Differences in the apportionment of molecular and morphological variation in North American strawberry and the consequences for genetic resource management

Variation for 24 morphological traits measured in a greenhouse environment and 36 randomly amplified polymorphic DNA (RAPD) markers was assessed among 318 wild octoploid strawberry (Fragaria spp.) genotypes from diverse habit ats across the northern USA. RAPD marker frequencies and certain leaf and f lower morphology traits (petiole color, leaf mass/area ratio, leaflet lengt h and width, flower and receptacle diameter, petal width, flowers/infloresc ence) were significantly different between the F. chiloensis-platypetala an d F. virginiana-glauca species complexes. The proportion of variation accou nted for by provenance effects was lower for the RAPD markers than for most morphological traits, especially in the F. virginiana-glauca species compl ex. Morphological traits of potential adaptive importance group the collect ion into provenances within each species-complex, and reflect the significa nt habitat and geographic differences across the region from which the germ plasm was collected. Variation among populations within provenances was low for the molecular and most morphological traits, with a much larger amount of variability among plants within populations. Most of the variation for the presumably more selectively-neutral RAPD data was among plants within p opulations and populations within provenances rather than among the provena nces that were recognized based on morphological traits, especially in the F. virginiana-glauca complex. Patterns of diversity for morphological trait s must be considered, along with more selectively-neutral molecular charact ers such as RAPDs, to formulate effective sampling strategies and to proper ly estimate the quantity and apportionment of diversity within this germpla sm.