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Exclusion nets against stink bugs
Given the higher presence of forest bugs along biodiversity elements (forest/hedge/flowers) edges, we suspect that certain plants/shrubs as a food source have an important impact on the development of local pest populations. With the aim to disrupt the migration to and from these food sources, we have installed exclusion nets over pear rows at several organic pear orchards of fruit growers taking part in the Operational Group ‘Biofruit debuggers’. These nets prevent adult forest bugs from flying back and forth between pear (side) rows and surrounding hedges/forests. By closing these nets in the right period (when the bugs become adults and looking for proteins), we prevent this important food intake and thus the production and ripening of eggs. The effect of the nets is evaluated through sampling of bugs and assessments of insect damage to the fruits.
Contact:
• Tim Belien, [email protected]
• Gertie Peusens, [email protected]
Partners: pcfruit vzw TWO Zoölogie, Biofruitadvies/Fruitconsult, and BioForum vakgroep biologisch fruit (Network of organic fruit growers) Funding: EIP Operational Group, Government of Flanders – EU (2017 - 2019)
More info: www.pcfruit.be
In both organic and integrated cultivation, monitoring of insects (pests and beneficials) is crucial. However, the current monitoring and warning system in Flemish fruit and vegetable cultivation is labor-intensive and often requires specific expertise for the identification of the various pest insects. The rapid progress in the areas of electronics, sensors, camera technology and artificial intelligence (image analysis/detection) offers perspectives for automation of the monitoring system. In this project we focus on the possibilities and development of automated observation and warning systems for 4 target cases: codling moth (Cydia pomonella),
Drosophila suzukii, lettuce root aphid (Pemphigus bursarius) and chicory miner fly (Napomyza cichorii).
Automatic identification on photos using camera-equipped traps
Great progress has already been made in the so-called camera-based automated monitoring systems. This is simply a common pheromone trap in which a camera is mounted above the glue plate. On a regular basis, the camera takes pictures of the glue plate, and these photos are stored via a wireless connection on a server (in the cloud). The photos can be consulted via a personal login at any time and from anywhere by the grower or advisor to see if and how many target insects have been caught. Moreover, for a number of target insects, an automated recognition has already been developed via image processing software. However, it is difficult to estimate how accurate, and therefore how reliable, this automatic recognition is. The practical validation of these systems is the subject of this automated monitoring project. We also want to make improvements such as the automatic replacement of glue plates and improved camera and smart detection technology. We also investigate the possibility of combining multiple attractants/pheromones in one trap, so that such camera-equipped traps can be used to monitor as many different pest insects as possible.
Automatic identification by measuring the wingbeat frequency
Another option for automated monitoring is the electronic identification of insects with the aid of an optical sensor. The principle of this detection technique is innovative, but actually surprisingly simple. When an insect flies between a light detector and a light source, the light intensity that falls
Automatic monitoring of insects
71 ‘shadow’ on the light detector, and with fully folded wings there is a minimal ‘shadow’. Typically an insect folds its wings in the order of magnitude of 100 to 600 times per second. The change in light intensity on the light detector will then have the same frequency as the beat (i.e. somewhere between 100 and 600 Hz). Because this wing frequency is characteristic of each type of insect, such a measurement signal results in a sort of unique ‘barcode’, which means that the insect can be identified automatically. In this project we also want to further develop this technique for the target case insects. Contact:
• Tim Belien, [email protected]
• Ammar Alhmedi, [email protected]
• Klaartje Bunkens, [email protected] • Bart De Ketelaere, [email protected] • Tania De Marez, [email protected]
Partners: pcfruit vzw TWO Zoölogie, KULeuven, Nationale Proeftuin voor witloof, Inagro
Funding: VLAIO LA-Programme (Agency for Innovation and
Entrepreneurship, Government of Flanders) (2017 - 2021), sector funding More info: www.pcfruit.be,
www.pcfruit.be/nl/geautomatiseerde-monitoring
The Asian fruit fly Drosophila suzukii or ‘Spotted Wing Drosophila’ has in a short time become the most damaging insect pest for both stone fruit (cherry), strawberries and woody small fruit (raspberries, blackberries and other berries) both in Europe as well as in the USA. In order to cope with this problem, the project “Knowledge-based practical solutions for the protection of Flemish fruit cultivation against Drosophila suzukii” (VLAIO LA- Programme IWT-LATR 135079 (2014 - 2018) was recently completed. This project has yielded knowledge and insights together with the investigation and testing of various practical control measures in the context of Flemish fruit growing conditions. The most promising control measures were obtained in the ‘Attract & Kill’ section, which included the discovery of the control potential of the European bird cherry (Prunus padus) as a so-called “dead-end host plant”. This project aims to further exploit the (ecological) ‘Attract & Kill’ control potential and to develop its practical application.
European bird cherry Prunus padus as natural enemy of D. suzukii
In laboratory studies, we were able to show that the fruits of European bird cherry P. padus are very attractive for egg laying of D. suzukii. In fact, when they have a choice between ripening sweet cherries and ripening European bird cherries, D. suzukii females show a significant preference to lay their eggs in the European bird cherry fruits. However, these fruits do not support development of the D. suzukii larvae. So it is a so-called “dead-end host plant”, which is very interesting to naturally suppress the
D. suzukii populations.
How to lure and how to kill?
With this project, we first want to find out which (volatile) components of
Prunus padus are responsible for the strong attraction of D. suzukii. We also aim to unravel the ‘killing mechanism’ in the ‘dead-end host’ fruits.