3 key Rothamsted research areas and how farmers will benefit
© AdobeStock/megaflopp A strong link between research and practice has never been more vital.
We talk to leading researchers and independent crop consultants to see how science at the world’s oldest research centre will help arable farmers tackle their biggest challenges.
See also: How West Midlands farm is planning regen approach on 1,600ha
1. IPM research provides hope for sustainable OSR
Research on how best to deploy integrated pest management (IPM) techniques in oilseed rape is giving one Hampshire-based adviser hope it can be a sustainable part of rotations once again.
The Europe-wide EcoStack project is aiming to develop ecologically, economically, and socially sustainable crop production strategies for farmers, and as part of the project, Rothamsted’s Sam Cook’s is fine-tuning IPM advice in OSR.
Flower margins
She is investigating the role of flower margins or strips in pest control and pollination, including optimising the placement and plant species mixtures within these areas to attract the right insect species.
Dr Cook and her team have planted a range of wildflower species in and around oilseed rape plots, then using visual assessments and vacuum sampling have studied what insects are present.
“We know the more biodiversity we have, the more insects you find. It’s just about getting the mix right to deliver the insects that will do the best job for the crop and that’s what we hope to achieve,” she explains.
Cabbage stem flea beetle
These insects could include pollinators such as bees or hoverflies, and parasitic wasps, which are known to parasitise and eventually kill cabbage stem flea beetle (CSFB) adults as they become active in late summer.
Other collaborative work between The John Innes Centre (JIC) and Rothamsted has also been trying to tease out differences in palatability of oilseed rape and related species to produce varieties less attractive to CSFB.
Hampshire-based Richard Cromie says it represented about 25-30% of rotations across his south-coast patch a decade ago, but has declined dramatically since use of neonicotinoid insecticide seed treatments ceased.
As management of the pest had been easy for a long time, less was understood about its lifecycle and what draws it into oilseed rape crops.
Along with the outcomes of the research project outlined above, which will boost predation of the pest and provide more tolerant varieties, Mr Cromie believes a better understanding of its lifecycle will be important, too.
“I have my suspicions from observations in the field during peak migration and the worst-case scenario seems to be oilseed rape seedlings on bare soil.
“I’ve seen it on farms where we’ve ploughed and min-tilled cover crops in side by side, then drilled over the top. Where ploughed, there is three times the damage,” he explains.
He hypothesises that it might be linked with carbon dioxide release from the cultivated soil that attracts the adult beetles, or volatile compounds released by oilseed rape seedlings, or a combination of the two.
Establishment strategies
This is leading to Mr Cromie to tweak establishment strategies, with cultivation kept to a bare minimum, unless a low-disturbance subsoiler is needed to correct any soil compaction that might impede rooting.
Many choose to go early and get the crop to the 2-4-leaf stage before beetles move in, while others choose to go later, once the migration has finished.
Mr Cromie favours later drilling, as clubroot likes soil temperatures of 16C or more and he sees more of the disease when drilling early, particularly in charlock infested fields.
“Being on the south coast, winters set in later in most years, so as long as soil conditions are good, we drill vigorous hybrid varieties from around the 10 September.
“Working in chicken muck or digestate works better than straight diammonium phosphate starter fertiliser in getting the crop away, which could be down to the ammonia masking whatever attracts them in, as well as the nutrition.
“We also tend to leave volunteer cereals as long as possible to give the pest something to think about,” he adds.
2. Understanding soils to improve crop performance
Putting quantitative data on what constitutes good soil management is a key aim of ongoing Rothamsted work, and one Association of Independent Crop Consultants adviser hopes it will instil confidence in the systems changes needed on farms.
Crop management techniques
Rothamsted is currently testing a sensor system to understand how greenhouse gases (GHG) – with a focus on carbon dioxide and nitrous oxide – are affected by changes in soil structure.
A vast underground network of fibreoptic cables and sensors is constantly measuring temperature, moisture, and gas fluxes throughout the profile.
Researchers are collecting data on a weekly basis and can see how these metrics interact with different management practices, such as establishment method and crop rotation.
The aim is to find out how best to manage agricultural soils to minimise GHG release and mitigate climate change, with healthy, biologically active, well-structured soils releasing less carbon dioxide.
Bacteria
Alongside the impact of structure on emissions, different management strategies are being assessed for impact on soil biodiversity and, more specifically, bacteria.
It is hoped this will allow growers to use these micro-organisms to improve crop performance by controlling soil-borne pathogens or improving nutrient uptake by plants, for example.
Rothamsted molecular microbiologist Ian Clark says data is building on certain endophytes and their benefits, and some are already offered to farmers as seed treatment products.
“One of the main challenges is that they need to compete well in the soil environment after application, so using bacteria isolated from your own soil could be important. These are the details we are trying to establish,” he explains.
Indigro adviser David Boulton is encouraged by the potential of microbes, but urges caution until more independent work – like that being carried out at Rothamsted – gives some more solid answers.
“If you don’t get the basics of good rotation, soil structure, and improved organic matter levels to create the right ecosystem, no matter what biological product you apply, it will provide little benefit to the soil or crop.
“If you are interested in applying microbes, get your soil in a healthy state first and then look at artificially introducing species,” he adds.
Mr Boulton sees Rothamsted’s soil organic carbon-clay index, designed to provide a simple method to normalise soil organic carbon values across soils, target remedial action and assess changes in status over time, as a helpful tool in making these improvements.
Cultivation
The research into gas emission is also important, says Mr Boulton, particularly as growers are changing cultivation systems.
It shows that minimal disturbance or no-till can reduce carbon losses, but it has the potential to create conditions that increase nitrous oxide emissions – a GHG 300 times more powerful than carbon dioxide.
“If you do the wrong operations at the wrong time, compacting the soil, then that soil becomes anaerobic, and you end up polluting in a different way to ploughing.”
To ensure this doesn’t happen, he says visual examination of soil structure tests to assess soil structure after harvest will help identify horizontal layers of compaction and ensure crop establishment plans include targeted use of a low-disturbance subsoiler to break it up.
“At the other end of the spectrum, if you’ve grazed livestock ahead of an arable crop and the compaction is close to the surface, use shallow discs or tines break it up and reduce the potential for nitrogen dioxide emissions.
“Drainage maintenance is key, including ditch clearance, and utilising cover crops and organic amendments will also help improve soil structure and reduce the risk of anaerobic conditions,” says Mr Boulton.
He adds that he is encouraged by Rothamsted putting some metrics and quantitative data on soil management practices that have been abandoned over recent generations as synthetic inputs increasingly propped up yields.
“It’s important that basic knowledge and understanding of soils is improved so we adopt the correct techniques that will lift performance on farm and meet other challenges, such as climate change.”
‘Holy Grail’ of wheat varieties closer than ever
Andrew Blazey, Association of Independent Crop Consultants chairman-elect and Essex-based agronomist with Prime Agriculture, thinks UK consumers, growers and the environment will soon be benefiting from the advances in plant breeding championed at Rothamsted Research.
Much of the discussion regarding the latest breeding technology surrounds gene editing (GE), which uses CRISPR-Cas9 – essentially a molecular pair of scissors – to make changes to an organism’s genome and express desired traits.
Along with GE, older genetic modification (GM) technology – a process that transfers a piece of DNA from one organism into another – still has an important role to play, too.
Rothamsted’s Sarah Raffan is working on a GE project at Rothamsted that uses CRISPR-Cas9 to knock out the TaASN2 gene linked to the production of free asparagine and reducing sugars in wheat.
These substances naturally occur in crops such as wheat and potatoes, and when cooked in certain ways they produce acrylamide, which is a known carcinogen.
The team at Rothamsted has produced GE Cadenza wheat that yields grain with 70-90% lower asparagine levels than non-GE Cadenza and is being grown in field trials for the first time this year.
If GE low-acrylamide wheat is commercialised, it could help to significantly reduce consumption levels, making favourite foods such as toast and breakfast cereals much safer to eat.
However, Mr Blazey says he would like to see the technology used to help the producer as much as the consumer, perhaps for “Holy Grail” wheat varieties with good disease resistance, drought tolerance, the right quality characteristics and better nitrogen use efficiency.
At present, growers in the east of England struggle to find a market-accepted milling wheat that fulfils their needs, with Skyfall and Zyatt very susceptible to yellow rust and Crusoe susceptible to brown rust.
Orange wheat blossom midge and barley yellow dwarf virus tolerance are also lacking in Group 1s, so using technology such as GE and GM could quickly bring these traits forward.
Researchers and agronomists working together
Rothamsted Research is one of the world’s oldest agricultural research institutes and its director and chief executive, Angela Karp, recently hosted 50 Association of Independent Crop Consultants (AICC) members at its main site in Harpenden.
It is hoped that strengthening ties with organisations such as the AICC will see new knowledge cascade down to growers and solve some of their most pressing challenges quicker than ever before.
She says that engaging with agronomists and farmers is critical for researchers in agricultural sciences, as they are essentially “customers” who ultimately implement and benefit from the outcomes of past, current, and future projects.
“For our part, we need to make sure that our research addresses the realities faced by practitioners on the ground and helps solves immediate problems as well as future ones.
“Likewise, we hope that by discussing our findings openly – and having them robustly challenged – we can help AICC members, and their clients, keep abreast of important discoveries and promising new lines of inquiry.”
Sarah Cowlrick, AICC’s chief executive officer and organiser of the event, says this two-way process is valuable for both sides, with members telling researchers about their challenges and taking away new findings that will help their clients back home.
