Abstract
Dendrocacalia crepidifolia Nakai (Compositae, Senecioneae), the only species of this arboreal genus endemic to Haha Island in the Bonin Islands, was found to be dioecious. Male flowers differ from female ones in having a stunted style (style in female exserted from corolla and deeply bifurcating) and anthers filled with fertile pollen (anthers in the female lacking pollen). The size of the corolla and number of florets per head were similar between male and female flowers. The crown area of this arboreal species was also similar in male and female plants. The sex ratio was 0.55 male, not significantly different from 0.5. Both sexes produced nectar of similar sugar concentration (ca. 50%). The flowers are pollinated by feral honeybees (Apis mellifera), but they are thought to have been pollinated by small, lesshairy, endemic solitary bees before honeybees were introduced and subsequently became the dominant bee species on the island. The evolution of dioecy ofDendrocacalia on the island is thought to stem from the deleterious effects of inbreeding that are inherent in plants with geitonogamy. The increased geitonogamy on the island has resulted from increased woodiness (i.e., increased number of flowers per plant) and the original dependence on endemic bee pollinators, which are now endangered.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
Baker, H.G. 1959. Reproductive methods as factors in speciation in flowering plants. Cold Spring Harbor Symposia on Quantitative Biology24: 177–191.
Bawa, K.S. 1980. Evolution of dioecy in flowering plants. Ann. Rev. Ecol. Syst.11: 15–39.
Bawa, K.S. 1994. Pollinators of tropical dioecious angiosperms: A reassessment? No, not yet Amer. J. Bot.81: 456–460.
Bawa, K.S. andOpler, P.A. 1975. Dioecism in tropical forest trees. Evolution29: 167–179.
Bernhardt, P. 1987. A comparison of the diversity, density, and foraging behavior of bees and wasps on australianAcacia. Ann. Missouri Bot. Gard.74: 42–50.
Bremer, K. 1994. Asteraceae: Cladistics and Classification. Timber press, Portland, Oregon.
Carlquist, S. 1974. Island Biology. Columbia University Press, New York, NY.
Charlesworth, B. andCharlesworth, D. 1978. A model for the evolution of dioecy and gynodioecy. Am. Nat.112: 975–997.
Cuddihy, LW. andStone, C.P. 1990. Alteration of native Hawaiian vegetation: effects of humans, their activities and introductions. University of Hawaii Press, Honolulu, Hawaii.
de Jong, T.J., Waser, N.M., Price, M.V. andRing, R.M. 1992. Plant size, geitonogamy and seed set inIpomopsis aggregata. Oecologia89: 310–315.
de Jong, T.J., Waser, N.M. andL. Klinkhamer, P.G. 1993. Geitonogamy: the neglected side of selfing. Tr. Ecol. Evol.8: 321–325.
Erdtman, G. 1960. The acetolysis method. Svensk Botanisk Tidskrift54: 561–564.
Frankie, G., Opler, P.A. andBawa, K.S. 1976. Foraging behaviour of solitary bees: Implications for outcrossing of a neotropical forest tree species. J. Ecol.62: 881–919.
Funakoshi, M. 1990. Formation ofLeucaena glauca forests in the Bonin Islands. Ogasawara Kenkyû Nenpô14: 21–51. (in Japanese)
Galen, C., Gregory, T. andGalloway, L.F.. 1990. Costs of self-pollination in a self-incompatible plant,Polemonium viscosum. Amer. J. Bot.76: 1675–1680.
Godley, E.J. 1975. Flora and vegetation.In G. Kuschel, ed., Biogeography and Ecology in New Zealand, Junk, The Haque, pp. 177–229.
Helenurm, K. andGanders, F.R. 1985. Adaptive radiation and genetic differentiation in HawaiianBidens. Evolution39: 753–765.
Hessing, M.B. 1988. Geitonogamous pollination and its consequences inGeranium caespitosum. Amer. J. Bot.75: 1324–1333.
Hirashima, Y. 1989. A check List of Japanese Insects. Entomological Laboratory, Faculty of Agriculture. Kyushu University.
Howarth, F.G. andMull, W.P. 1992. Hawaiian Insects and Their Kin. University of Hawaii Press, Honolulu, Hawaii.
Ito, M. andOno, M. 1990. Allozyme diversity and the evolution ofCrepidiastrum (Compositae) on the Bonin (Ogasawara) Islands. Bot. Mag. Tokyo103: 449–459.
Kato, M. 1992. Endangered bee fauna and its floral hosts in the Ogasawara Islands. Jap. J. Entomol.60: 487–494.
Kawakubo, N. 1990. Dioecism of the genusCallicarpa (Verbenaceae) in the Bonin (Ogasawara) Islands. Bot. Mag. Tokyo103: 57–66.
Knox, R.B., Kenrick, J., Bernhardt, P., Marginson, R., Beresford, G. andBaker, H.G. 1985. Extra-floral nectaries as adaptations for bird pollination inAcacia terminalis. Amer. J. Bot.72: 1185–1196.
Messing, R.H. 1991. Status of beekeeping in the Hawaiian islands. Bee World72: 147–160.
Michener, C.D. 1974. The Social Behavior of the Bees: A Comparative Study. The Belknap Press. Cambridge.
Nagamasu, H. 1987. Notes onSymplocos lucida and related species in Japan. Acta Phytotax. Geobot.38: 283–291. (in Japanese)
Nakai, T. 1915. Plantae novae Japonicae et Koreanae IV. Bot. Mag. Tokyo29: 1–13.
Ono, M. 1975. Chromosome numbers of some endemic species of the Bonin Islands I. Bot. Mag. Tokyo88: 323–328.
Ono, M. 1985. Speciation and distribution ofPittosporum in the Bonin Islands,In H. Hara, ed., Evolution and Diversity in Plant and Communities. Academic Scientific Book, Tokyo, pp. 7–17.
Park, O.W. 1933. Studies on the changes in nectar concentration produced by the honeybee,Apis mellifera. Part I. Changes which occur between the flower and the hive. Iowa Agriculture and Home Economics Experiment Station Research Bulletin151: 211–243.
Perkins, R.C.L. 1901. Hymenoptera Aculeata. Fauna Hawaiiensis1: 1–115, Pls. 1–2.
Renner, S.S. andFeil, J.P. 1993. Pollinators of tropical dioecious angiosperms. Amer. J. Bot.80: 1100–1107.
Soejima, A., Nagamasu, H., Ito, M., andOno, M. 1994. Allozyme diversity and the evolution ofSymplocos (Symplocaceae) on the Bonin (Ogasawara) Islands. J. Plant Res.107: 221–227.
Strickler, K. 1979. Specialization and foraging efficiency of solitary bees. Ecology60: 998–1009.
Thomson, J.D. andBrunet, J. 1990. Hypotheses for the evolution of dioecy in seed plants. Tr. Ecol. Evol.5: 11–16.
Waser, N.M. andPrice, M.V. 1991. Reproductive costs of self-pollination inIpomopsis aggregata (Polemoniaceae): are ovules usurped? Amer. J. Bot.78: 1036–1043.
Webb, C.J. andKelly, D. 1993. The reproductive biology of the New Zealand flora. Tr. Ecol. Evol.8: 442–447.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Kato, M., Nagamasu, H. Dioecy in the endemic genusDendrocacalia (Compositae) on the Bonin (Ogasawara) Islands. J. Plant Res. 108, 443–450 (1995). https://doi.org/10.1007/BF02344232
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF02344232