Rhododendron 'Doreen Gale', which is a Sanders hybrid documented as 'Point Defiance' x 'Trude Webster', 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 'Doreen Gale' has as ancestors 'Anna', 'Norman Gill', 'The Honourable Jean Marie de Montague', 'Broughtonii', 'Cynthia', 'Pink Pearl', 'Marinus Koster', 'Point Defiance', 'Countess of Derby', and 'Trude Webster'.
In the case of the tetraploid 'Doreen Gale', a tetraploid crossed with a tetraploid produced a tetraploid indicating that normal reduced meiosis most likely occurred for both parents. In other words, 'Doreen Gale' having 52 chromosomes received 26 chromosomes from the tetraploid 'Point Defiance' and 26 chromosomes from the tetraploid 'Trude Webster'.
Summary of Ploidy Levels
Diploid 'Anna',
Diploid 'Norman Gill',
Diploid 'The Honourable Jean Marie de Montague',
Triploid 'Broughtonii',
Triploid 'Cynthia',
Triploid 'Pink Pearl',
Tetraploid 'Countess of Derby',
Tetraploid 'Doreen Gale',
Tetraploid 'Gorgeous George',
Tetraploid 'Marinus Koster',
Tetraploid 'Point Defiance',
Tetraploid 'Trude Webster'
Source Marc Colombel
John and Sally Perkins
