and 10 000 nmol/l and even greater in isolated cases. An approximately linear relationship is recognizable between ABAxyl and momentary water potential in this range because in plants under drought conditions, ABAxyl increases during the course of the day as water potential decreases. Increases in ABAxyl in the high concentration range were associated with relatively minor additional restrictions in gas exchange, but they might contribute to improved water use efficiency and explain diurnal changes in the potential for stomatal opening that have been observed in Mediterranean sclerophyllous species. When we examined long-term seasonal change in the response of irrigated plants, changes in average daily temperature greater than 10°C occurred (also associated with shifts in relative humidity and radiation input), which apparently led to small changes in predawn water potential in the −0.1 to −0.7 MPa range. Increases in ABAxyl occurred that were in turn negatively correlated with daily maximum leaf conductance. Thus, chaparral shrubs under non-drought conditions seem to sense even small changes in environmental conditions, in our opinion most probably due to initial drying of the uppermost soil and synthesis of ABA in the shallow roots. The results support the hypothesis that information of photosynthesis rate and predawn water potential may be used as primary variables to predict canopy conductance of Mediterranean sclerophyll shrub vegetation.

Key words

Abscisic acid Chaparral Ceanothus thyrsiflorus Conductance Photosynthesis 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Acherar M, Rambal S (1992) Comparative water relations of four Mediterranean oak species. Vegetatio 99–100:177–184Google Scholar
  2. Ball JT, Woodrow IE, Berry JA (1987) A model predicting stomatal conductance and its contribution to the control of photosynthesis under different environmental conditions. In: Biggins I (ed) Progress in photosynthesis research, vol IV.5. Proceedings of the VII International Photosynthesis Congress,o pp 221–224Google Scholar
  3. Bartels D, Schneider K, Terstappen G, Piatkowski D, Salamini F. (1990) Molecular cloning of abscisic acid-modulated genes which are induced during desiccation of the resurrection plantCraterostigma plantagineum. Planta 181:27–34Google Scholar
  4. Beyschlag W, Lange OL, Tenhunen JD (1986) Photosynthese und Wasserhaushalt vonArbutus unedo L. im Jahreslauf am Freilandstandort in Portugal. I. Tagesläufe von Photosynthese und Transpiration unter natürlichen Bedingungen. Flora 178:409–444Google Scholar
  5. Beyschlag W, Pfanz H, Ryel R (1992) Stomatal patchiness in Mediterranean evergreen sclerophylls; phenomenology and consequences for the interpretation of the midday depression in photosynthesis and transpiration. Planta 187:546–553Google Scholar
  6. Burschka C, Tenhunen JD, Hartung W (1983) Diurnal variations in abscisic acid content and stomatal response to applied abscisic acid in leaves of irrigated and non irrigatedArbutus unedo plants under naturally fluctuating environmental conditions. Oecologia 58:285–289Google Scholar
  7. Cowan, IR (1982) Regulation of water use in relation to carbon gain in higher plants. In: Lange OL, Nobel PS, Osmond CB, Ziegler H (eds), Encyclopedia of plant physiology, vol 12B. Physiological Plant Ecology. Springer, Berlin Heidelberg New York, pp 589–613Google Scholar
  8. Davies WJ, Zhang J (1991) Root signals and the regulation of growth and development of plants in drying soil. Annul Rev Plant Physiol Plant Mol Biol 42:55–76Google Scholar
  9. Gollan T, Schurr U, Schulze E-D (1992) Stomatal response to drying soil in relation to changes in xylem sap composition ofHelianthus annuus. 1. The concentration of cations, anions, amino acids in, and pH of, the xylem sap. Plant Cell Environ 15:551–559Google Scholar
  10. Hartung W, Davies WJ (1991) Drought induced changes in physiology and ABA. In: Davies WJ, Jones HG (eds) Abscisic acid. Bios, Oxford, pp 63–79Google Scholar
  11. Hartung W, Heilmeier H (1993) Stomatal responses to abscisic acid in natural environments. In: Jackson MB (ed) Interacting stresses on plants in a changing climate. (NATO-ASI series), Springer, Berlin Heidelberg New York, pp 525–541Google Scholar
  12. Hartung W, Slovik S (1991) Physicochemical properties of plant growth regulators and plant tissues determine their distribution and redistribution: stomatal regulation by abscisic acid in leaves. New Phytol 119:361–382Google Scholar
  13. Hartung W, Heilmeier H, Wartinger A, Kettemann I, Schulze E-D (1990) Ionic content and abscisic acid relations ofAnastatica hierochuntica L. under arid conditions. Is J Bot 39:373–382Google Scholar
  14. Hinckley TM, Duhme F, Hinckley AR, Richter H (1983) Drought relations of shrub species: assessment of the mechanism of drought resistance. Oecologia 59:344–350Google Scholar
  15. Kelliher FM, Leuning R, Schulze E-D (1993) Evaporation and canopy characteristics of coniferous forest and grassland. Oecologia 95:153–163Google Scholar
  16. Lange OL, Harley PC, Beyschlag W, Tenhunen JD (1987) Gas exchange methods for characterizing the impact of stress on leaves. In: Tenhunen JD, Catarino F, Lange OL, Oechel WC (eds) Plant response to stress—functional analysis in Mediterranean ecosystems. Springer, Berlin Heidelberg New York, pp 3–25Google Scholar
  17. Lawrence W (1987) Gas exchange characteristics of representative species from the scrub vegetation of central Chile. In: Tenhunen JD, Catarino F, Lange OL, Oechel WC (eds.), Plant response to stress — functional analysis in Mediterranean ecosystems. Springer, Berlin Heidelberg New York, pp 279–304Google Scholar
  18. Meterns RJ, Deus-Neumann B, Weiler EW (1985) Monoclonal antibodies for the detection and quantitation of the endogenous plant growth regulator, abscisic acid. FEBS Lett 160:269–272Google Scholar
  19. Oechel WC, Lawrence W, Mustafa J, Martinez J (1981) Energy and carbon allocation. In: Miller PC (ed) Resource use by Chaparral and Matorral. Springer, Berlin Heidelberg New York, pp 151–183Google Scholar
  20. Radin JW, Hartung W, Kimball BA, Mauney JR (1988) Correlation of stomatal conductance with photosynthetic capacity of cotton only in a CO2-enriched atmosphere: mediation by abscisic acid? Plant Physiol 88:1058–1062Google Scholar
  21. Schurr U, Gollan T, Schulze E-D (1992) Stomatal response to drying soil in relation to changes in the xylem sap composition ofHelianthus annuus. II. Stomatal sensitivity to abscisic acid imported from the xylem sap. Plant Cell Environ 15:561–567Google Scholar
  22. Tardieu F, Davies WJ (1993) Integration of hydraulic and chemical signalling in the control of stomatal conductance and water status of droughted plants. Plant Cell Environ 16:341–349Google Scholar
  23. Tardieu F, Zhang J, Katerji N, Bethenod O, Palmer S, Davies WJ (1992) Xylem ABA controls the stomatal conductance of field-grown maize to soil compaction or soil drying. Plant Cell Environ 15:193–197Google Scholar
  24. Tenhunen JD, Beyschlag W, Lange OL, Harley PC (1987a) Changes during summer drought in leaf CO2 uptake rates of macchia shrubs growing in Portugal: Limitations due to photosynthetic capacity, carboxylation efficiency, and stomatal conductance. In: Tenhunen JD, Catarino F, Lange OL, Oechel WC (eds) Plant response to stress-Functional analysis in Mediterranean ecosystems. Springer, Berlin Heidelberg New York, pp 305–327Google Scholar
  25. Tenhunen JD, Pearcy RW, Lange OL (1987b) Diurnal variation in leaf conductance and gas exchange in natural environments. In: Zeiger E, Farquhar G, Cowan I (eds) Stomatal function. Stanford University Press, Stanford, Calif, pp 323–351Google Scholar
  26. Tenhunen JD, Reynolds JF, Lange OL, Dougherty R, Harley PC, Kummerow J, Rambal S (1989) QUINTA: A physiologicallybased growth simulator for drought adapted woody plant species. In: Pereira JS, Landsberg JJ (eds) Biomass production by fast-growing trees, (NATO ASI series, Applied Science vol 166) Kluwer, Dordrecht, The Netherlands, pp 135–168Google Scholar
  27. Tenhunen JD, Sala Serra A, Harley PC, Dougherty RL, Reynolds JF (1990) Factors influencing carbon fixation and water use by Mediterranean sclerophyll shrubs during summer drought. Oecologia 82:381–393Google Scholar
  28. Walter H (1977) Vegetationszonen und Klima. Eugen Ulmer, Stuttgart, pp 309Google Scholar
  29. Wartinger A, Heilmeier H, Hartung W, Schulze E-D (1990) Daily and seasonal courses of leaf conductance and abscisic acid in the xylem sap of almond trees (Prunus dulcis (Miller) D.A. Webb) under desert conditions. New Phytol 116:581–587Google Scholar

Copyright information

© Springer Verlag 1994

Authors and Affiliations

  • J. D. Tenhunen
    • 1
  • R. Hanano
    • 2
  • M. Abril
    • 3
    • 4
  • E. W. Weiler
    • 5
  • W. Hartung
    • 2
  1. 1.Lehrstuhl für Pflanzenökologie, Bayreuther Institut für Terrestrische Ökosystemforschung (BITÖK)Universität BayreuthBayreuthGermany
  2. 2.Julius von Sachs Institut für Biowissenschaften, Lehrstuhl für Botanik IUniversität WürzburgWürzburgGermany
  3. 3.CREAF Universitat Autònoma de BarcelonaBellaterraSpain
  4. 4.Departament D'EcologiaUniversitat de BarcelonaBarcelonaSpain
  5. 5.Lehrstuhl PflanzenökologieRuhr Universität BochumBochumGermany

Personalised recommendations