Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: 7/30/2005
Publication Date: 7/30/2005
Citation: Rinehart, T.A., Copes, W.E., Cubeta, M.A. 2005. Genetic, pathogenic, and phenotypic characterization of rhizoctonia spp. isolated from container-grown azalea in the southern united states. Phytopathology.
Technical Abstract: Rhizoctonia web blight on containerized azalea is an annual problem during the summer months in the southern U.S. Rhizoctonia spp. were isolated from symptomatic leaf tissue from two nurseries in Mississippi and Alabama during June, July and August of 2002, 2003, and 2004. The internal transcribed spacer region (ITS) of the ribosomal DNA was sequenced from 313 isolates to determine genetic relatedness and a subset of these isolates were further identified using hyphal anastomosis pairing reactions. Frequency distributions of phenotypic traits (color and texture of mycelium on potato dextrose agar), in vitro growth rates at 20 and 30 degrees C, and pathogenicity on leaves of excised stems were evaluated for 182 of the 313 isolates. This is the first comprehensive genetic analysis of binucleate Rhizoctonia spp. on azalea.