The hypothesis that flower maintenance requires resources that would be used to support other plant functions (i.e. a cost of floral maintenance) was tested by experimentally manipulating floral longevity. Plants of Clarkia tembloriensis, a species with pollination-induced flower senescence, received either early or late pollinations (long and short longevities, respectively). We examined the effect of this manipulation on (1) per-flower allocation to nectar production and (2) flower, fruit and seed production per plant under two levels of resource availability. The direct costs of floral longevity measured in terms of nectar sugar were high: flowers that were maintained 35% longer invested proportionately more in nectar sugar (30%). At the whole-plant level, a cost of floral longevity was manifested as reduced seed production, but the magnitude of this cost varied with resource level. While plants with longer-lived flowers showed a 12% reduction in seed production, those that experienced reduced resource levels via partial defoliation, showed a decrement in seed production that was almost three times larger (34%). These differences were not brought about by changes in the number of flowers and fruits, but by significant alterations in their sizes. A model that expresses the cost of flower maintenance as a trade-off between floral longevity and seed production shows that an optimal flower longevity is determined by both the rate of fitness accrual and the cost of floral maintenance.
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Ascher, P.D. and Peloquin, S.J. (1966) Effect of floral aging on the growth of compatible and incompatible pollen tubes in Lilium longiflorum. Am. J. Bot. 53, 99–102.
Ashman, T.-L. (1992) Indirect costs of seed production within and between seasons in a gynodioecious species. Oecologia 92, 266–272.
Ashman, T.-L. and Schoen, D.J. (1994) How long should flowers live? Nature 371, 788–791.
Ashman, T.-L. and Schoen, D.J. (1996) Floral longevity: Fitness consequences and resource costs. In Floral Biology: Studies on Floral Evolution in Animal-pollinated Plants (D.G. Lloyd and S.C.H. Barrett, eds), pp. 112–139. Chapman and Hall, New York.
Bateman, A.J. (1948) Intrasexual selection in Drosophila. Heredity 2, 349–368.
Bazzaz, F.A. and Carlson, R.W. (1979) Photosynthetic contribution of flowers and seeds to reproductive effort of an annual colonizer. New Phytologist 82, 223–232.
Bookman, S.S. (1983) Effects of pollination timing on fruiting in Ascelpias speciosa Torr. (Asclepiadaceae). Am. J. Bot. 70, 897–905
Burd, M. and Head, G. (1992) Phenological aspects of male and female function in hermaphrodite plants. Am. Nat. 140, 305–324.
Chapin, F.S., III (1989) The cost of tundra plant structures: Evaluation of concepts and currencies. Am. Nat. 133, 1–19.
Charnov, E.L. (1982) The Theory of Sex Allocation. Princeton University Press, Princeton, NJ.
Colosi, J.C. and Cavers, P.B. (1984) Pollination affects percent biomass allocated to reproduction in Silene vulgaris (bladder campion). Am. Nat. 124, 299–306.
Delph, L.F. (1990) Sex-differential resource allocation patterns in the subdioecious shrub Hebe subalpina. Ecology 71, 1342–1351.
Galen, C., Shykoff, J.A. and Plowright, R.C. (1986) Consequences of stigma receptivity schedules for sexual selection in flowering plants. Am. Nat. 127, 462–476.
Galen, C., Dawson, T.E. and Stanton, M.L. (1993) Carpels as leaves: Meeting the carbon cost of reproduction in an alpine buttercup. Oecologia 95, 187–193.
Geber, M.A. and Charnov, E.L. (1986) Sex allocation with partial overlap in male/female resource inputs. J. Theor. Biol. 118, 33–43.
Gifford, R.M. and Evans, L.T. (1981) Photosynthesis, carbon partitioning and yield. Ann. Rev. Plant Physiol. 32, 485–509.
Gori, D.F. (1983) Post-pollination phenomena and adaptive floral changes. In Handbook of Experimental Pollination Biology (C.E. Jones and R.J. Little, eds), pp. 31–49. Van Nostrand Reinhold, New York.
Hanson, C.H. (1961) Longevity of pollen and ovaries in Alfalfa. Crop Sci. 1, 114–116.
Harder, L.D. and Barrett, S.C.H. (1992) The energy cost of bee pollination for Pontederia cordata (Pontederiaceae). Func. Ecol. 6, 226–233.
Harder, L.D. and Thomson, J.D. (1989) Evolutionary options for maximizing pollen dispersal of animal pollinated plants. Am. Nat. 133, 323–344.
Holtsford, T.P. (1985) Nonfruiting hermaphroditic flowers of Calochortus leichtlinii (Liliiaceae): Potential reproductive functions. Am. J. Bot. 72, 1687–1694.
Holtsford, T.P. (1989) Genetic causes and consequences of variation in the mating system of Clarkia tembloriensis (Onagraceae). PhD dissertation, University of California, Riverside.
Holtsford, T.P. and Ellstrand, N.C. (1992) Genetic and environmental variation in floral traits affecting outcrossing rate in Clarkia tembloriensis (Onagraceae). Evolution 26, 216–225.
Horvitz, C.C. and Schemske, D.W. (1988) Demographic cost of reproduction in a neotropical herb: An experimental field study. Ecology 69, 1741–1745.
Jackson, L.L. and Dewald, C.L. (1994) Predicting evolutionary consequences of greater reproductive effort in Tripsacum dactyloides, a perennial grass. Ecology 75, 627–641.
Lehtilä, K. and Syrjänen, K. (1995) Positive effects of pollination on subsequent size, reproduction and survival of Primula veris. Ecology 76, 1084–1098.
Lloyd, D.G. and Bawa, K.S. (1984) Modification of the gender of seed plants in varying conditions. Evol. Biol. 17, 225–338.
Lloyd, D.G. and Webb, C.J. (1986) The avoidance of interference between the presentation of pollen and stigmas in angiosperms. I. Dichogamy. NZ J. Bot. 24, 135–162.
Lloyd, D.G. and Yates, J.M.A. (1982) Intersexual selection and the segregation of pollen and stigmas in hermaphroditic plants, exemplified by Wahlenbergia albomarghinata (Campanulaceae). Evolution 36, 903–915.
Lubbers, A.E. and Lechowicz, M.J. (1989) Effects of leaf removal on reproduction vs below ground storage in Trillium grandiflorum. Ecology 70, 85–96.
McKenna, M.A. and Thomson, J. (1988) A technique for sampling and measuring small amounts of floral nectar. Ecology 69, 1306–1307.
Molau, U., Calsson, M., Dahlberg, A. and Hill, Ö. (1989) Mating system and pollen-mediated gene flow in Bartsia alpina. Oikos 55, 409–419.
Morgan, M. (1993) Fruit to flower ratios and trade-offs in size and number. Evol. Ecol. 7, 219–232.
Morse, D.H. (1987) Roles of polen and ovary age in follicle production of the common milkweed Asclepias syriaca. Am. J. Bot. 74, 851–856.
Nobel, P.S. (1977) Water relations of flowering in Agave deserti. Bot. Gazette 138, 1–6.
Palmer, M., Travis, J. and Antonovics, J. (1989) Temporal mechanisms influencing gender expression and pollen flow within a self-incompatible perennial, Amianthium muscaetoxicum (Liliaceae). Oecologia 78, 231–236.
Primack, R.B. (1985) Longevity of individual flowers. Ann. Rev. Ecol. Syst. 16, 15–37.
Pyke, G.H. (1991) What does it cost a plant to produce floral nectar? Nature 350, 58–59.
Reekie, E.G. (1991) Cost of seed versus rhizome production in Agropyron repens. Can. J. Bot. 69, 2678–2683.
Schoen, D.J. and Ashman, T.-L. (1995) The evolution of floral longevity: Resource allocation to maintenance versus construction of repeated structures in modular organisms. Evolution 49, 131–139.
Schoen, D.J. and Dubuc, M. (1990) The evolution of inflorescence size and number: A gamete-packaging strategy in plants. Am. Nat. 135, 841–857.
Shaw, R.F. and Mohler, J.D. (1953) The selective significance of the sex ratio. Am. Nat. 87, 337–342.
Silvertown, J. (1987) The evolution of hermaphroditism: An experimental test of the resource model. Oecologia 72, 157–159.
Smith-Huerta, N.L. and Vasek, F.C. (1984) Pollen longevity and stigma pre-emption in Clarkia. Am. J. Bot. 71, 1183–1191.
Southwick, E.E. (1984) Photosynthate allocation to floral nectar: A neglected energy investment. Ecology 65, 1775–1779.
Stanton, M.L., Bereczky, J.K. and Hasbrouck, H.D. (1987) Pollination thoroughness and maternal yield regulation in wild radish, Raphanus raphanistrum (Brassicaeae). Oecologia 74, 68–76.
Thomson, J.D. and Barrett, S.C.H. (1981) Selection for outcrossing, sexual selection and the evolution of dioecy in plants. Am. Nat. 118, 443–449.
Thomson, J.D. and Thomson, B.A. (1992) Pollen presentation and viability schedules in animal-pollinated plants: Consequences for reproductive success. In Ecology and Evolution of Plant Reproduction: New Approaches (R. Wyatt, ed.), pp. 1–24. Chapman and Hall, New York.
Thomson, J.D., Rigney, L.P., Karoly, K.M. and Thomson, B.A. (1994) Pollen viability, vigor, and competitive ability in Erythronium grandiflorum (Liliaceae). Am. J. Bot. 81, 1257–1266.
Tuomi, J., Hakala, T. and Haukioja, E. (1983) Alternative concepts of reproductive effort, cost of reproduction, and selection in life-history evolution. Am. Zool. 23, 25–34.
Willson, M.F. and Burley, N. (1983) Mate Choice in Plants. Princeton University Press, Princeton, NJ.
Vasek, F.C. and Weng, V. (1988) Breeding systems of Clarkia sect. Phaeostoma (Onagraceae): I. Pollen-ovule ratios. Syst. Bot. 13, 336–350.
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Ashman, TL., Schoen, D.J. The cost of floral longevity in Clarkia tembloriensis: An experimental investigation. Evolutionary Ecology 11, 289–300 (1997). https://doi.org/10.1023/A:1018416403530
- cost of reproduction
- floral longevity
- life-history trade-off
- resource allocation