Ganaspis kimorum wasp releases are an alternative to pesticides against Drosophila suzukii

02 Jul 2024
1043

After several years of laboratory studies, a research team from INRAE Sophia Antipolis recently released Ganaspis kimorum in the Vaucluse region to combat the Drosophila suzukii, a parasite causing severe damage to the cherry industry. These parasitoid wasps, natural enemies of the Asian fruit fly, offer an ecological alternative to pesticides. 

The Drosophila suzukii, native to Asia and identified in France in 2010, reproduces rapidly and lays eggs in fruit, making it unfit for consumption. This fly is a major scourge for tree growers, prompting the European Commission to ban the use of chemical treatments in 2022 for health reasons.

It is at the foot of Mont Ventoux, on the outskirts of the village of Malaucène, that a research team from INRAE at the Institut Sophia Agrobiotech started in early May to release Ganaspis kimorum. These tiny wasps, one millimeter long and native to Japan, lay eggs in D. suzukii larvae. During their development, G. kimorum larvae consume D. suzukii larvae, effectively and sustainably reducing the population.

After several years of laboratory experiments on G. kimorum at Sophia Antipolis, the parasitoid of D. suzukii in its native environment has proven to be a good candidate to control D. suzukii in an environmentally friendly manner.

Nicolas Borowiec, an engineer at INRAE specializing in biological control through acclimatization and project manager, emphasizes that "this parasitoid was selected because it effectively and specifically attacks D. suzukii in ripening fruits, thereby limiting undesirable effects."

In the presence of the senator of Vaucluse, the mayors of Malaucène and Venasque, Mylène Ogliastro, head of the Plant Health and Environment department at INRAE, and Frédéric Carlin, president of the INRAE Provence-Alpes-Côte d'Azur Center, researchers released 500 females of G. kimorum in the cherry orchards of Malaucène.

They will monitor this parasitoid introduction for several years to evaluate the effectiveness of this biocontrol strategy in controlling D. suzukii without the need for phytosanitary products. Additional releases of parasitoids are planned in southeastern France and other regions where the pest is present.

From Ganaspis cf. brasiliensis to Ganaspis kimorum

Results from numerous biological, ecological, and molecular characterization studies conducted in recent years unequivocally demonstrate the presence of several differentiated taxa under the same name "Ganaspis cf. brasiliensis". Within this complex, molecular group 1 (= G. cf. brasiliensis G1) is the most ecologically and physiologically specific to D. suzukii. This strain has been authorized for introduction into the environment in several countries (France, Italy, United States, Switzerland).

A recent publication by taxonomists specializing in Figitidae (the family to which the genus Ganaspis belongs) describes some of these groups as new species. This is the case of Ganaspis cf. brasiliensis G1, which thus becomes Ganaspis kimorum (Sosa-Calvo et al 2024). Journal of Hymenoptera Research. doi:10.3897/jhr.97.118567).

Source: INRAE
Image: INRAE


Cherry Times - All rights reserved

What to read next

How utilising wildflowers in the inter-row can improve pollination of crop under polytunnels

Tech management

16 Aug 2023

In 10 cherry orchards located in the West Midlands County (UK), wildflowers were cultivated in alleyways between rows of trees protected by polytunnels. The study involved the collection of data on the floral visitors of cherry and wildflowers over three years (2017-2019).

High temperatures in Japan, estimated -33% of volumes

Markets

04 Oct 2024

Officials stated that the estimated harvest of 8,700 tons for this season has decreased by 33% compared to the previous year and by 35% compared to the annual average. The annual harvest has fallen below 10,000 tons only once in the last decade: 9,160 tons in 2021.

In evidenza

Artificial intelligence improves cherry sorting: more quality and less waste

Post-harvest​

31 Mar 2025

Artificial intelligence is revolutionising cherry sorting, ensuring greater precision, reduced waste and higher quality. Find out how advanced technologies such as deep learning optimise packaging and improve productivity in the fruit and vegetable sector.

Successful Australian workshops on vigour management in the cherry tree

Press review

31 Mar 2025

Find out the results of workshops on cherry vigour management in Australia, with updates from Tasmania, Victoria, South Australia and NSW. International experts and innovations to optimise cultivation. Read more about winning techniques and strategies.

Tag Popolari