Submitted to: Extension Circular
Publication Type: Abstract Only
Publication Acceptance Date: 1/7/2003
Publication Date: 1/13/2003
Citation: Hoitink, H.A.J., Nameth, S.T., Locke, J.C. Control of Phytophthora and Other Major Diseases of Ericaceous Plants. Special Circular 189, Ohio Agricultural Research and Development Center and Ohio State University Extension. 2003. Interpretive Summary:
Technical Abstract: Phytophthora diseases affect many nursery crops. They can be divided into: 1) dieback diseases that involve blights of leaves and shoots and, 2) root and crown rots. Many nursery crops are susceptible. Phytophthora cinnamomi is the most common root rot pathogen. Many Phytophthora species can cause stem dieback and leaf blight diseases, particularly on Rhododendrons and Pieris. Recently, Phytophthora ramorum became note worthy because it causes a severe disease on above ground parts of mature native oak trees in California. It may also infect rhododendron. We examined rhododendrons in Ohio during the past two years for this new pathogen but have not isolated it so far. Plants in the family Ericaceae (rhododendrons, azaleas, etc) in general are listed as most susceptible to Phytophthora species.