Rubidium as a Marker and Simulated Inoculum for the Black-Faced Leafhopper, Graminella nigrifrons1 , the Primary Vector of Maize Chlorotic Dwarf Virus of Corn 2

Abstract

Aqueous sprays of rubidium chloride (RbCl) were applied to host plants of the black-faced leafhopper Graminella nigrifrons (Forbes) for determining the feasibility of Rb tagging in monitoring the rate of maize chlorotic dwarf virus (MCDV) dispersal by its leafhopper vector. Concentrations up to 18,000 ppm RbCl had no effect on mortality or development of the vector species. The properties of plant uptake and translocation of Rb provide a new mechanism for MCDV dispersal studies since Rb can be acquired by G. nigrifrons in a manner similar to virus acquisition and detected in vectors during a time span corresponding to the inoculative period for MCDV. Detection of Rb levels in vectors was easily facilitated by X-ray fluorescence and atomic absorption spectroscopy.