Translator Disclaimer
1 August 2000 Effective Fall Treatment of Varroa jacobsoni (Acari: Varroidae) with a New Formulation of Formic Acid in Colonies of Apis mellifera (Hymenoptera: Apidae) in the Northeastern United States
Author Affiliations +
Abstract

New formulations of formic acid and thymol, both individually and in combination with various essential oils, were compared with Apistan to determine their efficacy as fall treatments for control of V arroa jacobsoni (Oudemans), a parasitic mite of the honey bee, Apis mellifera L. Percent mite mortality in colonies treated with 300 ml of 65% formic acid averaged 94.2 ± 1.41% (least square means ± SE, n = 24), equivalent to those receiving four, 10% strips of Apistan (92.6 ± 1.79%, n = 6). Treatment with thymol ( n = 24) resulted in an average mite mortality of 75.4 ± 5.79%, significantly less than that attained with Apistan or formic acid. The addition of essential oils did not affect treatment efficacy of either formic acid or thymol. The ratio of the coefficients of variation for percentage mortality for the formic acid (CVFA) and Apistan (CVA) groups was CVFA/CVA = 0.66. This indicates that the formic acid treatment was as consistent as the Apistan treatment. Thymol treatments did not provide as consistent results as Apistan or formic acid. Coefficient variation ratios for percentage mortality for the thymol group (CVT) with the Apistan and formic acid groups were CVT/CVA = 4.47 and CVT/CVFA = 6.76, respectively. In a second experiment, colonies received a 4-wk fall treatment of either 300 ml of 65% formic acid ( n = 24) or four, 10% strips of Apistan ( n = 6). The next spring, mite levels in the formic acid group (554.3 ± 150.20 mites) were similar to those in the Apistan treatment group (571.3 ± 145.05 mites) ( P = 0.93). Additionally, the quantities of bees, brood, pollen, and nectar/honey in the two treatment groups were not significantly different ( P ≥ 0.50 each variable). These results suggest that formic acid is an effective alternative to Apistan as a fall treatment for varroa mites in temperate climates.

NICHOLAS W. CALDERONE "Effective Fall Treatment of Varroa jacobsoni (Acari: Varroidae) with a New Formulation of Formic Acid in Colonies of Apis mellifera (Hymenoptera: Apidae) in the Northeastern United States," Journal of Economic Entomology 93(4), 1065-1075, (1 August 2000). https://doi.org/10.1603/0022-0493-93.4.1065
Received: 1 November 1999; Accepted: 1 June 2000; Published: 1 August 2000
JOURNAL ARTICLE
11 PAGES

This article is only available to subscribers.
It is not available for individual sale.
+ SAVE TO MY LIBRARY

SHARE
ARTICLE IMPACT
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top