Biologische Bekämpfung des Kalifornischen Blütenthrips Frankliniella occidentalis unter besonderer Berücksichtigung des Einsatzes von entomopathogenen Nematoden

• Applicant: Professor Dr. Hans-Michael Poehling
• Subject Area: Plant Breeding and Plant Pathology
• Term: from 2002 to 2006
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5372964

Western Flower Thrips (WFT), Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), is one of the key pests in European greenhouses attacking a wide range of economically important crops such als vegetables and ornamentals. Due to its cryptic feeding behaviour and life strategy control of WFT is difficult. Entomopathogenic nematodes (EPNs) (Rhabditida: Steinernmatidae and Heterorhabditidae) are alredy found to be virulent aginst soil-dwelling development stages of WFT. However, different factors determine quality of EPNs for the control of insect pests. In the present study a broader screening for high virulent strains of EPNs is envisaged and abiotic and biotic constraints for EPN efficacy will be investigated in detail. These include the effect of types of growing media of the host plants, moisture content of the growing media, temperatures, and amount of irrigation water required to wash the nematodes down to the depth of pupation of WFT will be examined. Moreover, the effects of density and depth of pupation of WFT, time and frequency of EPNs application in respect to peak population levels of WFT, and persistence of EPN under semi-field conditions will also be investigated. Furthermore, the possibility of combining EPNs with other biocontrol agents of WFT, i.e. predatory mites (Amblyseius spp.) that feed on foliage-inhabiting WFT life-stages and the predatory mite Hypoaspis aculeifer that prey on soil-dwelling developmental stages of WFT will be investigated.

• DFG Programme: Research Grants
• Participating Person: Professor Dr. Christian Borgemeister