VIEW ARTICLE

Etiology

A Simplified Procedure for the Purification of Curly Top Virus and the Isolation of Its Monomer and Dimer Particles. Richard C. Larsen, Research associate, U.S. Department of Agriculture, Agricultural Research Service, Salinas, CA 93915; James E. Duffus, research plant pathologist, U.S. Department of Agriculture, Agricultural Research Service, Salinas, CA 93915. Phytopathology 74:114-118. Accepted for publication 26 July 1983. 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, 1984. DOI: 10.1094/Phyto-74-114.

Curly top virus was purified from shepherd' s purse plants (Capsella bursa-pastoris) 4- 5 wk after inoculation with viruliferous beet leafhoppers (Circulifer tenellus). The virus-containing sap was clarified with chloroform, the virus precipitated and concentrated by polyethylene glycol, and subjected to two cycles of high-speed ultracentrifugation. Monomer and dimer particles were isolated from partially purified preparations by sucrose density gradients. Infectivity assays indicated that the dimer particle is required for infection. Virus yields obtained averaged 500 μg/kg of plant material. The A_{260-280 nm} ratio for dimers was ~1.4.