Small farmers invest significant time and resources to prepare for harvest, but pests such as striped and spotted cucumber beetles can cause serious crop losses. These beetles damage cucurbit crops, including cucumbers, squash, pumpkins, and melons, making them a major concern for farmers.
Research led by Dr. Suzanne Blatt, a Research Entomologist at Agriculture and Agri-Food Canada (AAFC), is focused on developing sustainable solutions to manage these pests. Since 2020, her team at the Kentville Research and Development Centre has worked with partners to explore new pest control strategies.
Striped cucumber beetles and spotted cucumber beetles are small yellow insects commonly found in Nova Scotia. They overwinter as adults near farm fields and become active in late spring or early summer. As climate conditions change, these pests are appearing earlier in the growing season, increasing risks for farmers.
"Home gardeners and commercial growers alike can lose their squash and zucchini plants to these beetles. For the home gardener, it’s the loss of their home-grown fresh vegetables, but for the commercial grower, it’s the loss of income. Both beetles thrive in Nova Scotia, and ‘a few beetles’ can quickly become ‘a few thousand beetles’ in a squash planting," said Dr. Suzanne Blatt.
Both adult beetles and larvae damage plants. Adults feed on leaves and flowers, while larvae attack roots in the soil. This weakens plant growth and can prevent crop production entirely. In addition, these beetles spread bacterial wilts, a disease that damages plants and reduces yields by affecting their ability to function properly.
Dr. Blatt’s early research tested a “push-pull” strategy using trap crops and companion plants. Baby Blue Hubbard squash was planted to attract beetles, while nasturtiums were used to repel them. Results showed some success when beetle numbers were low. However, under high pest pressure, the method was less effective.
The study also found that butternut squash is less attractive to these pests, and that companion plants can influence egg-laying behavior of other insects. These findings are helping guide future research directions.
The next phase focuses on improving trap cropping by adding entomopathogenic nematodes. These microscopic organisms attack pests in the soil and could reduce beetle populations. Applying them only to trap crops may lower costs, reduce pesticide use, and decrease fuel consumption by limiting field operations.