The morphogenetic rôle of apical meristems: fundamental aspects (illustrated by means of the shoot apical meristem)
In all vascular plants, as in many non-vascular ones, the polarity of the new individual, with distinction of apex and base (or of distal and proximal regions respectively), is already established by the time the fertilised egg has undergone its first division, this being usually though not invariably by a transverse wall. The axial development thus has its inception at the outset of the ontogenesis, the apical pole being typically characterised by active protein synthesis, in contrast to the basal pole where the uptake and utilisation of osmotically active substances is a more evident feature1. The related histological developments include the formation of a distal region of densely protoplasmic, embryonic, or meristematic cells, which sooner or later become organized as the shoot apex, comprising the apical meristem and first leaf primordium or primordia, and a basal foot, or a suspensor, or both, the cells of which soon become enlarged, vacuolated and parenchymatous.
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- Running, E.: Morphogenesis in plants. Surv. biol. Progr. 2, 105–140 (1952).Google Scholar
- Reinhard, E.: Ein Vergleich zwischen diarchen und triarchen Wurzeln von Sinapis albs. Z. Bot. 44, 505–514 (1956).Google Scholar
- Richards, F. J.: The geometry of phyllotaxis and its origin. Symp. Soc. exp. Biol. 2, 217–245 (1948).Google Scholar
- Schoute, J. C.: Beiträge zur Blattstellungslehre. I. Die Theorie. Rec. Tray. bot. néerl. 10, 153–339 (1913).Google Scholar
- Schoute, J. C.: Fasciation and dichotomy. Rec. Tray. bot. néerl. 38, 649–669 (1936).Google Scholar
- Skooo, F.: Substances involved in normal growth and differentiation. Brookhaven Symp. Biol. 6, 1–21 (1954).Google Scholar
- SNow, M., and R. Sxow: On the determination of leaves. Symp. Soc. exp. Biol. 2, 263–275 (1948).Google Scholar
- Steward, F. C., R. H. Wetmore and J. K. Pollard: Nitrogenous compounds of the shoot apex of Adiantum pedatum. Amer. J. Bot. 42, 936–938 (1955).Google Scholar
- Thoday, D.: The interpretation of plant structure. Presidential Address, Sect. K, Brit. Ass. Advanc. Sci. 1939, 1–21.Google Scholar
- Wardlaw, C. W.: Phylogeny and morphogenesis. London: Macmillan 1952.Google Scholar
- Wardlaw, C. W.: Embryogenesis in plants. London: Methuen; New York: Wiley 1955 (c).Google Scholar
- Wetmore, R. H.: The use of in vitro cultures in the investigation of growth and differentiation in vascular plants. Brookhaven Symp. Biol. 6, 22–40 (1954).Google Scholar