College of Agriculture & Natural Resources Department of Entomology

Two 2023 studies with significant contributions from Michigan State University Entomology researchers have recently been recognized as some of the most read and cited articles in the Environmental Entomology journal, published by the Entomological Society of America. 

These studies, one focusing on the foraging behaviors of managed honey bees and bumblebees, and the other on the pupation of the Corn Earworm, provide critical insights that can shape future agricultural practices. Both studies, recognized as some of the most read and cited articles in Environmental Entomology, emphasize the significance of ecological knowledge in developing sustainable agricultural solutions. By applying these findings, farmers can enhance productivity while supporting environmental sustainability, contributing to the long-term health of both crops and ecosystems.

Identity and diversity of pollens collected by two managed bee species while in blueberry fields for pollination

The first study, led by Rufus Isaacs’ lab, investigated the pollen foraging behaviors of two managed bee species—Honey Bees (Apis mellifera) and Bumblebees (Bombus impatiens)—within highbush blueberry fields. 

Graham et. al. (2023) explored how pollinators play a pivotal role in crop reproduction, yet their foraging behaviors can be influenced by several factors, including their natural instincts and nutritional needs. Understanding how different bee species impact pollination is not only essential for optimizing agricultural productivity, but also because it could be crucial for addressing bee population declines, which threatens the biodiversity of Earth’s ecosystems. 

The researchers collected and analyzed pollen samples from both honey bee and bumble bee colonies over the course of two years at 14 highbush blueberry farms in southwest Michigan. The study found that bumble bees, compared to honey bees, foraged from a wider diversity of plants. This behavior is likely because honey bees tend to focus on abundant, high-quality resources, which they communicate to the entire colony, whereas bumble bees are more solitary and opportunistic, selecting foraging sites based on their colony’s nutritional needs. Interestingly, highbush blueberries were the dominant crop in these study areas, yet the pollen from this crop represented less than 27% of what bumble bees collected and less than 6% of what honey bees gathered. This finding suggests that the low protein content of blueberries may cause bees to seek alternative crops to meet their nutritional needs.

This research highlights the importance of considering the diverse foraging behaviors of these bee species when designing agricultural landscapes. By planting a wider variety of crops, farmers can cater to the bees' nutritional needs and improve crop pollination, leading to better yields.

Moisture and soil type are primary drivers of Helicoverpa zea (Lepidoptera: Noctuidae) pupation

The second study was conducted by the Department of Entomology and Plant Pathology at North Carolina State University with significant contributions from Michigan State University entomologists, DeShae Dillard and Hannah Burrack.

 Dillard et. al. (2023) explored the variables driving Corn Earworm pupation (the process in which insect larva transform into a pupa; the stage between larvae and adult) by comparing pupation within undersaturated and saturated conditions across three distinct soil types– coarse sand, organic muck, and fine-textured clay.

Corn Earworm (CEW) is a devastating, migratory pest in crops such as sweet corn, tomatoes, cotton, soybeans, and tobacco. CEW larvae feed on crops and have potential to damage crops significantly. This study, focusing on the interaction between soil moisture and type on pupal depth, weight, and adult emergence, offers valuable insights into the ecological preferences of CEW.

The research found that soil moisture is a primary factor influencing pupal depth, with shallower pupal depths occurring in moist soil. Additionally, the study revealed that soil type also impacts adult emergence. Fine-textured clay, especially when dry, is more compact, making it harder for adults to emerge, whereas coarse sand and organic muck provides less resistance, making adult emergence easier. This is important because it could be helpful when developing more effective pest management methods. By adjusting the timing and methods of pest control based on these findings, farmers can minimize crop damage and reduce environmental impact.