Genetic diversity in natural populations of two geographic isolates of Korean black raspberry

摘要

A molecular genetic marker, inter-simple sequence repeats (I-SSR), was analyzed to monitor the level and distribution of genetic diversity in 16 populations of an endemic bramble in Korea, Rubus coreanus. A total of 60 I-SSR variants, amplified withsix I-SSR primers, were observed in 205 Korean black raspberry bushes, which revealed individual specific amplicon profiles. Relatively low level of genetic diversity within populations was observed (mean: 0.242). From the results of AMOVA, a moderatelyhigh degree of population differentiation (PHI_(ST) = 0.185) was estimated and a low level of genetic differentiation (PHI_(CT) = 0.056) was observed among four geographic groups. Excluding two Jeju island populations from the analysis resulted in a lowering of the degree of genetic differentiation among geographic groups (PHI_(CT) = 0,037), which suggested that two populations in the Jeju island group was genetically much differentiated from the 14 peninsular populations. Founder effects on Jeju island populations and isolation by the sea might be responsible for such differentiation. Genetic relationships among the populations revealed two distinct groups of Jeju island and Korea peninsular. Overall pattern of genetic relationships among populationsin Korea peninsular group was relatively well coincided with geographic affinity. Although Korean black raspberry has been known to reproduce both sexually and vegetatively, distribution by vegetative reproduction may be restricted within 30 m. Information on molecular genetic diversity based on I-SSR variants could provide molecular genetic informations for gene conservation and future breeding of new local cultivars having superior fruit characters.