Behavioral responses of Vespula germanica (Hymenoptera: Vespidae) (Fabricius) wasps exposed to essential oils

MICAELA BUTELER; MARIANA LOZADA; PAOLA D´ADAMO; ROMINA LUZ; TEODORO STADLER

Austral entomology

WILEY-BLACKWELL PUBLISHING, INC

Año: 2015

Secondary plant metabolites such as those present in essential oils can be toxic to herbivores and also repel attack, given they play a role in selection and acceptance of host plants. However, few studies have dealt with the use of plant based repellents to manage invasive wasps. The objective was to assess essential oils with potential as wasp repellents, and to gain further insight as to their mode of action. Five essential oils were tested on Vespula germanica wasps in field choice and no-choice tests. When given a choice, foragers avoided the treated baits almost completely Wind tunnel bioassays demonstrated that wasps recognize the repellent essential oils through olfactory cues leading to a dose dependent decreased response to the food stimulus. The effect of the repellents on the cognitive ability of V. germanica workers was also was studied in relation to food search efficiency. Naive workers landed on the treated baits, although it took them longer than to land on control baits. In another experiment, workers were allowed to forage on a food bait twice after which a repellent was added. The returning workers arriving to a feeding site with essential oil repellents were reticent to land on it suggesting that there is indeed a repellent effect and not just masking of the food source. These results suggest that a push-pull system combining attractive baits with the use of plant based repellents is a promising management strategy for this insect pest.