A standing army in the field?! How effective is augmentative biocontrol using banker systems in suppressing pest populations in open field vegetables?

Banker plants are often used in protected cultivation to support the released biocontrol agents (BCAs) with alternative (supplementary) resources such as flowers or alternative prey. Banker systems may thus ensure that a “standing army” of beneficials is present even in times when the pest is scarce or absent. Providing supplementary resources together with banker plants and releasing BCAs seems like an effective strategy to improve the biological control of pests also in open field crops. Especially in impoverished agricultural landscapes, where naturally occurring beneficials are scarce, the release of BCAs on banker plants may ensure that natural enemies are there on time and in high enough numbers to prevent pest situations.

This proposition, however, is not trivial because of the various species interactions that may take place in the field. The supplementary resources may attract an entire entomofauna in the open field that may or may not interact with the target BCA. For example, the supplementary resources may not only facilitate the target BCA but also antagonists or competitors, hindering BCA establishment or dispersal into the neighboring crop. The banker plants might attract species that are preferred by the BCA over the target pest, which may also prevent BCA dispersal into the neighboring crop. Alternatively, bankers may attract other beneficials that will facilitate the impact of BCAs without interacting with them. The interactions between the BCAs, the banker system, and the alternative resources and the natural entomofauna will determine if pest suppression in the neighboring crops are strengthened or weakened. We study these interactions using field experiments.

In this project we will establish and compare several types of banker plant – BCA systems and explore how they interact with the target pest and the resident insect community in the field. Besides the ecological questions, we want to answer more applied questions, such as “Is it better to deploy a single banker-BCA combination or is it better to use several banker-BCA combinations? What are the practical considerations from the grower’s perspective?

Do you find any of these questions interesting and are you fascinated by learning about insect ecology, agroecology, and ecosystem services? Do you have a hands-on attitude towards research and like to participate in field research? If your answer is yes to these questions, then feel free to send an email and join our team for your internship!

Internship: begin June to end September 2024
Location of experiments: Wageningen
Contact: Tibor Bukovinszki, PhD
Email: tibor.bukovinszki@wur.nl
Wageningen University & Research
Field Crops / Open teelten