Rosebay Blog

Reminder: P4M Workday: Planeview Nursery - Potting @ Sat Jan 28 10am - 12pm (ARS Massachusetts Chapter Calendar)

2012-01-26T07:00:00.001-08:00

P4M Workday: Planeview Nursery - Potting

Pot Rooted Cuttings

When

Sat Jan 28 10am – 12pm Eastern Time

Where

770 Wapping Road, Portsmouth, RI (map)

Calendar

ARS Massachusetts Chapter Calendar

Who

•	john.a.perkins@gmail.com - creator

Invitation from Google Calendar

You are receiving this email at the account john.a.perkins@gmail.com because you set a reminder for this event on the calendar ARS Massachusetts Chapter Calendar.

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Reminder: P4M Workday: Planeview Nursery - Potting @ Sat Jan 28 10am - 12pm (ARS Massachusetts Chapter Calendar)

2012-01-21T07:00:00.001-08:00

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P4M Workday: Planeview Nursery - Potting

Pot Rooted Cuttings

When

Sat Jan 28 10am – 12pm Eastern Time

Where

770 Wapping Road, Portsmouth, RI (map)

Calendar

ARS Massachusetts Chapter Calendar

Who

•	john.a.perkins@gmail.com - creator

Invitation from Google Calendar

You are receiving this email at the account john.a.perkins@gmail.com because you set a reminder for this event on the calendar ARS Massachusetts Chapter Calendar.

You can change your reminders for specific events in the event details page in https://www.google.com/calendar/.

Reminder: Massachusetts Chapter Meeting - Putnam Building @ Sun Jan 22 1:30pm - 4pm (ARS Massachusetts Chapter Calendar)

2012-01-20T10:30:00.001-08:00

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Massachusetts Chapter Meeting - Putnam Building

MeetingKarel Bernady will talk on "Celebrating 75 Years of the Deutsche Gesellschaft"

When

Sun Jan 22 1:30pm – 4pm Eastern Time

Where

Elm Bank Wellsley, MA (map)

Calendar

ARS Massachusetts Chapter Calendar

Who

•	john.a.perkins@gmail.com - creator

Invitation from Google Calendar

You are receiving this email at the account john.a.perkins@gmail.com because you set a reminder for this event on the calendar ARS Massachusetts Chapter Calendar.

You can change your reminders for specific events in the event details page in https://www.google.com/calendar/.

Reminder: Massachusetts Chapter Meeting - Putnam Building @ Sun Jan 22 1:30pm - 4pm (ARS Massachusetts Chapter Calendar)

2012-01-15T10:30:00.001-08:00

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Massachusetts Chapter Meeting - Putnam Building

MeetingKarel Bernady will talk on "Celebrating 75 Years of the Deutsche Gesellschaft"

When

Sun Jan 22 1:30pm – 4pm Eastern Time

Where

Elm Bank Wellsley, MA (map)

Calendar

ARS Massachusetts Chapter Calendar

Who

•	john.a.perkins@gmail.com - creator

Invitation from Google Calendar

You are receiving this email at the account john.a.perkins@gmail.com because you set a reminder for this event on the calendar ARS Massachusetts Chapter Calendar.

You can change your reminders for specific events in the event details page in https://www.google.com/calendar/.

Reminder: P4M Workday: Planeview Nursery - Potting @ Sat Jan 14 10am - 12pm (ARS Massachusetts Chapter Calendar)

2012-01-12T07:00:00.001-08:00

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P4M Workday: Planeview Nursery - Potting

Pot Rooted Cuttings

When

Sat Jan 14 10am – 12pm Eastern Time

Where

770 Wapping Road, Portsmouth, RI (map)

Calendar

ARS Massachusetts Chapter Calendar

Who

•	john.a.perkins@gmail.com - creator

Invitation from Google Calendar

You are receiving this email at the account john.a.perkins@gmail.com because you set a reminder for this event on the calendar ARS Massachusetts Chapter Calendar.

You can change your reminders for specific events in the event details page in https://www.google.com/calendar/.

Reminder: Board Meeting @ Wed Jan 11 7:30pm - 9pm (ARS Massachusetts Chapter Calendar)

2012-01-09T16:30:00.001-08:00

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Board Meeting

When

Wed Jan 11 7:30pm – 9pm Eastern Time

Where

Hardings (map)

Calendar

ARS Massachusetts Chapter Calendar

Who

•	John Perkins - creator

Invitation from Google Calendar

You are receiving this email at the account john.a.perkins@gmail.com because you set a reminder for this event on the calendar ARS Massachusetts Chapter Calendar.

You can change your reminders for specific events in the event details page in https://www.google.com/calendar/.

Reminder: P4M Workday: Planeview Nursery - Potting @ Sat Jan 14 10am - 12pm (ARS Massachusetts Chapter Calendar)

2012-01-07T07:00:00.001-08:00

more details »

P4M Workday: Planeview Nursery - Potting

Pot Rooted Cuttings

When

Sat Jan 14 10am – 12pm Eastern Time

Where

770 Wapping Road, Portsmouth, RI (map)

Calendar

ARS Massachusetts Chapter Calendar

Who

•	john.a.perkins@gmail.com - creator

Invitation from Google Calendar

You are receiving this email at the account john.a.perkins@gmail.com because you set a reminder for this event on the calendar ARS Massachusetts Chapter Calendar.

You can change your reminders for specific events in the event details page in https://www.google.com/calendar/.

January Newsletter

2012-01-04T20:44:00.000-08:00

Reminder: Board Meeting @ Wed Jan 11 7:30pm - 9pm (ARS Massachusetts Chapter Calendar)

2012-01-04T16:30:00.001-08:00

more details »

Board Meeting

When

Wed Jan 11 7:30pm – 9pm Eastern Time

Where

Hardings (map)

Calendar

ARS Massachusetts Chapter Calendar

Who

•	John Perkins - creator

Invitation from Google Calendar

You are receiving this email at the account john.a.perkins@gmail.com because you set a reminder for this event on the calendar ARS Massachusetts Chapter Calendar.

You can change your reminders for specific events in the event details page in https://www.google.com/calendar/.

Van Veen Order List

2011-12-27T09:36:00.001-08:00

Dear All,

Attached is the Van Veen list in an excel format. There are three sections as you go across the sheet – first the rhododendrons, then the species, and then the azaleas.

Please take the holiday season and look them over and decide which ones and related amounts you may want. You can return the sheet to me and highlight the ones and number you want, or you can send me an email with the name and amount. I will confirm anything you send me. If you could get orders back to me by the 8^th of January, I will collate and get the orders off to Kathy Van Veen immediately. Shortly after the order is sent out and the distribution/payment logistics are finalized, I will notify everyone so they may plan appropriately.

You should send/forward your replies to plympton@verizon.net That is my home email address. This email is being sent from a work email address and if you respond/reply to this email address, the spam filters may not let it through. I think I have sent this email appropriately so only your email address is showing, and to not violate your privacy.

We can always use the help if anyone is interested in shepherding the Van Veen ordering for next year. We would love to have you on board.

Thank you for your understanding and patience. I hope everyone has the best upcoming year imaginable, and has/is having a terrific holiday season.

Sincerely,

Don Brophy

Reminder: Board Meeting @ Wed Dec 14 7:30pm - 9pm (ARS Massachusetts Chapter Calendar)

2011-12-12T16:30:00.001-08:00

more details »

Board Meeting

When

Wed Dec 14 7:30pm – 9pm Eastern Time

Where

Hardings (map)

Calendar

ARS Massachusetts Chapter Calendar

Who

•	John Perkins - creator

Invitation from Google Calendar

You are receiving this email at the account john.a.perkins@gmail.com because you set a reminder for this event on the calendar ARS Massachusetts Chapter Calendar.

You can change your reminders for specific events in the event details page in https://www.google.com/calendar/.

Lake Keowee Population contains Triploids

2011-12-08T01:06:00.000-08:00

Deciduous azalea hybrids selected from a native population near Lake Keowee, South Carolina have been determined to be triploids using flow cytometry by a team lead by Dr. Ranney.

Summary of Ploidy Levels

Triploid Deciduous azalea hybrids from Lake Keowee population

Source: Lake Keowee population
Source: Clarence Towe

John and Sally Perkins

Reminder: Board Meeting @ Wed Dec 14 7:30pm - 9pm (ARS Massachusetts Chapter Calendar)

2011-12-07T16:30:00.001-08:00

more details »

Board Meeting

When

Wed Dec 14 7:30pm – 9pm Eastern Time

Where

Hardings (map)

Calendar

ARS Massachusetts Chapter Calendar

Who

•	john.a.perkins@gmail.com - creator

Invitation from Google Calendar

You are receiving this email at the account john.a.perkins@gmail.com because you set a reminder for this event on the calendar ARS Massachusetts Chapter Calendar.

You can change your reminders for specific events in the event details page in https://www.google.com/calendar/.

Wine Spring Bald contains Triploids

2011-12-07T01:57:00.000-08:00

Two deciduous azalea hybrids selected from a native population on Wine Spring Bald, North Carolina have been determined to be triploids using flow cytometry by a team lead by Dr. Ranney.

Summary of Ploidy Levels

Triploid 2 deciduous azalea hybrids from Wine Spring Bald population

Source: Wine Spring Bald population
Source: Clarence Towe and Ron Miller

John and Sally Perkins

Cherokee County Population contains Triploids

2011-12-06T03:26:00.000-08:00

Four deciduous azalea hybrids selected from a native population in Cherokee County, Georgia have been determined to be triploids 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

Triploid 4 deciduous azalea hybrids from Cherokee County population

Source: Cherokee County population
Source: Charles Andrews

John and Sally Perkins

Dawsonville Population contains Triploids

2011-12-05T05:33:00.000-08:00

A deciduous azalea hybrid in a native population in Dawsonville, Georgia has been determined to be a triploid 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.

This Dawsonville population contains Rhododendron arborescens, Rhododendron canescens, Rhododendron periclymenoides, and Rhododendron calendulaceum.

Summary of Ploidy Levels

Diploid Rhododendron arborescens
Diploid Rhododendron canescens
Diploid Rhododendron periclymenoides
Triploid 1 deciduous azalea hybrid in Dawsonville population
Tetraploid Rhododendron calendulaceum

Source: Dawsonville population
Source: Charles Andrews

John and Sally Perkins

'July Jester' X 'My Mary' is a Triploid

2011-12-03T05:00:00.000-08:00

'July Jester' X 'My Mary', 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.

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 cumberlandense
Diploid Rhododendron prunifolium
Triploid 'July Jester' X 'My Mary'
Tetraploid Rhododendron austrinum
Tetraploid 'My Mary'

Source: John and Sally Perkins

John and Sally Perkins

"viscosum glaucum not" X 'Smoky Mountaineer' is a Triploid

2011-12-01T17:04:00.000-08:00

"viscosum glaucum not" X Rhododendron calendulaceum 'Smoky Mountaineer', 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.

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

Triploid "viscosum glaucum not" X Rhododendron calendulaceum 'Smoky Mountaineer'
Tetraploid Rhododendron calendulaceum
Tetraploid Rhododendron calendulaceum 'Smoky Mountaineer'

This seedling was grown on by

Lindy Jackson
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

(pruniflorum X arborescens) X 'Smoky Mountaineer' is a Triploid

2011-11-30T03:26:00.000-08:00

(Rhododendron pruniflorum X Rhododendron arborescens) X Rhododendron calendulaceum 'Smoky Mountaineer', 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 pruniflorum and Rhododendron arborescens are diploid species. 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 pruniflorum,
Diploid Rhododendron arborescens,
Triploid (Rhododendron pruniflorum X Rhododendron arborescens) X Rhododendron calendulaceum 'Smoky Mountaineer',
Tetraploid Rhododendron calendulaceum,
Tetraploid Rhododendron calendulaceum 'Smoky Mountaineer'

This seedling was grown on by

Lindy Jackson
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

Diploid Tsutsusi Rhododendron Species

2011-11-29T04:58:00.000-08:00

In the paper "Flow Cytometric Analysis of Ploidy in Rhododendron (subgenus Tsutsusi)", S. De Schepper1, L. Leus, M. Mertens, E. Van Bockstaele, and M. De Loose found 6 Rhododendron species of section Tsutsusi to be diploid.

In the paper "Ploidy Levels and Relative Genome Sizes of Diverse Species, Hybrids, and Cultivars of Rhododendron", Jeff R. Jones, Thomas G. Ranney, Nathan P. Lynch, and Stephen L. Krebs found 1 Rhododendron species of section Tsutsusi to be diploid. Results from this paper are denoted by ^j.

Triploids hybrid evergreen azaleas from these 2 papers are also listed here.

Diploid

Rhododendron indicum
Rhododendron kiusianum
Rhododendron mucronatum
Rhododendron noriakianum
Rhododendron scabrum
Rhododendron simsii
Rhododendron stenopetalum ‘Linearifolium’ ^j

Triploid

'Crimson Majesty' ^j
'Euratom'
'Euratom Orange'
'Red Wing'

Mixaploid

'Casablanca Tetra'

prinophyllum X calendulaceum Engine Gap is a Triploid

2011-11-28T04:46:00.000-08:00

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 Jackson
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

'Canobie Candy' X calendulaceum Engine Gap is a Triploid

2011-11-27T08:20:00.000-08:00

'Canobie Candy' 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.

'Canobie Candy' 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 'Canobie Candy',
Triploid 'Canobie Candy' X Rhododendron calendulaceum "Engine Gap",
Tetraploid Rhododendron calendulaceum

This seedling was grown on by

Lindy Jackson
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

molle x luteum is a Triploid

2011-11-26T16:49:00.000-08:00

Rhododendron molle X Rhododendron luteum, 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 molle is diploid species. Rhododendron luteum 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 molle,
Triploid Rhododendron molle X Rhododendron luteum,
Tetraploid Rhododendron luteum

This seedling was grown on by

Lindy Jackson
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

'Aamurusko' is a Triploid

2011-11-25T11:09:00.000-08:00

Rhododendron 'Aamurusko', which is a Finnish Ghent 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.

Summary of Ploidy Levels

Diploid 'Miniatum Floribundum',
Triploid 'Aida',
Triploid 'Aamurusko',
Triploid 'Bronze Unique',
Triploid 'Croceum Tricolor',
Triploid 'Daviesii',
Triploid 'Deep Rose',
Triploid 'Freya',
Triploid 'Gloria Mundi',
Triploid 'Il Tasso',
Triploid 'Josephine Klinger',
Triploid 'Phebe',
Triploid 'Phidias',
Triploid 'Pontica Album',
Triploid 'Van Houttei Flore Pleno',
Triploid 'Velasquez',
Triploid/Tetraploid 'Praxitèle',
Tetraploid 'Admiraal De Ruyter',
Tetraploid 'Altaclerensis',
Tetraploid 'Ariel',
Tetraploid 'Beaté Céleste',
Tetraploid 'Bijou des Amateurs',
Tetraploid 'Bouquet de Flore',
Tetraploid 'Cardinal,
Tetraploid 'Comte de Flandre',
Tetraploid 'Corneille',
Tetraploid 'Directeur Charles Baumann',
Tetraploid 'Durante Alle',
Tetraploid 'Electum',
Tetraploid 'Eugénie',
Tetraploid 'Fénelon',
Tetraploid 'Flameola Incarnata',
Tetraploid 'Héroine Plena,
Tetraploid 'Heureuse Surprise',
Tetraploid 'Hollandia',
Tetraploid 'Hora',
Tetraploid 'Ignacea',
Tetraploid 'Igneum Novum',
Tetraploid 'Il Tasso',
Tetraploid 'Jenny Lind',
Tetraploid 'Juliana Nova',
Tetraploid 'Julius Caesar',
Tetraploid 'Leibuir',
Tetraploid 'Lelia',
Tetraploid 'Madame Gustave Guillemot',
Tetraploid 'Marie Verschaffelt',
Tetraploid 'Minerva',
Tetraploid 'Nancy Waterer',
Tetraploid 'Oscar I',
Tetraploid 'Perfecta',
Tetraploid 'Princesse d' Orange',
Tetraploid 'Raphael de Smet'

Source: Kristian Theqvist

John and Sally Perkins

'Frosthexe' is a Triploid

2011-11-24T06:24:00.000-08:00

Rhododendron 'Frosthexe', which is a Reich hybrid documented as Rhododendron anthopogon ssp. anthopogon X Rhododendron lapponicum, 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.

Summary of Ploidy Levels

Diploid Rhododendron dauricum,
Diploid Rhododendron hippophaeoides,
Diploid Rhododendron keiskei,
Diploid Rhododendron lapponicum,
Diploid Rhododendron micranthum,
Diploid Rhododendron minus,
Diploid Rhododendron mucronulatum,
Diploid Rhododendron racemosum,
Triploid 'Angel Powder',
Triploid 'April Rhapsody',
Triploid 'Bluenose',
Triploid 'Evening Sky',
Triploid 'Frosthexe',
Triploid 'Kehr's White Ruffles',
Triploid 'Purple Gem',
Triploid 'Ramapo',
Triploid 'Ramolet',
Triploid 'Veesprite',
Tetraploid Rhododendron augustinii,
Tetraploid Rhododendron minus var. minus 'Epoch'

Source: Kristian Theqvist

John and Sally Perkins

'Veesprite' is a Triploid

2011-11-23T08:55:00.000-08:00

Rhododendron 'Veesprite', which is a Forster hybrid documented as Rhododendron impeditum x Rhododendron racemosum, 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.

Summary of Ploidy Levels

Diploid Rhododendron minus,
Diploid Rhododendron racemosum,
Triploid 'Angel Powder',
Triploid 'April Rhapsody',
Triploid 'Bluenose',
Triploid 'Evening Sky',
Triploid 'Kehr's White Ruffles',
Triploid 'Purple Gem',
Triploid 'Ramapo',
Triploid 'Ramolet',
Triploid 'Veesprite',
Tetraploid Rhododendron minus var. minus 'Epoch'

Source: John and Sally Perkins

John and Sally Perkins

'Evening Sky' is a Triploid

2011-11-22T03:53:00.000-08:00

Rhododendron 'Evening Sky' 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.

Summary of Ploidy Levels

Diploid Rhododendron minus,
Diploid Rhododendron racemosum,
Triploid 'Angel Powder',
Triploid 'April Rhapsody',
Triploid 'Bluenose',
Triploid 'Evening Sky',
Triploid 'Kehr's White Ruffles',
Triploid 'Purple Gem',
Triploid 'Ramapo',
Triploid 'Ramolet',
Triploid 'Veesprite',
Tetraploid Rhododendron minus var. minus 'Epoch'

Source: John and Sally Perkins

John and Sally Perkins

'Ramolet' is a Triploid

2011-11-21T04:56:00.000-08:00

Rhododendron 'Ramolet', which is a Linc Foster hybrid documented as having 'Ramapo' as a seed parent, 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.

Summary of Ploidy Levels

Diploid Rhododendron minus,
Triploid 'April Rhapsody',
Triploid 'Bluenose',
Triploid 'Purple Gem',
Triploid 'Ramapo',
Triploid 'Ramolet'

Source: John and Sally Perkins

John and Sally Perkins

'Ramapo' is a Fertile Triploid

2011-11-20T06:00:00.000-08:00

Rhododendron 'Ramapo', which is a Guy Nearing hybrid documented as Rhododendron minus Carolinianum Group x Rhododendron fastigiatum, 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.

'Ramapo' is documented to be the seed parent of the triploid 'Ramolet'.

Summary of Ploidy Levels

Diploid Rhododendron minus,
Triploid 'April Rhapsody',
Triploid 'Bluenose',
Triploid 'Purple Gem',
Triploid 'Ramapo',
Triploid 'Ramolet'

Source: John and Sally Perkins

John and Sally Perkins

Beginner Rhododendrons

2011-11-20T05:25:00.000-08:00

A video showing beginner Rhododendrons.

http://www.youtube.com/watch?v=ToNIm1MBGCM&NR=1

Doing Crosses

2011-11-20T05:20:00.000-08:00

A video on how to do crosses with Joe Bruso.

http://www.youtube.com/watch?v=k3KLnw4YxiE

'Solidarity' OP is a Triploid

2011-11-19T13:43:00.000-08:00

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',
Triploid 'Solidarity' OP

Source: John and Sally Perkins

John and Sally Perkins

Rhododendron columbianum is a Diploid

2011-11-13T01:18:00.001-08:00

Rhododendron columbianum has been determined to be a diploid 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 columbianum is often documented as being a hybrid between Rhododendron groenlandicum and Rhododendron neoglandulosum. Since Rhododendron groenlandicum and Rhododendron neoglandulosum are tetraploid, Rhododendron columbianum, being diploid, is most likely a separate species.

Summary of Ploidy Levels

Diploid Rhododendron columbianum,
Diploid Rhododendron subarticum,
Diploid Rhododendron subulatum China,
Tetraploid Rhododendron diversipilosum,
Tetraploid Rhododendron diversipilosum 'Milky Way',
Tetraploid Rhododendron groenlandicum,
Tetraploid Rhododendron groenlandicum Saco Bog, Maine,
Tetraploid Rhododendron hypoleucum,
Tetraploid Rhododendron neoglandulosum,
Tetraploid Rhododendron tolmachevii,
Tetraploid Rhododendron tomentosum Turku Archipelago

Source: Kristian Theqvist
Source: Hans Eiberg
Source: Robert MacIntyre

John and Sally Perkins

Rhododendron tolmachevii is a Tetraploid

2011-11-12T01:40:00.000-08:00

Rhododendron tolmachevii has been determined to be a tetraploid 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

Summary of Ploidy Levels

Diploid Rhododendron columbianum,
Diploid Rhododendron subarticum,
Diploid Rhododendron subulatum China,
Tetraploid Rhododendron diversipilosum,
Tetraploid Rhododendron diversipilosum 'Milky Way',
Tetraploid Rhododendron groenlandicum,
Tetraploid Rhododendron groenlandicum Saco Bog, Maine,
Tetraploid Rhododendron hypoleucum,
Tetraploid Rhododendron neoglandulosum,
Tetraploid Rhododendron tolmachevii,
Tetraploid Rhododendron tomentosum Turku Archipelago

Source: Kristian Theqvist
Source: John and Sally Perkins

John and Sally Perkins

Rhododendron neoglandulosum is a Tetraploid

2011-11-11T01:38:00.000-08:00

Rhododendron neoglandulosum has been determined to be a tetraploid 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

Summary of Ploidy Levels

Diploid Rhododendron columbianum,
Diploid Rhododendron subarticum,
Diploid Rhododendron subulatum China,
Tetraploid Rhododendron diversipilosum,
Tetraploid Rhododendron diversipilosum 'Milky Way',
Tetraploid Rhododendron groenlandicum,
Tetraploid Rhododendron groenlandicum Saco Bog, Maine,
Tetraploid Rhododendron hypoleucum,
Tetraploid Rhododendron neoglandulosum,
Tetraploid Rhododendron tolmachevii,
Tetraploid Rhododendron tomentosum Turku Archipelago

Source: Kristian Theqvist

John and Sally Perkins

Rhododendron hypoleucum is a Tetraploid

2011-11-10T03:16:00.000-08:00

Rhododendron hypoleucum has been determined to be a tetraploid 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

Summary of Ploidy Levels

Diploid Rhododendron columbianum,
Diploid Rhododendron subarticum,
Diploid Rhododendron subulatum China,
Tetraploid Rhododendron diversipilosum,
Tetraploid Rhododendron diversipilosum 'Milky Way',
Tetraploid Rhododendron groenlandicum,
Tetraploid Rhododendron groenlandicum Saco Bog, Maine,
Tetraploid Rhododendron hypoleucum,
Tetraploid Rhododendron neoglandulosum,
Tetraploid Rhododendron tolmachevii,
Tetraploid Rhododendron tomentosum Turku Archipelago

Source: Kristian Theqvist

John and Sally Perkins

Rhododendron diversipilosum is a Tetraploid

2011-11-09T16:35:00.000-08:00

Rhododendron diversipilosum has been determined to be a tetraploid 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 diversipilosum was formerly classified as Ledum palustre var. diversipilosum.

Summary of Ploidy Levels

Diploid Rhododendron columbianum,
Diploid Rhododendron subarticum,
Diploid Rhododendron subulatum China,
Tetraploid Rhododendron diversipilosum,
Tetraploid Rhododendron diversipilosum 'Milky Way',
Tetraploid Rhododendron groenlandicum,
Tetraploid Rhododendron groenlandicum Saco Bog, Maine,
Tetraploid Rhododendron hypoleucum,
Tetraploid Rhododendron neoglandulosum,
Tetraploid Rhododendron tolmachevii,
Tetraploid Rhododendron tomentosum Turku Archipelago

Source: Kristian Theqvist

John and Sally Perkins

Rhododendron groenlandicum Saco Bog is a Tetraploid

2011-11-08T03:18:00.000-08:00

Rhododendron groenlandicum Saco Bog has been determined to be a tetraploid 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 groenlandicum was formerly classified as Ledum groenlandicum.

Summary of Ploidy Levels

Diploid Rhododendron columbianum,
Diploid Rhododendron subarticum,
Diploid Rhododendron subulatum China,
Tetraploid Rhododendron diversipilosum,
Tetraploid Rhododendron diversipilosum 'Milky Way',
Tetraploid Rhododendron groenlandicum,
Tetraploid Rhododendron groenlandicum Saco Bog, Maine,
Tetraploid Rhododendron hypoleucum,
Tetraploid Rhododendron neoglandulosum,
Tetraploid Rhododendron tolmachevii,
Tetraploid Rhododendron tomentosum Turku Archipelago

Source: Saco Bog, Maine (John and Sally Perkins)

John and Sally Perkins

Reminder: Board Meeting @ Wed Nov 9 7:30pm - 9pm (ARS Massachusetts Chapter Calendar)

2011-11-07T16:30:00.001-08:00

more details »

Board Meeting

When

Wed Nov 9 7:30pm – 9pm Eastern Time

Where

Hardings (map)

Calendar

ARS Massachusetts Chapter Calendar

Who

•	John Perkins - creator

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Rhododendron tomentosum Turku Archipelago is a Tetraploid

2011-11-07T06:29:00.000-08:00

Rhododendron tomentosum Turku Archipelago has been determined to be a tetraploid 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 tomentosum was formerly classified as Ledum.

Summary of Ploidy Levels

Diploid Rhododendron columbianum,
Diploid Rhododendron subarticum,
Diploid Rhododendron subulatum China,
Tetraploid Rhododendron diversipilosum,
Tetraploid Rhododendron diversipilosum 'Milky Way',
Tetraploid Rhododendron groenlandicum,
Tetraploid Rhododendron groenlandicum Saco Bog, Maine,
Tetraploid Rhododendron hypoleucum,
Tetraploid Rhododendron neoglandulosum,
Tetraploid Rhododendron tolmachevii,
Tetraploid Rhododendron tomentosum Turku Archipelago

Source: Kristian Theqvist

John and Sally Perkins

Cross of the Year 2011

2011-11-06T14:55:00.000-08:00

The Founders Day Dinner featured a talk from Steve Hootman on his trips to China.

The 2011 Cross of the Year were as follows:

Rhododendron calendulaceum 'Cherokee' X 'Lady Roseberry'
'Hachmann's Polaris' X 'Olin O'Dobbs'
(vernicosum X smirrnowii) X 'Point Defiance'

Don Brophy, Doug and Susan Harding, and Joe Bruso each received a seedling that had been ploidy tested by the Portugal based research team. The seedlings were as follows:

[Rhododendron calendulaceum "Skinner #166' X Rhododendron calendulaceum'Cherokee'] (Tested as 4X)
[viscosum glaucum not X Rhododendron calendulaceum 'Smoky Mountaineer'] (Tested as 3X)
[(prunifolium X arborescens) X Rhododendron calendulaceum 'Smoky Mountaineer'] (Tested as 3X)

Every one at the dinner was given a seedling of the following:

Rhododendron calendulaceum "Skinner #166' X Rhododendron calendulaceum'Cherokee'

These seedlings were grown on by

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

Cross of the Year for 2010

'Marydel' X R. calendulaceum 'Smokey Mountaineer'
['Hachmann's Polaris' X ('Scarlet Romance' X 'Red Bomber')]

Cross of the Year for 2009

'Marydel' X R. colemanii
'Vinecrest' X 'Planeta'

Reminder: Founder's Day Brunch @ Sun Nov 6 11:30am - 3pm (ARS Massachusetts Chapter Calendar)

2011-11-04T09:30:00.001-07:00

more details »

Founder's Day Brunch

Steve Hootman Talk
Brunch, Seed Exchange

When

Sun Nov 6 11:30am – 3pm Eastern Time

Where

Papa Razzi, Wellesley, MA (map)

Calendar

ARS Massachusetts Chapter Calendar

Who

•	john.a.perkins@gmail.com - creator

Invitation from Google Calendar

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You can change your reminders for specific events in the event details page in https://www.google.com/calendar/.

Rhododendron luteum Yellow form is a Tetraploid

2011-11-04T06:33:00.000-07:00

Rhododendron luteum Yellow form has been determined to be a tetraploid 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 luteum was also determined to be a tetraploid using flow cytometry by Dr. Thomas Ranney, J.R. Jones, and Nathan Lynch.

Summary of Ploidy Levels

Tetraploid Rhododendron luteum,
Tetraploid Rhododendron luteum 'Golden Comet',
Tetraploid Rhododendron luteum Orange form,
Tetraploid Rhododendron luteum Yellow form

Source: Kristian Theqvist

John and Sally Perkins

Rhododendron luteum Orange form is a Tetraploid

2011-11-03T05:15:00.000-07:00

Rhododendron luteum Orange form has been determined to be a tetraploid 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 luteum was also determined to be a tetraploid using flow cytometry by Dr. Thomas Ranney, J.R. Jones, and Nathan Lynch.

Summary of Ploidy Levels

Tetraploid Rhododendron luteum,
Tetraploid Rhododendron luteum 'Golden Comet',
Tetraploid Rhododendron luteum Orange form,
Tetraploid Rhododendron luteum Yellow form

Source: Kristian Theqvist

John and Sally Perkins

Reminder: Board Meeting @ Wed Nov 9 7:30pm - 9pm (ARS Massachusetts Chapter Calendar)

2011-11-02T17:30:00.001-07:00

more details »

Board Meeting

When

Wed Nov 9 7:30pm – 9pm Eastern Time

Where

Hardings (map)

Calendar

ARS Massachusetts Chapter Calendar

Who

•	john.a.perkins@gmail.com - creator

Invitation from Google Calendar

You are receiving this email at the account john.a.perkins@gmail.com because you set a reminder for this event on the calendar ARS Massachusetts Chapter Calendar.

You can change your reminders for specific events in the event details page in https://www.google.com/calendar/.

'Django' is a Triploid

2011-11-02T07:10:00.000-07:00

Rhododendron 'Django', which is a Hachmann hybrid documented as 'Abendglut' x Rhododendron brachycarpum ssp tigerstedtii, 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.

Summary of Ploidy Levels

Triploid 'Django'

Source: Kristian Theqvist

John and Sally Perkins

'Lilac Lights' is a Diploid

2011-11-01T07:50:00.000-07:00

Rhododendron 'Lilac Lights', which is in the Northern Lights group from the University of Minnesota documented as Rhododendron canadense X Rhododendron molle hybrid, has been determined to be a diploid 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.

Summary of Ploidy Levels

Diploid Rhododendron canadense,
Diploid Rhododendron molle,
Diploid Rhododendron prinophyllum,
Diploid 'Frank Abbott',
Diploid 'Jane Abbott',
Diploid 'Lilac Lights',
Diploid 'Orchid Lights',
Diploid 'Rosy Lights',
Triploid 'Spicy Lights',
Triploid 'White Lights',
Tetraploid Rhododendron atlanticum,
Tetraploid Rhododendron calendulaceum,
Tetraploid Rhododendron luteum,
Tetraploid 'Apricot Surprise',
Tetraploid 'Candy Lights',
Tetraploid 'Golden Lights',
Tetraploid 'Lemon Lights',
Tetraploid 'Mandarin Lights',
Tetraploid 'Northern Hi-Lights',
Tetraploid 'Tri-Lights'

Source: Kristian Theqvist

John and Sally Perkins

Reminder: Founder's Day Brunch @ Sun Nov 6 11:30am - 3pm (ARS Massachusetts Chapter Calendar)

2011-10-30T09:30:00.001-07:00

more details »

Founder's Day Brunch

Steve Hootman Talk
Brunch, Seed Exchange

When

Sun Nov 6 11:30am – 3pm Eastern Time

Where

Papa Razzi, Wellesley, MA (map)

Calendar

ARS Massachusetts Chapter Calendar

Who

•	john.a.perkins@gmail.com - creator

Invitation from Google Calendar

You are receiving this email at the account john.a.perkins@gmail.com because you set a reminder for this event on the calendar ARS Massachusetts Chapter Calendar.

You can change your reminders for specific events in the event details page in https://www.google.com/calendar/.

'Rosy Lights' is a Diploid

2011-10-28T09:11:00.000-07:00

Rhododendron 'Rosy Lights', which is in the Northern Lights group from the University of Minnesota documented as Rhododendron prinophyllum X Rhododendron molle, has been determined to be a diploid 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.

Summary of Ploidy Levels

Diploid Rhododendron canadense,
Diploid Rhododendron molle,
Diploid Rhododendron prinophyllum,
Diploid 'Frank Abbott',
Diploid 'Jane Abbott',
Diploid 'Lilac Lights',
Diploid 'Orchid Lights',
Diploid 'Rosy Lights',
Triploid 'Spicy Lights',
Triploid 'White Lights',
Tetraploid Rhododendron atlanticum,
Tetraploid Rhododendron calendulaceum,
Tetraploid Rhododendron luteum,
Tetraploid 'Apricot Surprise',
Tetraploid 'Candy Lights',
Tetraploid 'Golden Lights',
Tetraploid 'Lemon Lights',
Tetraploid 'Mandarin Lights',
Tetraploid 'Northern Hi-Lights',
Tetraploid 'Tri-Lights'

Source: Kristian Theqvist

John and Sally Perkins

'Spicy Lights' is a Triploid

2011-10-27T04:02:00.000-07:00

Rhododendron 'Spicy Lights', which is in the Northern Lights group from the University of Minnesota documented as Rhododendron prinophyllum as the seed parent, 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 'Spicy Lights' appears to be sterile.

Summary of Ploidy Levels

Diploid Rhododendron canadense,
Diploid Rhododendron molle,
Diploid Rhododendron prinophyllum,
Diploid 'Lilac Lights',
Diploid 'Orchid Lights',
Diploid 'Rosy Lights',
Triploid 'Spicy Lights',
Triploid 'White Lights',
Tetraploid Rhododendron atlanticum,
Tetraploid Rhododendron calendulaceum,
Tetraploid Rhododendron luteum,
Tetraploid 'Apricot Surprise',
Tetraploid 'Candy Lights',
Tetraploid 'Golden Lights',
Tetraploid 'Lemon Lights',
Tetraploid 'Mandarin Lights',
Tetraploid 'Northern Hi-Lights',
Tetraploid 'Tri-Lights'

Source: Kristian Theqvist

John and Sally Perkins

Founders' Day reminder

2011-10-25T12:42:00.000-07:00

The deadline for reservations for our Founders' Day lunch is this Friday, October 29. In addition to good food and great company, this year we have the real pleasure of hearing Steve Hootman, Director and Curator of the Rhododendron Species Garden, who will give us a spectacular travelogue of his most recent trip to China and Vietnam.

Give our treasurer, Pete LIttlefield a call or email to let him know your check for the lunch is in the mail. 508.429.6470 email woodland.gardener@verizon.net

=====================================================================

Founders' Day BRunch

Sunday November 6 Note the early date

PAPA RAZZI WELLESLEY 11:30 Am

We will have our brunch again at the Wellesley Papa Razzi at 16 Washington St., Wellesley, at 11:30. Papa Razi is just off Route 128 (I-95) at Route 16, heading west. The menu, like last year's, sounds delicious: fresh fruit platter, assorted breakfast breads, green salad, chicken, pasta, scrambled eggs, bacon, roasted vegetables, and coffee and tea.

We are bringing our Dick Brooks Memorial Speaker all the way from the west coast. Steve Hootman, the Executive Director and Curator of the Rhododendron Species Botanical Garden, will speak to us about "Plant Hunting in South –Central China and Northern Vietnam: A New Frontier." He will discuss the landscapes, culture, and flora and show pictures from his last three expeditions to this region, which has become his primary focus for the past several years. This should be a great travelogue by one of the rhododendron world's great modern plant explorers.

We will also have our annual Seed Exchange. John Perkins has taken on the mantle of selecting and producing the Cross of the Year. If you have seed to contribute to the exchange, bring your labeled contributions in paper or glassine bags, not plastic bags [thanks Joe Bruso for emphasizing that].

Cost: $30 per person Reservations required

Reservations: send your check made out to ARSMC to:

Pete Littlefield, 75 Oak Street, Holliston, MA 01764 (508.429.6470 email woodland.gardener@verizon.net)

FDeadline for reservations

SATURDAY OCTOBER 29 E

We must give the restaurant the number of attendees before the brunch, so be sure to get your checks & reservations in to Pete Littlefield by the deadline.

Directions: This restaurant is easy to get to, less than a mile from 128/I95. Take Exit 21A off Route 128 (I-95) at Route 16 West. Merge shortly with Quinobequin Road. Turn left on Washington St./ Route 16 and the restaurant is on the left. 16 Washington St. Ample parking.

'White Lights' is a Triploid

2011-10-25T10:36:00.000-07:00

Rhododendron 'White Lights', which is in the Northern Lights group from the University of Minnesota documented as Rhododendron prinophyllum X white Exbury, 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 'White Lights' appears to be sterile.

Most Exbury deciduous azaleas are tetraploids.

Summary of Ploidy Levels

Diploid Rhododendron canadense,
Diploid Rhododendron molle,
Diploid Rhododendron prinophyllum,
Diploid 'Lilac Lights',
Diploid 'Orchid Lights',
Diploid 'Rosy Lights',
Triploid 'Spicy Lights',
Triploid 'White Lights',
Tetraploid Rhododendron atlanticum,
Tetraploid Rhododendron calendulaceum,
Tetraploid Rhododendron luteum,
Tetraploid 'Apricot Surprise',
Tetraploid 'Candy Lights',
Tetraploid 'Golden Lights',
Tetraploid 'Lemon Lights',
Tetraploid 'Mandarin Lights',
Tetraploid 'Northern Hi-Lights',
Tetraploid 'Tri-Lights'

Source: Kristian Theqvist

John and Sally Perkins

Weighing In: Discovering the Ploidy of Hybrid Large Leaf Elepidote Rhododendrons

2011-10-21T01:06:00.000-07:00

Weighing In

When we mention the word ploidy most gardeners' eyes glaze over. What does ploidy have to do with their beautiful garden specimens of rhododendrons?

Yet if we mention 'Cynthia', 'Gomer Waterer', 'Grace Seabrook', 'Horizon Monarch', 'Marinus Koster', 'Pink Pearl', 'Phyllis Korn', 'Point Defiance', 'Taurus', or 'Trude Webster', gardeners quickly add that these are among their favorite rhododendrons or high on their wish list. Yes, these Rhododendrons display "something different" and "highly desirable."

As dozens more Rhododendrons with larger than normal ploidy levels are revealed below, we hope gardeners see the connection with characteristics of thickness in the leaf and firmness in flower substance. Indeed, remarkable vigor and substance overall, coupled with outstanding floral performance at a young age, starts to make sense. Even gardeners, who do not want to talk about ploidy, love talking about polyploids.

We are not geneticists. We do have science backgrounds with a passion for knowledge. Our ploidy journey began as simple curiosity combined with a willingness to coordinate with others, scour the Rhododendron literature and the web, and do some field work leading to more discoveries than we ever imagined.

First, when we refer to ploidy we mean the size of the genetic material of the plant. Genetic material is, in seed bearing plants, the genetic material found in the nucleus of the cell packed into structures called chromosomes.

There are 2 different techniques used to determine how much genetic material is in a cell and therefore, an estimate of the number of chromosomes that are present in the cell. One can count the ways or weigh the counts.

Count the ways: The classic way to determine the number of chromosomes in a plant is to visualize the chromosomes with stain when they are actively growing, as in a root tip, and then count the different pairs under the microscope. Reports are that this is very tedious, more so in rhododendrons, prone to error, and even eager graduate students are reluctant to cooperate. There are very few studies, mostly older, and even less duplication of results.

Weigh the counts: With the technique of flow cytometry it is possible to weigh the genetic material by taking healthy plant tissue and measuring the weight of the genetic material. This technique is much less time consuming and therefore easier to verify by duplicating results. Flow cytometry was developed to detect mutations in tumors and cancer cells. If the cells are normal and growing there would be a small number of cells with double the weight of their chromosomes as they would be in the phase prior to division. Any cells with less than or more than that weight would be an indication of mutations of the amount of genetic material in the cell (i.e. cancer). This valuable technique can also be used to detect the normal weight of genetic material in different species and hybrids of rhododendrons.

Polyploidy: Beginning with 1, 2, 3, 4, 5

In most plant cells, i.e. leaves, stems, roots and some parts of the flower; the chromosomes are paired with a matching chromosome to form the diploid state. We say most cells because when it comes time to reproduce, the unfertilized seed and the pollen are formed by the splinting apart of the paired chromosomes forming a nucleus with a single set of chromosomes; the unpaired or haploid state. And just to make things complicated true seeds have extra diploid tissue from the seed parent which merges with a haploid pollen nucleus to form the endosperm of a seed. The fertilized endosperm therefore has 3 sets of chromosome (2 from the seed mother and one from the pollen father) and is triploid. This extra genetic material nourishes the germinating seedling.

Most Rhododendrons get one set of chromosomes, denoted as 1x, from each parent (female and male) resulting in two sets of chromosomes, are commonly referred to as diploids, and denoted as 2x (1x + 1x = 2x). However some Rhododendrons have four sets of chromosomes, are commonly referred to as tetraploids, and denoted as 4x (2x + 2x = 4x). Triploids have three sets of chromosomes and are denoted 3x. Pentaploids have five sets of chromosomes and are denoted 5x. Rhododendrons having more than two sets of chromosomes are referred to as polyploids. [reference]

Although most Rhododendron species are diploids, tetraploid Rhododendron species exist [reference]. Individual triploid Rhododendrons, appearing to be hybrids, sometimes occur naturally where diploid and tetraploid species of Rhododendron are co-located. [reference]

Discovering: the Journey

In the fall of 1989, our Rhododendron polyploidy journey unknowingly started when we overheard at a local Rhododendron meeting a statement Frank Mossman wrote in 1972 concerning his hybridization efforts with Rhododendron occidentale: [reference]

"We have found that Rhododendron occidentale will cross with many other rhododendrons or azaleas if Rhododendron occidentale is the seed parent, but Rhododendron occidentale as a pollen parent produces few seed."

We wondered why.

In the fall of 2011, we uncovered that in 1972 Harold Greer wrote the following concerning his hybridization with 'Countess of Derby' to produce 'Trude Webster': [reference]

"If you are one of those who feels that there could be nothing outstanding produced in a pink rhododendron I would have been the first to agree with you. That was until I saw the first bud unfold on the original seedling of R. 'Countess of Derby' selfed."

Both Mossman and Greer had encountered the wonder accompanying the many puzzles presented by polyploid Rhododendrons, so we were in good company.

Starting in the early 1990's, we unknowingly crossed deciduous azalea involving different ploidy levels leading in 2010 to collecting samples of diploid, triploid, and tetraploid Rhododendrons for ploidy testing at the University of Coimbra in Portugal. Each step on this pathway revealed more about the wonderful world of ploidy in our own Rhododendron garden.

Below is a summary of what we discovered, often based on the research, observations, and documentation of many others, about the ploidy of hybrid large leaf elepidote Rhododendrons and the people encountered on our slow but wondrous journey.

Figure 1: Generational Breeding of Polyploid Hybrid Elepidotes

The ploidy of named hybrid large leaf elepidote Rhododendrons as determined 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

unless otherwise indicated.

Summary of Ploidy

2x Diploids

1000 Butterflies
Alice
Anna (Lem, 1952) U
Betty Hume
Bibiani
Cheyenne *
Colonel Coen
Countess of Athlone
Diane
Duke Of York
Elegans
Everlasting *
Fantastica *
Furnivall's Daughter
Gillii
Gill's Triumph
Goldflimmer *
Goldsworth Orange #
Graf Zeppelin (van Nes, 1934) P
Horizon Lakeside
Hotei
Hurricane (Whitney, 1960) P
Isabel Pierce
Janet Blair *
J.G. Millais (Waterer, 1915) P
Jingle Bells #
Kathy Van Veen
Kristian's Pink
Kupferberg #
Lady Bligh
Lady de Rothchild
Lady Eleanor Cathcart
Lavendelmilch
Lem's Cameo
Loderi Venus
Madame Carvalho
Maxicat *
maximum Kalamity
Mindy’s Love
Mother of Pearl (sport, 1925) P
Mrs A. T. De la Mare
Mrs Lindsay Smith
Mrs. Furnival
Nancy Evans
Naselle
Norman Gill
Nova Zembla *
Olin O. Dobbs
Orange Leopard (Brack, 1988) P S
Peach Charm
Peach Recital (Barlup, 1996) P
Phipps Yellow
Pink Prelude
Polar Bear *
Puget Sound *
Red Olympia
Rendezvous (Hachmann, 1968) P S
Stony Brook (Brack, 1988) P S
Summer Peach (Barlup, 1988) P
Summer Wind (Barlup, 1996) P
The Honourable Jean Marie de Montague (van Nes, 1901) U
Viscy #
Voluptuous
Vulcan *
Vulcan’s Flame *
White Pearl syn Halopeanum
Wild Affair

3x Triploids

Anita Gehnrich (Gehnrich) UM
Anna Rose Whitney (Van Veen, 1954) F NM
August Lamken (Hobbie, 1942)
Beauty of Littleworth (Mangles, 1884)
Betty Wormald (Koster, 1907) F
Broughtonii (Broughton, 1840) F
Cotton Candy (Henny and Wennekamp, 1958) F UM
Cynthia (Standish and Noble, 1856) F
Dame Nellie Melba (Loder, 1926)
Ebony Pearl (sport, 1966)
Django (Hachmann 1985)
El Camino (Whitney, 1976) NM
Gartendirektor Rieger (Hobbie, 1947)
Gomer Waterer (Waterer, 1900) F DM
Grace Seabrook (Seabrook, 1965) UM
Hallelujah (Greer, 1958)
Hank's Folly (Schannen) NM
Julia Caroline (Brockenbrough, 1990) NM
Lady of Spain (Lofthouse, 1966) NM
Lucky Strike (Van Veen, 1958) NM
Lydia (Greer, 1963) F NM
Markeeta's Flame (Markeeta, 1960) UM
Markeeta's Prize (Markeeta, 1970) UM
Opal Thornton (Thornton) NM
Pearce's American Beauty (Pearce, 1930) F
Phyllis Korn (Korn, 1969) F DM
Pink Pearl (Waterer, 1892) F DM
Platinum Pearl (Greer, 1983) F NM
Rothenburg (von Martin, 1944)
Rwain (Colombel, 1993) F NM
Solidarity (Schannen, 1969) F UM
Steredenn (Colombel) NM
Sugar Pink (Greer, 1960) NM
Super Dog (Bones) NM
Taurus (Mossman, 1962) F UM
Topsvoort Pearl (sport, 1935)
Val d'Aulnay (Croux and Fils, 1984) F
Van (Van Veen, 1930) NM

4x Tetraploids

Antoon van Welie (Endtz, 1930) 3X2
Brigg's Red Star (Briggs) T
Cherry Cheesecake (Briggs) T *
Countess of Derby (White, 1913) 3X3
diaprepes Gargantua (Stevenson, 1923)
Doreen Gale (Sanders) 4X4
Gentle Giant (Sanders, 1992) 4X3
Gorgeous George (Sanders) 4X4
Grand Slam (Greer, 1982) 4X3
Horizon Jubilee (Brockenbrough) *
Horizon Monarch (Brockenbrough, 1981) 2X4
Le Fouesnantais (Colombel, 1997) 4XQ
Legend (Barlup) 4X4
Lem's Monarch syn Pink Walloper (Lem, 1965) 2X4
L'Engin (de la Sablière) 4X2
Marinus Koster (Koster, 1937)
Point Defiance (Lem, 1970) 2X4
Summer Joy (Kehr) T
Super Nova (Briggs) T *
Trude Webster (Greer, 1960) 4x4
Very Berry (Greer, 1988) 4X2

F indicates a fertile triploid.
T indicates a chemically induced tetraploid.
P indicates a diploid with a polyploid ancestor.
S indicates a diploid with a tetraploid parent.
U indicates a diploid with a tendency to produce unreduced gametes.
DM indicates a triploid resulting from a triploid parent.
NM indicates a triploid resulting from a tetraploid parent.
UM indicates a triploid resulting from 2 diploid parents.
2X4 or 4X2 indicates a tetraploid resulting from a diploid and a tetraploid parent.
3X2 indicates a tetraploid resulting from a triploid and a diploid parent.
3X3 indicates a tetraploid resulting from 2 triploids parents.
4X4 indicates a tetraploid resulting from 2 tetraploid parents.
4X3 indicates a tetraploid resulting from a tetraploid and a triploid parent.
4XQ indicates a tetraploid resulting from a tetraploid parent.
* indicates flow cytometry ploidy testing was done by research team lead by Dr. Ranney.
# indicates flow cytometry ploidy testing was done by Tom Eeckhaut.
(,) indicates the name of the hybridizer and date of cross.

Noteworthy is the named form diaprepes 'Gargantua'. There is no evidence that the species diaprepes is tetraploid. ONLY the named form 'Gargantua' has tested as tetraploid. To date, no large leaf elepidote species as a population has tested as tetraploid, but this could change.

For a brief history on how a few of these named polyploid elepidotes evolved read It is a Beautiful Spring Day in 1913 so What Do You Do? See figure 1 above.

Historical evidence indicates that by 1910 the triploids 'Betty Wormald', 'Beauty of Littleworth', 'Broughtonii', 'Cynthia', 'Gomer Waterer', 'Pink Pearl' would have been on most peoples' lists of best large leaf Rhododendrons.

In 1958, George Grace's list of best large leaf Rhododendrons included all but one of these triploids plus the tetraploids 'Countess of Derby' and 'Marinus Koster'.

In 2008, the Siuslaw Chapter of American Rhododendron Society included on their list of best large leaf Rhododendrons the triploids 'Cynthia', 'Dame Nellie Melba', 'Grace Seabrook', and 'Taurus', and the tetraploids 'Grand Slam', 'Lem's Monarch', 'Horizon Monarch', 'Point Defiance', and 'Very Berry'.

By 2011, examination of rhododendrons of the year, proven performers, [2], [3], [4], [5], [6], [10], [11], Award of Garden Merit and best in show trusses adds to the "bests" mentioned above the triploids 'Anita Gehnrich', 'Anna Rose Whitney', 'Cotton Candy', 'Ebony Pearl', 'Gartendirektor Rieger', 'Hallelujah', 'Markeeta’s Prize', 'Platinum Pearl', 'Solidarity', and 'Super Dog' and the tetraploids 'Gentle Giant' and 'Trude Webster'.

'Pink Pearl' won the first Award of Merit in 1897 and was selected Rhododendron of the Year in 2006 by the Southwestern Chapter of the American Rhododendron Society. In 1950, a large 'Cynthia', bred in 1858, was the first Rhododendron planted in the Crystal Springs Rhododendron Garden. 'Trude Webster' won American Rhododendron Society's first Superior Plant Award in 1971 and is still found on lists of proven performers for the west coast. 'Broughtonii', bred in 1840, is still considered to be among the best warm weather Rhododendrons according to Burke who gardens in Australia.

In other words, over twenty-five of the fifty or so confirmed polyploid large leaf Rhododendrons have appeared on lists of the best Rhododendrons and once these polyploids appear on such lists they tend to make future such "best" lists.

The following hybridizers have worked with or produced polyploid elepidotes hybrids:

Barlup
Bones
Boulter
Bovees
Brack
Briggs
Brockenbrough
Broughton
Bruns
Colombel
Croux and Fils
de la Sablière
Drake
Elliott
Endtz
Evans
Farewell
Felix and Dijkhuis
Fennichia
Fujioka
Gill
Greer
Gehnrich
Hachmann
Hall
Hartman
Heinje
Henny and Wennekamp
Hobbie
Horlick
Horsley
Johnson
Kavka
Kehr
Korn
Koster
Larson
Laxdall
Lem
Loder
Lofthouse
Mangles
Markeeta
McCullough
Moynier
Mossman
Murcott
Naylor
Ostler
Patterson
Pearce
Perkins
Rabideau
Ragans
Reuthe
Sanders
Schannen
Seabrook
Shapiro
Smith
Standish and Noble
Stead
Stevenson
Stockman
Thacker
Thornton
van Nes
Van Veen
Vinson
von Martin
Walton
Waterer
White
Whitney
Wilson
Winberg and Smith
Woodward

Noteworthy is that more hybridizers have worked with confirmed large leaf elepidote polyploids than there are such confirmed polyploids. More importantly, some of the hybridizers on this list are best known for the polyploid elepidotes they have created. In fact, in a few instances polyploid elepidotes have been named in honor of a wife, a mother, or a grandparent.

By the way, Mossman working with the diploid deciduous azalea species Rhododendron occidentale discovered what Barlup later discovered working with hybrid elepidotes: diploids are much more likely to accept pollen from tetraploids than tetraploids are to accept pollen from diploids. Our Rules of Engagement addresses this topic in detail.

Jim Barlup wrote the following about using polyploid large leaf elepidotes as parents: [reference]

"I continue to test the pollen and plants which I doubt for 3 or 4 years to determine their fertility or sterility. If you cross a diploid with tetraploid pollen you can achieve beautiful seedpods but their germination is very difficult. 3% seed germination for 'Point Defiance'. Obtained are both diploid or tetraploid offspring."

Breeding with polyploid large leaf elepidotes is not an easy task which explains why so few polyploids have been created to date despite so many hybridizers having attempted to use them as parents.

Ron Naylor wrote the following about his best plant, 'Francis Augustus Storey', from a cross involving 'Point Defiance': [reference]

"'Francis Augustus Storey' - Best of grex of four plants from weak germination. One died in 2000 and another in 2001."

Dick Murcott wrote the following about the plant he calls 'TT116': [reference]

"TT116 – [('Jean Marie' x R. yakushimanum) x 'Grand Slam']. Only one seed from this cross germinated. Looks like a tetraploid. Pink. Looks like 'Trude Webster' but is definitely a seedling."

Barlup, Murcott, and Naylor each encountered both the wonder and puzzles presented by polyploid Rhododendrons.

We have discovered for deciduous azaleas that seed produced from tetraploid X tetraploid normally has high rates of germination but germination from diploid X tetraploid crosses varies greatly but is normally low.

To read about Frank Abbott's encounter with the wonders of working with deciduous azaleas of different ploidy levels see Frank Abbott's Village of Azaleas or 'Margaret Abbott' is a Tetraploid.

The following people and organizations donated samples for this research:

John Abbott,
Vivian Abney of East Fork Nursery,
Living Collection of Arnold Arboretum,
Natural Collection of Audra State Park,
Living Collection of Bartlett Arboretum,
Jim Barlup,
Bruce Clyburn,
Jane Brooks,
Joe Bruso,
Werner Brack,
Ned Brockenbrough,
Natural Collection of Canobie Lake, NH,
Dick Cavender,
Living Collection of Connecticut College Arboretum,
Marc Colombel,
Mike Creel,
Al Fitzburg,
Robert Fox,
Harold Greer of Greer Gardens,
George Hibben,
Living Collection of Highstead Arboretum,
Don Hyatt,
Lindy Jackson of Appalachian Native Plants,
Richard Jaynes of Broken Arrow Nursery,
Doug Jolley,
Fred Knippel,
Living Collection of Longwood Gardens,
Ron Miller,
Dick Murcott,
Michael Medeiros of Planeview Nursery, Portsmouth, RI
John and Sally Perkins,
Ron Rabideau of RareFind Nursery,
Ellie Sather of Whitney Gardens,
Natural Collection of Stoddard Blog, NH,
>Kristian Theqvist,
John Thornton,
Hendrik Van Oostand of Azaleatuin,
Kathy Van Veen of Van Veen Nursery

We wish to thank everyone who donated samples for this research.

Named Elepidotes Suspected of being Polyploid:

Adriaan Koster
Aggie
Aibette
Alibaby
Annie E. Endtz
Arden Primrose
Ariel Sherman
Aristide Briand
Arnold Piper *
Arthur Ostler
Babar
Bellevue
Bernard Crisp
Bernard Shaw
Boskoop Concorde
Bruns Sirius
Canadian Beauty *
Cara Meg
Caruso
Castanets
Charis
Courtenay Duke
Dagmar
Denali
Diane Marie
Diane Titcomb
Direktor Siebert
Doctor A. Blok
Doctor Arnold W. Endtz
Doctor H.C. Dresselhuys
Don Juan
Donald Waterer
Doris Nolan
Double Drake
Dr. V.H. Rutgers
Edward Cornelius
Elizabeth Titcomb
Ester Grace
Eureka Maid
Fiona Wilson
Forever Violet
Fragrant Sensation *
Francis Augustus Storey *
Frentano
Friesland
Garnet
George Hardy
Germania *
Gill's Gloriosa
Goliath
Grab Ya *
Gunborg
Gwen Bell
Hachmann's Anastasia
Hachmann's Kristina
Haithabu
Halfdam Lem
Heat Wave
Heinje's Venezia
Helen Druecker
Hollandia
Horizon Serenity *
Ilam Apricot
Inheritance
Irmelies
Isadora
Isobel Baillie
Jan Dekens
Janet Ward
Jean Lennon
Jean Marie Variegated
Jeanne Yvonne
Jenice Coffey
Johnny Bender
Julie Titcomb
Justa Pink
Kareness
Kathe Heinje
Kathy Ann Pieries
Kay Too
KSW
Lady Longman
Leonardslee Giles
Lilian
Loder's White
Lou-John Gem
Newcomb's Sweetheart
Madah Jean
Margaret Mack
Marion
Mary-Ed
Maureen Ostler
Melville
Miss Kitty
Mistake
Mrs E C Stirling (sister of Pink Pearl)
Newcomb's Sweetheart
Nicandra Newman
Orrie Dillie
Patricia Jacobs *
Peggy Bannier
Pink Goliath
President Kennedy
Pride of Roseburg *
Princess Debiann
Professor Hugo de Vries
Professor J. H. Zaayer
Qualicum's Pride
Queen Mary
Record
Reverend Paul *
Red Walloper *
Rhododendron niveum
Robert Korn
Romilda
Rotha
Scandinavia
Seraphine
Shalom
Shari Laurel
Sheer Enjoyment *
Sierra Sunrise
Sigrid
Souvenier de Docotr S. Endtz
Standishii
Titness Belle
TT116
Twins Candy
Virgo *
Vonnie Stockman
Walküre
Walloper *
Whidbey Island
White Swan
William Avery *

Despite having created this suspected polyploid list, we believe that over 25% would not test as polyploid. 'Fragrant Sensation', 'Grab Ya', 'Pride of Roseburg', and 'Sheer Enjoyment' having both parents as tested tetraploids are almost certainly polyploids. We have marked using an * the dozen or so we think are the most likely (almost certainly) polyploids.

Most in this list are known to have at least one polyploid parent, be a sibling of a polyploid, or be a parent of one or more polyploids. However, both triploid and tetraploid hybrid large leaf elepidotes are known to be capable of producing diploid offspring when the other parent is a diploid. Many hybrids on our suspected polyploid list have one parent suspected of being a diploid. In other words, a diploid can have a polyploid parent or sibling. Moreover, two diploid parents can produce a polyploid offspring so having a polyploid offspring does not insure either parent is a polyploid.

If one excludes known or suspected polyploid hybrids listed above, creating a list of 100 suspected polyploid named elepidote hybrids, where more than 20% would test as polyploid, would be difficult. In fact, it is highly likely that most attempts at such a list of 100 named elepidote hybrids would include very few if any additional polyploids.

In other words, we speculate that nearly all (over 90%) named polyploid elepidotes hybrids named prior to this post appear in this single post. This is almost certainly the case for polyploid elepidotes hybrids named prior to 2000. The chances there were more than 200 polyploid elepidote hybrids named prior to 2000 are low. The chances there were more than 50 tetraploid elepidote hybrids named prior to 2000 are even lower.

Figure 2: Offspring from Triploids (Pink Pearl)

In short there are no rules of thumb for guessing the ploidy of the offspring for hybrid large leaf elepidotes if the parents are of mixed ploidy levels or either parent is a triploid or pentaploid.

Diploid X diploid will almost always (but not always) create diploid offspring.

Tetraploid X tetraploid will almost always (but not always) create tetraploid offspring.

However, diploid X tetraploid and tetraploid X diploid, which are normally associated with producing triploid offspring, are known to often produce a combination of diploids, triploids, and tetraploids when working with hybrid large leaf elepidotes.

Triploids, Fertile Triploids, and Triploids as the Progeny of Triploids

Triploids are normally believed to be produced by one of two mechanisms.

Two diploids can cross where one diploid parent instead of providing one set of chromosomes provides two resulting in an offspring that has 3 sets of chromosomes. This is commonly referred to as the unreduced mechanism for creating triploids.

Ploidy results suggest that triploids such as 'Anita Gehnrich', 'Grace Seabrook', 'Markeeta's Flame', 'Markeeta's Prize', 'Solaridity', and 'Taurus' were most likely created by this unreduced mechanism.

On the other hand, a diploid parent and a tetraploid parent can cross where the diploid parent provides one set of chromosomes and the tetraploid parent provides two sets of chromosomes resulting in an offspring with 3 sets of chromosomes. This is referred to as the normal meiosis interploidy mechanism for creating triploids.

Ploidy results suggest that triploids such as 'Anna Rose Whitney', 'Cotton Candy', 'El Camino', 'Hank's Folly', 'Julia Caroline, 'Lady of Spain', 'Lucky Strike', 'Lydia', 'Opal Thornton', 'Platinum Pearl', 'Rwain', 'Steredenn', 'Sugar Pink', 'Super Dog', and 'Van' were most likely created by this normal meiosis interploidy mechanism.

Triploids are commonly believed to always be sterile as both seed parents and pollen parents. Yet offspring are documented for triploids such as 'Anna Rose Whitney', 'Betty Wormald', 'Broughtonii', 'Cotton Candy', 'Cynthia', 'Gomer Waterer', 'Lydia', 'Pearce's American Beauty', 'Phyllis Korn', 'Pink Pearl', 'Platinum Pearl', 'Rwain', 'Solidarity', 'Taurus', and 'Val d'Aulnay'. See figure 1.

Triploids such as 'Pink Pearl', 'Phyllis Korn', 'Rwain', and 'Taurus' appear to be partially fertile as both seed and pollen parents. See figure 2.

In fact, triploids can be the progeny of triploids. Based on parental documentation, 'Broughtonii', 'Pink Pearl, 'Gomer Waterer', and 'Phyllis Korn' represent four consecutive generations of triploids. See figure 1.

Three sports of the triploid 'Pink Pearl' were ploidy tested. 'Ebony Pearl' and 'Topsvoort Pearl' tested as triploid whereas 'Mother of Pearl' tested as diploid. See figure 2.

Diploids can be the progeny of triploids. The diploids 'Graf Zeppelin', 'Hurricane', 'J.G. Millais', and 'Summer Peach' are documented to have a triploid parent. In the case of 'Graf Zeppelin', the triploid 'Pink Pearl' is documented as the seed parent. See figure 2. Although a diploid, 'Graf Zeppelin' exhibits characteristics often associated with named polyploids.

Tetraploids can be the progeny of triploids. 'Countess of Derby', a tetraploid, is documented to have 2 triploid parents, namely 'Pink Pearl' and 'Cynthia'. The tetraploids 'Antoon van Welie', 'Gentle Giant', and 'Grand Slam' are documented to have a triploid parent. In the case of 'Antoon van Welie', the triploid 'Pink Pearl' is documented as the seed parent. See figure 2.

Marc Colombel donated some of his suspected polyploid hybrid seedlings for testing. Noteworthy is that four seedlings of 'Rwain' X ‘L’Engin’ tested as tetraploid. 'Rwain' the seed parent, is a triploid. 'L'Engin', the pollen parent, is a tetraploid. Moreover, three seedlings of 'Horizon Monarch' X 'Rwain' tested as tetraploids but one seedling tested as triploid. 'Horizon Monarch' is a tetraploid.

Figure 2 suggests that a triploid parent, for instance 'Pink Pearl', can produce offspring that are diploids, triploids, and tetraploids. Figure 1 suggests that pentaploids are also possible from a triploid parent.

In the 1930's, C. J. Darlington showed that triploids could be fertile. Moreover Darlington confirmed a third mechanism for creating triploids. Darlington showed that during meiosis triploids chromosomes may split forming a bell-shaped curve distribution. This means that although there are a few cells formed with 1x and 2x chromosomes, most are closer to the midpoint of 1.5x. So in a few cases, a triploid parent can act as a diploid contributing 1 set of chromosomes or as a tetraploid contributing 2 sets of chromosomes.

Our ploidy results, when combined with the documentation of parentage, strongly suggest this third distributive meiosis mechanism does occur for fertile triploid large leaf elepidote Rhododendrons.

Hans Eiberg has determined in controlled lab experiments that for Rhododendrons hybrid triploid pollen is sometimes as viable as any hybrid diploid pollen.

Tetraploids and Diploids as the Progeny of Tetraploids

Tetraploids such as 'Doreen Gale', 'Gorgeous George', and 'Legend' have been created by the normal meiosis mechanism where both parents are tetraploids.

Tetraploids such as 'Horizon Monarch', 'Lem's Monarch', 'L'Engin', 'Point Defiance', and 'Very Berry' may have been created by the unreduced mechanism of a diploid parent with the other parent being a tetraploid.

Justin Ramsey's work with newly created neotetraploids suggests that such neotetraploids may experience irregular meiosis. Ramsey suggests that in some instances a neotetraploid may contribute only one set of chromosomes to the offspring. For the purposes of this article, we refer to this as the super-reduced mechanism.

Diploids such as 'Orange Leopard', 'Rendezvous', and 'Stony Brook' may have been created by this super-reduced mechanism. In the case of 'Rendezvous', the tetraploid 'Marinus Koster' is documented as the seed parent.

Noteworthy is that one seedlings of 'Horizon Monarch' open pollinated tested as diploid. The actual plant of 'Horizon Monarch' that was the parent of this particular diploid seedling tested as tetraploid. Other seedlings from the same seedpod tested as tetraploid.

Our ploidy results suggest that tetraploids may produce diploid, triploid, tetraploid, and pentaploid offspring.

To read more about the super-reduced mechanism visit Ploidy Reduction in Blackberries" by Kristine Naess or Cytogentics of Rhubus: Meiotic Instability in Some Higher Polyploids by Maxine Thompson.

Normal, Unreduced, Super-reduced, and Distributive Meiosis: By the Numbers

A diploid Rhododendron has 26 chromosomes. Normally a diploid Rhododendron as a parent splits in half contributing 13 chromosomes to the offspring.

A tetraploid Rhododendron has 52 chromosomes. Normally a tetraploid Rhododendron as a parent splits in half contributing 26 chromosomes to the offspring.

A triploid Rhododendron has 39 chromosomes. Half of 39 is between 19 and 20. Darlington showed that if a triploid having 39 chromosmes were to split it would split mainly 19/20 but, also to ever decreasing occurrences, 18/21, 17/22, 16/23, 15/24, 14/25, and 13/26 where the splitting as 13/26 occurs the least. This splitting would form a bell shaped curve between 13 and 26.

Thus, in principle, for Rhododendrons

diploid X diploid usually results in a diploid since 13 + 13 = 26.

tetraploid X tetraploid usually results in a tetraploid since 26 + 26 = 52.

diploid X tetraploid usually results in a triploid since 13 + 26 = 39.

diploid X unreduced diploid can in a few instances result in a triploid since 13 + 26 = 39.

unreduced diploid X tetraploid can in a few instances result in a tetraploid since 26 + 26 = 52.

diploid X super-reduce tetraploid can in a few instances result in a diploid since 13 + 13 = 26

diploid X triploid can in a few instances result in diploid since 13 + 13 = 26 or in a triploid since 13 + 26 = 39.

triploid X tetraploid can in a few instances result in triploid since 13 + 26 = 39 or in a tetraploid since 26 + 26 = 52.

Noteworthy is other researchers found that the offspring of triploids are often aneuploids. For Rhododendrons, an aneuploid would have a number of chromosomes slightly more or less than 26 (2x), 39 (3x), 52 (4x), 65 (5x) or other multiples of 13 (x=13). The unstable meiosis associated with triploids and neotetraploids most likely means that some of the Rhododendrons listed above as diploids, triploids, or tetraploids do not have exactly 26, 39, or 52 chromosomes but instead may have a chromosome count close to these numbers. Flow cytometry being a method of weighting sets of chromosomes rather than counting the number of chromosomes is not well suited to separating euploids from aneuploids when the samples tested involve interactions between a wide range of species within the same genus.

Summary

Named hybrid large leaf elepidote polyploid Rhododendrons have played an important role in the garden for more than 150 years. The physical characteristics associated with polyploid Rhododendrons have proven to be highly desired by gardeners since their introduction by Broughton, Standish and Noble, and Waterer.

The ploidy of more than 100 named hybrid large leaf elepidote Rhododendrons is listed above.

Although to date all species of large leaf elepidote Rhododendrons have tested as diploid species more than 50 named hybrid large leaf elepidote Rhododendrons tested as polyploids.

Approximately 2/3 of the named named hybrid large leaf elepidote Rhododendrons which tested as polyploids tested as triploids with the remaining 1/3 testing as tetraploids.

Triploids can be fertile as both seed and pollen parents. Triploids are able to produce diploid, triploids, tetraploid, and pentaploid offpsring.

Tetraploids are able to produce diploid, triploid, tetraploid, and pentaploid offpsring.

The mechanisms of normal, distributive, unreduced, and super-reduced meiosis are discussed.

This research used as a foundation work done by the following:

Hybridization of Rhododendron Elepidote Polyploids by Jim Barlup

Rules of Engagement: Have Pollen - Will Travel by John and Sally Perkins

Ploidy Levels and Relative Genome Sizes of Diverse Species, Hybrids, and Cultivars of Rhododendron by Jeff R. Jones, Thomas G. Ranney, Nathan P. Lynch, and Stephen L. Krebs

Ploidy Breeding and Interspecific Hybridization in Spathiphyllum and Woody Ornanamentals by Tom Eeckhaut

Meiosis in Polyploids Part I. Triploid and Pentaploid Tulips by W. C. F. Newton and C. D. Darlington

Neopolyploidy in Flowering Plants by Justin Ramsey and Douglas W. Schemske

Posts for each sample ploidy tested are available on the Rosebay Blog. Posts have been grouped using tags to promote easy viewing of related posts. Please weigh in by exploring these posts to discover the wonderful world of ploidy in the Rhododendron garden.

John and Sally Perkins

"(cumberlandense X lutem) not" is a Diploid

2011-10-20T01:39:00.000-07:00

Three seedlings of Rhododendron "(cumberlandense X lutem) not" have been determined to be a diploid 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.

Ploidy testing indicates that Rhododendron luteum may not be the pollen parent of this hybrid.

Summary of Ploidy Levels

Diploid Rhododendron cumberlandense,
Diploid 3 Seedlings of "(cumberlandense X luteum) not",
Tetraploid Rhododendron luteum

Source: Bruce Clyburn

John and Sally Perkins

Reminder: Eastern Regional Conference @ Fri Oct 21 10am - Sun Oct 23, 2011 12pm (ARS Massachusetts Chapter Calendar)

2011-10-19T07:00:00.001-07:00

more details »

Eastern Regional Conference

Hosted by the Middle Atlantic Chapter the Eastern Regional Conference will be held in Richmond, Virginia, October 21 - 23, 2011, at the Doubletree Hotel Richmond Airport.  Highlights include talks by Elizabeth Mundy, owner of Acer Acres Japanese Maples, and Eureka Chapter's Tim Walsh on the Humboldt Botanical Garden.  There will be plant sales, a plant auction and book sales at the event. The ARS Board Meeting will be held on Friday, Octoer 21.  Mark your calendar.

When

Fri Oct 21 10am – Sun Oct 23, 2011 12pm Eastern Time

Where

Doubletree Hotel Richmond Airport, Richmond, Virginia (map)

Calendar

ARS Massachusetts Chapter Calendar

Who

•	John.A.Perkins@gmail.com - creator

Invitation from Google Calendar

You are receiving this email at the account john.a.perkins@gmail.com because you set a reminder for this event on the calendar ARS Massachusetts Chapter Calendar.

You can change your reminders for specific events in the event details page in https://www.google.com/calendar/.

"(flammeum X calendulaceum) not" is a Diploid

2011-10-19T01:34:00.000-07:00

Rhododendron "(flammeum X calendulaceum) not", which is a John Thornton hybrid, has been determined to be a diploid 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.

Ploidy testing indicates that Rhododendron calendulaceum may not be the pollen parent of this hybrid.

Summary of Ploidy Levels

Diploid Rhododendron flammeum,
Diploid "(flammeum X calendulaceum) not",
Tetraploid Rhododendron calendulaceum

Source: John Thronton

John and Sally Perkins

'Consul Pecher' is a Diploid

2011-10-18T01:30:00.000-07:00

Rhododendron 'Consul Pecher', which is a Rhododendron molle hybrid, has been determined to be a diploid 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,
Diploid 'Consul Pecher'

Source: Arnold Arboretum Accession Number: 837-59

John and Sally Perkins

Reminder: Massachusetts Chapter Meeting @ Wed Oct 19 7pm - 9:30pm (ARS Massachusetts Chapter Calendar)

2011-10-17T16:00:00.001-07:00

more details »

Massachusetts Chapter Meeting

Foliage ShowLarry Wallace

When

Wed Oct 19 7pm – 9:30pm Eastern Time

Where

Elm Bank Wellsley, MA (map)

Calendar

ARS Massachusetts Chapter Calendar

Who

•	john.a.perkins@gmail.com - creator

Invitation from Google Calendar

You are receiving this email at the account john.a.perkins@gmail.com because you set a reminder for this event on the calendar ARS Massachusetts Chapter Calendar.

You can change your reminders for specific events in the event details page in https://www.google.com/calendar/.

"Between Two Roads" is a Diploid

2011-10-17T01:27:00.000-07:00

Rhododendron "Between Two Roads" has been determined to be a diploid 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 "Between Two Roads"

Source: Mike Creel

John and Sally Perkins

'Creel's Confetti' is a Diploid

2011-10-16T01:21:00.000-07:00

Rhododendron 'Creel's Confetti' has been determined to be a diploid 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 'Creel's Confetti'

Source: Mike Creel

John and Sally Perkins

'Creel's Alabammy' is a Diploid

2011-10-15T01:19:00.000-07:00

Rhododendron 'Creel's Alabammy', which is a natural hybrid of Rhododendron alabamense, has been determined to be a diploid 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 alabamense,
Diploid 'Creel's Alabammy'

Source: Mike Creel

John and Sally Perkins

Reminder: Eastern Regional Conference @ Fri Oct 21 10am - Sun Oct 23, 2011 12pm (ARS Massachusetts Chapter Calendar)

2011-10-14T07:00:00.001-07:00

more details »

Eastern Regional Conference

Hosted by the Middle Atlantic Chapter the Eastern Regional Conference will be held in Richmond, Virginia, October 21 - 23, 2011, at the Doubletree Hotel Richmond Airport.  Highlights include talks by Elizabeth Mundy, owner of Acer Acres Japanese Maples, and Eureka Chapter's Tim Walsh on the Humboldt Botanical Garden.  There will be plant sales, a plant auction and book sales at the event. The ARS Board Meeting will be held on Friday, Octoer 21.  Mark your calendar.

When

Fri Oct 21 10am – Sun Oct 23, 2011 12pm Eastern Time

Where

Doubletree Hotel Richmond Airport, Richmond, Virginia (map)

Calendar

ARS Massachusetts Chapter Calendar

Who

•	john.a.perkins@gmail.com - creator

Invitation from Google Calendar

You are receiving this email at the account john.a.perkins@gmail.com because you set a reminder for this event on the calendar ARS Massachusetts Chapter Calendar.

You can change your reminders for specific events in the event details page in https://www.google.com/calendar/.

'Creekside' is a Diploid

2011-10-14T01:59:00.000-07:00

Rhododendron 'Creekside', which is a natural hybrid of Rhododendron arborescens, has been determined to be a diploid 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.

Rhododendron 'Creekside' may, also, contain Rhododendron viscosum. Rhododendron 'Creekside' is sometimes called "Running Arborescens".

Summary of Ploidy Levels

Diploid Rhododendron arborescens,
Diploid Rhododendron viscosum,
Diploid 'Creekside'

Source: John and Sally Perkins

John and Sally Perkins

'Pink Puff' is a Diploid

2011-10-13T01:41:00.000-07:00

Rhododendron 'Pink' Puff', which is a natural hybrid of Rhododendron arborescens and Rhododendron cumberlandense, has been determined to be a diploid 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 arborescens,
Diploid Rhododendron cumberlandense,
Diploid Rhododendron arborescens X Rhododendron cumberlandense,
Diploid Rhododendron cumberlandense X Rhododendron rborescens,
Diploid 'Pink Puff'

Source: Connecticut College Arboretum

John and Sally Perkins

cumberlandense X arborescens is a Diploid

2011-10-12T01:39:00.000-07:00

Rhododendron cumberlandense X Rhododendron arborescens has been determined to be a diploid 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 arborescens,
Diploid Rhododendron cumberlandense,
Diploid Rhododendron arborescens X Rhododendron cumberlandense,
Diploid Rhododendron cumberlandense X Rhododendron rborescens,
Diploid 'Pink Puff'

Source: George Hibben

John and Sally Perkins

arborescens X cumberlandense is a Diploid

2011-10-11T01:35:00.000-07:00

Rhododendron arborescens X Rhododendron cumberlandense has been determined to be a diploid 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 arborescens,
Diploid Rhododendron cumberlandense,
Diploid Rhododendron arborescens X Rhododendron cumberlandense,
Diploid Rhododendron cumberlandense X Rhododendron rborescens,
Diploid 'Pink Puff'

Source: George Hibben

John and Sally Perkins

Reminder: Board Meeting @ Wed Oct 12 7:30pm - 9pm (ARS Massachusetts Chapter Calendar)

2011-10-10T16:30:00.001-07:00

more details »

Board Meeting

When

Wed Oct 12 7:30pm – 9pm Eastern Time

Where

Hardings (map)

Calendar

ARS Massachusetts Chapter Calendar

Who

•	John Perkins - creator

Invitation from Google Calendar

You are receiving this email at the account john.a.perkins@gmail.com because you set a reminder for this event on the calendar ARS Massachusetts Chapter Calendar.

You can change your reminders for specific events in the event details page in https://www.google.com/calendar/.

'Toy' is a Diploid

2011-10-10T01:55:00.000-07:00

Rhododendron 'Toy', which is a Polly Hill selection, has been determined to be a diploid 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 'Toy'

Source: George Hibben

John and Sally Perkins

'Casille' is a Diploid

2011-10-09T01:06:00.000-07:00

Rhododendron 'Casille' has been determined to be a diploid 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.

The Pastel series which includes 'Casille' is documented to contain Rhododendron alabamense, Rhododendron canescens, and Rhododendron flammeum.

Summary of Ploidy Levels

Diploid Rhododendron alabamense,
Diploid Rhododendron canescens,
Diploid Rhododendron flammeum,
Diploid 'Casille',
Diploid "Pastel #6",
Diploid "Pastel #7",
Diploid "Pastel #20"

Source: Woodlanders Nursery

John and Sally Perkins

"(viscosum X arborescens) not" is a Tetraploid

2011-10-08T01:39:00.000-07:00

Two plants labeled Rhododendron viscosum X Rhododendron arborescens have 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.

The ploidy test indicates this plant may instead contain Rhododendron atlanticum. Both of thedse plants were raised by George Hibben.

Summary of Ploidy Levels

Diploid Rhododendron viscosum,
Diploid Rhododendron arborescens,
Tetraploid Rhododendron atlanticum,
Tetraploid "(Rhododendron viscosum X Rhododendron arborescens) not"

Source: Arnold Arboretum Accession Number: 139-98-A
Source: George Hibben

John and Sally Perkins

Rhododendron "alabamense not" is a Tetraploid

2011-10-07T01:56:00.000-07:00

A plant labeled Rhododendron alabamense 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.

The ploidy test indicates this plant may instead be Rhododendron colemanii.

Summary of Ploidy Levels

Diploid Rhododendron alabamense,
Tetraploid Rhododendron colemanii,
Tetraploid Rhododendron "alabamense not"

Source: Rarefind Nursery

John and Sally Perkins

"Speciosum Yellow #3" is a Tetraploid

2011-10-06T01:51:00.000-07:00

Rhododendron "Speciosum Yellow #3" 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.

Clearly Rhododendron "Speciosum Yellow #3" is not straight Rhododendron flammeun.

Summary of Ploidy Levels

Diploid Rhododendron flammeun,
Tetraploid "Speciosum Yellow #3"

Source: Rarefind Nursery

John and Sally Perkins

October Newsletter

2011-10-05T20:35:00.000-07:00

Reminder: Board Meeting @ Wed Oct 12 7:30pm - 9pm (ARS Massachusetts Chapter Calendar)

2011-10-05T16:30:00.001-07:00

more details »

Board Meeting

When

Wed Oct 12 7:30pm – 9pm Eastern Time

Where

Hardings (map)

Calendar

ARS Massachusetts Chapter Calendar

Who

•	john.a.perkins@gmail.com - creator

Invitation from Google Calendar

You are receiving this email at the account john.a.perkins@gmail.com because you set a reminder for this event on the calendar ARS Massachusetts Chapter Calendar.

You can change your reminders for specific events in the event details page in https://www.google.com/calendar/.

atlanticum X (atlanticum X molle) is a Tetraploid

2011-10-05T01:53:00.000-07:00

Four seedlings of Rhododendron atlanticum X (Rhododendron atlanticum X Rhododendron molle) have 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.

These seedlings do show the influence of Rhododendron molle or maybe Rhododendron luteum. Successful 4X X 2X crosses in deciduous azaleas are rare.

Summary of Ploidy Levels

Diploid Rhododendron molle,
Tetraploid Rhododendron atlanticum,
Tetraploid Rhododendron luteum,
Tetraploid 4 Seedlings of Rhododendron atlanticum X (Rhododendron atlanticum X Rhododendron molle)

Source: Bruce Clyburn

John and Sally Perkins

'Fireflash' X 'Buttercup' is a Tetraploid

2011-10-04T01:48:00.000-07:00

Rhododendron 'Fireflash' X 'Buttercup' 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

Tetraploid 'Fireflash' X 'Buttercup'

Source: Joe Bruso

John and Sally Perkins

"Choptank" is a Tetraploid

2011-10-03T01:27:00.000-07:00

Rhododendron "Choptank" from Longwood Gardens 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.

Ploidy testing indicates that the Choptank azaleas are tetraploids. Choptanks are most likely derived from only tetraploid species. Rhodendron atlanticum is the primary species in the background of most Choptank azaleas. Yellow Choptanks may contain Rhodendron austrinum.

Summary of Ploidy Levels

Tetraploid Rhodendron atlanticum,
Tetraploid Rhodendron austrinum,
Tetraploid "Choptank"

Source: Longwood Gardens Accession Number: 1994-0808-C

John and Sally Perkins

'Smoky Mountaineer' OP is a Tetraploid

2011-10-02T01:23:00.000-07:00

Rhododendron 'Smoky Mountaineer' OP 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

Tetraploid 'Smoky Mountaineer',
Tetraploid 'Smoky Mountaineer' OP

Source: George Hibben

John and Sally Perkins

'Lady Roseberry' OP is a Tetraploid

2011-10-01T01:22:00.000-07:00

Rhododendron 'Lady Roseberry' OP 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

Tetraploid 'Lady Roseberry',
Tetraploid 'Lady Roseberry' OP

Source: George Hibben

John and Sally Perkins

'Princesse d' Orange' is a Tetraploid

2011-09-30T01:40:00.000-07:00

Rhododendron 'Princesse d' Orange', which is a Ghent 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

Diploid 'Miniatum Floribundum',
Triploid 'Aida',
Triploid 'Bronze Unique',
Triploid 'Croceum Tricolor',
Triploid 'Daviesii',
Triploid 'Deep Rose',
Triploid 'Freya',
Triploid 'Gloria Mundi',
Triploid 'Il Tasso',
Triploid 'Josephine Klinger',
Triploid 'Phebe',
Triploid 'Phidias',
Triploid 'Pontica Album',
Triploid 'Van Houttei Flore Pleno',
Triploid 'Velasquez',
Triploid/Tetraploid 'Praxitèle',
Tetraploid 'Admiraal De Ruyter',
Tetraploid 'Altaclerensis',
Tetraploid 'Ariel',
Tetraploid 'Beaté Céleste',
Tetraploid 'Bijou des Amateurs',
Tetraploid 'Bouquet de Flore',
Tetraploid 'Cardinal,
Tetraploid 'Comte de Flandre',
Tetraploid 'Corneille',
Tetraploid 'Directeur Charles Baumann',
Tetraploid 'Durante Alle',
Tetraploid 'Electum',
Tetraploid 'Eugénie',
Tetraploid 'Fénelon',
Tetraploid 'Flameola Incarnata',
Tetraploid 'Héroine Plena,
Tetraploid 'Heureuse Surprise',
Tetraploid 'Hollandia',
Tetraploid 'Hora',
Tetraploid 'Ignacea',
Tetraploid 'Igneum Novum',
Tetraploid 'Il Tasso',
Tetraploid 'Jenny Lind',
Tetraploid 'Juliana Nova',
Tetraploid 'Julius Caesar',
Tetraploid 'Leibuir',
Tetraploid 'Lelia',
Tetraploid 'Madame Gustave Guillemot',
Tetraploid 'Marie Verschaffelt',
Tetraploid 'Minerva',
Tetraploid 'Nancy Waterer',
Tetraploid 'Oscar I',
Tetraploid 'Perfecta',
Tetraploid 'Princesse d' Orange',
Tetraploid 'Raphael de Smet'

Source: Azaleatuin

John and Sally Perkins

atlanticum X caledulaceum is a Tetraploid

2011-09-29T01:19:00.000-07:00

[Rhododendron atlanticum X Rhododendron calendulaceum] "Broken Arrow", which is a Dick Jaynes hybrid, 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

Tetraploid Rhododendron atlanticum,
Tetraploid Rhododendron calendulaceum,
Tetraploid Rhododendron atlanticum X Rhododendron calendulaceum "Broken Arrow",
Tetraploid Rhododendron atlanticum X Rhododendron calendulaceum orange,
Tetraploid Rhododendron atlanticum X Rhododendron calendulaceum pink

Source: Arnold Arboretum Accession Number: 410-2002

John and Sally Perkins

'Wingard's Gold' is a Tetraploid

2011-09-28T01:17:00.000-07:00

Rhododendron 'Wingard's Gold' 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

Tetraploid 'Wingard's Gold'

Source: Mike Creel

John and Sally Perkins

Rhododendron luteum is a Tetraploid

2011-09-27T01:05:00.000-07:00

Rhododendron luteum 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 luteum was also determined to be a tetraploid using flow cytometry by Dr. Thomas Ranney, J.R. Jones, and Nathan Lynch.

Summary of Ploidy Levels

Tetraploid Rhododendron luteum,
Tetraploid Rhododendron luteum 'Golden Comet',
Tetraploid Rhododendron luteum Orange form,
Tetraploid Rhododendron luteum Yellow form

Source: Arnold Arboretum
Source: John and Sally Perkins
Source: Kristian Theqvist

John and Sally Perkins

"Orange Ruffle" is a Tetraploid

2011-09-26T01:52:00.000-07:00

Rhododendron "Orange Ruffle", which is a Frank Abbott hybrid, has been determined to be a tretraploid 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 Rhododendron ""Orange Ruffle"

Source: John Abbott

John and Sally Perkins

Weston Nurseries Plants Still Available

2011-09-25T05:19:00.001-07:00

We still have some of the Weston Nurseries hybrids available for sale.

In keeping with our Donated Plant sale tradition whereby at the end of the sale we cut all prices in half, prices on these plants will remain at half price, as follows.

Prices

$10 per 6-pack.

$22 per Flat (three 6-packs)

All proceeds go to the Mass Chapter. These are all excellent plants, and do not look like "left overs".

If you need to create a hedge, or want to procure plants for growing on as gifts, this is a low-cost way to do so.

The plants are at my home in Hopkinton, MA. Contact me to arrange a time to stop by to make a purchase.

Selections

Cultivar	Rhodo/Azalea Type	Description	Zone
smirnowii x yak	Broad leaved evergreen Rhodo	Pink, fading to lighter pink or white. Deep green leaves with heavy indumentum.	5
Blue Baron	Small leaved evergreen Rhodo (lep)	Bluest of blue flowers.	6
Milestone	Small leaved evergreen Rhodo (lep)	Dark Pink (red if you use your imagination). Blooms in April.	5
Abigail Adams	Evergreen Azalea	Large pink blooms. Wider than tall. Does well in heavy shade or sun	5
Millennium	Deciduous Azalea	Fragrant, red, in mid-July. Leaves with silver/green undersides.	4
Nectar	Deciduous Azalea	Fragrant, pink-orange, in late June	5

Joe Bruso

61 South Mill St.

Hopkinton, MA

jpbruso@aol.com

508.435.8217

"Graftonense" is a Tetraploid

2011-09-25T01:38:00.000-07:00

Rhododendron "Graftonense", which is a Frank Abbott hybrid, has been determined to be a tretraploid 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 Rhododendron "Graftonense"

Source: John Abbott

John and Sally Perkins

"Gladywense" is a Triploid

2011-09-24T01:46:00.000-07:00

Rhododendron "Gladywense" has been determined to be a triploid 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

Triploid Rhododendron "Gladywense"

Source: Arnold Arboretum Accession Number: 979-67-A

John and Sally Perkins

Rhododendron "calendulaceum not" is a Triploid

2011-09-23T01:39:00.000-07:00

Rhododendron "calendulaceum not", which appears to be a hybrid between Rhododendron flammeum and Rhododendron calendualceum, has been determined to be a triploid 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

Diploid Rhododendron flammeum,
Triploid Rhododendron "calendulaceum not",
Tetraploid Rhododendron calendualceum

Source: Arnold Arboretum Accession Number: 109-2007-Y

John and Sally Perkins

'Unique' is a Triploid?

2011-09-22T01:23:00.000-07:00

Rhododendron 'Unique', which is a Ghent hybrid, has been determined to be a triploid 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 'Unique' was determined to be a tetraploid using flow cytometry by Tom Eeckhaut.

Summary of Ploidy Levels

Triploid 'Unique'

Source: Arnold Arboretum Accession Number: 72-57-B

John and Sally Perkins

Clones may not be Identical

2011-09-21T09:07:00.000-07:00

"Using DNA sequencing techniques that can decode the complete genome of an organism in one go (so-called ‘whole genome sequencing’) the researchers analyzed ‘clones’ of the small flowering plant ‘thalecress’ (Arabidopsis). They found that observable variations in regenerant plants are substantially due to high frequencies of mutations in the DNA sequence of these regenerants, mutations which are not contained in the genome of the parent plant."

Why plant 'clones' aren't identical

Rhododendron occidentale hybrid is a Triploid

2011-09-21T01:17:00.000-07:00

A Rhododendron occidentale hybrid has been determined to be a triploid 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

Diploid Rhododendron occidentale,
Triploid Rhododendron occidentale hybrid

Source: George Hibben

John and Sally Perkins

Audra State Park contains Triploids

2011-09-20T01:48:00.000-07:00

Two deciduous azalea hybrids in Audra State Park, West Virginia have been determined to be triploids 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.

Audra State Park in West Virginia contains Rhododendron arborescens, Rhododendron maximum, Rhododendron periclymenoides, maybe
Rhododendron prinophyllum, and Rhododendron calendulaceum.

Summary of Ploidy Levels

Diploid Rhododendron arborescens,
Diploid Rhododendron maximum,
Diploid Rhododendron periclymenoides,
Diploid Rhododendron prinophyllum,
Triploid 2 deciduous azalea hybrids in Audra State Park,
Tetraploid Rhododendron calendulaceum

Source: Audra State Park, West Virginia

John and Sally Perkins

Reminder: Massachusetts Chapter Meeting @ Wed Sep 21 6:30pm - 9pm (ARS Massachusetts Chapter Calendar)

2011-09-19T15:30:00.001-07:00

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Massachusetts Chapter Meeting

Meeting / Pot LuckDonate Plant Sale / Weston Nursery Plants / Deciduous Azalea Seedlings

When

Wed Sep 21 6:30pm – 9pm Eastern Time

Where

Elm Bank Wellsley, MA (map)

Calendar

ARS Massachusetts Chapter Calendar

Who

•	john.a.perkins@gmail.com - creator

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You are receiving this email at the account john.a.perkins@gmail.com because you set a reminder for this event on the calendar ARS Massachusetts Chapter Calendar.

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"Pastel #20" is a Diploid

2011-09-19T01:50:00.000-07:00

"Pastel #20" has been determined to be a diploid 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.

The Pastel series is documented to contain Rhododendron alabamense,
Rhododendron canescens, and Rhododendron flammeum.

Summary of Ploidy Levels

Diploid Rhododendron alabamense,
Diploid Rhododendron canescens,
Diploid Rhododendron flammeum,
Diploid 'Casille',
Diploid "Pastel #6",
Diploid "Pastel #7",
Diploid "Pastel #20"

Source: Woodlanders Nursery

John and Sally Perkins

Donated Plant Sale - Seedlings

2011-09-18T05:07:00.000-07:00

In additional to the Weston plants, 6 inch tall deciduous azalea seedlings from a cross of a "White Calendulaceum" Skinner 166 by calenducaleum 'Smokey Mountaineer' will be sold at our annual Donated Plant Sale, occurring at our next Chapter meeting, Wednesday, September 21 at the Elm Bank East Wing.

The cost of these deciduous azalea seedlings will be 1 for $5 or 3 for $10. These seedlings could range in color from white to pink to yellow to orange to red.

"Pastel #7" is a Diploid

2011-09-18T01:49:00.000-07:00

"Pastel #7" has been determined to be a diploid 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.

The Pastel series is documented to contain Rhododendron alabamense,
Rhododendron canescens, and Rhododendron flammeum.

Summary of Ploidy Levels

Diploid Rhododendron alabamense,
Diploid Rhododendron canescens,
Diploid Rhododendron flammeum,
Diploid 'Casille',
Diploid "Pastel #6",
Diploid "Pastel #7",
Diploid "Pastel #20"

Source: Woodlanders Nursery

John and Sally Perkins

"Pastel #6" is a Diploid

2011-09-17T01:47:00.000-07:00

"Pastel #6" has been determined to be a diploid 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.

The Pastel series is documented to contain Rhododendron alabamense,
Rhododendron canescens, and Rhododendron flammeum.

Summary of Ploidy Levels

Diploid Rhododendron alabamense,
Diploid Rhododendron canescens,
Diploid Rhododendron flammeum,
Diploid 'Casille',
Diploid "Pastel #6",
Diploid "Pastel #7",
Diploid "Pastel #20"

Source: Woodlanders Nursery

John and Sally PerkinsDiploid 'Casille',

'Phyllis Korn' x 'Trude Webster' is a Pentaploid

2011-09-16T01:52:00.000-07:00

Two seedlings of Rhododendron 'Phyllis Korn' x 'Trude Webster', which is a Jim Barlup hybrid, have been determined to be a pentaploid 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.

In the case of the pentaploid seedlings of 'Phyllis Korn' (3X) x 'Trude Webster' (4X), a triploid by a tetraploid produced a pentaploid indicating that the triploid seed parent 'Phyllis Korn' was most likely unreduced. In other words, the pentaploid seedlings of 'Phyllis Korn' x 'Trude Webster' having 65 chromosomes most likely received 39 chromosomes from the triploid 'Phyllis Korn' and 26 chromosomes from the tetraploid 'Trude Webster'. Considering the parents are a triploid and a neotetraploid, meiosis may not be normal for either parent.

Summary of Ploidy Levels

Triploid 'Phyllis Korn'
Tetraploid 'Trude Webster',
Pentaploid 2 Seedlings of 'Phyllis Korn' x 'Trude Webster'

Source: Jim Barlap

John and Sally Perkins

Special Sale of Weston Nurseries Plants

2011-09-15T05:40:00.000-07:00

To Mass Chapter Members,

As occurred 2 years ago, we again have the opportunity to purchase very hardy Weston Nurseries-developed rhododendrons and azaleas at irresistible prices. Wayne Mezitt, owner of Weston Nurseries, has provided the Chapter with small plants in order to get them into the hands of people who can appreciate them. Since Weston Nurseries has stopped doing their own propagation, these are likely to be the last small plants we will obtain from them. This is an opportunity to obtain some of Weston's best introductions at great prices. These plants were bred for the New England climate and should perform exceptionally well for you.

Supplies for some selections should be sufficient, but others are limited. Most are in 3" cells, with a few in 2" cells. In many cases there are two plants to the cell, which can be separated. Many of the deciduous azaleas have bloom buds.

The plants will be sold at our annual Donated Plant Sale, occurring at our next Chapter meeting, Wednesday, September 21 at the Elm Bank East Wing. See the latest Chapter Newsletter for directions and details on the events scheduled for this meeting. Due to the volume of plants available, sales will begin about 6:30 PM, prior to the start of the Pot Luck Supper. Please arrive early for the best selection.

Prices

$20 per 6-pack.

$45 for three 6-packs (1 flat in most cases). Each 6-pack contains 6 to 10 plants.

Exceptions:

· Smirnowii-Yak hybrid, in individual 3" pots, are $3 each.

· Selections in short supply (as noted below) will be sold as 3 packs at $9 each to allow more people to obtain them.

Selections

Cultivar	Rhodo/Azalea Type	Description	Limited Supply?
smirnowii x yak	Broad leaved evergreen Rhodo	Pink, fading to lighter pink or white. Deep green leaves with heavy indumentum.
Blue Baron	Small leaved evergreen Rhodo (lep)	Bluest of blue flowers.	Y
Milestone	Small leaved evergreen Rhodo (lep)	Dark Pink (red if you use your imagination). Blooms in April.	Y
Abigail Adams	Evergreen Azalea	Large pink blooms. Wider than tall. Does well in heavy shade or sun
R. kiusianum	Evergreen Azalea	Tiny leaves. One of best evergreen azalea species for New England.	Y
Anna's Smile	Deciduous Azalea	Fragrant, pink with golden eye turning peachy pink, in early June.	Y
Golden Showers	Deciduous Azalea	Fragrant, peach/orange, in mid-July.	Y
Millennium	Deciduous Azalea	Fragrant, red, in mid-July. Leaves with silver/green undersides.
Nectar	Deciduous Azalea	Fragrant, pink-orange, in late June

A few words on some selections:

I consider Abigail Adams the best hybrid evergreen azalea for my Zone 5b garden. Unlike many evergreen azalea hybrids, it is fully hardy for me, never showing any winter damage. The very large blooms are a wonderful shade of medium pink, totally covering the plant with, even in a shady location. When grown in adequate sun, the foliage turns orange/red in the fall.

Anyone who has seen Blue Barron in bloom in our display garden knows what a special plant it is. It is one of, if not the bluest, most floriferous of the blue small leaved rhododendrons that can be grown in our area. Blue Barron won Best in Show in this year's Truss Show. Need I say more? We have a limited supply of this cultivar. First come, first served.

Joe Bruso

Rhododendron diaprepes X sutchuenense is a Diploid

2011-09-15T01:36:00.000-07:00

Rhododendron diaprepes X Rhododendron sutchuenense has been determined to be a diploid 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 diaprepes 'Gargantua', which is a tetraploid, may have been one of the parents in the cross of Rhododendron diaprepes X Rhododendron sutchuenense. Neotetraploids can produce diploid offspring.

Rhododendron diaprepes is most likely a diploid species.

Summary of Ploidy Levels

Diploid Rhododendron diaprepes X Rhododendron sutchuenense,
Tetraploid Rhododendron diaprepes 'Gargantua'

Source: Al Fitzburg

John and Sally Perkins