Received for publication 13 Jan. 1988. T.v.d.Z. sincerely appreciates and thanks the following persons for their invaluable assistance in this project: in Romania, N. Braniste at the Trustul Pomicul-turii in Pitesti, M. Straulea at the Cercetari Horticole in Cluj, and O. Tudosescu, Director of the Fruit Production Station in Voinesti; in Poland, S. A. Pieniazek, past director of the Research Institute of Pomology in Skierniewice, and T. Ja-cyna, Institute of Pomology in Albigowa; in Hungary, A. Terpo, director of the Botanical Garden “Soroksar”, B. Szilagyi, Technical Advisor of the National Center of State Farms in Budapest, and G. Zboray for translation services; in Czechoslovakia, J. Vondracek, Fruit Research Station “Techobuzize” in Ploskovice; and, in the United States, W.R. Povish, for all phases of logging in the shipments and careful handling of the budding operations as well as maintaining and virus indexing the trees at the U.S. Plant Introduction Station, Glenn Dale, Md. The cost of publishing this paper was defrayed in part by the payment of page charges. Under postal regulations, this paper therefore must be hereby marked advertisement solely to indicate this fact.