|Cheon, Eun Ju|
|Lee, Ae Kyung|
|Suh, Jeung Keun|
|Joung, Young Hee|
|Choi, Ik Young|
|Lee, Nam Sook|
|Park, Jae Ok|
|Yeau, Sung Hee|
Submitted to: Acta Horticulture Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 8/28/2008
Publication Date: 1/3/2009
Citation: Roh, M.S., Lee, A.K., Suh, J.K., Joung, Y.H., Choi, I.Y., Lee, N.S., Park, J.O., Koshioka, M., Yeau, S.H., Slovin, J.E. 2009. Evaluation, characterization, and identification of woody landscape plants. Acta Hort. 769:327-338.
Interpretive Summary: The nursery industry has generally relied on a very limited number of species and selections of trees and shrubs in the landscape and woody landscape plants are not typical agronomic crops. The management of woody landscape plant germplasm is very complex and requires a multi-disciplinary approach. It is important to collect, maintain, evaluate, document, and distribute newly acquired germplasm to meet the challenges of changing environments, pests, and diseases as well as increasing genetic diversity and consumer choices. It is important to investigate seed germination, vegetative propagation, overwinter loss, and growth and flowering, in order to fully evaluate existing collections that have not been adequately evaluated as landscape plants. It is important to keep and administer accurate plant records in collaboration with public and/or private sector organizations and to make the records and germplasm available to the user groups. Germplasm must be characterized using molecular markers to enable us to verify that collections represent adequate genetic variability. The overall objectives of the Woody Landscape Plant Germplasm Repository (WLPGR) are to collect and conserve genetic resources, to distribute germplasm, to evaluate the preceding genetic resources for horticultural merit, and to characterize them genetically, and to transfer technology in the form of the preceding genetic resources and associated information to researchers and breeders’ world wide by electronic linkage among US National Arboretum, National Plant Germplasm System and the public sector. In this review article, brief descriptions of the WLPGR program and several of the recent achievements are summarized.
Technical Abstract: The objectives of the Woody Landscape Plants Germplasm Repository (WLPGR) program at the US National Arboretum (USNA) are composed of two parts: repository activities and a research component. Repository activities are to introduce, maintain, and distribute diverse and wild-origin genetic resources of trees and shrubs for landscape use. Research components include evaluation, characterization and identification of germplasm. Seed germination and over-wintering survival problems in Styrax japonicus have been studied. Seeds require one month of warm stratification followed by two to three months of cold stratification to achieve greater than 85% germination within one month of sowing. The viability of Ardisia crenata seeds, which are recalcitrant and viable for about 2 to 4 weeks, can be extended to 15 weeks. Identification of Acer griseum germplasm and of an interspecific hybrid was investigated using RAPD. Characterization of Pinus sylvestris var. sylvestriformis by cpDNA and SSR revealed that the hybrid formula, P. densiflora ' P. sylvestris may be appropriate, rather than P. sylvestris var. sylvestriformis. Molecular markers including RAPD, ISSR, and SNP have also been utilized to study Ilex × wandoensis, Prunus including P. yedoensis from wild populations and cultivated sources, and Corylopsis including C. coreana, C. glabrescens, and C. gotoana. A SCAR marker differentiated a subgroup of seedlings from a natural cross of a white berry form of A. crenata with variegated foliage form of A. crenata with red berries. For Camellia, SCAR markers for cold hardiness are being developed to screen progeny of crosses between cold hardy and non-cold hardy lines.