The Chemistry of Secondary Growth in Trees Including Related Biochemical, Botanical, and Biophysical Aspects

摘要

This paper presents a review of recent advances concerning various chemical, biochemical, and botanical aspects of secondary growth in trees. The biosynthesis of the major essential nutrients (carbohydrates and amino acids) required for secondary growth and the means whereby the nutrients are translocated from the site of synthesis to the differentiating secondary tissues are discribed. Various methods of obtaining samples of plant fluids are outlined. The results of analyses of such samples and the significance of the analytical data are discussed in terms of the nutrients required for and of the byproducts produced during secondary growth. The physical and chemical changes associated with the differentiation of cell elements and of whole tissues in the phloem and, particularly, in the xylem are discussed in considerable detail. Some aspects of stem anatomy and of cell-wall organization are considered in relation to their importance to chemical studies of secondary growth. The chemical structure of cellulose, of the acidic polysaccharides, and of the heteroglycans of the cell wall are described briefly. Some consideration is given to lignin-carbohydrate complexes, to the comparative chemistry of vascular plants, to the mechanism of heartwood formation, and to reactions which may occur in the non-functioning tissues of living trees.