Abstract
Vaccinium meridionale is a wild plant producing edible fruits in the mountain areas of Northern South America. However, the fruits of this species has been under an unsustainable extraction and there is a growing interest of establishing this species as a crop; nevertheless, the information about its breeding system is scarce, which is essential for its sustainable management and conservation. This research aimed to study the floral and reproductive biology of V. meridionale in natural conditions, and to analyze the importance of pollinators on its reproduction, in two wild populations of V. meridionale in the states of Cundinamarca and Boyacá, in the Oriental Cordillera of Colombia. For this, we have made different observations and experiments to describe its flower morphology, floral phenology, pollen viability, stigma receptivity, pollen-ovule ratio and nectar production. To study its reproductive system, we performed experiments of flower emasculation, pollinator exclusion and hand pollination (self-and cross-pollination). We found that although the flowers have poricidal anthers, the release of pollen could occur easily without vibration. V. meridionale shows a large floral display, long floral longevity and has female-biased nectar production. The pollen-ovule ratio was of 571±133, which classified the species as facultative xenogamy. This result agreed with the pollination experiments because the plants produced fruits by agamospermy, selfing and outcrossing. However, we registered a strong inbreeding depression, observed in high rates of fruit abortions, after self-pollination. Unlike of self-pollinating fruits, the plant retains those produced by cross-pollination since its formation. The floral traits showed by this species are mechanisms to favor a more diverse guild of floral visitors than only insects able to buzz-pollination. In addition, these floral traits may enhance the pollination probability, and reduce geitonogamy. Moreover, the inbreeding depression suggests that V. meridionale promotes outcrossing as its main reproductive strategy. Therefore, pollinators, particularly bees, are essential for this species reproduction and conservation, and are critical in the maintenance of its genetic variability and fruits production.
References
Ashman, T. L. (2006). The evolution of separate sexes: a focus on the ecological context. In L. D. Harder & S. C. H. Barrett (Eds.), Ecology and evolution of flowers (pp. 204-222). Oxford: Oxford University Press.
Barrett, S. C. H. (2002). Sexual interference of the floral kind. Heredity, 88, 154-159.
Bell, D. J., Drummond, F. A., & Rowland, L. J. (2012). Evidence of functional gender polymorphisms in a population of the hermaphroditic lowbush blueberry (Vaccinium angustifolium). Botany, 90, 393-399.
Brevis, P. A. (2005). Factors controlling fruit set of rabbiteye blueberry (Vaccinium ashei Reade) (PhD. dissertation). University of Georgia, Athens, U.S.A.
Cane, J. H., Eickwort, G. C., Wesley, F. R., & Spielholz, J. (1985). Pollination Ecology of Vaccinium stamineum (Ericaceae: Vaccinioideae). American Journal of Botany, 72(1), 135-142.
Carlson, J. E., & Harms, K. E. (2006). The Evolution of Gender-Biased Nectar Production in Hermaphroditic Plants. The Botanical Review, 72(2), 179-205.
Castro, C., Olarte, Y., Rache, L., & Pacheco, J. (2012). Development of a germination protocol for blueberry seeds (Vaccinium meridionale Swartz). Agronomía Colombiana, 30(2), 196-203.
Chamorro, F. (2014). Influencia de la polinización por abejas sobre la producción y características de frutos y semillas de Vaccinium meridionale Sw. (Ericaceae) en los Andes Orientales de Colombia (Tesis de Maestría). Universidad Nacional de Colombia, Bogotá, D.C., Colombia.
Charlesworth, D., & Charlesworth, B. (1987). Inbreeding Depression and its Evolutionary Consequences. Annual Review of Ecology and Systematics, 18, 237-268.
Charlesworth, B., & Charlesworth, D. (1978). A model for the evolution of dioecy and gynodioecy. The American Naturalist, 112(988), 975-997.
Cruden, R. W. (1977). Pollen-Ovule Ratios: A Conservative Indicator of Breeding Systems in Flowering Plants. Evolution, 31(1), 32-46.
Dafni, A., Pacini, E., & Nepi, M. (2005). Pollen and stigma biology. In A. Dafni, P. G. Kevan, & B. C. Husband (Eds.), Practical Pollination Ecology (pp. 83-145). Cambridge: Enviroquest Ltd.
Delph, L. F., Lively, C. M., & Webb, C. J. (2006). Gynodioecy in native New Zealand Gaultheria (Ericaceae). New Zealand Journal of Botany, 44(4), 415-420.
Galetto, L., & Bernardello, G. (2005). Rewards in flowers: Nectar. In A. Dafni, P. G. Kevan, & B.C. Husband (Eds.), Practical pollination ecology (pp. 261-313). Cambridge: Enviroquest Ltd.
Gupton, C. L., & Spiers, J. M. (1994). Interspecific and Intraspecific Pollination Effects in Rabbiteye and Southern Highbush Blueberry. Hort Science, 29(4), 324-326.
Hagerup, O. (1954). Autogamy in some drooping bicornes flowers. Botanisk Tidesskrift, 51, 103-116.
Harder, L. D., & Barrett, S. C. H. (1995) Mating cost of large floral displays in hermaphrodite plants. Nature, 373(9), 512-515.
Heinrich, B. (1975). Energetics of Pollination. Annual Review of Ecology and Systematics, 6, 139-170.
Howard, A. F., & Barrows, E. M. (2014). Self-pollination rate and floral-display size in Asclepias syriaca (Common Milkweed) with regard to floral-visitor taxa. BMC Evolutionary Biology, 14, 144. doi:10.1186/1471-2148-14-144.
Jacquemart, A. L., & Thompson, J. D. (1996). Floral and pollination biology of three sympatric Vaccinium (Ericaceae) species in the Upper Ardenne, Belgium. Canadian Journal of Botany, 74, 210-221.
Jacquemart, A. L. (2003). Floral traits of belgian ericaceae species: are they good indicators to assess the breeding systems? Belgian Journal of Botany, 136(2), 154-164.
Lande, R., & Schemske, D. W. (1985). The evolution of self-fertilization and inbreeding depression in plants. I. Genetic Models. Evolution, 39(1), 24-40.
Lang, G. A., & Danka, R. G. (1991). Honey-bee-mediated Cross-versus Self-pollination of ‘Sharpblue’ Blueberry Increases Fruit Size and Hastens Ripening. Journal of the American Society for Horticultural Science, 116(5), 770-773.
Larson, B. M. H., & Barrett, S. C. H. (1999). The pollination ecology of buzz-pollinated Rhexia virginica (Melastomataceae). American Journal of Botany, 86(4), 502-511.
Ligarreto, G. A. (Ed.). (2009). Perspectivas del cultivo de agraz o mortiño (Vaccinium meridionale Swartz) en la zona altoandina de Colombia. Bogotá: Facultad de Agronomía, Universidad Nacional de Colombia.
Ligarreto, G. E., Patiño, M. P., & Magnitskiy, S. (2011). Phenotypic plasticity of Vaccinium meridionale (Ericaceae) in wild populations of mountain forests in Colombia. Revista de Biología Tropical, 59(2), 569-583.
Lloyd, D. G., & Schoen, D. J. (1992). Self- and Cross-Fertilization in Plants. l. Functional Dimensions. International Journal of Plant Sciences, 153(3-Part 1), 358-369.
Luteyn, J. (2002). Diversity, adaptation, and endemism in neotropical Ericaceae: Biogeographical patterns in the Vaccinieae. The Botanical Review, 68(1), 55-87.
MacKenzie, K. (1997). Pollination requirements of three varieties of highbush blueberry (Vaccinium corymbosum L.). Journal of the American Society for Horticultural Science, 122(6), 891-896.
MacKenzie, K. (2009). Pollination Practices and the Use of Bees in Vaccinium Crops. Acta Horticulturae, 810, 527-538.
Mandujano-Sánchez, M. C. (2007). La clonalidad y sus efectos en la biología de poblaciones. In L. E. Eguiarte, V. Souza, & X. Aguirre (Eds.), Ecología Molecular (pp. 215-250). México, D.F.: Secretaría de Medio Ambiente y Recursos Naturales, Instituto Nacional de Ecología, Universidad Nacional Autónoma de México, Comisión Nacional para el Conocimiento y Uso de la Biodiversidad.
Martin, F. W. (1959). Staining and observing pollen tubes by means of fluorescence. Stain Technology, 34, 125-128.
Medina, C. I., Lobo, M., Patiño, M. P., Ligarreto, G. A., Delgado, O. A., Lopera, S. A., & Toro, J. L. (2009). In G. A. Ligarreto (Ed.), Perspectivas del cultivo de agraz o mortiño (Vaccinium meridionale Swartz) en la zona altoandina de Colombia (pp. 57-74). Bogotá: Facultad de Agronomía, Universidad Nacional de Colombia.
Middleton, D. J. (1991). Ecology, reproductive biology and hybridization in Gaultheria L. Edinburgh Journal of Botany, 48, 81-89.
Mitchell, R. J., Karron, J. D., Holmquist, K. G., & Bell, J. M. (2004). The influence of Mimulus ringens floral display size on pollinator visitation patterns. Functional Ecology, 18, 116-124.
Myra, M., MacKenzie, K., & Vander Kloet, S. P. (2004). Investigation of a possible sexual function specialization in the lowbush blueberry (Vaccinium angustifolium Ait. Ericaceae). Small Fruits Review, 3(3-4), 313-324.
Nestby, R., Percival, D., Martinussen, I., Opstad, N., & Rohloff, J. (2011). The European blueberry (Vaccinium myrtillus) and the potential for cultivation. A review. The European Journal of Plant Science and Biotechnology, 5(Special Issue I), 5-16.
Nuortila, C., Tuomi, J., Aspi, J., & Laine, K. (2006). Early-acting inbreeding depression in a clonal dwarf shrub, Vaccinium myrtillus, in a northern boreal forest. Annales Botanici Fennici, 43, 36-48.
Ohara, M., & Shimamoto, Y. (2002). Importance of genetic characterization and conservation of plant genetic resources: the breeding system and genetic diversity of wild soybean (Glycine soja). Plant Species Biology, 17, 51-58.
Pedraza-Peñalosa, P., & Luteyn, J. L. (2011). Andean Vaccinium (Ericaceae: Vaccinieae): Seven new species from South America. Brittonia, 63(2), 257-275.
Pinilla, M. S. (2013). Visitantes florales y polinizadores potenciales del agraz (Vaccinium meridionale) en Cundinamarca y Boyacá (Trabajo de grado). Universidad Militar Nueva Granada, Bogotá, D.C., Colombia.
Ramírez, M. M., & Ornelas, J. F. (2010). Pollination and nectar production of Psittacanthus schiedeanus (Loranthaceae) in central Veracruz, México. Boletín de la Sociedad Botánica de México, 87, 61-67.
Rathcke, B. J. (2003). Floral longevity and reproductive assurance: seasonal patterns and an experimental test with Kalmia latifolia (Ericaceae). American Journal of Botany, 90(9), 1328-1332.
Richards, A. J. (2003). Apomixis in flowering plants: an overview. Philosophical Transactions of Royal Society B Biological Sciences, 358(1434), 1085-1093.
Siegel, S., & Castellan, N. J. (1988) Stephens. Nonparametric statistics for the behavioral sciences. New York: McGraw-Hill.
Statsoft Inc. (2011). Statistica (versión 10 para Windows). Tulsa, Oklahoma: Statsoft Inc.
Stephens, D. T., Levesque, D. E., & Davis, A. R. (2012). Pollen-ovule ratios in seven species of Vaccinium (Ericaceae) and stamen structure in Vaccinium myrtilloides and Vaccinium vitis-idaea. Botany, 90, 599-614.
Stephenson, A. G. (1981). Flower and fruit abortion: proximate causes and ultimate functions. Annual Review of Ecology and Systematics, 12, 253-279.
Tanner, E. V. J. (1982). Species diversity and reproductive mechanisms in Jamaican trees. Biological Journal of the Linnean Society, 18(3), 263-278.
Torres-Díaz, C., Gómez-González, S., Stotz, G. C., Torres-Morales, P., Paredes, B., Pérez-Millaqueo, M., & Gianoli, E. (2011). Extremely Long-Lived Stigmas Allow Extended Cross-Pollination Opportunities in a High Andean Plant. PlosONE, 6(5), e19497. doi:10.1371/journal.pone.0019497.
Usui, M., Kevan, P. G., & Obbard, M. (2005). Pollination and Breeding System of Lowbush Blueberries, Vaccinium angustifolium Ait. and V. Myrtilloides Michx. (Ericacaeae), in the Boreal Forest. The Canadian Field-Naturalist, 119(1), 48-57.
Valencia, M. L. C., & Ramírez, F. (1993). Notas sobre la morfología, anatomía y germinación del Agraz (Vaccinium meridionale Swartz.). Agronomía Colombiana, 10, 151-159.
Comments
This work is licensed under a Creative Commons Attribution 4.0 International License.
Copyright (c) 2015 Revista de Biología Tropical