COMPARISON OF APPLICATION METHODS FOR TOBACCO BUDWORM CONTROL, 2010

Abstract

Anthranilic diamide insecticides, two of which have recently been registered for use in tobacco, may be more persistent in plant tissue and move within leaf tissue to a great extent than other registered chemistries. These characteristics may allow anthranilic diamaide insecticides to be applied using different methods than standard materials used against TBW. Standard insecticide application methods for TBW control recommend a volume of 30 gpa water applied with 60 psi pressure using solid or hollow cone nozzles. Using one of the registered anthranilic diamaide insecticides registered in tobacco (Belt, Bayer CropScience) applied at a rate of 3.0 fl oz/acre, we compared 4 application volumes (5, 10, 20, and 50 gpa water) applied at 2 pressures (30 and 60 psi) to determine if applications at lower volumes and pressures were as effective as those at higher volumes with greater pressure. Greenhouse grown tobacco plants were transplanted on 4 May. Plants were treated with 0.8 fl oz/1000 plants Admire Pro 5 d prior to transplant to control early season tobacco flea beetle (Epitrix hirtipennis) and green peach aphid (Myzus persicae) populations. Four row plots, 50 ft in length, were established immediately after transplant. Plots were 0.018 acres each. Each treatment was replicated 4 times, and plots were arranged in an RCBD, blocked by replicate. Six wk after transplant, 10 plants each in rows 2 and 3 of each plot were infested with laboratory reared 2 instar TBW larvae, purchased as eggs from Chesapeake PERL (Savage, MD). Treatments were applied the d after larval infestation. Larval survival and leaf area consumed were rated 3, 7, and 14 d after foliar treatments were applied. Treatments were applied using a single nozzle boom fitted with a TG3 solid cone tip and powered by a CO2 pressurized backpack sprayer. Data were analyzed via Proc Mixed (SAS v. 9.1.3; Cary, NC) with replicate as a random variable. Each date was analyzed separately, not as a repeated measure.