Rhododendron 'Ignacea', which is a prior to 1876 Ghent hybrid, has been determined to be a tetraploid using flow cytometry by
Dr. João Loureiro, Dr. Silvia Castro, José Cerca, 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.
Rhododendron 'Ignacea' tested at the high end of the range for tetraploid deciduous azaleas.
To date, all Ghent deciduous azaleas have tested as triploid or tetraploid.
Summary of Ploidy Levels
Triploid 'Bronze Unique',
Triploid 'Daviesii',
Triploid 'Deep Rose',
Triploid 'Gloria Mundi',
Triploid 'Josephine Klinger',
Tetraploid 'Bijou des Amateurs',
Tetraploid 'Comte de Flandre',
Tetraploid 'Heureuse Surprise',
Tetraploid 'Ignacea',
Tetraploid 'Julius Caesar',
Tetraploid 'Lelia',
Tetraploid 'Madame Gustave Guillemot',
Tetraploid 'Nancy Waterer',
Tetraploid 'Raphael de Smet'
Source: Arnold Arboretum Accession Number: 20419
John and Sally Perkins
