Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 12/1/2010
Publication Date: 6/1/2012
Citation: Weiland, G.E. 2012. Soil-pest relationships. In: Cram M.M., Frank M.S., Mallams K.M. Forest Nursery Pests. Washington (DC): USDA Forest Service Agriculture Handbook 680: 129-131.
Technical Abstract: Pythium root rot is a disease that is found in agricultural and nursery soils throughout the United States and Canada. It is caused by several Pythium species, and the symptoms are typified by leaf or needle chlorosis, stunting, root rot, and plant death. The disease is favored by wet soils, overcrowding, and excessive fertilization. Diagnosis of the disease is confirmed by isolation of the pathogen into culture or with appropriate test kits. Disease management is focused on avoiding poorly-drained soils and other environmental conditions that favor disease. Rotations to bare fallow, application of fungicides for oomycetes, and fumigation are also effective.