CropTec Innovation Day: An eye in the sky to tackle the arable farmer’s nemesis

By Laura Crook, Rothamsted Research

Blackgrass monitoring moves into a new era with remote sensing and artificial intelligence

Late last year blackgrass hit the headlines when a new study estimated that herbicide resistant strains of the weed are costing the UK economy nearly £400 million annually. That’s equivalent to 800,000 tonnes of lost harvest each year, with potential implications for national food security.

Using modelling carried out by international conservation charity ZSL (Zoological Society of London) based on resistance assay research undertaken by Rothamsted Research, a worst-case scenario – where all fields have a high proportion of resistant blackgrass – estimated an annual cost to farmers of £1 billion, with a wheat yield loss of 3.4 million tonnes per year.

The study emerged from the Black-Grass Resistance Initiative (BGRI), a four-year collaborative project funded by the Biotechnology and Biological Sciences Research Council (BBSRC) and the Agriculture and Horticulture Development Board (AHDB). This has involved scientists from ZSL and Rothamsted together with Newcastle, Sheffield, York and Edinburgh Universities. The aim was to take a gene-to-landscape approach towards investigating the causes of herbicide resistance in blackgrass. The ZSL led paper was just one of a number of important studies that are now being published.

At Rothamsted I worked as a technician on the project, focussing on testing the herbicide resistance status of various blackgrass populations. We started in the summer of 2014 by visiting winter wheat fields in the main areas of the country affected by the problem, from Oxfordshire across to Norfolk, Bedfordshire to Yorkshire, and collected seed from these fields. We then spent the next year testing all of these populations with three different herbicides to get a picture of the level of resistance within the UK. Our results have shown that 79% of our populations were resistant to all three of the herbicides we tested. This preliminary work was vital for then focussing our subsequent glasshouse experiments on researching the genes underpinning resistance in blackgrass.

Meanwhile, the team at Sheffield University have spent the past few summers visiting the fields to map the density of blackgrass. This involves walking the tramlines and recording the density on a 5- point scale; absent, low, medium, high and very high. These results are then turned into distribution maps showing the patches of blackgrass across fields and providing a means to compare densities across years. These maps were sent to the farmers to help inform their blackgrass management.

A novel aspect to the BGRI has been that for all the fields surveyed by Sheffield and Rothamsted, we have collected historical management data going back as far as ten years and including cultivations, crop rotation, and herbicide applications. We have then used this information to develop models to determine if certain management strategies are leading to an increase or decrease in the blackgrass problem.

Other useful outputs included a diagnostic kit developed by Newcastle University, which tests blackgrass plants for non-target-site herbicide resistance. This lateral-flow device works in a similar way to a pregnancy test kit, with a diagnostic band indicating a positive result (herbicide resistance) that can provide a farmer or agronomist with information for the coming growing season. This test is faster than previous methods which involve collecting seed for testing which can only provide a retrospective answer.

The BGRI has also created a fantastic network of over 60 farms which has become a valuable long-term resource for investigating blackgrass management.

The most recent development emerging from the project has been the launch of aiScope: A surveillance programme to catch the early signs of developing resistance. With our partners at Sheffield University, we teamed up with Hummingbird technologies, Precision Decisions Ltd and IBM research UK to systematically monitor blackgrass across England.

By flying drones over farmers’ fields, we’ll be able to more rapidly survey infestations of the pernicious weed, and through our partnership with IBM, we will leverage cutting edge ‘artificial intelligence’ computing. It’s hoped that this type of monitoring will help us to hone-in on the techniques which can still work to control blackgrass in the field.

Over the next few seasons, working with our new project partners, we will continue to improve our monitoring and understanding of blackgrass, with the hope that one day we’ll be able to say that its days as the preeminent arable weed are numbered.

CropTec Innovation Days

Want to find out more about black-grass monitoring, integrated weed management and sustainable weed control? Laura Crook will be joining us at the Weed Innovation Workshop, brought to you by CropTec Show and Rothamsted Research, to speak about Croprotect – what can it do for you? You’ll also have the opportunity to see the Rothamsted field trials for yourself and ask questions!

Find out more about the Innovation Day here