http://rosebayblog.blogspot.com/2011/11/prinophyllum-x-calendulaceum-engine-gap.html

H: Monday, November 28, 2011

prinophyllum X calendulaceum Engine Gap is a Triploid

Rhododendron prinophyllum X Rhododendron calendulaceum "Engine Gap", which is a John and Sally Perkins hybrid, 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 prinophyllum is diploid. Rhododendron calendulaceum is a tetraploid species.

In this case of this triploid (39 chromosomes), a diploid crossed with a tetraploid produced a triploid indicating normal meiosis occurred where the diploid contributed a 1x gamete (13 chromosomes) and the tetraploid contributed a 2x gamete (26 chromosomes).

Summary of Ploidy Levels

Diploid Rhododendron prinophyllum,
Triploid Rhododendron prinophyllum X Rhododendron calendulaceum "Engine Gap",
Tetraploid Rhododendron calendulaceum

This seedling was grown on by

Lindy Johnson
Appalachian Native Plants
676 Waddell Road
PO Box 736
Mountain City, TN 37683

Source: John and Sally Perkins
Source: Appalachian Native Plants

John and Sally Perkins
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