Drosophila suzukii It is a pest that has been the talk of the town since 2017 with its first detections in Chile. Being a polyphagous pest with a great capacity to adapt to different climates, it has generated the need to analyze phytosanitary programs and become methodical with applications for successful control, especially in fruit trees with cycles as short as cherries, where any error that allows the females to lay eggs in the fruit can cost us dearly.
In order to identify key aspects in the control of Drosophila suzukii and to have important considerations for this season, we asked the Doctor in Agricultural Sciences, Master in Agricultural Sciences and Agricultural Engineer Karina Buzzetti for her opinion on the matter.
What was the balance of last season regarding the presence of Drosophila suzukii in cherry orchards? How can this affect us this season (we may start with more or less pest pressure)?
The current season is marked by an increase in favourable conditions for the development of Drosophila suzukii, due to the warm temperatures that coexist with high relative humidity. We have a lot of fruit with wounds due to the rains, which is also susceptible to attack by the pest. When this fruit falls, it serves as a reservoir for eggs, larvae and pupae, so the risk of increased attack on commercial fruit, including cherries, berries and grapes, is imminent.
In your opinion, what would be the critical moment of control?
In all commercial crops reported as hosts, the attack coincides with the break in color or appearance, and in the case of cherry trees, the first attempts at oviposition are reported from straw color onwards.
Do you recommend starting the season with the most effective tools, or stopping them once we have a higher proportion of soluble solids accumulated in the cherries? If you had to choose the key moment to use the most effective tool, what would it be? At the beginning, middle or end of the applications?
Once the attack begins, this pest does not give any respite, except in the northern part of the country, where the climatic conditions are not as favorable as in the central and southern areas. Therefore, highly efficient tools must be implemented throughout the strategy, and may be supported by other slower-acting tools such as entomopathogenic fungi, which are aimed at reducing population pressure in the medium case. As for effective and efficient tools, in my experience and recognizing the reports of international scientific literature such as the effectiveness rankings in the United States, some of the best valued products are the spinosyns Entrust, Success and Delegate.
For her part, Magalí Torés, Market Developer Cachapoal Norte of Corteva Agriscience, pointed out: “We developed the group of spinosyns, produced through the natural fermentation of a bacterium Saccharopolyspora spinosa. Qalcova™ (IA Spinosad, commercial name Success and Entrust), a mixture of spinosyns A and D with a control effect on thrips, moths and other insects by affecting their nervous system. Jemvelva™ (IA Espinetoram: commercial name Delegate), a chemical mixture of spinosyns J and L with a broad control effect on the orders Lepidoptera, Thysanoptera, Diptera and Coleoptera. The group of spinosyns has great selectivity towards beneficial insects, which allows for the creation of excellent integrated pest management programs.«.
What are the main attributes that an application program must have to achieve good control?
The key attributes of the spinosyn group are several: broad spectrum of insect control with improved insecticidal activity at the target site. Improved residual control with greater penetration through the cuticle. Greater stability to light, fast action that allows insect feeding to cease within a few minutes of exposure obtaining control between 1 to 24 hours post application. Rapid degradation which allows the environmental load to be reduced with a mode of action without cross resistance. Excellent alternative for Integrated Pest Management. Success, Enstrust and Delegate have excellent tolerances at destination and few days of local shortage that allow to put together a reliable and complete Drosophila suzukii control program.For more information, we invite you to visit www.corteva.cl , our social networks and contact our regional offices throughout Chile.
