Rock Garden Quarterly Summer 2012 - (Page 229)

Taxonomy and Nomenclature: Section Nosphinium, subsect. Pedatae [proposed new classification (Marcussen, 2010)]. Viola pedata L. Sp. Pl. 933. 1753. There are strong morphological similarities with V. beckwithii that also has bicolored flowers, large open flat flowers, no cleistogenes, similar fibrous leaf texture, narrow leaf lobes, glands on the tips of the leaf segment, the same pattern of pubescence and similar rhizome and root systems. Polyploidy plays a crucial role in creating diversity in plants. The base number of chromosomes in a species is represented by ‘x’. V. pedata is a decaploid species (2N=10x=54), the result of ancient hybridization events between three diverse North American lineages 12-14 million years ago. The three ancestors were from the diploid yellow-flowered section Chamaemelanium series Nudicaules (2n=2x=12), the tetraploid white-flowered section Plagiostigma (2n=4x=24) and the tetraploid purple-flowered section Viola (2n=4x=20). Although this 10-ploid species should have 2n=56 (12+24+20), one chromosome pair has been dropped, leaving the 10-ploid level of 2n=54 (Marcussen, 2011). 00190002.TIF 00190005.TIF 00190007.TIF 00190009.TIF 00190010.TIF 00190011.TIF 00190013.TIF 00190014.TIF 00190012.TIF Viola pedata 229

Table of Contents for the Digital Edition of Rock Garden Quarterly Summer 2012

Digital Quarterly
Expanding Panayoti's Axioms
Photo Contest 2012
Photographing Alpine Plants: A Landscape Point of View
NARGS 2013 Election Timetable
Rock Gardening from Scratch - Seeds
Kim Blaxland and the Violets of North America
Viola pedata
Violas, Kim, and Us - A Celebration
Cooking Native Japanese Plants
Carl Gehenio Memorial Trough Show
Fire in the Hole: Phlox across Colorado
Rebuilding a Rock Garden in Pittsburgh
A Remarkable Garden: David Douglas and the Shrub-steppe of the Columbia Plateau
Bookshelf - Reviews
Swedish Dreams
Treasurer's Report
Bulletin Board
2012 - Eastern Study Weekend: October, Pittsburgh

Rock Garden Quarterly Summer 2012