Location: Floral and Nursery Plants Research Unit
Project Number: 1230-21000-061-00
Start Date: Apr 14, 2013
End Date: Apr 13, 2018
The approach to achieving the objectives of this Project will build upon previous work, but will also establish populations, knowledge, and germplasm that will be used for the next 10-20 years. Over the next five years, the long-term objective will be accomplished through the following general approach. Parental germplasm will be collected from native habitats, botanical repositories, and commercial sources, and will be evaluated for traits of interest. Controlled intra- and interspecific hybridizations will be carried out in the field or greenhouse to produce hybrid progeny, to determine compatibility among parents, and to study breeding systems and inheritance of traits of interest. As needed, molecular markers will be used in conjunction with classical taxonomy to determine genetic relationships among taxa and verify parentage of hybrids. Resultant progeny will be evaluated, and promising selections will be transplanted to the field. Selections developed during previous project cycles that have performed well will be propagated. These include elite clones of Catalpa, Deutzia, Ilex, Lagerstroemia, Magnolia, Platanus, Prunus, Syringa, and Tsuga, among others. These plants will be evaluated in replicated field trials and released if warranted. To initiate a new boxwood breeding program, germplasm will be collected through existing national and international collaborators. Accessions will be screened for ploidy, resistance to boxwood blight, and horticultural traits, and selected taxa will be used in hybridizations to create novel genotypes that combine disease resistance with quality ornamental and production traits. Accessions that will be used for ploidy manipulation will be screened to determine genome sizes and relative ploidy levels using flow cytometry. Chromosomes of select taxa will be doubled as needed, and plants will then be used to conduct appropriate inter-ploid crosses for taxa-specific breeding goals. Treated material will be tested for ploidy and then stabilized and propagated.