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Treesearch

Pathogenicity of Phytophthora species isolated from rhizosphere soil in the eastern United States

Informally Refereed
Download (PDF 145 KB): https://research.fs.usda.gov/download/treesearch/29901.pdf

Abstract

Pathogenicity of seven Phytophthora species was assessed by inoculation of stem and foliar tissues of oak species (Quercus spp.) native to the eastern United States. Phytophthora cambivora, P. cinnamomi, P. citricola, P. europaea, P. quercina ?like?, P. sp1 and P. sp2 were inoculated into stems of 1-year-old greenhouse seedlings and 2-year-old oaks grown under field conditions. Stem inoculations were conducted for 2-month periods in June and September (summer inoculation) and in October-December (fall inoculation). Stem inoculation was conducted by inserting an agar plug containing mycelium on a U-shaped wound, made aseptically about 3 cm above the root collar. Oak species used for 1-year-old stem inoculations included Q. bicolor, Q. macrocarpa, Q. montana, Q. palustris, and Q rubra; 2-year-old seedlings included Q. alba, Q. montana, Q. palustris, Q. rubra and Q. velutina. Leaf inoculations also were conducted using oak and understory plant species to evaluate the ability of the Phytophthora species to infect foliar tissue. These tests included foliage of the six oak species that were tested as part of the stem inoculation experiments and foliage of Q. alba, Q. imbricara, Q. robur, Castanea dentata, Kalmia latifolia and Rhododendron maximum. Two leaf age categories were used: leaves that were fully developed and up to 3 months in age; and, leaves that were 3 to 6-months old. Wound and non-wounded treatments were applied to each age category.

Parent Publication

Citation

Balci, Y.; Balci, S.; MacDonald, W.L.; Gottschalk, K.W. 2008. Pathogenicity of Phytophthora species isolated from rhizosphere soil in the eastern United States. In: Frankel, Susan J.; Kliejunas, John T.; Palmieri, Katharine M., tech. coords. 2008. Proceedings of the sudden oak death third science symposium. Gen. Tech. Rep. PSW-GTR-214. Albany, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station. pp. 225-226