Microsatellite analysis of pollen flow in Rhododendron metternichii var. hondoense

Microsatellite analysis was used to characterize the patterns of pollen flo w in a 150 m x 70 m quadrat containing 18 flowering trees of Rhododendron m etternichii Sieb. et Zucc. var. hondoense Nakai. Using six microsatellite g enetic markers and exclusion analysis, we determined the paternal trees of 216 seedlings germinated from five fruits produced by four adults. Each fru it was pollinated by a small number of largely adjacent trees, but 20-30% o f pollen came from outside the quadrat. Adult trees that produced many flow ers had a high self-pollination rate. A directional flow of pollen from lat e-blooming trees to early ones was observed.