The system involves the observation of insects in the laboratory under standardised conditions. They are given the choice of two leaves and are monitored to see which route they take to the leaf and how long they spend on it feeding or walking. These data are then analysed by software to create an objective measure of the relative resistance of a given plant against the tested insect.
Resistance analysis
“This new method allows us to test very quickly a large number of plants for resistance to pests such as sap-sucking insects,” Jongsma explains. “The novelty is that we are watching the actual behaviour of the insects, so we don’t have to wait for visible damage to the plant or monitor the reproduction of the particular insect. We are instead observing the earliest signal you can pick up. We know which plants are less attractive to pests within just a few hours.”
Objective and quick
For this study, Jongsma has teamed up with phytopathologist Bas Brandwagt from Royal Van Zanten . “I see great advantages to this system,” Brandwagt says. “First of all, it allows us to collect objective data rather than subjective visual observations, which leads to a lower risk of error. Furthermore, we can screen large numbers of samples of different genotypes very swiftly. Of course, observing an insect on a small piece of a leaf is not the same as studying it on an entire plant. However, this innovation is potentially a great support as a pre-screening method for breeding for resistance to given insects.”
On the market in three years
The system is currently being developed further in cooperation with Noldus Information Technology as well as Royal van Zanten and another three breeders of vegetables and flowers. “It is our goal to make the method suitable for many specific insect-plant combinations,” Jongsma continues. “The current focus is on thrips, aphids and whiteflies. There are possibilities, however, to develop protocols for other insect-plant combinations, now as well. The plan is to have a concrete product on the market within three years.”
