Genetic variation and differentiation of floral morphology in wild Primula sieboldii evaluated by image analysis data and SSR markers

Abstract

Primula sieboldii (E. Morren), the ancestor of the Japanese garden Primula, is in danger of extinction in the wild. Genetic diversity is a key component for conservation efforts associated with population management. Genetic diversity in visible traits and several molecular makers were evaluated, respectively. Since it is difficult to determine the degree to which genetic and environmental differences contribute to observed phenotypic variation in natural habitats. A common-garden approach is used. The contribution of genetic and environmental differences to variation in petal shape and area of Primula sieboldii were evaluated. Samples from 108 genets gathered from five natural populations in three regions of Japan were analyzed in a commongarden experiment and also analyzed using eight microsatellite markers. From the results of quantitative evaluation based on image analysis, broad genetic variation in petal traits within populations and low level of population differentiation was found. For all petal shapes, Qst was smaller than Fst, suggesting that wild populations might be under moderate selective pressure for a specific phenotype. For petal area, Qst was nearly equal to F st, suggesting that population differentiation has been caused mainly by genetic drift.