Received for publication December 20, 1971. Paper No. 3648 of the Journal Series of the North Carolina State University Agricultural Experiment Station, Raleigh.
Professor of Horticultural Science and Graduate Research Assistant, respectively.
Azalea plants were donated by Blackwell Nurseries, Semmes, Alabama. The research was conducted in the Southeastern Plant Environment Laboratories and the authors acknowledge the Phytotron staff, R. J. Downs, Director, and NSF Grant 19650.