Rhododendron 'Isola Bella', which is a Brueckner hybrid documented as (Rhododendron dauricum 'Arctic Pearl' selfed) X Rhododendron fletcherianum 'Yellow Bunting', has been determined to be a diploid using flow cytometry by
Dr. João Loureiro, Dr. Silvia Castro, José Cerca Oliveira, and Mariana Castro
Plant Ecology and Evolution Group,
Centre for Functional Ecology,
Department of Life Sciences,
Faculty of Science and Technology,
University of Coimbra, Portugal.
Summary of Ploidy Levels
Diploid Rhododendron dauricum,
Diploid 'Isola Bella'
Source: RareFind Nursery
John and Sally Perkins
