Characterization of sugar diversity in floral and extra-floral nectar from the Coastal Coral Tree (Erythrina caffra Thunb.) in Southern California

Abstract

The Coastal Coral Tree (Erythrina caffra Thunb.) produces floral nectar (FN) that serves to attract pollinating insects, but also secretes nectar from extra-floral (EFN) glands that serves to attract predatory insects, such as ants. While studies on myrmecophytes (i.e. specialized plants that attract and interact with ants) have primarily focused on interspecific evaluations of EFN chemistry, the Coastal Coral tree offers an opportunity to contrast intraspecific nectar chemistry with differing evolutionary and ecological functions. We hypothesized that the richness of (molecular) sugar species, relative concentrations, and diversity of sugars in FN and foliar EFN would diverge due to differences in the ecological role of the two types of nectar. High performance liquid chromatography with refractive index detection was used to identify the richness of sugar species (based on retention time), measure the relative concentrations, and evaluate the diversity of sugars in FN and foliar EFN secretions. We detected sugar species unique to each gland type and reported significant differences in the relative concentration of one sugar species common to both gland types. While the mean diversity index of sugars was similar for both gland types, the diversity of foliar EFN sugars was significantly more variable than that of FN sugars. The composition of FN showed little variation, and was reflective of its fundamental role in plant reproduction. Foliar EFN, however, demonstrated the variability expected of a context-dependent myrmecophyte that interacts with a facultative ant species assemblage across a mosaic of abiotic and biotic conditions.

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Carmona-Galindo, V. , Morales, K. , Maser, R. , Doyle, J. and Gobrial, M. (2014) Characterization of sugar diversity in floral and extra-floral nectar from the Coastal Coral Tree (Erythrina caffra Thunb.) in Southern California. Open Journal of Ecology, 4, 23-27. doi: 10.4236/oje.2014.42003.

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1] Holldobler, B. and Wilson, E.O. (1990) The ants. Belknap Press of Harvard University Press, Cambridge.
[2] Cuautle, M. and Rico-Gray, V. (2003) The effect of wasps and ants on the reproductive success of the extrafloral nectaried plant Turnera ulmifolia (Turneraceae). Functional Ecology, 17, 417-423.
http://dx.doi.org/10.1046/j.1365-2435.2003.00732.x
[3] Beattie, A.J. (1985) The evolutionary ecology of ant-plant mutualisms. Cambridge University Press, Cambridge.
[4] Ness, J.H., Bronstein, J.L., Andersen, A.N. and Holland, J.N. (2004) Ant body size predicts dispersal distance of ant-adapted seeds: Implications of small-ant invasions. Ecology, 85, 1244-1250.
http://dx.doi.org/10.1890/03-0364
[5] Sagers, C.L., Ginger, S.M. and Evans, R.D. (2000) Carbon and nitrogen isotopes trace nutrient exchange in an ant-plant mutualism. Oecologia, 123, 582-586.
http://dx.doi.org/10.1007/PL00008863
[6] Coley, P.D., Lokvam, J., Rudolph, K., Bromberg, K., Sackett, T.E., Wright, L., Brenes-Arguedas, T., Dvorett, D., Ring, S., Clark, A., Baptiste, C., Pennington, T. and Kursar, T.A. (2005) Divergent defensive strategies of young leaves in two species of Inga. Ecology, 86, 2633-2643.
http://dx.doi.org/10.1890/04-1283
[7] Heil, M., Rattke, J. and Boland, W. (2005) Postsecretory hydrolysis of nectar sucrose and specialization in ant/ plant mutualism. Science, 308, 560-563.
http://dx.doi.org/10.1126/science.1107536
[8] Heil, M., Baumann, B., Krüger, R. and Linsenmair, K.E. (2004) Main nutrient compounds in food bodies of Mexican Acacia ant-plants. Chemoecology, 14, 45-52.
http://dx.doi.org/10.1007/s00049-003-0257-x
[9] Michelangeli, F.A. (2003) Ant protection against herbivory in three species of Tococa (Melastomataceae) occupying different environments. Biotropica, 35, 181-188.
http://dx.doi.org/10.1646/01509
[10] Thunberg, C.P. (1800) Prodromus plantarum Capensium: quas in promontorio Bonae Spei Africes. Upsaliae: J. Edman, Cape Town.
[11] National Research Council (U.S.) Advisory Committee on Technology Innovation (1979) Tropical legumes: Resources for the future: Report of an ad hoc panel of the Advisory Committee on Technology Innovation, Board on Science and Technology for International Development, Commission on International Relations, National Research Council. National Academies, Washington, 258.
[12] Sherbrooke, W.C. and Scheerens, J.C. (1979) Ant-visited extrafloral (calyx and foliar) nectaries and nectar sugars of Erythrina flabelliformis Kearney in Arizona. Annals of the Missouri Botanical Garden, 66, 472-481.
http://dx.doi.org/10.2307/2398839
[13] Baker, H.G. (1975) Sugar concentrations in nectars from hummingbird flowers. Biotropica, 7, 37-41.
http://dx.doi.org/10.2307/2989798
[14] Vitali-Veiga, M.J. and Machado, V.L.L. (2000) Flowering visitors of Erythrina speciosa Andr., Leguminosae. Revista Brasileira de Zoologia, 17, 369-383.
http://dx.doi.org/10.1590/S0101-81752000000200007.
[15] Rico-Gray, V. and Oliveira, P.S. (2007) The ecology and evolution of ant-plant interactions. University of Chicago Press, Chicago.
[16] Bory, G. and, Clair-Maczulajtys, D. (1986) Composition of nectar and role of extrafloral nectars in Ailanthus glandulosa. Canadian Journal of Botany, 64, 247-253.
[17] Bory, G. and Clair-Maczulajtys, D. (1990) Importance of foliar nectaries in the physiology of tree of heaven Ailanthus glandulosa Desf. Simaroubaceae. Bulletin de la Societe Botanique de France Lettres Botaniques, 137, 139156.
[18] Becerra, J.X. and Venable, D.L. (1989) Extrafloral nectaries: A defense against ant-Homoptera mutualisms? Oikos, 55, 276-280. http://dx.doi.org/10.2307/3565432
[19] Kerner, A. (1878) Flowers and their unbidden guests. C. Kegan Paul & Co., London.
[20] Wagner, D. and Kay, A. (2002) Do extrafloral nectaries distract ants from visiting flowers? An experimental test of an overlooked hypothesis. Evolutionary Ecology Research, 4, 293-305.
[21] Boucher, D.H. (1988) The biology of mutualism: Ecology and evolution. Oxford University Press, New York.
[22] Shannon, C.E. (1948) A mathematical theory of communication. The Bell System Technical Journal, 27, 379-423.
[23] Bluthgen, N., Gottsberger, G. and Fiedler, K. (2004) Sugar and amino acid composition of ant-attended nectar and honeydew sources from an Australian rainforest. Austral Ecology, 29, 418-429.
http://dx.doi.org/10.1111/j.1442-9993.2004.01380.x
[24] Del Claro, K. and Oliveira, P.S. (1993) Ant-homoptera interaction: Do alternative sugar sources distract tending ants? Oikos, 68, 202-206.
http://dx.doi.org/10.2307/3544831
[25] van Wyk, B.E. (1993) Nectar sugar composition in southern African Papilionoideae (Fabaceae). Biochemical Systematics and Ecology, 21, 271-277.
http://dx.doi.org/10.1016/0305-1978(93)90045-S
[26] Southwood, T.R.E., Moran, V.C. and Kennedy, C.E.J. (1982) The richness, abundance and biomass of the arthropod communities on trees. The Journal of Animal Ecology, 51, 635-649. http://dx.doi.org/10.2307/3988
[27] Bronstein, J.L. (1994) Conditional outcomes in mutualistic interactions. Trends in Ecology & Evolution, 9, 214-217. http://dx.doi.org/10.1016/0169-5347(94)90246-1
[28] Janzen, D.H. (1973) Dissolution of mutualism between Cecropia and its Azteca ants. Biotropica, 5, 15-28.
http://dx.doi.org/10.2307/2989677
[29] Putz, F. and Holbrook, N. (1988) Further observations on the dissolution of mutualism between Cecropia and its ants: the Malaysian case. Oikos, 53, 121-125.
http://dx.doi.org/10.2307/3565671.

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