Flower strips 2.0

Project responsible: Maria Viketoft, Deptartment of Ecology, SLU Uppsala.

Project group: Mattias Jonsson and Ola Lundin, Deptartment of Ecology, SLU Uppsala and Johan Stenberg and marco Tasin, Deptartment of Plant Protection Biology, SLU Alnarp.

Sowing nectar-rich flowers to support beneficial insects that consume pests is a promising plant protection method in Swedish horticulture. Strawberries are attacked by a number of pest insects where e.g. strawberry tortrix, weevils and thrips can cause extensive damage. The goal of this project is to provide better knowledge for designing effective flower strips for increased biological control of pest insects and increased pollination in organic strawberry cultivation without simultaneously aggravating problems with fungal diseases such as gray mold and plant-parasitic nematodes.

We do this by:

• 1) identifying which are the best flowering plants to support natural enemies and pollinators without favoring pests and diseases aboveground, and
• 2) identifying which are the best flowering plants to support a healthy soil without favoring plant-parasitic organisms.

25 different flowering plants will be sown in separate plots in a field trial to test their individual effect on beneficial insects, pollinators, pest insects and aboveground fungal diseases as well as soil organisms (nematodes and decomposition). The plant species that will be investigated in this field trial are determined in collaboration with extension officers. Based on these results, we will then

•  3) design optimal flower mixtures to maximize biological control of pest insects and pollination and evaluate them in organic strawberry cultivation.

The project starts 2021.