Harrogate: This was the subject of a seminar organised by the Farmer-Scientist Network of the Yorkshire Agricultural Society at the Great Yorkshire Show today.
Dr Roma Gwynn of Biorationale said that there was no precise definition of biocontrol, but it was about substances based in nature, There was a global annual growth rate of 20 per cent in biopesticides compared with five per cent for chemicals. 30 per cent of active substances registered in the EU were now biocontrol and 50 per cent of those coming through. They were extensively used in horticulture, but there was considerable scope in arable.
Professor Rob Edwards of Newcastle University said that diagnostics helped us to decide where we should and should not use chemicals. A spring wheat trial had been carried out in 2017 and a winter wheat trial on three sites in 2018 to see what worked with different resistance and different treatments. We were going to have to wean ourselves off pesticides. Roma Gwynn said that we should make those we do have last as long as possible.
No difference had been found between treatment regimes and varieties, but there was more protein in biocontrol treated plants. The objective was to enable plants could better access nutrients by placing microorganisms around the root. A more plant centric approach was needed.
It would be 10 to 15 years after Brexit before any distinctive UK legislation would be possible. The project was the beginning of a much longer story.
Rob Edwards said that we had to move from fixing things that were broken to stop them happening in the first place. We were using old fashioned testing criteria for new varieties.
Dr Gwynn said that the project had the potential to drive the conversation, to take evidence to government.
Rob Edwards showed a kit which gives an idea of how strong the resistance trait was. One was managing blackgrass rather than total eradication which was not feasible.
In discussion the importance of healthy soil was emphasised. There were benefits from growing crops together, a polyculture type of production. The challenge was to match that up with modern machinery. Growing clover as a cover crop benefitted the soil, nitrogen input was reduced. Monoculture was a perfect system to encourage pests and disease.
Biocontrol is variable, affected by the weather, not as consistent as conventional chemistry. There was a need to do a lot of things together [implying more demanding management and a higher level of skill].
Work was needed on public perceptions of biopesticides. There were a lot of preconceptions in the public and a need to understand what these were. People would happily buy biocides, but once technology went into food, perceptions changed easily.
A farmer questioned the compartmentalised terminology which was not helpful. What was conventional agriculture?
Rob Edwards noted that alternative UK technologies were used extensively in sub Saharan Africa. Roma Gywnn observed that Kenya had established biocontrol and integrated pest management before Europe had moved. The Kenyan Government had listened and changed regulation.