200
R. Losch and E.-D. Schulze
in the soil-plant-atmosphere continuum with two compartments of highly
variable water relations.
- One can speculate whether it is a basic attribute of living organisms
that they attempt optimally not only to react by feedback regulation to
changes in their environment but also by adapting themselves, by means
of feedforward mechanisms, to a variety of circumstances. This will
allow them to cope much more effectively with forthcoming or locally
heterogeneous situations.
- The combination of feedforward and feedback mechanisms acting at the
same regulatory point may give the necessary flexibility to respond in a
variable environment.
- The coordination at the stomatal level is not sufficient to stabilize plant
water status. The same signals appear to affect growth also. Thus, coordination in plant transpiration and structure is achieved. Detailed information is still lacking, however, as to how this goal is achieved functionally.
References
Aspinall D (1986) Metabolic effects of water and salinity stress in relation to expansion of
the leaf surface. Aust J Plant Physiol 13: 59-73
Aston MJ, Lawlor DW (1979) The relationship between transpiration, root water uptake,
and leaf water potential. J Exp Bot 30: 169-181
Atkinson CJ, Davies WJ, Mansfield T A (1989) Changes in stomatal conductance in intact
ageing wheat leaves in response to abscisic acid. J Exp Bot 40: 1021-1028
Barlow EWR (1986) The water relations of expanding leaves. Aust J Plant Physiol 13:
45-58
Bates LM, Hall AE (1981) Stomatal closure with soil water depletion not associated with
changes in bulk leaf water status. Oecologia 50: 62-65
Beardsell MF, Cohen D (1975) Relationships between leaf water status, abscisic acid
levels and stomatal resistance in maize and sorghum. Plant Physiol 56: 207-212
Behl R, Hartung W (1986) Movement and compartmentation of abscisic acid in guard
cells of Valerianella locusta: effects of osmotic stress, external H+ -concentration and
fusicoccin. Planta 168: 360-368
Berard RG, Thurtell GW (1991) The interactive effects of increased evaporative demand
and soil water on photosynthesis in maize. Can J Plant Sci 71: 31-39
Biscoe PV, Cohen Y, Wallace JS (1976) Daily and seasonal changes of water potential in
cereals. Philos Trans R Soc Lond B 273: 565-580
Blackman PG, Davies WJ (1984) Modification of the CO2 responses of maize stomata by
abscisic acid and by naturally occurring and synthetic cytokinins. J Exp Bot 35:
174-179
Blackman PG, Davies WJ (1985) Root-to-shoot communication in maize plants of the
effects of soil drying. J Exp Bot 36: 39-48
Bradford KJ, Hsiao TC (1982) Physiological responses to moderate water stress. In:
Lange OL, Nobel PS, Osmond CB, Ziegler H (eds) Physiological plant ecology II,
Encycl Plant Phys, NS 12B. Springer, Berlin Heidelberg New York, pp 263-324
Cowan IR (1977) Stomatal behavior and environment. Adv Bot Res 4: 117-288
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) Physiological plant ecology II,
Encycl. Plant Phys NS 12B. Springer, Berlin Heidelberg New York, pp 589-614
R. Losch and E.-D. Schulze
in the soil-plant-atmosphere continuum with two compartments of highly
variable water relations.
- One can speculate whether it is a basic attribute of living organisms
that they attempt optimally not only to react by feedback regulation to
changes in their environment but also by adapting themselves, by means
of feedforward mechanisms, to a variety of circumstances. This will
allow them to cope much more effectively with forthcoming or locally
heterogeneous situations.
- The combination of feedforward and feedback mechanisms acting at the
same regulatory point may give the necessary flexibility to respond in a
variable environment.
- The coordination at the stomatal level is not sufficient to stabilize plant
water status. The same signals appear to affect growth also. Thus, coordination in plant transpiration and structure is achieved. Detailed information is still lacking, however, as to how this goal is achieved functionally.
References
Aspinall D (1986) Metabolic effects of water and salinity stress in relation to expansion of
the leaf surface. Aust J Plant Physiol 13: 59-73
Aston MJ, Lawlor DW (1979) The relationship between transpiration, root water uptake,
and leaf water potential. J Exp Bot 30: 169-181
Atkinson CJ, Davies WJ, Mansfield T A (1989) Changes in stomatal conductance in intact
ageing wheat leaves in response to abscisic acid. J Exp Bot 40: 1021-1028
Barlow EWR (1986) The water relations of expanding leaves. Aust J Plant Physiol 13:
45-58
Bates LM, Hall AE (1981) Stomatal closure with soil water depletion not associated with
changes in bulk leaf water status. Oecologia 50: 62-65
Beardsell MF, Cohen D (1975) Relationships between leaf water status, abscisic acid
levels and stomatal resistance in maize and sorghum. Plant Physiol 56: 207-212
Behl R, Hartung W (1986) Movement and compartmentation of abscisic acid in guard
cells of Valerianella locusta: effects of osmotic stress, external H+ -concentration and
fusicoccin. Planta 168: 360-368
Berard RG, Thurtell GW (1991) The interactive effects of increased evaporative demand
and soil water on photosynthesis in maize. Can J Plant Sci 71: 31-39
Biscoe PV, Cohen Y, Wallace JS (1976) Daily and seasonal changes of water potential in
cereals. Philos Trans R Soc Lond B 273: 565-580
Blackman PG, Davies WJ (1984) Modification of the CO2 responses of maize stomata by
abscisic acid and by naturally occurring and synthetic cytokinins. J Exp Bot 35:
174-179
Blackman PG, Davies WJ (1985) Root-to-shoot communication in maize plants of the
effects of soil drying. J Exp Bot 36: 39-48
Bradford KJ, Hsiao TC (1982) Physiological responses to moderate water stress. In:
Lange OL, Nobel PS, Osmond CB, Ziegler H (eds) Physiological plant ecology II,
Encycl Plant Phys, NS 12B. Springer, Berlin Heidelberg New York, pp 263-324
Cowan IR (1977) Stomatal behavior and environment. Adv Bot Res 4: 117-288
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) Physiological plant ecology II,
Encycl. Plant Phys NS 12B. Springer, Berlin Heidelberg New York, pp 589-614