'Siskin' is a Tetraploid

Rhododendron 'Siskin', which is a Waterer Knaphill documented as a crossed between Rhododendron luteum and Rhododendron molle, has been determined to be a tetraploid 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 molle,
Tetraploid Rhododendron luteum,
Tetraploid 'Siskin'

Source: Planeview Nursery

John and Sally Perkins

'Embley Crimson' is a Tetraploid

Rhododendron 'Embley Crimson', which is a 1965 Knaphill, 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.

Summary of Ploidy Levels

Tetraplid 'Brazil',
Tetraploid 'Embley Crimson'

Source: Arnold Arboretum Accession Number: 1230-65-C

John and Sally Perkins

'Lady Roseberry' is a Tetraploid

Rhododendron 'Lady Roseberry', which is a Knaphill 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.

Summary of Ploidy Levels

Tetraploid 'Lady Roseberry'

Source: Arnold Arboretum Accession Number: 632-61

John and Sally Perkins