Systemic Insecticides for Control of the Black-Faced Leafhopper, Graminella nigrifrons, and Effect on Corn Stunt Disease1

Abstract

Three soil systemic insecticides, Baygon® (o-isopropoxphenyl methylcarbamate), disulfoton, and Furadan® (Niagara 10242) (2,3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate), were tested in 1967 for their efficacy against Graminella nigriforons (Forbes), vector of com stunt virus. Experimental plots (0.25 acre) in 3 replications of a randomized complete block design were treated with insecticide as in-furrow applications only or as in-furrow plus side-dress applications at 1 lb/acre 5 weeks after planting. Significantly fewer leafhoppers were collected in Furadan treatment plots and in the Baygon furrow plus side-dress treatment than in the other treatments, Vector control was reflected in disease incidence data; those treatment plots with smaller leafhopper populations had fewer diseased plants than plots harboring larger vector populations. Side-dress applications of Furadan and Baygon 5 weeks after planting increased the efficiency of these materials to a higher level of leafhopper control. Furadan plots receiving a supplemental side-dress application did not have a lower incidence of disease compared with plots treated with this insecticide in-furrow only. Side-dressing with Bagron and disulfoton reduced disease incidence; however these 2 materials were in general less effective than Furadan.