Apple, Evaluation of Pyrellin E.C. in Dip Water to Control Redbanded Leafroller and Tufted Apple Bud Moth Larvae on Apples Before Placement in Storage, 1990

Abstract

Abstract Two tests were conducted to gather preliminary data on the possibility of controlling RBLR adhering to fruit before it is placed in storage. Since most apples enter packing sheds via a water dump, and since the insecticide under test is registered for use on harvested produce, including fruit, adding the toxicant to the dip water appeared to be a possible, practical control method. Test No. 1: Thirty apples with RBLR larvae adhering to the surfaces of the fruit were obtained from a bin of drop apples collected from under the trees in a commercial apple orchard on 20 Oct. Larvae were disturbed as little as possible during collection and leaves covering the larval sites were left in place. Each infested apple was marked by sticking an aluminum shingle nail into the fruit some distance from the location of the insect. The infested fruit was randomly distributed among the fruit filling a one bushel packing crate. Fifty gallons of untreated well water was placed in a galvanized tank and 12 fl. oz. of Pyrellin E.C. was thoroughly mixed with the water. A wooden cover was held on top of the fruit to keep it in the crate while the crate was immersed in the pesticide solution for one minute. Following dipping, the crate was placed on an outside, roofed, loading dock where it remained until the larvae were examined twenty-four hours later. Test No. 2: This test, conducted on 26 Oct, was similar in most respects to test No. 1. However, the apples came from a different orchard. In test 2, a plastic garbage bag was placed under the crate after dipping in an attempt to capture exiting larvae. Prior to this test the grower had reported a heavy population of tufted apple bud moth, however it was found to be RBLR when larvae from the test were collected.