Low volume potato spraying in Maine

Abstract

Various types of sprayers were used to measure the effectiveness of low volume fungicidal sprays for control of late blight. Early experiments compared 100 or more gallons per acre (gpa) with 25 to 50 gpa. Later work involved aerial application and aerial application simulators where 3 gpa or less were used. In these studies, conducted over several years, the late blight organism was artificially introduced and disease development usually was adequate for evaluation of control efficiency. In some experiments insect control data were obtained as were measurements on chemical vine-killing. Evidence of improved fungicidal action through low volume application was observed and further studies on this effect are in progress. In general, fungicidal applications at all gallonages tested were effective if the equipment was operated according to manufacturer's recommendations.