Susceptibility of Yellow Starthistle to Selected Plant Pathogens. J. M. Klisiewicz, Research Plant Pathologist, USDA, ARS, Department of Plant Pathology, University of California, Davis 95616. Plant Dis. 70:295-297. Accepted for publication 9 October 1985. This article is in the public domain and not copyrightable. It may be freely reprinted with customary crediting of the source. The American Phytopathological Society, 1986. DOI: 10.1094/PD-70-295.

Susceptibility of the widespread weed yellow starthistle (Centaurea solstitialis) to several plant pathogens was investigated. Starthistle plants developed symptoms from disease incited by Fusarium oxysporum f. sp. carthami, Verticillium dahliae, Phytophthora spp., Botrytis cinerea, and Sclerotinia sclerotiorum. Except with B. cinerea, diseases incited by the pathogens were frequently lethal to the plants. Alfalfa (AMV), lettuce (LMV), and turnip (TuMV) mosaic viruses were transitted to starthistle plants by aphids and mechanical inoculation. Mosaic, leaf abnormalities, and moderate to severe stunting were common symptoms induced by the viruses. Some plants infected with LMV or TuMV died in the rosette stage. TuMV had the most adverse effect on starthistle plants.