Exploiting weevil behaviour
for biological control
Gill Prince, Tom Pope1, Jude Bennison2 and Dave Chandler
1
Harper Adams University, Shropshire UK; 2ADAS Boxworth, Cambridge, UK
Vine weevil (Otiorhynchus sulcatus) is a serious pest in
both soft fruit and nursery stock industries. Damage is
caused both by the adults, resulting in characteristic
leaf notching and larvae which feed on plant roots,
corms and tubers.
In collaboration with Harper Adams and ADAS we are
investigating exploiting vine weevil behaviour to
disseminate entomopathogenic fungal spores placed
within the crop environment in artificial refuges.
Initial bioassays showed that adults were susceptible to eight
strains of entomopathogenic fungi when applied directly to
the weevil . The three most virulent strains were used to
bait refuge traps in a laboratory bioassay. Adult mortality
was assessed daily and fungal infection confirmed.
• Fungal conidia were observed on the weevils
within 4 hours and fungal spores were seen
on the bioassay chamber floor, indicating
that they had been carried out of the trap by
weevils.
• Metarhizium anisopliae 275.86 killed 50% of
the weevil population within 14 days.
• All of the isolates tested produced conidia
on adult cadavers . The majority occurred
between the body segments and leg joints.
• There was evidence of avoidance behaviour
by adult weevils with one isolate of
Beauveria bassiana (1749.11).
Acknowledgements
Thanks to the Chemicals Regulations Directorate (CRD) for funding this research.
Warwick Crop Centre
www.warwick.ac.uk/go/wcc