Studies on Integrated Control of Apple Pests1

Abstract

Studies on integrated control of apple pests were conducted in Door County, Wisconsin, from 1960 through 1962. Ryania, Bacillus thuringiensis Berliner, phosphamidon, and lead arsenate were used in various combinations and dosage rates. Carbaryl and captan were used as the insecticide and fungicide check, respectively. Apples harvested from the ryania-Bacillus plot were 88 and 86% free of insect injury in 1960 and 1961, respectively, compared with 97 and 95% in the carbaryl plot and 37 and 45% in the captan plot. Ninety-one percent of the apples in the lead arsenate-ryania plot and 94% of those from the lead arsenate-phosphamidon plot were devoid of insect injury in 1961, compared with 95% for the carbaryl program. In 1962, apples from the ryania-Bacillus-lead arsenate plot were 94% free of insect injury compared with 95, 96 and 80% from the lead arsenate-phosphamidon, carbaryl, and captan plots, respectively. The codling moth, Carpocapsa pornonella (L.), red-banded leaf roller, Argyrotaenia velutinana (Walker), and eye-spotted bud moth, spilonota ocellana (Denis & Schiffermuller), in that order, were responsible for most of the insect injury, except in 1962 when the codling moth was a minor problem. The highest two-spotted spider mite, Tetranychus urticae (Koch), population occurred in the carbaryl plot where phytoseiids were practically eliminated, The European red mite, Panonychus ulmi (Koch), increased progressively each year of the study in the plot where B. thuringiensis was used, The high population which occurred in 1962 caused economic injury to the foliage and fruit. The lead arsenate-phosphamidon program adversely affected both the phytophagous and predaceous mite populations. Six phytosciid species were collected in the captan plot during 1960. Amblyseius fallacies (Carman) and Typhlodromus Caudiglans (Oudemans) were the most abundant. The ryania-lead arsenate program, was considered the most effective for integrated control of apple pests because of its overall effectiveness for both direct and indirect pests without adversely affecting natural enemies of the latter.