Permanent address: Univ. of Florida, Agricultural Research and Education Center, Leesburg, FL 32749.
Received for publication 6 June 1985. We gratefully acknowledge plant donations and valuable discussion from C. Klein-Cox (Congdon-Weller Nursery, Clarence, N.Y.) and the excellent technical assistance of S.G. Carpenter and P. Hemstad. 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.