REPRODUCTIVE BIOLOGY AND PHYSIOLOGY OF GLASSY-WINGED SHARPSHOOTER

• Author(s): Peng, Frank; Hummel, Natalie; Toscano, Nick;
• Abstract: The glassy-winged sharpshooter (GWSS), Homalodisca coagulata (Say), is a serious pest of many tree and vine crops (Turner and Pollard 1959, Nielson 1968). The main concern of the presence of the GWSS in California is that this insect is an efficient vector of the bacterium, Xylella fastidiosa, which causes vascular disease in multiple crops, including grapes, citrus, and almonds, along with horticultural plants, including oleander and mulberries (Meadows 2001, Hopkins 1989, Purcell and Hopkins 1996). An adult GWSS need only encounter the Pierces disease causing bacterium, X. fastidiosa, once while feeding on an infected plant and it will then be a vector of X. fastidiosa for the rest of its life (Frazier 1965, Purcell 1979, and Severin 1949). Little is known about the reproductive biology of the GWSS. It has been reported that GWSS has two generations per year in Southern California (Blua et al. 1999). Oviposition occurs in late winter to early spring, and again in mid-to-late summer. Adult females live several months and lay small eggs side by side in groups of about 10, ranging from 1 to 27 (Tuner and Pollard 1959). The greenish, sausage-shaped eggs are deposited in the leaf epidermis of the host plants. Our research is focused on the reproductive morphology and physiology of the GWSS. We are examining the seasonal differences in female and male GWSS reproduction between summer and overwintering populations by studying ogenesis and spermatogenesis cycles. This knowledge is important in determining how GWSS might choose plant hosts in the landscape, which and why these host plants are particularly suitable for GWSS ovarian development, and finally how control measures might best be implemented based upon season and stage of reproductive development. Better knowledge of reproductive biology might also lead to better decision support including improved choices of chemical or non-chemical approaches to GWSS control.
• Publication Date: Dec 2002
• Journal: 2002 Pierce's Disease Research Symposium