Highly polymorphic nuclear microsatellite markers reveal detailed patterns of genetic variation in natural populations of Yezo spruce in Hokkaido

The Yezo spruce (Picea jezoensis) has attracted attention as a species commonly used for afforestation in Hokkaido. However, there is no information available for assessing appropriate seed and planting zones for this species. We developed 21 nuclear microsatellite markers for P. jezoensis and used them to examine the genetic structure of nine natural populations (288 trees). Based on the 31 samples, the 21 markers were highly polymorphic, with an average expected heterozygosity greater than 0.84. When we applied ten effective markers to nine populations in Hokkaido, no clear regional differences in genetic diversity were detected. STRUCTURE analysis revealed that, aside from certain geographically isolated or peripheral populations, the populations within planting zones belonged to a single cluster. Thus, based on our marker data, with a few exceptions, there appears to be a single seed zone within the planting zones in Hokkaido.