Maximizing Pollinator Protection and Natural Pest Suppression in Minnesota Fruit and Vegetable Crops

View the project final report

Commodities

• Agronomic: potatoes
• Additional Plants: native plants
• Animals: bees

Practices

• Crop Production: pollination, pollinator habitat, pollinator health
• Education and Training: extension, on-farm/ranch research
• Natural Resources/Environment: biodiversity, habitat enhancement
• Pest Management: biological control, integrated pest management
• Production Systems: agroecosystems, holistic management

Arthropod mediated ecosystem services (AMES) such as pollination and pest suppression are vitally important to agriculture, providing over $8 billion worth of services annually. Additionally, relying on natural enemies to reduce pest numbers or native bees for pollination instead of importing honeybees decreases pesticide use, and promotes more self sufficient and sustainable agricultural practices. Creating habitat for beneficial insects is an important tool for promoting AMES in agroecosystems. However, many studies have shown mixed results when habitat is provided, sometimes leading to increased pest pressure and other times reducing pest loads significantly. Additionally, little research has been conducted on how crop yields change when AMES are present. It is critical to understand the underlying community structure and interactions of the arthropods that habitat management promotes in order to determine what elements of these communities contribute to the desired ecosystem services and improve yields.

To address these issues and to improve pest suppression and pollination by beneficial insects, this project will: 1.Determine how habitat alters the community structure of arthropods

2. Identify which interactions and species are important directly or indirectly to achieving the desired AMES
3. Evaluate how yields change when beneficial insects are present

We will establish mixed vegetable crops adjacent to native prairie plots used to promote beneficial insects. We will conduct bioinventories of the arthropod community through bi-weekly vacuum and soil core sampling, and passive trapping. Pollinator transects will be conducted in the crops and the species and number of pollinators visiting crops will be recorded. PCR gut content analysis will be conducted on the natural enemies that are captured to determine which species are consumed by which predators. The crops will be harvested and the yields quantified. These data will be compiled to form quantitative food webs that contain species richness, diversity, evenness, and abundance, as well as the interaction strength and evenness present in the community. With these food webs and with the information gathered on crop yields, we can identify key distinctions between the communities, determine which interactions are the most influential and desirable, and begin to parse out which elements of natural enemy and pollinator communities are the most beneficial to providing useful ecosystem services.

Learning Outcomes

1. Increase grower knowledge of the benefits of insects and of providing habitat
   1. Determine which species of pollinators are most impactful
   2. Identify natural enemies that reduce pest numbers appreciably
   3. Determine how yields are influenced by the presence of habitat
2. Increase scientific knowledge of the changes habitat has on community structure
   1. Evaluate how species richness, and abundance change with habitat

1. Identify how evenness and species diversity change with habitat

3. Increase scientific knowledge of the interactions that influence ecosystem services.
   1. Determine which crop-pest interactions are most damaging and how this changes with the presence of habitat.
   2. Identify the strength of predator-prey interactions and which species target specific pests.
   3. Identify indirect interactions that influence productivity or salient direct interactions.

Action Outcomes

1. Provide growers with information on specific pollinators and natural enemies
2. Determine which natural enemies target which pests and to what degree
3. Identify pollinators that are the most beneficial to cucurbit crops
4. Evaluate how yields can be improved by providing habitat for beneficial insects
5. Create a series of comprehensive outreach presentations and materials to promote the creation of habitat and enhancement of beneficial insects by growers