Carrot growers review trials of linuron alternatives

Following the withdrawal of herbicide linuron, growers attended an AHDB field trial to find alternative means to protect carrot crops against invasive weeds including fat-hen, fiddleneck, and knotgrass.

Plant disease experts and growers gathered in Yorkshire to review treatments currently being trialled on carrot and parsnip crops, including new actives and novel tank-mixes – some of which already appear promising.

The trials form part of SCEPTREplus, AHDB’s £1.4 million research program, which focusses on developing sustainable solutions for growers across the country.

“With the loss of linuron, the future of weed control looked uncertain. However, the trials here are already looking very promising and show that there are alternative options, which may be available soon,” said Joe Martin, AHDB Crop Protection Senior Scientist.

“We are generating valuable data to aid decisions on taking products forward for approval for use on farms, developing knowledge that can be applied to keep the horticulture industry productive in the future. AHDB will continue to be at the forefront of investigating alternatives in the face of further changes to regulation.”

Several products were selected for inclusion in the trial, for their ability to target weeds identified by a panel of industry experts as being problematic. These weeds were groundsel, mayweed, fools parsley, bindweed, cranesbill and polyganums.

As part of the event, visitors were able to view the plots and see the results for themselves.

Commenting on the findings so far, ADAS Plant Pathology Consultant Emily Lawrence, said: “In total, we’re working with a number of products which are being tested at different application timings, either alone or in tank mixes with currently approved products.

“The trials have built upon previous years’ work and there are four being carried out on carrots and five on parsnip’s in 2019. At this stage, we’re seeing promising results with a post-emergence application of aclonifen, which we are working on to get approval. However, I wouldn’t say it’s at a point where it’s a direct replacement for linuron”

For more information on the SCEPTREplus programme and its research on high priority disease, pest and weed problems please go to the following https://horticulture.ahdb.org.uk/sceptreplus