INTER‐POPULATIONAL DIFFERENTIATION AND ADAPTATION IN THE PERENNIAL, DIPLOID SPECIES FRAGARIA VESCA L.

Abstract

Inter‐populational differentiation and adaptation in California Fragaria vesca L. were examined using plants collected from 13 natural sites, grown in a common greenhouse and analyzed for 25 quantitative traits and 2 enzyme systems. Inter‐populational variation was estimated by analysis of variance and genetic identity techniques, and micro‐ and macro‐environmental measurements were made at each site. Stepwise multiple regressions were completed on the morphological‐environmental variations and the allozyme frequency‐environmental variations. Clonal propagules were compared under three controlled environmental conditions. F. vesca likely has undergone considerable ecological differentiation since significant inter‐populational variation was observed in many polygenic and monogenic traits. Numerous significant correlations between environmental and character variations were found, and in many, only a few environmental variables “explained” much of that variation. Inter‐populational differences in the abilities of plants to accumulate biomass and survive under salt, nutrient and shade stresses were also found. Although many of the ecotypes of F. vesca showed some phenotypic plasticity, the species is a “specialist.” Variations in root/shoot ratios occurred in biotypes grown under different conditions. Plants generally allocated more energy to aboveground biomass under shade stress and to root biomass under nutrient stress.