Suberin ultrastructure

Ryser U. 1992. Ultrastructure of the epidermis of developing cotton Gossypium) seeds Suberin, pits, plasmodesmata, and their implications for assimilate transport into cotton fibers. Amer J Bot 79 14-22. 

Suberized layers in plant roots have been ultrastructurally characterized in detail (457). The characteristic lamellar appearance has been observed in the en-dodermal cell walls of the roots of several plants (286, 309, 381, 403, 495). Similarly, suberin layers have been observed in hypodermal and epidermal cells of plant roots (77, 78, 122, 174, 334, 365, 366, 380, 498). Lamellar suberin has also been ultrastructurally characterized at various internal locations in the plant such as the bundle sheath of grasses (51, 118, 173, 331, 332), the chalazal region of the seedcoat (111), and in the cell wall of crystal idioblasts (441, 479, 480) (Fig. 6.4.3). 

Suberin also plays a role in cold stress. The periderm layers in the bark serve as insulation for the plant (110). Thus suberin deposition in the bark of Vitis vinifera was shown to protect the plant from freezing damage (303, 351). The leaves of Secale cereale were shown by both ultrastructural and chemical analysis to deposit increased levels of aliphatic components in the epidermis and in the mestome sheath in response to growth at low temperatures (146). 

Ultrastructural studies indicated that suberin is deposited in seeds, when they reach maturity, as a means of sealing off the seed where vascular tissue was attached. Thus suberin was shown to be deposited in the pigment strand of Triticum... 

Suberin is laid down in the cell wall of calcium oxalate crystal idioblasts. This deposition has been characterized in crystal cells in the bark of Larix decidua, Acacia Senegal, and Picea abies (481, 482). The suberin in crystal idioblast cell walls from Agave americana was characterized both ultrastructurally (Fig. 6.4.3) and chemically, and the major aliphatic component was shown to be octadocenedioic acid (25%) (117). The basal walls of leaf trichomes are suberized as shown in Abutilon megapotamicum (161), Ananas comosus (395), and Larrea tridentata (451). The walls of oil cells found in Acorus calamus (9) and Laurus nobilis (291) also appear ultrastructurally to be suberized. Suberized cells encircle silica cells in the stem of Lolium temulentum (271). In all of the cases listed above, the suberin may serve to protect the rest of the plant from potentially toxic components. 

Dean B B, Kolattukudy P E, Davis R W 1977 Chemical composition and ultrastructure of suberin from hollow heart tissue of potato tubers Solarium tuberosum). Plant Physiol 59 1008-1010... 

Espelie K E, Davis R W, Kolattukudy P E 1980 Composition, ultrastructure and function of the cutin- and suberin-containing layers in the leaf, fruit peel, juice-sac and inner seed coat of grapefruit Citrus paradisi Macfed.). Planta 149 498-511... 

Ryser U, Holloway P J 1985 Ultrastructure and chemistry of soluble and polymeric lipids in cell walls from seed coat fibres of Gossypium species. Planta 163 151-163 Ryser U, Meier H, Holloway P J 1983 Identification and localization of suberin in the cell walls of green cotton fibres Gossypium hirsutum L., var. green lint). Protoplasma 117 196-205 Sagisaka S 1976 The occurrence of peroxide in a perennial plant, Populus gelrica. Plant Physiol 57 308-309... 

Soliday C L, Kolattukudy P E, Davis R W 1979 Chemical and ultrastructural evidence that waxes associated with the suberin polymer constitute the major diffusion barrier to water vapor in potato tuber Solanum tuberosum L.). Planta 146 607-614... 

Wattendorff J 1974 The formation of cork cells in the periderm of Acacia Senegal Willd. and their ultrastructure during suberin deposition. Z Pflanzenphysiol 72 119-134... 

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