Historically, Vitaetom primarily dealt with Western Flower Thrips (Frankliniella occidentalis) in its pepper crops. However, recently Echinothrips americanus has become more prevalent, while this season the banded greenhouse thrips (Hercinothrips femoralis) caused the most significant damage.
Differing damage
Both Echinothrips and Hercinothrips are leaf-dwelling species, but the damage they cause differs. According to Crop Manager, Annelies Van Hauteghem: “Echinothrips pierce the leaf tissue, resulting in silver-grey discoloration, whereas Hercinothrips leave brown spots on the leaves and stems. In particular, damage from Hercinothrips can escalate quickly, rendering fruit unsellable.”
Valuable newcomers
These invasive thrips species were proving resistant to Vitaetom’s standard IPM strategy, says Annelies: “Initially we were relying on Orius-System and the predatory mite Degenerans-System. However, Orius primarily targets flower-dwelling thrips, and the mites are often too small to effectively combat the larger, leaf-dwelling species.”
In consultation with Biobest Crop Specialist, Sten Boonen, Vitaetom added two new products – Bug-Scan® Green and Vespiformis-System – to its control strategy.
The results proved promising. “Specifically, Echinothrips are strongly attracted to the green sticky traps, allowing us to monitor population size more accurately, detect new infestations early and respond promptly,” says Annelies. “For Hercinothrips, we use yellow sticky rolls.”
Successful introduction
In terms of predation, Vespiformis-System has become Vitaetom’s new ally. The predatory Franklinothrips vespiformis targets leaf-dwelling thrips right where they live. Annelies adds, “We observed good control of both Hercinothrips and Echinothrips. Interestingly, Vespiformis-System establishment was more successful in areas with a heavy Hercinothrips presence likely due to the fact it is less mobile than Echinothrips.”
Vespiformis-System is supplied as 1,000 adult predators in fully biodegradable packaging. Vitaetom introduced more than 20 units across 5,000 m². Initially released in Echinothrips and Hercinothrips hot spots, later on the predators were distributed across the crop. “With approximately eight individuals per square meter, we applied a relatively high dose,” says Annelies. “Given the intense Hercinothrips pressure, this was necessary – and it worked!”
Key component of IPM strategy
Annelies is pleased with the results achieved using Bug-Scan® Green and Vespiformis-System. “These products have proven to be valuable additions and are set to become a permanent part of our thrips control strategy.”
Sten Boonen is equally enthusiastic and is exploring ways to further improve Vespiformis-System performance, such as earlier predator introductions and providing supplementary feeding for the first generation. Steps that would ensure a strong Vespiformis population is in place before the first thrips appear, enabling even better control outcomes.
For more information on Vespiformis-System and Bug-Scan® Green, contact your Biobest advisor.
