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

BUTELER, MICAELA; LOZADA MARIANA; D'ADAMO PAOLA; MELO ROMINA; STADLER, T.

Austral Entomology

Australian Entomological Society

Año: 2016 vol. 55 p. 308 - 315

2052-174X

Secondary plant metabolites such as those present in essential oils can be toxic to herbivorous insects and alsorepel attack, given they play a role in selection and acceptance of host plants. However, few studies have dealtwith the use of plant-based repellents to manage invasive wasps. The objective was to assess essential oils withpotential as wasp repellents, and to gain further insight as to how they affect the learning capacities of theseinsects. Five essential oils were tested on Vespula germanica (Fabricius) wasps in field choice and no-choicetests. When given a choice, foragers avoided the treated baits almost completely. Wind tunnel bioassaysdemonstrated that wasps recognise the repellent essential oils through olfactory cues, leading to a dosedependentdecreased response to the food stimulus. The effect of the repellents on the cognitive ability ofV. germanicaworkerswas also studied in relation to food search efficiency. Naiveworkers landed on the treatedbaits, although it took them longer than to land on control baits. When workers were allowed to forage on a foodbait twice before a repellent was added, an effect on relocation behaviour was observed. The returning workersarriving to a feeding site with essential oil were reticent to land on it, suggesting that there is indeed a repellenteffect and not just masking of the food source. A push?pull system combining attractive baits with the use ofplant-based repellents is a promising management strategy in urban settings for this insect pest.