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

View the project report

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.