The Spatial Structure of Sexual and Cytonuclear Polymorphism in the Gynodioecious Beta vulgaris ssp. maritima: I/ at a Local Scale

Corresponding author: Joël Cuguen, Laboratoire de Génétique et Evolution des Populations Végétales, UPRESA CNRS 8016, FR CNRS 1818, Bâtiment SN2, Université de Lille I, 59655 Villeneuve d'Ascq Cedex, France., joel.cuguen{at}univ-lille1.fr (E-mail)

Communicating editor: O. SAVOLAINEN

We have analyzed the spatial distribution of the sex phenotypes and of mitochondrial, chloroplast, and nuclear markers within two gynodioecious populations of Beta vulgaris ssp. maritima. Within both populations, sexual phenotype variation is controlled mainly by the cytoplasmic genotype, although in one study population a joint polymorphism of cytonuclear factors is clearly involved. In spite of contrasts in the ecology (mainly due to different habitats), a clear common feature in both populations is the highly patchy distribution of cytoplasmic haplotypes, contrasting with the wide distribution of nuclear diversity. This high contrast between cytoplasmic vs. nuclear spatial structure may have important consequences for the maintenance of gynodioecy. It provides opportunities for differential selection since nuclear restorer alleles are expected to be selected for in the presence of their specific cytoplasmic male sterile (CMS) type, but to be neutral (or selected against if there is a cost of restoration) in the absence of their CMS type. Selective processes in such a cytonuclear landscape may explain the polymorphism we observed at restorer loci for two CMS types.

This article has been cited by other articles:

				D. E. McCauley and M. F. Bailey Recent advances in the study of gynodioecy: the interface of theory and empiricism Ann. Bot., June 10, 2009; (2009) mcp141v1. [Abstract] [Full Text] [PDF]

				T. R. Meagher Linking the Evolution of Gender Variation to Floral Development Ann. Bot., August 1, 2007; 100(2): 165 - 176. [Abstract] [Full Text] [PDF]

				M. E. Welch, M. Z. Darnell, and D. E. McCauley Variable Populations Within Variable Populations: Quantifying Mitochondrial Heteroplasmy in Natural Populations of the Gynodioecious Plant Silene vulgaris Genetics, October 1, 2006; 174(2): 829 - 837. [Abstract] [Full Text] [PDF]

				M. GLAETTLI, L. PESCATORE, and J. GOUDET Proximity-dependent Pollen Performance in Silene vulgaris Ann. Bot., August 1, 2006; 98(2): 431 - 437. [Abstract] [Full Text] [PDF]

				S. Fenart, P. Touzet, J.-F. Arnaud, and J. Cuguen Emergence of gynodioecy in wild beet (Beta vulgaris ssp. maritima L.): a genealogical approach using chloroplastic nucleotide sequences Proc R Soc B, June 7, 2006; 273(1592): 1391 - 1398. [Abstract] [Full Text] [PDF]

				T. Stadler and L. F. Delph Ancient mitochondrial haplotypes and evidence for intragenic recombination in a gynodioecious plant PNAS, September 3, 2002; 99(18): 11730 - 11735. [Abstract] [Full Text] [PDF]