John and Sally Perkins
Figure 1: Triploids can be Fertile and can create a Bidirectional Pathway Between Ploidy Levels
In spring 1913, George V is the first Windsor King of England, Woodrow Wilson is serving his first term as President of the United States, and World War I is a future event. The 2 most popular Rhododendrons in the world are 'Pink Pearl', a 1890's Waterer hybrid, and 'Cynthia', a 1850's Noble and Standish hybrid. On a beautiful spring day in 1913 if you are Henry 'Harry' White, a nursery manager in Sunningdale, England you cross 'Pink Pearl' by 'Cynthia'. You later name a seedling from this cross 'Countess of Derby'.
In spring 1961, John Kennedy is the young handsome President of the United States and Vietnam is a country unknown to most Americans. On a beautiful spring day in 1961 if you are Harold Greer, living in Eugene, Oregon, you self 'Countess of Derby'. You later name a seedling from this cross 'Trude Webster'.
In spring 1969, Richard Nixon is the President of the United States and Watergate is simply an office building in the DC area. On a beautiful spring day in 1969 if you are Robert Korn in Renton, Washington, you place the pollen from 'Gomer Waterer', a 1900 Waterer 'Pink Pearl' hybrid, onto 'Diane'. You later name a seedling from this cross 'Phyllis Korn'.
In spring 1988, George H. Bush is the Vice President of the United States and Iraq is simply a country somewhere in the Middle East. On a beautiful spring day in 1988 if you are Jim Barlup, living in Bellevue, Washington, you cross 'Whitney's Late Peach' by 'Phyllis Korn'. You later name a seedling from this cross 'Summer Peach'.
In spring 2001, George W. Bush is the President of the United States and the Twin Towers in New York City are still standing. On a beautiful spring day in 2001 if you are Jim Barlup, living in Bellevue, Washington, you cross 'Phyllis Korn' by 'Trude Webster' to create several viable offspring.
So what have you done starting in 1913?
Well you took 2 fertile triploids from the 19th century, namely 'Pink Pearl' and 'Cynthia' and created a tetraploid, namely 'Countess of Derby'. You then selfed the tetraploid 'Countess of Derby' creating a tetraploid, namely 'Truder Webster'. You then placed pollen from the triploid 'Gomer Waterer' onto a diploid seed parent, namely 'Diane' creating a triploid, namely 'Phyllis Korn'. You then used the pollen of a triploid, namely Phyllis Korn' to create a diploid, namely 'Summer Peach'. You then placed the pollen of the tetraploid 'Trude Webster' onto the triploid seed parent 'Phyllis Korn' and produced a series of pentaploid seedlings. See figure 1.
By doing so you ended the myth that triploids are always sterile showing that triploids can be both seed and pollen parents. Moreover, triploids, when used in hybridization, produce both reduced and unreduced gametes. You demonstrated that triploids provide a pathway for the bidirectional transfer of genes between diploids, triploids, tetraploids, and pentaploids.
It took you a few beautiful spring days doing crosses, a few changes of names and addresses, nearly 90 years, and a team of young researchers at the University of Coimbra in Portugal to confirm your results but all in all not a bad piece of work.
Summary of Ploidy Levels
Diploid 'Diane',
Diploid 'Madame Carvalho',
Diploid 'Summer Peach',
Triploid 'Broughtonii',
Triploid 'Cynthia',
Triploid 'Gomer Waterer',
Triploid 'Pink Pearl',
Triploid 'Phyllis Korn',
Tetraploid 'Countess of Derby',
Tetraploid 'Trude Webster', and
Pentaploid Seedlings of 'Phyllis Korn' X 'Trude Webster'
Flow cytometry to determine ploidy levels performed 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.
The following people and organizations donored samples for this reasearch:
John Abbott,
Vivian Abney of East Fork Nursery,
Arnold Arboretum,
Audra State Park, WV,
Jim Barlup,
Barlett Arboretum,
Jane Brooks,
Joe Bruso,
Canobie Lake, NH,
Dick Cavender,
Werner Brack,
Ned Brockenbrough,
Marc Colombel,
Bruce Clyburn,
Connecticut College Arboretum,
Mike Creel,
Al Fitzburg,
Robert Fox,
Harold Greer of Greer Gardens,
George Hibben,
Highstead Arboretum,
Don Hyatt,
Lindy Johnson of Appalachian Native Plants,
Richard Jaynes of Broken Arrow Nursery,
Doug Jolley,
Fred Knippel,
Longwood Gardens,
Ron Miller,
Dick Murcott,
John and Sally Perkins,
Planeview Nursery,
Ron Rabideau of RareFind Nursery,
Ellie Sather of Whitney Gardens,
Stoddard Blog, NH,
John Thornton,
Hendrik Van Oostand of Azaleatuin,
Kathy Van Veen of Van Veen Nursery
