Summary
Parenchyma cells of the secondary phloem in Pinus strobus have all the cellular organelles common in other plant cells. They have mitochondria, endoplasmic reticulum, ribosomes, dictyosomes, and plastids. Parenchyma cells are very conspicuous because of their organic inclusions, starch and lipids. Plasmodesmata in transverse and tangential walls of axial parenchyma cells and in end walls of ray parenchyma cells are regularly distributed and of uniform size, about 500 Å in diameter. In radial walls of axial parenchyma cells and horizontal walls of ray parenchyma cells plasmodesmata are located in primary pit-fields; there they are of variable size and often divided into several branches. The branches are confluent into a median nodule. Perforation of the transverse wall between two axial parenchyma cells and the resultant union of the cellular material of the two connected cells is reported.
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Literature
Bopp-Hassenkamp, G.: „Cytomixis” im elektronenmikroskopischen Bild. Exp. Cell Res. 18, 182–184 (1959).
Buvat, R.: L'infrastructure des plasmodesmes dans les cellules parenchymateuses des cordons conducteurs jeunes de Cucurbita pepo L. C.R. Acad. Sci. (Paris) 250, 170–172 (1960).
—, et A. Puissant: Observations sur la cytodiérèse et l'origine des plasmodesmes. C. R. Acad. Sci. (Paris) 247, 233–235 (1958).
Esau, K., and V. I. Cheadle: Cytologic studies on phloem. Univ. Calif. Publ. Bot. 36, 253–344 (1965).
——, and E. B. Risley: A view of ultrastructure of Cucurbita xylem. Bot. Gaz. 124, 311–316 (1963).
Evert, R. T.: Phloem structure in Pyrus communis L., and its seasonal changes. Univ. Calif. Publ. Bot. 32, 127–194 (1960).
—: Ontogeny and structure of the secondary phloem in Pyrus malus. Amer. J. Bot. 50, 8–37 (1963).
—, and F. J. Alfieri: Ontogeny and structure of coniferous sieve cells. Amer. J. Bot. 52, 1058–1066 (1965).
— L. Murmanis, and I. B. Sachs: Another view of the ultrastructure of Cucurbita phloem. Ann. Bot. 30, 563–585 (1966).
Fischer, A.: Beiträge zur Physiologie der Holzgewächse. Jb. wiss. Bot. 22, 73–160 (1891).
Frey-Wyssling, A., and K. Mühlethaler: Cell wall. In: Ultrastructural plant cytology. New York: Elsevier Publ. Co. 1965.
— J. F. Lopez-Saez, and K. Mühlethaler: Formation and development of the cell plate. J. Ultrastruct. Res. 10, 422–432 (1964).
Gates, R. R.: Pollen formation in Oenothera gigas. Ann. Bot. 25, 909–940 (1911).
Kamra, O. P.: Chromatin extrusion and cytomixis in pollen mother cells of Hordeum. Hereditas (Lund) 46, 592–600 (1960).
Kienitz-Gerloff, F.: Die Plasmaverbindungen zwischen benachbarten Gewebselementen in der Pflanze. Bot. Z. 49, 17–26 (1891).
Krull, R.: Untersuchungen über den Bau und die Entwicklung der Plasmodesmen im Parenchym von Viscum album. Planta (Berl.) 55, 598–629 (1960).
Kuhla, F.: Die Plasmaverbindungen bei Viscum album. Bot. Z. 58, 29–58 (1900).
Leyon, H.: The structure of chloroplasts. VI. The origin of the chloroplast laminae. Exp. Cell Res. 7, 609–611 (1954).
Livingstone, L. G.: The nature and distribution of plasmodesmata in the tobacco plant. Amer. J. Bot. 22, 75–87 (1935).
—: The nature of plasmodesmata in normal (living) plant tissue. Amer. J. Bot. 51, 950–957 (1964).
Maheshwari, P.: An introduction to the embryology of angiosperms. New York: McGraw-Hill Book Co. 1950.
Meeuse, A. D. J.: Plasmodesmata. Bot. Rev. 7, 249–262 (1941).
Murmanis, L., and R. F. Evert: Some aspects of sieve cell ultrastructure in Pinus strobus. Amer. J. Bot. (in press) (1966).
Northcote, D. H., and J. D. Pickett-Heaps: A function of the Golgi apparatus in polysaccaride synthesis and transport in the root-cap cells of wheat. Biochem. J. 98, 159–167 (1966).
Sarvella, P.: Cytomixis and the loss of chromosomes in meiotic and somatic cells of Gossypium. Cytologia (Tokyo) 23, 14–24 (1958).
Sassen, M. M. A.: Breakdown of the plant cell wall during the cell fusion process. Acta bot. neerl. 14, 165–196 (1965).
Strasburger, E.: Über Plasmaverbindungen pflanzlicher Zellen. Jb. wiss. Bot. 36, 493–610 (1901).
Takats, S. T.: Chromatin extrusion and DNA transfer during microsporogenesis. Chromosoma (Berl.) 10, 430–453 (1959).
Webb, J. A., and P. R. Gorham: Translocation of photosynthetically assimilated C14 in the straight-necked squash. Plant Physiol. 39, 663–672 (1964).
—, and P. R. Gorham: Radial movement of C14-translocates from squash phloem. Canad. J. Bot. 43, 97–105 (1965).
Welling, F.: Licht- und elektronenmikroskopische Beobachtungen zum Problem der Cytomixis sowie ihrer möglichen Beziehung zur Photocytose. Planta (Berl.) 67, 182–212 (1965).
Zimmermann, M. H.: Translocation of organic substances in trees. III. The removal of sugars from sieve tubes in the white ash (Fraxinus americana L.). Plant Physiol. 33, 213–217 (1958).
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This research has been supported by NSF Grant GB 3193.
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Murmanis, L., Evert, R.F. Parenchyma cells of secondary phloem in Pinus strobus . Planta 73, 301–318 (1967). https://doi.org/10.1007/BF00385376
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DOI: https://doi.org/10.1007/BF00385376