Team:KU Leuven

The world population keeps on growing and since all people need to be fed while cultivable land is a limited resource, it is important to optimise crop yields. Different factors ranging from weather to diseases and pests have a huge impact on food supplies worldwide. An example of one of these factors are aphid pests. These can lead to yield losses worth more than a quarter billion US dollars!
Aphids leech on plants everywhere: ranging from crop fields to fruit trees and even in vegetable and flower gardens. Farmers try to control them by using insecticides, but these harm the environment and aphids can become resistant to them quite readily. This is why we, the KU Leuven iGEM 2013 team, created an ecological insecticide-free aphid controlling mechanism, which mimics natural signalling systems used by both plants and insects.

Our bacteria are called BanAphids and produce two pheromones. The first one is methyl salicylate, which plays a role in a plant’s defence response and is produced by the plant upon aphid infestation. The second pheromone is E-β-farnesene, which is an aphid alarm pheromone. In our system the BanAphids produce E-β-farnesene to repel aphids, while the methyl salicylate is meant to attract their natural predators such as ladybugs. In order to provide a proof of principle we contacted companies specialised in crop protection, Biobest and pc fruit, where we showed the functionality of these pheromones by performing insect experiments. Both companies were very interested and saw our project as a promising alternative solution.
We designed two systems of implementation for our BanAphids. In the first system, BanAphids are sprayed on the plants and in this case the production of pheromones is dependent on the presence of aphids. This system avoids the habituation of aphids to E-β-farnesene by only becoming active in the presence of aphids. The second system consists of a sticker containing BanAphids, that can be attached to a plant. This sticker system alternates the production of the pheromones by the use of our own designed oscillating system. This oscillator was extensively modelled by our team.

Since BanAphids will be introduced in the environment, the ethical aspect of our project cannot be underestimated. Therefore we developed a new additional approach: Bottom-up or ethics from within! In order to improve communication between different stakeholders and achieve reciprocal understanding in early stages of the project, we decided to develop a new additional approach from which the government, scientists, the public and even the industry can benefit.
This new approach is bottom-up structured where the dialogue between philosophers, scientists and the general public is central. And with the help of a unique collaboration between a philosophy student who joined the KU Leuven iGEM team and the general public, we have developed a new and strong framework for this approach.

We organised a symposium and a debate to inform the general public about our project and to open the discussion on the ethical aspects. We invited our neighbouring Benelux (Belgium, The Netherlands, Luxembourgh) iGEM teams for both events. Some teams participated this year so we are now considering a "Benelux-GEM slam" for the future. We also went out on the street and interviewed farmers to ask if they would use BanAphids and visited several schools with our own BioBricks and 3D-bacterium design to let students take their first steps in the fascinating world of synthetic biology.