Present address: Instituto di Coltivazioni, Arboree di Pisa, Pisa, Italy.
Received for publication 30 Oct. 1985. A contribution of the Georgia Agricultural Experiment Station, College Station, Athens. This research was supported by State and Hatch Act funds allocated to the Georgia Agricultural Experiment Station, College Station, Athens, by grant No. 1-43-79 awarded by the U.S.-Israel Binational Agricultural Research and Development Fund (BARD), by the National Science Foundation (NSF) grants Deb. 77-15845 and Deb. 80-20312 awarded to the Duke Univ. Phytotron, Durham, N.C., and by a C.N.R. NATO Fellowship (No. 203.6.25) awarded to G.S. Appreciation is expressed to the staff of the Duke University Phytotron for their assistance. 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.