Pierce's Disease
Research Updates

piercesdisease.cdfa.ca.gov

What is Pierce's Disease?

Pierce's Disease is a bacterial infection, which is spread by bugs that feed on grapevines, particularly the "glassy winged sharpshooter." Grapevines that become infected with PD can quickly become sick and die.

glassy-winged sharpshooter

Biology of Gonatocerus tuberculifemur (Hymenoptera : Mymaridae), an egg parasitoid of the sharpshooter, Tapajosa rubromarginata (Hemiptera : Cicadellidae)


  • Author(s): Jones, Walker; Logarzo, Guillermo; Virla, Eduardo;
  • Abstract: Biological traits of a prospective candidate for biological control of the glassy-winged sharpshooter (GWSS), Homalodisca coagulata (Say) (Hemiptera: Cicadellidae), in the United States are herein reported. The mymarid wasp, Gonatocerus tuberculifemur (Ogloblin), is an egg-parasitoid native to Argentina and its first known host is Tapajosa rubromarginata (Signoret), a species related to GWSS. Laboratory studies were made in Tucuman and Buenos Aires Provinces, Argentina. Seven generations were maintained in the laboratory, and only one adult emerged per host egg. The average parasitism rate was 71.6% of total eggs. Although eggs of all ages (4 to 190 h old) were parasitized, wasps did not emerge from eggs over 96 h old. The percentage of wasp emergence was 66.5% from eggs between 4 and 72 h old. Over the seven generations that G. tuberculifemur was reared, the parasitism rate ranged between 55-84%. This percentage of emergence increased as the parasitoid generations progressed. The duration of development from oviposition to adult emergence of G. tuberculifemur was 12.6 ± 1.8 days (range 11.4-13.0) at 22.5-27.5° C and 70-80% RH. The duration of development was significantly affected by sex and temperature. Males developed faster than females (12.2 vs. 12.8, respectively). The sex ratio was not significantly different from 1:1. Average adult longevity was 6.73 ± 3.93 days fed on honey. Male and female longevity was not significantly different. Oviposition and mating behavior are described.
  • Publication Date: Mar 2005
  • Journal: Florida Entomologist