Monday, December 10, 2007 - 8:53 AM

A novel role for Wolbachia (Rickettsiales: Rickettsiaceae) in plant-insect interactions

Kelli Barr,, Leonard Hearne,, Bruce Hibbard,, and Georgia Davis, University of Missouri, Division of Plant Sciences, 1-31 Agriculture Bldg, Columbia, MO

Diabrotica virgifera virgifera (LeConte) which is infected with Wolbachia, is the most significant and widespread pest to maize in North America and Europe. It has repeatedly surmounted chemical and cultural control measures in far fewer generations than any other crop pest. Wolbachia are obligate intracellular bacteria which seem to be limited to ecdyzoan hosts. Many infected hosts induce or vector serious human diseases resulting in the loss of millions of lives annually. Wolbachia also infect several insect species of economical importance which cost the U.S. billions of dollars per year. It is believed that the presence of Wolbachia in insects serves as a reproductive barrier by inducing cytoplasmic incompatibility between Wolbachia infected and non-infected populations. Evidence suggests that insect mitochondrial mutation rates can be over ten times greater in Wolbachia infected populations than non-infected counterparts. Recent reports of Wolbachia mediating genetic response in mammals on a tertiary level led us to believe that Wolbachia may play a role in the maize-rootworm association. A microarray experiment was performed to determine if Wolbachia are involved in the maize-rootworm association. Here we discuss the dramatic effects of Wolbachia on the defense response of maize.

Species 1: Coleoptera Chrysomelidae Diabrotica virgifera virgifera (western corn rootworm)
Species 2: Rickettsiales Rickettsiaceae Wolbachia (Wolbachia)