Comparative Efficacy of Methyl Bromide Against Codling Moth (Lepidoptera: Tortricidae) Larvae in ‘Bing’ and ‘Rainier’ Cherries and Confirmation of Efficacy of a Quarantine Treatment for ‘Rainier’ Cherries

Abstract

Susceptibility of third-instar codling moth, Cydia pomonella (L.), to methyl bromide at 6 or 12°C was not significantly affected by the host cultivar of sweet cherry. The 95% CL for the LC50 and LC90s for larvae in ‘Bing’ and ‘Rainier’ cherries overlapped in fumigation tests at either temperature. Sorption of methyl bromide by both cultivars in comparative efficacy studies was substantial (averaging 51.0 and 55.5% for ‘Bing’ and ‘Rainier’ cherries, respectively) for both fumigation temperatures. None of the estimated 10,839 third-instar codling moth treated in ‘Rainier’ cherries in a confirmation test survived fumigation with methyl bromide at 64 g/m3 for 2 h at 6°C. These results showed that methyl bromide fumigation schedules previously approved against codling moth larvae in ‘Bing’ and other sweet cherry cultivars are equally effective against codling moth larvae in ‘Rainier’ cherries.