Halyomorpha halys, (the brown marmorated stink bug, BMSB), is a high-concern invasive species causing severe damage to orchards in many countries outside its native Asian range. Control options matching both effectiveness and sustainability are currently lacking. Inhibitors of
chitin biosynthesis might be exploited for integrated management programs because of the overall better ecotoxicological profile in comparison with most neurotoxic
insecticides used so far against BMSB. In this study, the activity of
triflumuron, a benzoylphenyl
urea hampering
chitin biosynthesis, was tested on BMSB in laboratory and field conditions. In laboratory bioassays, the
insecticide was sprayed on potted peach plants (30 cm high) and residues were aged in a glasshouse for 0, 7, 14, and 21 d. Then, third-instar bugs were placed on the plants and continuously exposed to residues. Mortality was scored after 7, 14, and 21 d exposure.
Triflumuron caused significantly higher mortality on BMSB nymphs in comparison with water controls at all aging periods. Moreover, aging of residues up to 21 d did not cause any significant reduction of activity. Field experiments were also carried out in 2019 in eight pear orchards.
Injuries to fruits at harvest were compared between plots where
triflumuron was added to
insecticide sprays against BMSB and control plots managed exactly in the same way but without any
triflumuron treatment. An overall mean of 9.99 ± 1.98% stink bug injured fruits was detected in plots managed with the strategy including
triflumuron, whereas 19.45 ± 3.55% of fruits were injured in plots assigned to controls.