Abstract
Electrophoretic methods are used to determine the genotype of individual pollinia simultaneously at several isozyme loci for the common milkweed, Asclepias syriaca. Isozymes of pollinia are the result of gene expression in pollen. Genotype frequencies of maternal plants, pollinia carried by honey bees and pollinia captured by flowers were determined and found to be comparable. Over 50% of bees carried genotypically mixed pollen loads. Methods for estimating the rate of self-pollination, assuming the mixed-pollination model, are developed and the rate of self-pollination in a population is found to be 66%. The use of the methods developed here for testing various hypotheses, including the operation of sexual selection in plant populations, is discussed.
Similar content being viewed by others
Article PDF
References
Bailey, N T J. (1961). Mathematical Theory of Genetic Linkage. Oxford University Press, London.
Barrett, S C H, and Wolfe, L M. 1986. Pollen heteromorphism as a tool in studies of the pollination process in Pontederia cordata L. In: Mulcahy, D. L., Bergamini Mulcahy, G, and Ottaviano, E. (eds) Biotechnology and Ecology of Pollen. Springer-Verlag, New York, pp. 435–442.
Beare, M H, and Perkins, W E. 1982. Effects of variation in floral morphology on pollination mechanisms in Asclepias tuberosa L., butterflyweed (Asclepiadaceae). Am J Bot, 69, 579–584.
Bookman, S S. 1984. Evidence for selective fruit production in Asclepias. Evolution, 38, 72–86.
Brown, A H D, Burdon, J J, and Jarosz, A M. 1989. Isozyme analysis of plant mating systems. In: Soltis, D. E, and Soltis, P. S. (eds) Isozymes in Plant Biology. Dioscorides Press, Portland Oregon, pp. 73–86.
Brown, A H D, Matheson, A C, and Eldridge, K G. 1975. Estimation of the mating system of Eucalyptus obliqua L'Herit by using allozyme polymorphisms. Australian J Bot, 25, 931–949.
Broyles, S B, and Wyatt, R. 1990. Paternity analysis in a natural population of Asclepias exaltata: multiple paternity, functional gender, and the “pollen donation hypothesis”. Evolution, 44, 1454–1468.
Broyles, S B, and Wyatt, R. 1991. Effective pollen dispersal in a natural population of Asclepias exaltata: the influence of pollinator behavior, genetic similarity, and mating success. Am Nat, 138, 1239–1249.
Clegg, M T. 1980. Measuring plant mating systems. Bioscience, 30, 814–818.
Ellstrand, N C, Devlin, B, and Marshall, D L. 1989. Gene flow by pollen into small populations: data from experimental and natural stands of wild radish. Proc Natl Acad Sci USA, 86, 9044–9047.
Ganders, F R. 1979. The biology of heterostyly. New Zealand J Bot, 17, 607–635.
Gay, G, Kerhoas, C, and Dumas, C. 1986. Micro-isoelectric focusing of pollen grain proteins in Cucurbita pepo, L. In: Mulcahy, D. L., Bergamini Mulcahy, G, and Ottaviano, E. (eds) Biotechnology and Ecology of Pollen. Springer-Verlag, New York, pp. 496–498.
Handel, S N. 1983. Pollination ecology, plant population structure, and gene flow. In: Real, L. (ed) Pollination Biology. Academic Press, New York, pp. 163–211.
Kazmer, D J. 1991. Isoelectric focusing procedures for the analysis of allozymic variation in minute arthropods. Ann Entomol Soc Am, 84, 332–339.
Kephart, S R. 1981. Breeding systems in Asclepias incarnata L., A. syriaca L, and A. verticillata L. Am J Bot, 68, 226–232.
Kephart, S R, and Heiser, C B. Jr. 1980. Reproductive isolation in Asclepias: lock and key hypothesis reconsidered. Evolution, 34, 738–746.
Kephart, S R, Wyatt, R, and Parrella, D. 1988. Hybridization in North American Asclepias. I. Morphological evidence. Syst Bot, 13, 456–473.
Kress, W J. 1981. Sibling competition and evolution of pollen unit, ovule number, and pollen vector in angiosperms. Syst Bot, 6, 101–112.
Levin, D A. 1981. Dispersal versus gene flow in plants. Ann Miss Bot Garden, 68, 233–253.
Macior, L W. 1965. Insect adaptation and behavior in Asclepias pollination. Bull Torrey Bot Club, 92, 114–126.
Marshall, D L, and Ellstrand, N C. 1985. Proximal causes of multiple paternity in wild radish, Raphanus sativus. Am Nat, 126, 596–605.
Manly, B F J. 1985. The Statistics of Natural Selection. Chapman and Hall, New York.
Morse, D H. 1982. The turnover of milkweed pollinia on bumble bees, and implications for outcrossing. Oecologia, 53, 187–196.
Morse, D H, and Fritz, R S. 1983. Contributions of diurnal and nocturnal insects to the pollination of common milkweed (Asclepias syriaca L.) in a pollen-limited system. Oecologia, 60, 190–197.
Mulcahy, D L, Robinson, R W, Ihara, M, and Kesseli, R. 1981. Gametophytic transcription for acid phosphatases in pollen of Cucurbita species hybrids. J Hered, 72, 353–354.
Pleasants, J M. 1991. Evidence for short-distance dispersal of pollinia in Asclepias syriaca L. Funct Ecol, 5, 75–82.
Peakall, R. 1989. A new technique for monitoring pollen flow in orchids. Oecologia, 79, 361–365.
Pleasants, J M, Horner, H T, and Ng, G. 1990. A labelling technique to track dispersal of milkweed pollinia. Funct Ecol, 4, 823–827.
Reed, T E, and Schull, W J. 1968. A general maximum likelihood estimation program. Am J Hum Genet, 20, 579–580.
Ritland, K. 1989. Correlated matings in the partial selfer Mimulusguttatus. Evolution, 43, 848–859.
Schall, B A. 1980. Measurement of gene flow in Lupinus texensis. Nature, 284, 450–451.
Schoen, D J, and Brown, A H D. 1991. Whole-and part-flower self-pollination in Glycine clandestina and G. argyrea and the evolution of autogamy. Evolution, 45, 1651–1664.
Schoen, D J, and Clegg, M T. 1984. Estimation of mating system parameters when outcrossing events are correlated. Proc Natl Acad Sci USA, 81, 5258–5262.
Shaw, D V, Kahler, A L, and Allard, R W. 1981. A multilocus estimator of mating system parameters in plant populations. Proc Natl Acad Sci USA, 78, 1298–1302.
Shore, J S. 1991. Tetrasomic inheritance and isozyme variation in Turnera ulmifolia vars. elegans Urb, and intermedia Urb. (Turneraceae). Heredity, 66, 305–312.
Shore, J S, and Barrett, S C H. 1987. Inheritance of floral and isozyme polymorphisms in Turnera ulmifolia L. J Hered, 78, 44–48.
Smyth, C A, and Hamrick, J L. 1987. Realized gene flow via pollen in artificial populations of musk thistle, Carduus nutans L. Evolution, 41, 613–619.
Thomson, J D, and Plowright, R C. 1980. Pollen carryover, nectar rewards, and pollinator behavior with special reference to Diervilla lonicera. Oecologia, 46, 68–74.
Thomson, J D, Price, M V, Waser, N M, and Stratton, D A. 1986. Comparative studies of pollen and fluorescent dye transport of bumble bees visiting Erythronium grandiflorum. Oecologia, 69, 561–566.
Weeden, N F, and Gottlieb, L D. 1979. Distinguishing allozymes and isozymes of phosphoglucoseisomerases by electrophoretic comparisons of pollen and somatic tissues. Biochem Genet, 17, 287–296.
Wendel, J F, and Weeden, N F. 1989. Visualization and interpretation of plant isozymes. In: Soltis, D. E, and Soltis, P. S. (eds) Isozymes in Plant Biology. Dioscorides Press, Portland Oregon, pp. 5–45.
Williams, J G K, Kubelik, A R, Livak, K J, Rafalski, J A, and Tingey, S V. 1990. DNA polymorphisms amplified by arbitrary primers are useful as genetic markers. Nucl Acids Res, 18, 6531–6535.
Willson, M F, and Rathcke, B J. 1974. Adaptive design of the floral display in Asclepias syriaca L. Am Midland Natural, 92, 47–57.
Willson, M F, and Price, P W. 1977. The evolution of inflorescence size in Asclepias (Asclepiadaceae). Evolution, 31, 495–511.
Wolfe, L M. 1987. Inflorescence size and pollinaria removal in Asclepias curassavica and Epidendrum radicans. Biotropica, 19, 86–89.
Wyatt, R. 1976. Pollination and fruit-set in Asclepias: a reappraisal. Am J Bot, 63, 845–851.
Wyatt, R. 1980. The reproductive biology of Asclepias tuberosa: I. Flower number, arrangement, and fruit-set. New Phytol, 85, 119–131.
Wyatt, R, and Broyles, S B. 1990. Reproductive biology of milkweeds. (Asclepias): recent advances. In: Kawano, S. (ed) Biological Approaches and Evolutionary Trends in Plants. Academic Press, Toronto, pp. 255–272.
Acknowledgements
I would like to thank Angela Baker, Mark DeBoer, Erika Hansell and especially Gus Lagos for technical assistance, and Laurence Packer and Helen Rodd for comments on the manuscript. The study was funded by a Natural Sciences and Engineering Research Council operating grant to J. S. Shore.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Shore, J. Pollination genetics of the common milkweed, Asclepias syriaca L.. Heredity 70, 101–108 (1993). https://doi.org/10.1038/hdy.1993.15
Received:
Issue Date:
DOI: https://doi.org/10.1038/hdy.1993.15
Keywords
This article is cited by
-
Genetic diversity assessment of Gymnema sylvestre (Retz.) R. Br. ex Sm. populations from Western Ghats of Maharashtra, India
Genetic Resources and Crop Evolution (2012)
-
Mating systems and interfertility of swamp milkweed (Asclepias incarnata ssp. incarnata and ssp. pulchra)
Heredity (1999)
-
Selection on reproductive characters: floral morphology in Asclepias syriaca
Heredity (1997)
-
Comparison of pollinator flight movements and gene dispersal patterns in Mimulus ringens
Heredity (1995)
-
The genetics and ecology of seed size variation in a biennial plant, Hydrophyllum appendiculatum (Hydrophyllaceae)
Oecologia (1995)