|Littlefield, Jeffrey - MONTANA STATE UNIVERSITY|
Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: March 15, 2006
Publication Date: June 1, 2006
Citation: Bruckart, W.L., Eskandari, F., Littlefield, J., Mcmahon, M.B., Luster, D.G. 2006. Discovery of cercosporella leaf spot on russian knapweed in montana. Phytopathology. 96:S191. Technical Abstract: Acroptilon repens (Russian knapweed) is a major weed in the western United States. A Turkish isolate of Cercosporella acroptili has been a candidate for biological control of A. repens, undergoing evaluations in the containment greenhouse at the FDWSRU. In August, 2005, leaf spot disease symptoms were noted on samples of A. repens collected in Montana that were infected by Puccinia acroptili. A Cercosporella sp. was isolated that was pathogenic on inoculated A. repens in greenhouse tests. The pathogen was identified as C. acroptili on the basis of fungal morphology and symptomatology on A. repens. This isolate was identical to both the type specimen and the candidate isolate from Turkey (FDWSRU #98-001) on the basis of morphological and molecular characteristics. Discovery of C. acroptili in Montana has caused reconsideration of program objectives involving continued evaluation of the Turkish isolate for biological control. Development of the U.S. isolate for biological control of A. repens may now be a possibility.