William C. (Bill) Johnson Address: Dept. of Horticultural Sciences Cornell University, Geneva NY email address: wcj4@cornell.edu (315) 787-2480 (Office) (315) 787-2216 (Fax) USDA-ARS /Cornell University Apple Rootstock Breeding/Evaluation Program

Education:

B.S. Plant Breeding, UC Davis, 1991
Ph.D., Genetics, UC Davis, 1997

Current Research Interests:

Evaluating apple rootstock genotypes for disease resistance, tree size control, productivity, and precocity. Breeding new varieties of apple rootstocks. Sexual compatibility, graft compatibility, and speciation among members of Malus spp. Relationships between root morphology, scion growth, and orchard performance traits. Mechanisms for rootstock control of tree size, precocity, and productivity. Utilization of genetic resources in applied breeding programs. Application of molecular marker technology to breeding programs for perennial tree species.

Research Experience:

Post Doctoral Researcher, UC Davis, 1997-1998.

Apple rootstock breeding and evaluation program research geneticist (USDA/ARS) / Adjunct Assistant Professor (Cornell University), 1998 - present.

Publications List

Debouck, Daniel G., Orlando Toro, Oscar M. Paredes, William C. Johnson, and Paul Gepts. 1993. Genetic diversity and ecological distribution of Phaseolus vulgaris (Fabaceae) in Northwestern South America. Economic Botany 47(4). p. 408-423.

Guzmán, Pablo, Robert L. Gilbertson, Rubens O. Nodari, William C. Johnson, Steve R. Temple, Dexter Mandala, Alex B.C. Mkandawire, and Paul Gepts. 1995. Characterization of variability in the fungus Phaeoisariopsis griseola suggests coevolution with the common bean Phaseolus vulgaris. Phytopathology 85:600-607.

Johnson, William C., Cristina Menendez, Rubens O. Nodari, Epimaki M. K. Koinange, and Paul Gepts, 1996. Association of a seed weight factor with the phaseolin seed storage protein across genotypes, environments, and genomes in Phaseolus-Vigna spp.: Sax (1923) revisited. Journal of Quantitative Trait Analysis 2 (5) (http://probe.nalusda.gov:8000/otherdocs/ jqtl/jqtl1996-05/sax2htm)

Johnson, William C., Pablo Guzmán, Dexter Mandala, Alex B.C. Mkandawire, Steve R. Temple, Robert L. Gilbertson, and Paul Gepts, 1997. Molecular tagging of the bc-3 gene for introgression into Andean common bean. Crop Science 37:248-254.

Johnson, William C., 1997. Dissertation: Improving the efficiency of common bean (Phaseolus vulgaris L.) breeding programs using molecular markers.

Johnson, William C., and Paul Gepts, 1998. Segregation for performance in two recombinant inbred populations resulting from inter-gene pool crosses of common bean (Phaseolus vulgaris L.). Euphytica, in press.

Freyre, Rosanna L., Paul Skroch, Anne-Francois Adam-Blondon, Valerie Geffroy, Asgar Shirmohamadali, William C. Johnson, Victor Llaca, Rubens O. Nodari, Pedro Pereira, Siu-Mui Tsai, Joe Tohme, Michel Dron, James Nienhuis, and Paul Gepts. Towards an integrated linkage map of common bean. IV. Correlation among RFLP maps. Submitted.

Johnson, William C., and Paul Gepts. Epistasis and the role of inbreeding depression following wide crosses of common bean. Submitted.

Johnson, William C., Louise E. Jackson, Oswaldo Ochoa, Johann Peleman, Rik van Wijk, Dina A. St.Clair, and Richard W. Michelmore. Genetic control of root architecture and deep water extraction for a shallow rooted crop. In preparation.

Johnson, William C., Louise E. Jackson, Oswaldo Ochoa, Johann Peleman, Rik van Wijk, Dina A. St.Clair, and Richard W. Michelmore. Localization of genes for domestication in lettuce, Lactuca sativa L. In preparation.

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USDA/ARS - PGRU homepage with additional hyperlinks

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