by Becky Sideman, UNH Extension Vegetable & Berry Specialist
Pepper maggot (Zonosemata electa) is a pest that is found throughout southern New England; but in recent years, it has been found in several locations in southern New Hampshire as well. Peppers growing in southern counties (Cheshire, Rockingham and Hillsborough) may experience this pest, and should know what to look for.
The pepper maggot adult is a fly with striped wings. It lays its eggs in pepper fruit, producing characteristic “sting” marks on the fruit, typically in July. The eggs hatch within the fruit, producing maggots that feed within the fruit (and reduce marketability). This is not the same pest as European corn borer, which is frequently found within pepper fruit as well. The July 20, 2017 issue of UMass Veg Notes has an excellent article that discusses both pepper maggot and European corn borer damage in pepper.
It is difficult to use traps to monitor this pest, because the effective trapping protocols require that traps be installed high up in trees near production fields. However, pepper maggot is highly attracted to small round peppers, such as the varieties Cherry Bomb. Work in CT by Jude Boucher showed that these varieties can be successful used as a perimeter trap crop to protect other varieties of pepper from the pepper maggot. Jude also has found that these varieties work as an indicator, telling you when the pepper maggot is present.
This year, we have indicator peppers at our research farm in Durham, and are keeping an eye on them. Indicator plants are also in use at commercial farm sites in southern NH; Alan Eaton tells me that stings were first observed in Hillsborough county this week (July 20, 2017), suggesting that the pepper maggot fly is active now. If you have pepper fields and are in these southern locations, keep an eye out for this pest.