New research has found that these notorious garden pests are attracted to apple sauce volatiles, opening new doors for precision monitoring. The study, “An Apple a Day Does not Keep the Weevils Away: Enhancing Vine Weevil Monitoring with Fruit-Based Volatiles,” used a combination of behavioural and chemical‑analytical methods to demonstrate that apple sauce could serve as an effective lure.
The Researchers carried out laboratory and glasshouse experiments to test the response of adult vine weevils (Otiorhynchus sulcatus) to apple sauce aromas. In laboratory trials, a Y‑tube olfactometer setup allowed individual weevils to choose between an arm carrying apple sauce volatiles and a control arm (no volatiles). They tested a range of apple sauce doses (0.1 g, 1 g, 10 g, 20 g) to see how strength of the aroma influenced behavioural response.
At the same time, headspace volatile collections from apple sauce samples were analysed using gas chromatography coupled to mass spectrometry, and paired with electroantennographic detection to detect which volatile compounds elicited an electrical response from the weevils.
To validate the attraction in a more realistic setting, the team placed apple‑sauce–baited refuges in a glasshouse environment and monitored how many weevils settled in baited vs. unbaited refuges. They also tested combinations of apple sauce with plant material (Fortune’s spindle) to see if synergy occurred.
This is the first study to show that simple fruit‑derived volatiles can influence vine weevil behaviour in a way that may be harnessed for pest monitoring. The findings suggest that apple sauce, or its volatile components, could form the basis of a novel semiochemical lure to improve trap effectiveness and early detection of infestations.
The findings of this study could be used to enhance integrated pest management strategies by providing a low‑cost, effective monitoring tool for growers facing vine weevil pressure.
Dr David Hall, Professor of Chemical Ecology at the Natural Resources Institute, University of Greenwich said:
"Vine weevil is a widespread pest in the UK, affecting over 150 plant species, including soft fruits and ornamental crops.
“Adult weevils are nocturnal and larvae feed on roots underground, making infestations hard to detect until significant damage occurs.
“There are currently no effective attractants for vine weevil and this work could lead to development of a really attractive bait for traps to monitor and control vine weevil.”
Read the full paper here
