Abstract

The effects of transgenic, insect-resistant (Bt-) crops on biodiversity of non-target herbivorous insects and their natural enemies, and pollinators will be investigated. Four toxin/crop-combinations will be used for testing effects of insecticidal proteins from Bacillus thuringiensis expressed in the crop plants on associated insects, on different organisational levels. Both in the laboratory and in limited field experiments, effects of transgenes on the biodiversity of the associated insect community will be studied. The mode of action of Bt toxin in a beneficial insect will be studied in more detail. Molecular tools consisting of cDNA microarrays will be developed for fast and efficient observation of effects, based on changes in gene expression patterns. The project will deliver contributions to a solid scientific foundation for EU policies and regulations for release of transgenic crops, and tools for monitoring effects on biodiversity.

Objectives

• Determining the effects of Bacillus thuringiensis insecticidal proteins in trangenic crop plants on the biodiversity of associated non-target and beneficial insects (insect predators, parasitoids, and pollinators), at different organisational levels: cell, organism, and ecosystem
• Understanding the underlying mechanisms of observed effects on beneficial insects at the molecular level.
• Developing cDNA micoarrays as molecular tools for monitoring of Bt-transgene effects on insects.
• Contributing to a solid scientific base for the establishment of a European policy and of regulations concerning the release of transgenic, insect-resistant crop plants.

Description of the work

The workplan, consisting of 6 interconnected work packages, aims at studying Bt transgene effects at different organisational levels for four different Bt gene/crop-combinations . The work packages, all using these crops, involve laboratory studies on mode of action of the toxin and molecular tools for monitoring, laboratory feeding experiments, greenhouse and field cage experiments, and field sampling for determining biodiversity. Work package (WP) 1 will study the mode of action of Bt toxins on the important predatory insect green lacewing, on which an effect of transgenic Cry1Ab-corn, through a herbivore, has been described earlier. WP2 aims at developing cDNA microarrays as tools for monitoring adverse effects of plant-expressed toxins on beneficial insects, in this case lacewings. The utility of these microarrays will be tested with lacewings collected from Bt and non-Bt crop fields. WP3 will study effects of the 4 gene/crop-combinations on parasitoids of herbivorous insects in a tritrophic system. Effects on parasitoid behavior and fecundity and on behavior-mediating plant volatiles will be determined. WP4 will study effects of the Bt crops on pollinator behavior and biodiversity. Field sampling will be done to assess effects on pollinator biodiversity. Feeding studies on bumblebees will determine effects of transgenic pollen. Effects of transgenes on pollen and nectar composition will be determined. WP5 aims at determining, using laboratory feeding studies, effects of Bt transgenes on non-target herbivores and, through these herbivores, on insect predators such lacewings, ladybirds and spiders in a tritrophic system. WP6 involves field sampling of non-target herbivores and beneficial insects in field experiments with the four crops, comparing Bt- and non-Bt fields. Caged field plant experiments will study population dynamics of non-target herbivores and their prey in more detail.

Deliverables

• Knowledge on how non-target insect biodiversity might be affected by the use of Bt-crops.
• Identification of possible hazards from Bt-plants for biodiversity of non-target insects.
• Thorough evaluation of insect biodiversity in fields, as affected by Bt transgenes.
• Insight into the action of a Bt toxin on a beneficial insect and cues for ways to prevent negative effects.
• A tool to be used in monitoring effects of Bt transgenes in field insects.

Contacts

Coordinator

• Plant Research International Business unit Cell Cybernetics / NETHERLANDS

Participant

• Jozsef KISS / Department of Plant Protection HUNGARY
• Stefan VIDAL / Institut for Plant Pathology and Plant Protection Section Agricultural Entomology / GERMANY
• Salvatore ARPAIA / Metapontum Agrobios s.r.l. Laboratory of Agronomy / ITALY
• Peter EDWARDS / Swiss Federal Institute of Technology Geobotanical Institute / SWITZERLAND