CRIS Project Title:  
Taxonomy And Genetic Diversity Assessment Of Landscape Trees And Shrubs

INTRODUCTION:  
The primary goals for this project are to assess systematic relationships and the amount and apportionment of genetic diversity within and between species.  The work focuses on the North American taxa of Celtis and Quercus, developing genetic marker systems that will facilitate this work and at the same time be useful for breeding and selection work in these genera.  The project also manages and develops the National Arboretum herbarium, the only large herbarium in USDA, focused on cultivated/domesticated plants; collaborates in the documentation of emerging invasive woody plants, and the investigation of traits contributing to their invasiveness; and works to determine the valid botanical and cultivar names for landscape trees and shrubs, and to ensure that those names are properly and consistently applied.

PROGRESS:  
Demonstrated that hybrids between species of Celtis are much rarer in nature, and harder to synthesize, than previously reported.  Demonstrated that many natural populations of Celtis show developmental failure resulting in the production of little or no viable pollen, suggesting that apomixis should be tested for in the genus.  Added several thousand specimens a year to the herbarium, including collections documenting important breeding and cultivar collections from many parts of the country.  Developed a website for the herbarium, making information on the collection and images of important specimens (including all botanical type specimens and many horticultural standards) widely available.  Carried out other research projects of limited scope relating to other families and genera, including contributions nec essary to ensure stable, accurate nomenclature for cultivated plants and their wild relatives and contributions to collaborative projects to produce taxonomic manuals for China and various areas of North America.

PLANS:   
To investigate cytogenetics of Celtis, investigate the reporductive biology of non-pollen-producing populations, and complete studies of relationships among the species using morphological and DNA markers.  Complete investigations on distribution of genetic markers in selected oaks.  Continue herbarium documention of important breeding and cultivar collections.  Make the general specimen database for the herbarium available on the Web.  Continue to participate in important collaborative taxonomic projects.

RECENT PUBLICATIONS:

2000.  A. T. Whittemore.  Musaceae.  Flora of North America  22: 305-309.

2000.  A. T. Whittemore.  Zingiberaceae.  Flora of North America  22: 302-304.

2000.  L. J. Dorr & A. T. Whittemore.  Obituary of:  Ada Nesta Dunn Ewan (1908 - 2000).  Taxon  49: 817-818.

2000.  W. J. Kress and A. T. Whittemore.  Heliconiaceae.  Flora of North America  22: 299-301.

2001.  L. R. Stark and A. T. Whittemore.  Bryophytes from the northern Mojave Desert.  Southwestern Naturalist  45: 226-241.

2001.  H. Bischler and A. T. Whittemore.  Cronisia and its two species, C. fimbriata  and C. weddellii.  Cryptogamie: Bryologique et Lichénologique 22: 167-174.

2002.  A. T. Whittemore.  Obituary of:  Joseph Andorfer Ewan (1909 - 1999) and Ada Nesta Ewan (1908 - 2000).  Bartonia 61: 137-142.

2002.  L. R. Stark, A. T. Whittemore and B. D. Mishler.  Noteworthy bryophyte records from the Mojave Desert.  Madroño 49: 49-53.

2003.  A. T. Whittemore.  Noteworthy collections (District of Columbia).  Castanea 68: 261.

2003.  A. T. Whittemore.  Interspecific hybridization in Texas Celtis.  Abstract.  Botany 2003, Mobile AL.

2003.  A. T. Whittemore and A. E. Schuyler.  Scirpus.  Flora of North America  23: 8-21.

2003.  A. A. Reznicek., J. E. Fairey III and A. T. Whittemore.  Scleria.  Flora of North America  23: 242-251.

2004.  Fu Liguo, Xin Yiqun, and A. T. Whittemore.  Ulmaceae.  Flora of China, volume 5: 1-19.

2004  A. T. Whittemore.  Sawtooth oak (Quercus acutissima, Fagaceae) in North America.  Sida 21: 447-454.

2005.  A. T. Whittemore.  Sexual sterility and apomixis in eastern North American Celtis.  Abstract.  Botany 2005, Austin, TX.

2005.  A. T. Whittemore.  Introgression, genetic structure, and taxonomic status in the Celtis laevigata - C. reticulata complex (Cannabaceae).  Systematic Botany 30: 809-817.

2005.  A. T. Whittemore.  Validation of the Name Ilex Xaquipernyi J. B. Gable (Aquifoliaceae).  Novon 15: 493-494.

2005  A. T. Whittemore and K. C. Nixon.  Proposal to reject the name Quercus prinus L. (Fagaceae).  Taxon 54: 213-214.

2006.  A. T. Whittemore.  The flora of the United States and policy for the control of alien plants.  Symposium on the distribution and management of alien species in Jeju Island, Korea.  Abstract.  Korea Forest Research Institute, Jeju.

2006.  A. T. Whittemore.  ITS evolution in Celtis (Cannabaceae).  Abstract.  Botany 2006, Chico CA.

2006.  A. T. Whittemore.  Notes on Southwestern Moraceae.  Sida: Contributions to Botany 22(1): in press.

In press.  A. T. Whittemore.  Zingiberaceae.  The Jepson Manual: Higher Plants of California ed. 2.

In press.  A. T. Whittemore.  Juglandaceae.  The Jepson Manual: Higher Plants of California ed. 2.

In press.  A. T. Whittemore.  Caprifoliaceae.  Flora of Missouri, volume 3.

In press.  A. T. Whittemore.  Juglandaceae.  Flora of Missouri, volume 3.

In press.  A. T. Whittemore.  Moraceae.  Flora of Missouri, volume 3.

In press.  A. T. Whittemore.  Platanaceae.  Flora of Missouri, volume 3.

In press.  A. T. Whittemore.  Hamamelidaceae.  Flora of Missouri, volume 3.

In press.  A. T. Whittemore.  Leitneriaceae.  Flora of Missouri, volume 3.

In press.  A. T. Whittemore.  Menispermaceae.  Flora of Missouri, volume 3.

In press.  A. T. Whittemore.  Ranunculaceae.  Flora of Missouri, volume 3.

In press.  A. T. Whittemore.  Betulaceae.  Flora of Missouri, volume 2.

In press.  A. T. Whittemore.  Fagaceae.  Flora of Missouri, volume 2.

In press.  A. T. Whittemore.  Berberidaceae.  Flora of Missouri, volume 2.

In press.  A. T. Whittemore and E. McClintock.  Pittosporaceae.  Flora of North America vol. 8.

Accepted pending revision.  A. T. Whittemore and A. H. Townsend.  Hybridization and Self-Compatibility in Celtis: AFLP Analysis of Controlled Crosses.  Journal of the American Society of Horticultural Science.

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Last Updated   December 22, 2006 8:32 AM
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