A Granulosis Virus Disease of the Western Grape Leaf Skeletonizer and its Transmission

Abstract

Since 1950 the University of California has maintained a program designed to evaluate the effectiveness of certain insect parasites in the control of the western grape leaf skeletonizer, Harrisina brillians B. & McD., in San Diego County, California. During this time, all sustained efforts to produce parasites in quantities for field release have failed because of recurrent outbreaks of a disease of the skeletonizer larvae. The causative agent of this disease was identified by Steinhaus and Hughes (1952) as a granulosis virus.