The Energetic Basis of Osmotolerance in Plants: Physical Principles

The current impasse in breeding for osmotolerance in plants has deep-seated reasons. The theoretical nature of the problem is not understood by the experimental biologists and agriculturists. Conversely, the diversity of the classes of responses that beset the experimenter are not anticipated by the theoretician. The evidence is mounting in favor of a diffusive mechanism for control of growth by the osmolarity of the medium/soil for plants and microbes. We examined a series of models as a locus of interaction of osmolarity of the medium and the simulations revealed a vast spectrum of possible biological behaviors. Of these, the diffusive mechanism for control velocity of respiratory enzymology was most dominant. The osmotic phenomena were re-evaluated by systematizing the theory in terms of time dependent changes in the organism, as initial responses and subsequent regulatory responses. The theoretical work presented herein leads some novel experimental approaches to define the problem of limits to yield by methods not thus far employed in plant research.