Population differentiation and genetic variation inform translocation decisions for Liatris scariosa var. novae-angliae, a rare New England grassland perennial

Augmentation of small rare species populations is sometimes suggested on genetic grounds. However, outbreeding depression via dilution of local adaptation or break-up of genomic coadaptation may occur. These effects depend on the causes of population divergence. Here, we compare genetic measures of population divergence in Liatris scariosa var. novae-angliae, a rare New England perennial. We measured G(ST), neutral marker subdivision, and Q(ST), quantitative subdivision of propagule and juvenile plant traits. G(ST) was relatively high. Q(ST) for leaf shape exceeded G(ST), indicating local adaptation, while Q(ST) for other traits fell within or below the G(ST) range. Local adaptation appears low for juvenile traits, although the high G(ST) cautions against translocation because of potential coadaptation. If translocation is still required, however, donor populations should contain high quantitative genetic diversity. We assess population size and allozyme diversity as predictors of quantitative genetic variation, but find these poor proxies for direct measurement. (c) 2005 Elsevier Ltd. All rights reserved.