ECONOMIC-MODEL OF A PLANT - A GENERAL-APPROACH

An economic model for describing a whole plant is suggested. The primary assumption in reconstructing the costs of a plant is based on the belief that its actually observed life activity is optimal. The life activity of the plant is considered from the hierarchy of its costs. An optimization principle is chosen at each level of the hierarchy; the principle implies that maximal efficiency of material and energy costs takes place. It is suggested that the decrease in efficiency (in terms of material and energy costs) can be considered as a criterion for deviation from the optimal state. The process of photosynthesis was preferred to start the economic description of a plant because the costs and resulting product can be expressed in the same units. It was suggested that the total plant costs be separated into two isolated groups: water transport and reproduction of the photosynthetic apparatus (in the broad sense of the term, from a microscopic to organismic level). The developed approach is promising for identifying the interrelations between all the diverse physiological processes in plants (photosynthesis, water exchange, translocation of assimilates, etc.).