ENERGETIC ASPECT OF RADIAL WATER TRANSPORT ACROSS THE BEAN ROOT (PHASEOLUS-VULGARIS L)

This paper investigates a bean root (Phaseolus vulgaris L.) approximat ed to the one-membrane system. For the root of this plant treated in t his way are given in Fiscus paper from 1986 the numerical values of th e coefficients of filtration (L(p)BAR), reflection (sigmaBAR), and per meation (omegaBAR). The thermodynamic formalism of Kedem and Katchalsk y (1958) and die method of quantitative analysis of osmotic - diffusiv e conversion of free energy (Kargol 1990) were applied. A number of en ergetic properties of the bean root were analyzed in relation to water transport through the radial duct and xylem rise (up to a certain hei ght) on the basis of osmotically generated root pressure. The main ach ievement of this work (interesting from the physiological point of vie w) is the observation that the energetic efficiency of root connected with water transport ought not to depend on concentration C(o) of the medium solution in which this root is. This property refers to concent rations C(o) from the interval: 0<C(o)<11 [mole m-3].