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Trichomes and stomata, and their taxonomic significance in theUrticales


Structure and ontogeny of stomata and trichomes have been studied in 23 species and 3 varieties of theUrticales. Stomata are anomocytic, more rarely paracytic; anisocytic and sometimes helicocytic and transitorial types are found inUrticaceae andDorstenia, rarely inArtocarpus. The ontogeny of anomocytic and actinocytic stomata is perigenous, of paracytic either mesogenous or perigenous, of anisocytic either mesogenous or mesoperigenous, and of helicocytic and transitional types mesogenous. Among trichomes eglandular unicellular (wide spread), bicellular or uniseriate filiform (Cannabis); glandular capitate with uni- or bicellular (Moraceae, Ulmaceae, Cannabaceae), uniseriate filiform (Ulmaceae) or multiseriate stalk (Cannabis); sunken glands (Artocarpus); uniseriate glandular with uniseriate stalk (Celtis), and stinging emergences (Urticaceae) have been observed. It is concluded that theUrticales represent a natural order with four families:Ulmaceae, Moraceae, Urticaceae andCannabaceae which are distinct but interrelated with each other.

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  1. Bentham, G., andHooker, J. D., 1880: Genera plantarum.3/1, 341–395. London: L. Reeve & Co., Williams & Norgate. — Reprint by J. Cramer.

    Google Scholar 

  2. Dayanandan, P., andKaufman, P. B., 1976: Trichomes ofCannabis sativa L. (Cannabaceae). Amer. J. Bot.63, 578–591.

    Google Scholar 

  3. Engler, A., 1889:Urticaceae, Moraceae, Ulmaceae. InEngler, A., undPrantl, K., (Eds.): Die natürlichen Pflanzenfamilien III/1, 59–118. Leipzig: W. Engelmann.

    Google Scholar 

  4. Hammond, C. T., andMahlberg, P. G., 1973: Morphology of glandular hairs ofCannabis sativa from scanning electron microscopy. Amer. J. Bot.60, 524–528.

    Google Scholar 

  5. Husson, P., 1968: Etude de l'appareil stomatique chez la plantule d'Urtica membranacea Poir. Bull. Soc. Hist. Nat. Toul.104, 125–130.

    Google Scholar 

  6. - 1969: Stomates et cellules annexes chez lesProcrideae. Ibid.105, 265–269.

  7. Mehra, P. N., andGill, B. S., 1974: Cytological studies inUlmaceae, Moraceae andUrticaceae. J. Arnold Arb.55, 663–675.

    Google Scholar 

  8. Metcalfe, C. R., andChalk, L., 1950: Anatomy of Dicotyledons. Vol. 2. Oxford, London: Clarendon Press.

    Google Scholar 

  9. Payne, W. W., 1970: Helicocytic and allelocytic stomata: Unrecognised patterns in the dicotyledons. Amer. J. Bot.57, 140–147.

    Google Scholar 

  10. Shah, A. M., andKachroo, P., 1975: Comparative anatomy inUrticales I. The trichomes inMoraceae. J. Ind. Bot. Soc.54, 138–153.

    Google Scholar 

  11. Solereder, H., 1880: Systematic Anatomy of Dicotyledons. Vol. 2. Oxford, London: Clarendon Press.

    Google Scholar 

  12. Takhtajan, A., 1966: Flowering Plants: Origin and Dispersal. Washington: Smithsonian Institution Press.

    Google Scholar 

  13. Thurston, E. L., 1974: Morphology, fine structure, and ontogeny of the stinging emergence ofUrtica dioica. Amer. J. Bot.61, 809–817.

    Google Scholar 

  14. —, andLersten, N. R., 1969: The morphology and toxicology of plant stinging hairs. Bot. Rev.35, 393–412.

    Google Scholar 

  15. Uphof, J. C. Th. 1962: Plant hairs. Handbuch der Pflanzenanatomie, 2. ed.,IV/5, 1–206. Berlin-Nikolassee: Gebr. Borntraeger.

    Google Scholar 

  16. Weiss, A., 1867: Die Pflanzenhaare. InKarsten, H. (Ed.): Botanische Untersuchungen aus dem Physiologischen Laboratorium der Landwirthschaftlichen Lehranstalt, Berlin,1, 369–677.

  17. Willis, J. C., 1966: A Dictionary of Flowering Plants and Ferns. Cambridge: The University Press.

    Google Scholar 

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Gangadhara, M., Inamdar, J.A. Trichomes and stomata, and their taxonomic significance in theUrticales . Pl Syst Evol 127, 121–137 (1977).

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Key words

  • Urticales
  • Ulmaceae
  • Moraceae
  • Urticaceae
  • Systematic anatomy
  • trichomes
  • stomata