An open pollinated seedling of Rhododendron 'Solidarity' has been determined to be a triploid using flow cytometry by
Dr. João Loureiro, Dr. Silvia Castro, 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 'Solidarity' is known to produce open pollinated seedpods and this seed will sometimes germinate. The plant tested is a seedling from such a seedpod.
Summary of Ploidy Levels
Triploid 'Solidarity' OP
Source: John and Sally Perkins
John and Sally Perkins