Advancing Maggot Control in Onion and Cabbage with Reduced-Risk Insecticides

Commodities

• Vegetables: cabbages, onions

Practices

• Pest Management: biological control, chemical control, integrated pest management

Maggots (Delia spp.) are devastating below-ground pests
of onions and cabbage in the Northeast. These crops are among the
most valuable vegetable crops in this region, and damage can
cause yield losses of up to 50%. Over one-third of the onion
acreage and nearly all of the cabbage acreage are transplanted,
and growers typically relied on at-planting applications of
chlorpyrifos to control maggots. The EPA banned chlorpyrifos in
2022, and now there is a demand to identify effective
insecticides that will protect transplanted onion and cabbage
fields from maggots. Research is needed to identify reduced-risk
insecticides that are effective against maggots as well as safe
for pesticide applicators and the environment. Additionally,
further research is needed to examine the impact of
entomopathogenic fungi (EPF) and entomopathogenic nematodes (EPN)
as insecticides for controlling maggots in transplanted crops.
Anticipated benefits from this project include improving crop
production by decreasing pest damage with safer pest management
solutions for applicators and the environment and mitigating
resistance development by identifying a series of insecticides
that could be used in rotation strategies.

The goal of this project is to identify reduced-risk insecticides
to protect onion and cabbage transplants from maggot pests that
are also safe for pesticide applicators and sustainable for these
cropping systems. To achieve this goal, I propose the following
objectives: 

1. Identify reduced-risk insecticides applied as tray drenches
   to control onion maggots (D. antiqua) in onions. We
   hypothesize that all insecticides will provide an acceptable
   level of onion maggot protection.
2. Identify reduced-risk insecticides applied as tray drenches
   to control cabbage maggot (D. radicum) in cabbage.
   We hypothesize that all insecticides will provide an acceptable
   level of cabbage maggot protection.