Field Suppression of Spotted Wing Drosophila (SWD) (Drosophila suzukii Matsumura) Using the Sterile Insect Technique (SIT)

/in ,

Field Suppression of Spotted Wing Drosophila (SWD) (Drosophila suzukii Matsumura) Using the Sterile Insect Technique (SIT)

Tags: , ,
R. A. Homem, Z. Mateos-Fierro, R. Jones, D. Gilbert, A. R. McKemey, G. Slade and M. T. Fountain,  Insects,  13. 2022.

Drosophila suzukii (spotted wing drosophila;SWD) is an economically important pest of soft and stone fruit worldwide. Control relies on broad-spectrum insecticides, which are neither fully effective nor environmentally sustainable. The sterile insect technique (SIT) is a proven, effective and environmentally friendly pest-management tool. Here, we investigated, for the first time, the potential of using SIT to control D. suzukii in field conditions without physical barriers that limit insect invasion. A proprietary method of rearing and irradiation with X-rays was used to obtain males that were 99% sterile. Sterile males were released twice per week from April to October 2021 on a site in Kent, UK, where everbearing strawberries were grown in open polytunnels. The infestation of wild female D. suzukii was monitored weekly using red sticky traps with dry lure at the treated site and at two similar control sites that did not receive sterile male releases. Releases of sterile males suppressed the wild female D. suzukii population by up to 91% in comparison with the control sites. We thus demonstrated the feasibility of SIT to achieve season-long control of D. suzukii using early, sustained and dynamically targeted releases of sterile males. This provides a promising environmentally friendly method to control this important pest.

Mean numbers of female D. suzukii (±SE) captured per trap and per week at the SIT-treated and untreated control sites throughout the trial. Statistically significant differences (p ≤ 0.05; GLM mixed model) between the SIT-treated site (yellow line, n = 31) and each of the untreated control sites 1 (blue line, n = 6) and 2 (orange line, n = 6) are represented by an asterisk above the error bars for each week. Foliar insecticide application (cyantraniliprole (100 g L−1) at a rate of 750 mL ha−1 the SIT-treated and untreated control sites are highlighted by vertical grey dashed lines.

Image from: Homem et al 2022–10.3390/insects13040328