Identifying new sources of genes that determine cyclic flowering in rocky mountain populations of Fragaria virginiana ssp. glauca Staudt

Abstract

The genes that determine cyclic flowering in all commercially grown cultivars of strawberry (Fragaria Xananassa Duch.) were derived from a single source of F. virginians esp. glauca from the Wasatch Mountains in Utah. To broaden the germplasm base of cyclic flowering cultivars, we evaluated the reproductive characteristics 5 to 10 colonies of F. virginiana ssp. glauca from each of 32 Rocky Mountain sites ranging in elevation from 700 to 2900 m. Populations at high and low elevations had high percentages of putative day neutrals with cyclic flowering (43% to 100%) and hermaphrodites (20% to 80%), although most hermaphrodites were only partially fertile. There was also little association between elevation and crown numbers or flower number per cycle, but the total number of flowers per plant was negatively correlated with elevation. Fruit size was not significantly correlated with fruit number. When the data were subjected to a principal component analysis, two distinct groups were identified: one from the Black Hills of South Dakota and the other from low-elevation sites in Idaho and northwestern Montana. These patterns mirrored previously described patterns based on leaf traits.