Cellular acclimation

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. 

Fourier Transform Infra Red Spectroscopy, Arrhenius plots of rate vs. temperature of a membrane-linked phenomenon) that biological membranes from nonhibemat-ing or cold acclimated animals show a phase transition around 12 °C to 17 °C. Thus, at useful cold storage temperatures, it is expected that the plasma membrane and membranes of the cellular organelles will be mostly in a gel or solid state. 

Knight, H., Trewavas, A.J. and Knight, M.R., 1996, Cold calcium signaling in Arabidopsis involves two cellular pools and a change in calcium signature after acclimation. Plant Cell 8 489-503. 

Selote, D.S., and R. Khanna-Chopra. 2006. Drought acclimation confers oxidative stress tolerance by inducing co-ordinated antioxidant defense at cellular and subcellular level in leaves of wheat seedlings. Physiol. Plant. 127 494—506. 

Temperature acclimation of plants is Icnown to be connected with the increased resistance of munerous cellular structures and functions (1,2). But if some authors think that adaptation is based on temperature induced conformational rearrangements of macromolecules (1), the others see its reason in a quantitative and qualitative changes observed in the protein complex of a cell (3) We believed (4), that both above mechanisms function in plants mutually supplemeting each other. It is assumed that a real contribution of each of them is dependent on the Intensity and duration of temperature effects, biological characteristics of the object and on occumpanying conditions (illumination, humidity, etc). 

Plants are routinely exposed to a bewildering variety of environmental stresses. Considering the extremes of temperature, salinity, moisture level, etc. that must be overcome, it is perhaps surprising that plant life is distributed as widely as it is. The key to survival lies in the remarkable capacity of many plants to acclimate to changing conditions. Such an acclimation is necessary because the patterns of cellular composition and metabolism favoring productive growth under one set of conditions usually do not suffice under different conditions. 

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