Striped Cucumber Beetle

Striped cucumber beetle is a common and difficult recurring problem facing many growers across the northern United States. These pests feed on the leaves, roots, and fruit of cucurbits. When the beetle count is high, early in the season, it can kill newly emerging direct seeded plants. They can cause enough damage to transplants to reduce yields if the plants survive to maturity.

Later in the season, adults feed on fruit, decreasing marketability

In addition to these already frustrating problems, striped cucumber beetle is a host for both bacterial wilt and squash mosaic virus. Both of these diseases reduce yield and marketability and eventually terminate the plant entirely. There are currently no insecticides effective against striped cucumber beetle available for certified organic farmers, and organic cultural practices for beetle management are not yet fully developed. We are working to close that gap.

Two cultural practices with promise for striped cucumber beetle management are early use of floating row covers and perimeter trap cropping. Row covers are suitable for plantings of a quarter acre or less, while perimeter trap cropping works best for larger acreages. Row covers provide a physical barrier that prevent beetles from damaging plants early on, but must be removed at flowering for crops requiring pollination. They require a fair amount of labor to take on and off and they interfere with timely cultivation for weed control. We’ll examine the costs and benefits of using row covers for striped cucumber beetle management.

In addition to looking at the economics of physical barriers like row covers, we’ll be delivering enhanced trap-cropping strategies based on an understanding of what attracts beetles to cucurbits in the first place. Perimeter trap cropping relies on the preference beetles have for varieties with high levels of cucurbitacin, a compound that stimulates beetles to feed. Planting an attractive cultivar around the perimeter of a less attractive variety that we want to market concentrates beetle feeding on the perimeter, protecting the main crop. Early flowering is an added bonus for a perimeter crop, as beetles prefer to feed on flowers if they’re available, and we’re working to develop early-flowering varieties that maximize the attractiveness of the perimeter crop. We can also direct breeding in the main crop varieties to incorporate low beetle preference. We will precisely index varietal susceptibility to beetle damage, making it easy for you to select the right strategy for your farm.