SUPERCELLULAR PLANT-ORGANIZATION

The application of confocal microscopy and other innovative methods to plant structure studies supported the idea of a mobile endoplasmic ne twork unsubdivided into cells. The concept of mobile symplasmic transp ort networks that are discontinued only in zones where plasmodesmata a re blocked or missing has been enriched with evidence for the similari ty of apoplasm structure, with its hydrophilic and hydrophobic zones. The flexible domain organization of the transport networks, within or outside cytoplasm, demands that the classification of plant structures be supplemented with a network (supercellular) level, The cell-networ k concept was previously put forward by the author and critically disc ussed in this journal; in this review, the concept is further explored in the following areas: (1) initial development, in the course of gre en eukaryote evolution, of the transport system from the buffer zone o f endosymbiotic partners; (2) transformation, through a series of phyl ogenetic and ontogenetic events, of the radial endoplasmic and exoplas mic networks in parenchyma into the major axial channels of phloem and xylem; (3) structural interrelations of cell cytoplasm, organelles, a nd transport networks; (4) photosynthesis-dependent development of end oplasmic networks and plasmodesmata; (5) diurnal and seasonal changes in plasmodesm functioning; (6) the rhythmic pattern of plant developme nt as related to reversible and irreversible changes in plasmodesmata and transport networks; (7) mechanisms that control the plant-cell rel ationship; (8) coordination of integrating functions in natural and ex perimental environments as related to the diversity of Life-forms mani fested by plant species; (9) the cell-network model of plant developme nt and its modifications due to modified functional interactions betwe en photosynthesis, respiration, and assimilate storage and export; (10 ) the future structural studies of the plant transport system and meta bolite distribution in the context of metabolic control over gene expr ession in cytoplasm and organelles.