Project

Climate and diversification effects on population structures and host selection behaviour of natural enemies

Olive fruit fly (OFF) is a major threat of olive trees causing high yield losses. Up to date, the control of this pest is mainly done by spraying synthetic pesticides. However, the OFF has developed resistance to pesticides limiting the effectiveness of this method. Long-term exposure to pesticides negatively affects humans’ health, the environment, and the quality of the olive products. Hence, an environmentally sound way of controlling this pest is of great importance. Therefore, to be able to develop an appropriate pest management it is essential to investigate the interactions between OFF and their parasitoids in different spatial and temporal scales and thus to understand how spatial heterogeneity and abiotic factors affect the ecological function of insect organisms in a given habitat. Knowledge on foraging behavior of OFF parasitoids and chemical cues involved in therein as well as on population structure and genetic diversity of the OFF and their parasitoids is essential to develop more adequate OFF control strategies and thus to minimize the negative impact of pesticides on the biodiversity in agro-ecosystems as well as on humans’ health.

Aim

The focus of this project is on the tri-trophic interactions between olive trees, OFF and their parasitoids in field and laboratory conditions. As such, I am intending to understand the behavioral and chemical mechanisms underlying on the tri-trophic interactions, as well as to investigate the migration patterns and reproductive behaviour of the OFF and the genetic structure of targeted parasitoids of the OFF as candidate biocontrol agents under specific local conditions. The main goal of this research is on how to modify the agro-ecosystem environment in order to increase the efficiency of the natural enemies of the OFF.

Approach

A survey on functional biodiversity is conducting in olive orchards in different geographic sites in the region of Messara, South Crete, Greece. The biodiversity status of the olive orchards before and after the establishment of the Green Infrastructure (GI) elements (e.g. various plant species in olive agro-ecosystem) will be assessed based on the effect of GI on OFF populations as well as on their parasitoids. For this purpose an extending sampling is in progress in the region. Furthermore, I am sampling OFF and their parasitoids to investigate the genetic diversity, population structure, and dispersion patterns of these populations to determine the migration patterns between different locations. The collected samples will be analyzed using mitochondrial DNA and microsatellite markers. The last part of my research will be consisted of behavioral tests (bioassays) and chemical analysis (plant volatiles) to investigate the chemical communication between different trophic levels.

Student Opportunities

We are open to applications for thesis projects! We have different thesis topics available, including projects with Field Work, Molecular Techniques and Plant Volitile Analysis.

  • Thesis projects
  • Are you interested? Contact Giannoula.Bogka@wur.nl