Estimation of the hybridization range between cv. somei-yoshino and wild flowering cherries, and the factors influencing inter-specific gene flow

Abstract

Somei-yoshino, one of the most famous flowering cherry cultivars, has been planted widely in Japan. To allow for appropriate planting that considers the genetic diversity of neighboring wild flowering cherry populations, the range of pollen-mediated gene flow between Somei-yoshino and related wild species was investigated. We also considered the factors that affect inter-specific gene flow. In a paternity analysis using six nuclear simple sequence repeat (SSR) markers, 95% of the pollen donors crossing with Somei-yoshino were identified as trees within 300 m of the maternal tree. Conversely, the farthest pollen flow from Somei-yoshino detected in seeds sampled from wild flowering cherries was approximately 190 m. In the bidirectional pollen-mediated gene flow, flowering phenology was an important factor in the gene flow pattern based on generalized linear models. Note, however, that flowering phenology differs among years and species, which may affect the range of hybridization between Somei-yoshino and wild flowering cherries.