A Gravel Container Base for Control of Phytophthora Dieback in Rhododendron Nurseries. C. R. Kuske, Former Graduate Research Assistant, Department of Plant Pathology, North Carolina State University, Raleigh 27650. D. M. Benson, Associate Professor, and R. K. Jones, Professor, Department of Plant Pathology, North Carolina State University, Raleigh 27650. Plant Dis. 67:1112-1113. Accepted for publication 17 April 1983. Copyright 1983 American Phytopathological Society. DOI: 10.1094/PD-67-1112.

Under growing conditions typical of commercial nurseries, lesion incidence, dieback, and plant mortality caused by Phytophthora spp. was significantly less in rhododendrons grown on an infested pine-bark container base covered 5–7 cm deep with gravel than on plants grown on an infested pine-bark container base alone. The number of lesions per plant for plants grown on a pine bark or gravel container base averaged 2.8 and 0.4, respectively. Plant mortality averaged 70 and 5%, respectively, during the 4-mo growing season.