Newly Discovered Plant Hosts of Spiroplasma citri. K. W. O’Hayer, Section of Economic Entomology, Illinois Natural History Survey, Champaign 61820. G. A. Schultz, and C. E. Eastman, Section of Economic Entomology, Illinois Natural History Survey, Champaign 61820, and J. Fletcher, Department of Plant Pathology, University of Illinois, Urbana 61801. Plant Dis. 68:336-338. Accepted for publication 14 December 1983. Copyright 1984 The American Phytopathological Society. DOI: 10.1094/PD-68-336.

Circulifer tenellus, injected with an Illinois isolate of Spiroplasma citri obtained from brittle root-diseased horseradish (Armoracia rusticana), transmitted the spiroplasma to yellow rocket (Barbarea vulgaris), wild mustard (Brassica kaber), and shepherd’s purse (Capsella bursa-pastoris). Circulifer tenellus that had fed on experimentally infected yellow rocket, wild mustard, or shepherd’s purse transmitted S. citri to plants of the same species and to horseradish. These weeds, new additions to the host list of S. citri, are the first wild plant species common in the Midwest that have been shown capable of serving as sources for transmission of this spiroplasma.