An investigation of available Cydonia (Cydonia oblonga Mill., quince, membrillo) germplasm by isozyme staining of anionic polyacrylamide gradient electrophoresis gels is described. The isozymes of acid phosphatase, esterase, peroxidase and phenol oxidase showed most diversity and usefulness for this purpose. Eleven groups of quince and two groups of x Pyronia (quince-pear crosses) were distinguished by their isozyme patterns. These patterns distinguish between groups of clonal accessions, and the patterns were constant for each accession during the test period (December, 1986 to August, 1987). Thus, these patterns were considered to represent genetic characteristics suitable for identification purposes. The diversity of isozyme patterns was much less than in Corylus and Pyrus populations previously sampled; and less than that of a restricted pool of apple cultivars previously examined.
Contribution of Oregon State Experiment Station in cooperation with ARS/USDA, and published as Oregon Agricultural Experiment Station Technical Paper No. 8441. Part of a thesis to be submitted by the senior author in fulfillment of the requirements for the Ph.D. degree. The authors would like to acknowledge: M.N. Westwood (Professor Emeritus, Oregon State University) for advice and encouragement, H.C. Lisle of Norwalk, Ohio; Oregon Rootstocks Nursery, Woodburn, Oregon; and W. Povish of the US Plant Introduction Station, Glen Dale, Maryland for supplying plant materials for comparison with National Clonal Germplasm collection. Thanks are also due to J. Chandler, P. Robbins and J. Snead for field and greenhouse support; Sigma Chemical Company for their kind gift of reagents and the Horticultural Research Institute for equipment funding. This material is based upon work supported by the U.S. Department of Agriculture, Agricultural Research Service, under specific Cooperative Agreement No. 58-0401-7-00154.
2Graduate Student, Associate Professor, Research Assistant and Professor resp., Department of Horticulture, Oregon State University, Corvallis, OR 97331
3Chemical and Agricultural Division, Abbott Laboratories, North Chicago, Illinois 60064
4National Clonal Germplasm Repository, 33447 Peoria Rd., Corvallis, OR 97333
5Instituto National de Technologia Agropecuaria, Ministerio de Agricultura, Buenos Aires, Argentina