BigSis trials indicate chemical-free path for SWD control

By Michael Barker

UK trials of a biological and chemical-free technique for the control of spotted wing drosophila (SWD) in soft-fruit crops have shown how it can outperform insecticides when used in commercial conditions, according to the manufacturer.

Developed by British start-up BigSis, the system, which uses an updated version of the sterile insect technique (SIT), reportedly reduced numbers of the damaging adult female SWD by up to 88 per cent compared to a conventional, sprayed control.

Funded by an international company that has been working with BigSis to validate the chemical-free solution for global use, the trials also achieved an 80 per cent reduction in signs of SWD activity on the fruit and saw fruit waste during picking cut by more than half.

″Only two years ago we completed a world-first field trial of an SWD control solution based on SIT with results that showed up to 91 per cent reduction of female SWD numbers in commercial strawberries,″ said BigSis founder Glen Slade.

″To achieve such good levels of control this year, again on a commercial farm, but this time compared to industry standard insecticide use, is a vindication of SIT’s ability to provide growers with a non-chemical, non-GMO, non-toxic route to effective and affordable insect pest control.″

UK raspberry trials

The UK trials focused on an 11ha field of Maravilha raspberries divided into three maturities, a common practice that allows continuous harvesting from early July to early September.

In each maturity, BigSis SIT was compared to control plots that received a single spray of Tracer (spinosad), the company explained. Insect traps recorded adult female numbers in each plot. The fruit waste during picking was monitored across all plots and marketable fruit were inspected for signs of SWD activity.

First deployed more than 60 years ago, SIT – which uses sterile male insects to arrest the growth of an in-crop pest population – had always been regarded as too expensive to deploy commercially, BigSis noted.

The BigSis approach combines artificial intelligence and robotics to raise, sort and sterilise millions of male insects in an automated production facility, with the company claiming it has effectively reinvented SIT and slashed its cost by up to 90 per cent, making it affordable for field-by-field control.

BigSis launched its season-long insect control as a service (ICaaS) in 2023, offering growers on-farm releases of its sterile male insects.

″We’re delighted with the results, as is the company that funded the trial,″ said Slade. ″Our SIT is a zero-regulatory approach for many of the key markets in soft-fruit production, including England and four leading states in the USA.

″Effective control of SWD addresses a major global need in high-value crops, while enabling farmers to meet the expectations of regulators and consumers by reducing the use of crop protection chemicals in food crops.″