Physiological Acclimation

The response of ary alga towards UVB exposure is determined by the interplay of genetically fixed adaptation and physiological acclimation (Bischof et al 2006a). 

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Sensitivity of populations and communities to toxic stress may be influenced by exposure history. Tolerance can be acquired by an individual due to physiological acclimation or by genetic adaptation. At the community level, PICT may result from... 

The biochemical modifications of the photosynthetic apparatus caused by transfer to low DIC, cause a physiological acclimation which can be measured as an increased affinity for DIC [4]. 

Fig. 4. Convergence of numerous physiological functions, (a) and (b), including overall growth rate, at an optimum acclimation temperature which is...

Morphological plasticity and cellular acclimation When plants are exposed to stress as a consequence of resource depletion or climatic fluctuation, many different responses are possible depending upon the species and the nature and severity of the stress. However, as Bradshaw (1965) recognised, stress responses can be classified into two basic types, one of which is morphological and the other physiological. One of the major uses of plant strategy theory is to provide a basis for predicting which of the two mechanisms is likely to be operative in particular species, populations and situations. 

P. H. Saglio, M. C. Drew, and A. Pradet, Metabolic acclimation to anoxia induced by low (2-4kPa partial pressure) oxygen pre-treatment (hypoxia) in root tips of Zea mays, Plant Physiology S6 61 (1988). 

Lauren, D J. and D.G. McDonald. 1987a. Acclimation to copper by rainbow trout, Salmo gairdneri physiology. Canad. Jour. Fish. Aquat. Sci. 44 99-104. 

Other physiological functions of MAAs in phototrophic organisms such as organic osmolytes have been suggested, because very high concentrations can be found in cyanobacteria living in hypersaline environments (Oren 1997). However, salt shock experiments with the marine cyanobacterium Microcoleus chthono-plastes did not indicate ary major involvement of MAAs in the process of osmotic acclimation (Karsten 2002), and hence their proposed function as osmolytes has to be questioned. 

The subject of this chapter will be to summarise the biochemical and molecular changes which take place during the process of cold acclimation and the acquisition of freezing stress tolerance. We will discuss how polypeptides correlated with the acclimation process might play a role in increased cold tolerance and we will focus on recent results emerging from molecular studies. For further treatment of the subject the reader is referred to a number of recent review articles (Steponkus, 1984 Guy, 1990 Thomashow, 1990). The biochemistry and physiology of cold acclimation is described in detail by Levitt (1980). 

Many physiological studies established a correlation between cold acclimation and increasing ABA levels in plant tissues (Chen etal., 1983). Furthermore, exogenous ABA application can induce cold-hardening to the same degree as a low temperature treatment does (Chen Gusta, 1983) while plant species which do not show a hardening capacity at low temperature do not harden even after ABA treatment. 

Chen, H.-H., Li, P.H. Brenner, M.L. (1983). Involvement of abscisic acid in potato cold acclimation. Plant Physiology 71, 362-5. 

Gilmour, S.J., Hajela, R.K. Thomashow, M.F. (1988). Cold acclimation in Arabidopsis thaliana. Plant Physiology 87, 745-50. 

Guy, C.L. (1990). Cold acclimation and freezing stress tolerance role of protein metabolism. Annual Review of Plant Physiology and Plant Molecular Biology 41, 187-223. 

Guy, C.L. Haskell, D. (1987). Induction of freezing tolerance in spinach is associated with the synthesis of cold acclimation induced proteins. Plant Physiology 84, 872-8. 

Kushad, M.M. Yelenosky, G. (1987). Evaluation of polyamine and proline levels during low temperature acclimation of citrus. Plant Physiology 84, 692-5. 

Lynch, D.V. Steponkus, P.L. (1987). Plasma membrane lipid alterations associated with cold acclimation of winter rye seedlings (Secale cereale L. cv. Puma). Plant Physiology 83, 761-7. 

Mohapatra, S.S., Poole, R.J. Dhindsa, R.S. (1987a). Changes in protein patterns and translatable messenger RNA populations during cold acclimation of alfalfa. Plant Physiology 84, 1172-6. 

Perras, M. Sarhan, F. (1989). Synthesis of freezing tolerance proteins in leaves, crown, and roots during cold acclimation of wheat. Plant Physiology 89, 577-85. 

Sarhan, F. Chevrier, N. (1985). Regulation of RNA synthesis by DNA-dependent RNA polymerases and RNases during cold acclimation in winter and spring wheat. Plant Physiology 78, 250-5. 

Steponkus, P.L. (1984). Role of the plasma membrane in freezing injury and cold acclimation. Annual Review of Plant Physiology 35, 543-84. 

Campbell, C.M. and Davis, P.S. (1978). Temperature acclimation in the teleost, Blennius pholis, changes in enzyme activity and cell structure. Comparative Biochemistry and Physiology 61B, 165-167. 

Christiansen, J.A. (1984). Changes in phospholipid classes and fatty acid desaturation and incorporation into phospholipids during temperature acclimation of green sunfish, Lepomis cyanellus. Physiological Zoology 57,481-492. 

Driedzic, W., Selivonchick, D.P. and Roots, B.J. (1976). Alk-l-enyl ether-containing lipids of goldfish brain and temperature acclimation. Comparative Biochemistry and Physiology 53B, 311-314. 

Hagar, A.F. and Hazel, J.R. (1985). Changes in desaturase activity and the fatty acid composition of microsomal membranes from liver tissue of thermally-acclimating rainbow trout. Journal of Comparative Physiology 156B, 35-42. 

Hazel, J.R. (1972). The effect of temperature acclimation upon succinic dehydrogenase activity from the muscle of common goldfish lipid reactivation of the soluble enzyme. Comparative Biochemistry and Physiology 43B, 863-882. 

Hazel, J.R. (1979). Influence of thermal acclimation of membrane lipid composition of rainbow trout. American Journal of Physiology 236,91-101. 

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