Control of the Codling Moth with Guthion and CM Granulosis Virus, 1994

Guthion and two formulations of CM granulosis virus, a powder (CGI-9401) and liquid (CGI-9405), were evaluated for their ability to control CM over the entire season. Milk and 45 ml of NU-FILM-P were added to the 25-gal mixture of both virus formulations before application. Powdered milk was used first generation at 1 lb/25 gal, and liquid milk was used second generation at 1 gal/25 gal. The test was conducted in an apple orchard at the Tree Fruit Research and Extension Center. The trees were 15-yr-old spur type ‘Delicious’ on dwarfing roots. Treatments were applied to two-tree plots replicated five times using a RCB design. All treatments were applied with a handgun sprayer at 300 psi to the point of drip, simulating a dilute spray of approximately 400 gpa. The CM granulosis virus was applied at intervals of 100 degree days following the first application against each CM generation. The first application of all treatments against the first and second CM generation was based on an accumulation of 250 (11 May) and 1200 (15 Jul) degree days, respectively, after first moth capture in pheromone traps. The posttreatment evaluation was made on 30 Aug. One hundred apples from one tree per plot were examined, and the number of CM injured fruit was recorded.