The Ecological and Evolutionary Consequences of Clonality for Plant Mating Mario Vallejo-Mar´ ın, 1 Marcel E. Dorken, 2 and Spencer C.H. Barrett 3 1 School of Biological and Environmental Sciences, University of Stirling, Scotland, FK9 4LA, United Kingdom; email: mario.vallejo@stir.ac.uk 2 Department of Biology, Trent University, Petersborough, Ontario, K9J 7B8, Canada; email: marceldorken@trentu.ca 3 Department of Ecology and Evolutionary Biology, University of Toronto, Ontario, M5S 3B2; Canada; email: spencer.barrett@utoronto.ca Annu. Rev. Ecol. Evol. Syst. 2010. 41:193–213 First published online as a Review in Advance on August 10, 2010 The Annual Review of Ecology, Evolution, and Systematics is online at ecolsys.annualreviews.org This article’s doi: 10.1146/annurev.ecolsys.110308.120258 Copyright c  2010 by Annual Reviews. All rights reserved 1543-592X/10/1201-0193$20.00 Key Words clonal propagation, geitonogamy, inbreeding depression, pollination and mating, sexual systems, somatic mutations. Abstract Many flowering plants exhibit dual reproductive modes, producing both sex- ual and asexual offspring. The commonest form of asexual reproduction is clonal growth, in which vegetative modules (ramets) are produced by the parental genotype (genet). In plants, sexual and asexual reproduction usually occur simultaneously, and this can lead to allocation trade-offs and antag- onism between reproductive modes. Our review considers the ecological and evolutionary consequences of functional interactions between clonal re- production and pollination and mating. Clonal reproduction is commonly associated with mass flowering, restricted pollen dispersal, and geitonog- amous self-pollination, processes that can result in inbreeding depression and pollen discounting. We review evidence for the correlated evolution of clonality and sexual systems, particularly self-incompatibility, and identify several floral mechanisms that function to reduce mating costs by limiting selfing and pollen discounting. We conclude by discussing the loss of sex- uality in clonal plants and consider the genetic and environmental basis of sexual dysfunction. 193 Annu. Rev. Ecol. Evol. Syst. 2010.41:193-213. Downloaded from www.annualreviews.org by Universidad Nacional Autonoma de Mexico on 02/01/11. For personal use only.