Summary: High variation in clonal vs. sexual reproduction in populations of the wild
strawberry, Fragaria virginiana (Rosaceae)
John A. Wilk1, Andrea T. Kramer1,2 and Mary V. Ashley1,*
Department of Biological Sciences, University of Illinois Chicago, M/C 066, 845 W. Taylor St, Chicago IL 60607, USA and
Botanic Gardens Conservation International and Chicago Botanic Garden, 1000 Lake Cook Road, Glencoe, IL 60022, USA
Received: 29 April 2009 Returned for revision: 12 June 2009 Accepted: 11 August 2009 Published electronically: 1 October 2009
Background and Aims Many plants reproduce both clonally and sexually, and the balance between the two
modes of reproduction will vary among populations. Clonal reproduction was characterized in three populations
of the wild strawberry, Fragaria virginiana, to determine the extent that reproductive mode varied locally
between sites. The study sites were fragmented woodlands in Cook County, Illinois, USA.
Methods A total of 95 strawberry ramets were sampled from the three sites via transects. Ramets were mapped
and genotyped at five variable microsatellite loci. The variability at these five loci was sufficient to assign plants
to clones with high confidence, and the spatial pattern of genets was mapped at each site.
Key Results A total of 27 distinct multilocus genotypes were identified. Of these, 18 genotypes were detected
only once, with the remaining nine detected in multiple ramets. The largest clone was identified in 16 ramets. No
genets were shared between sites, and each site exhibited markedly different clonal and sexual recruitment pat-
terns, ranging from two non-overlapping and widespread genets to 19 distinct genets. Only one flowering genet
was female; the remainder were hermaphrodites.