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Opinion

Forward - Introduction from this issue’s sponsor.

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Last Word - A view from the field from CPM’s technical editor

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Significant step at a critical time

Neil Kay is BASF Agricultural Solutionsbusiness director for UK and Ireland

As a company, our mantra at BASF is to dothe right thing, not the easy thing and thissentiment certainly applies to the discoveryof Revysol.

It’s been 15 years since the last azole waslaunched, and it feels like the regulatory environment is stacked against us for achievinga new authorisation for this class of chemistry. It is fantastic to achieve the registration ofRevysol in the UK, because to do this we had to completely rethink our approach to its development. The launch of Revystar XE bringsto the market the first isopropanol-azole combined with Xemium, the best in-class SDHI.I sense that the industry is collectively giving a

huge collective sigh of relief at this very positivenews. The authorisation comes at a critical timegiven the loss of chlorothalonil and an ever-challenging disease control environment.

As a wider business, we have an exceptionally strong pipeline of crop protectionproducts, including a blackgrass herbicide, arange of pioneering digital solutions and a comprehensive seed portfolio, including ahybrid wheat breeding programme.

We continue to work closely with growers, aswell as our distribution partners, to develop ourproducts and services, as CPM readers willhave seen with our Real Results partnerships ––an initiative that we are looking to grow. Farmersare helping us to define and develop the solutions they need, not the ones that we thinkthey need. You’ll read firsthand in this issue fromsome of the 50 farmers who trialled Revysol ontheir own farms last season, what they thinkabout the chemistry and how they will use it.

Of course we’re very pleased to be launchingthis new innovation but we do recognise the challenges that the industry is facing at themoment regarding the weather. We do hope

that the strong partnership we have with our distribution partners, agronomists and farmerscan help navigate the challenging months ahead.

As a business, agriculture really matters to us–– in 2019 we spent about €900 million for R&D to support BASF’s innovation pipeline for agriculture. By 2028, BASF will launch over 30new products in crop protection, biologicals, digital solutions and seeds.

Sustainability criteria are firmly embedded in our entire R&D process to identify and furtherdevelop those compounds that benefit both farmers and the environment.

Our pledge as a business is to create chemistry for a sustainable future. We can only do this by finding the right balance for farmers,agriculture and future generations.

I’d like to thank the CPM team for all of their hard work on this issue and also for their enduring partnership with us. I’d also like to thank the many farmers who are working with us to find the solutions for farming’s tomorrow.

Triazoles - A star is born Last month marked the official launch of Revystar XE ––a fungicide containing a shiny new azole, Revysol, and BASF’s flagship SDHI, Xemium.

Innovation Insight - Mission impossible?When the decision was made by BASF to bring a new triazole fungicide to market, an entirely new approach was needed.

Research Briefing - A revylation in the field?Revysol has a chemistry that may translate into more spraying opportunities and reliable performance.

Research Briefing - Rising to the septoria challengeAn insight on a series of trials which set out to answer many of the questions about the performance of Revysol.

Technical

4 crop production magazine january 2020

what you’d class as innovation.But Revysol's route to thegreenhouse was only the

start of the story. What’sjust as interesting is how

it’s been evaluated inthe field. Here, I’m not

just talking about theextensive trials programme,

of which the work undertakenin the UK by ADAS is

impressive enough. With the 50Real Results farmers, BASF hasalso striven to redefine in-fieldevaluation. Armed with ADAS’sAgronomics, which puts scientificrigour into on-farm trials, theRevystar XE evaluations not onlyput the new technology into thehands of farmers but give theindustry an honest and openforum in which to discuss theresults.

The Revysol story doesn’t evenend there, though –– indeed youcould say it’s a journey farmershave only just embarked on.We’ve learnt to our cost what happens when too much relianceis placed on a single technicalbreakthrough –– it’s why our fieldsare infested with blackgrass andour oilseed rape with cabbagestem flea beetle. We simply cannot afford to be thwarted byseptoria, but if our sole strategy issimply to seek a more powerfulproduct to stem its rise, wedeserve to lose the battle.

The problem with fungicideresistance, though, is that it’s contagious. Plaster your fieldswith herbicides and you’ll giveyourself resistant weeds, butthey’ll by and large stay wherethey are. Cook up a super-resistant septoria population, however, and it’ll spread, even to those growers who act responsibly to avoid it.

With chlorothalonil (CTL) fallingaway, the risk of resistancebecomes that much greater. It’stempting to ask whether Revysol,with its greater efficacy and longer

application window, will replacethe gap left by this multisite. But the answer from those whoalready have experience of using the new chemistry, is that’sprobably the wrong question to ask.

And that’s the next chapter ofthe Revysol story –– the part thatstarts here and that hasn’t yetbeen written. How it’s played outwon’t depend on the ingenuity ofscientists but the pragmatism offarmers. It won’t be so muchabout mixing modes of action, as a complete change of mindset,and chemistry won’t be thedefault go-to solution but part of a toolbox.

That’s not to say that new technology won’t retain its key roleagainst disease, however, andthat’s another interesting aspectabout Revysol. It’s the first newfungicide to be introduced alongside the new digital farmingplatform xarvio. Set for launchlater this year is xarvio’s FieldManager, which combines dataon product efficacy with local climatic and crop data on yourfarm to give you a tailored recommendation on when andwhat to spray.

Revysol’s vast datasets arebeing plugged into FieldManager’s clever algorithms, andexpect this to be a feature of thefuture –– it won’t be so muchabout relying on the new chemistry to perform as harnessing technology that

What’s the story?

Tom Allen-Stevens has a170ha arable farm in Oxonbut finds it easier to tell the story than put it [email protected]@tomallenstevens

When I first started in agricultural journalism over 20years ago, there were timeswhen barely a month would goby without the launch of anothernew triazole.

The pipeline soon dried up, however, and many of us thoughtprothioconazole, introduced in2005, was the last of this criticalfamily of chemistry that wouldcome to UK farms. As the yearshave passed, prospects of a newazole have only become moreremote with each new seeminglyunsurmountable barrier that’sbeen cast in the way: Annex 1 listing, the Precautionary Principle,endocrine disruption, not to mention the rise of septoria resistance.

So just the fact that today, in2020, Revysol has succeeded inits passage from discovery togreenhouse to regulatory scrutinyto launch is a story in itself, andwhy the CPM team were absolutely thrilled to have theopportunity to tell that story.

For me, perhaps the most fascinating aspect is the determination of both scientistsand those in regulatory affairs atBASF to overcome those barriers.From the moment the decisionwas made to embark on MissionImpossible, every skillset andtechnical resource appears tohave been focused towards asuccessful outcome. The stepsthe research teams took redefine

ensures the minimum usage gets the maximum effect.

So all of us at CPM would reallylike to thank BASF for sponsoringthis special issue, and we’reespecially grateful to those in theR&D teams and others involved inRevysol who have shared theirstories on how they achieved theseemingly impossible. We oftenhear of the €250M cost of bringing a new fungicide to market, but what lies behind thisfigure are years of dedication bycommitted individuals passionateabout progressing agriculture,and it’s a privilege to relay that,although the 24 pages here hardly does the story justice.

But this story’s only half written.As we enter a new decade, wemay be entering a new phase ofagriculture. If Revysol’s to be atrue success, we’ll look back onthis moment and realise it was thepoint disease control itself movedon, and maybe you’ll ask yourselfwhat part you played in that story.

Smart spraying techniques are set to revolutionise herbicide application.Will decision-support platforms do the same for fungicides? (Picture: Bosch)


”“

The last new azole to hit the UK marketwas prothioconazole in 2005 but the fungicide development team at BASF havejust written a new chapter to a book thatmost people thought was finished. ProfJohn Lucas of Rothamsted Researchdescribes the discovery as ‘courageousand an important addition to the fungicideportfolio for a number of reasons.’

“The first cereal azole, triadimefon(Bayleton) was introduced into the UK in1976, more than forty years ago, and therewere subsequent generations of azoleswhich arrived throughout the seventies,eighties and early nineties,” he explains.

Tebuconazole, epoxiconazole and metconazole were in this last wave of chemistry and brought a marked improvement in disease control over theazoles that had gone before them. Thearrival of a new group of chemistry, the Qols(strobilurins), seemed to outclass the

performance of the azoles and the development race effectively stopped.

Fast forward a decade and septoria(Zymoseptoria tritici) populations in the UKand Ireland were starting to show a notableincrease in the frequency of isolates withreduced sensitivity to azoles and the strobilurins had failed altogether. This wasthe backdrop to the launch of a new azoleprothioconazole from Bayer.

“Prothioconazole was a big step forward,not just because of its efficacy on septoria,but for the other diseases it had activity on,such as eyespot,” highlights John. “It alsoproved that you can find new and desirableproperties in a well-explored area of chemistry, and that azoles still had much tooffer,” he comments.

New generation“The arrival of a new generation of SDHIfungicides for use in cereals a few yearslater meant few people expected further newfungicides to emerge from the azole class ofchemistry.”

John describes the azoles as ‘a remarkable group of chemistry’ which hasprovided a multitude of fungicides for use inagriculture, where the target site is the fungalsterol-14 -demethylase enzyme, commonlyknown as CYP51. But azole molecules havebeen equally as effective as human medicines and, ironically, it’s their success in both of these fields that has led to thegradual removal of many azole fungicidesfrom the market.

In humans, azoles can be used for thetreatment of oestrogen-dependent diseases,such as in breast cancer therapy. Whereasthe inhibition of CYP19 (aromatase) is the

A star is bornTechnicalTriazoles

Last month marked theofficial launch of Revystar

XE – a fungicide containinga shiny new azole, Revysol,

and BASF’s flagship SDHI,Xemium. CPM takes a

look at the evolution of fungicide insensitivity that

the new chemistry will playa part in managing.

By Lucy de la Pasture John Lucas explains that resistance to azoles hasdeveloped relatively slowly and doesn’t seem toimpact all compounds equally.

A remarkable group of

chemistry.

working principle for tumour therapy, it’s anunwanted side effect of azoles used asfungicides or antifungal drugs and it’s thispossibility ‘dual-activity’ that led to the concerns over endocrine disruption (ED)when the EU moved to a hazard-based system for the registration of agrochemicals.

With epoxiconazole under risk from theED criteria, BASF set out to screen azolemolecules to find one that didn’t act onCYP19 so wouldn’t have any endocrine disrupting risk. And as a result, the UK nowhas the first new azole to gain registration asa fungicide for 15 years and it has come at avery interesting time in terms of fungicideresistance management.

“The textbook says that once a fungicideclass has been compromised by the development of resistance, all compounds in that class will most likely be affected. We now know that this is an over-

s


simplification, and the azoles are a primeexample,” explains John.

“By comparison with other single-siteinhibitors, like the MBCs and QoIs, resistance to azoles has developed relativelyslowly, and even when present, it doesn’tseem to impact all compounds equally.

“CYP51 has turned out to be not only anexcellent target to inhibit, but also a highlyconserved protein with tight constraints onwhat mutations are tolerated. Over the yearswe’ve seen gradual erosion of efficacy inpathogens like Z. tritici as CYP51 haschanged over time in response to selectionby fungicides and other resistance mechanisms accumulate, such as efflux ––where the azole is pumped out of the cellbefore it can affect the target site –– andover-expression, where the increase in theamount of CYP51 means more fungicide isneeded to inhibit it. But no complete breakdown in efficacy has occurred.”

Possible plateauADAS principal research scientist, Jonathan Blake presented AHDB’s fungicide performance data at its AgronomistConference which took place last month. He believes that the results indicate thatwe’ve now reached the point where there’sbeen little further evolution in the septoriapopulation, according to the results ofRothamsted Research early season monitoring in 2019, with a possible plateauin the ‘older’ azole activity now reached.

In the wider context, BASF monitoringacross Europe has detected a clear andcontinued shift in the sensitivity of the septoria population to prothioconazole. Dr Rosie Bryson, BASF’s senior principal scientist, explains that dry seasons, such as 2017, seem to trigger a bigger shift insensitivity the following year, possiblybecause more of the ‘fitter’ pathogens

survive the adverse conditions.“Up until now, over 60% of the fungicides

applied to the wheat crop across Europehave contained either prothioconazole orepoxiconazole. We’ve identified cross-resistance between the two azoles, mostlythis is found in Ireland and the UK becausethe weather conditions favour septoria development, putting the septoria populationunder higher selection pressure because offungicides needed to control epidemics.”

Rosie explains that when talking aboutinsensitivity to azoles it’s mutations at theirtarget site, CYP51, in the septoria pathogenthat are most often referred to. In the fieldthe reality is that the situation is very muchmore complicated.

“Each septoria isolate with insensitivity toan azole has a complex of CYP51 mutations,with nine main haplotypes representing 85%of the European population.

“Each mutation effectively changes theshape of the target site which makes it more

difficult for the fungicide molecule to bind,meaning it can’t as effectively inhibit theCYP51 enzyme. Even with complex haplotypes, such as G1 which has sevenmutations, some of them will have a smallereffect than others, but generally the morecomplex they are then the less sensitive theseptoria isolate is to fungicides,” explainsRosie.

This high level of background insensitivityin the septoria population makes it a challenging time to launch a new azole fungicide. “When epoxiconazole wasreleased the septoria population was still sensitive and 15 years ago when prothioconazole came along, the populationhad probably begun to shift but was very different than the make-up of the populationtoday,” she says.

It begs the question, what makes Revysol(mefentriflucanazole) different? Rosie

explains that the new molecule belongs to anew class of azoles and is an isopropanol.The isopropanol “linker” on which the azoleis attached gives Revysol’s chemical structure a shape that’s different to all theother azole molecules and a unique ability to change spatially.

“In the Revysol molecule, the triazole ringsits on the ‘neck’ of a flexible isopropanolunit. This unique chemical constellationallows the molecule to assume different conformations easily –– bound andunbound.”

When Revysol ‘docks’ on to CYP51, itswitches from the unbound to the boundform (which resembles a ‘hook’) and bindsto the target enzyme up to 100 times morepowerfully than conventional azole fungicides. It’s this ability to adapt and beflexible that makes Revysol capable of coping with the small changes in shape atthe CYP51 target site caused by mutations.

“Its flexibility means it’s able to adapt its

Rothamsted Research early season monitoring, 2019

Source: AHDB, 2019.

Azole efficacy on Zymoseptoria tritici (2001–19)

Protectant activity at full rate.Source: AHDB, 2019.

Rosie Bryson explains that the flexibility of theRevysol molecule means it can adapt its shape tobind with CYP51, even where the most complextarget site mutations have developed.

s

Triazoles


shape to bind with CYP51 even where themost complex target site mutations havedeveloped,” explains Rosie.

As a result, Revysol has consistently been performing at a level above the currentbest-performing azole, prothioconazole, infield trials and is obtaining a similar level ofseptoria control to that expected from the‘newer’ azoles when they first came on to themarket, before insensitivity evolved.

“In glasshouse work we’ve found Revysolcan control all of the septoria haplotypescurrently found across Europe,” adds Rosie.

Asked whether this strong level of performance can be expected to continue,Rosie says she’d love to be able to give adefinitive answer to the question. The truth isno-one knows what will happen and Johnbelieves Revysol is highly unlikely to escapethe evolution of some sort of resistance within some pathogen populations.

Another mode of actionHowever, both scientists agree that theindustry is far better informed in recent yearsand have learned lessons from the activeingredients that have succumbed to fungicide resistance. One of those is to protect it with another mode of action withsimilar efficacy and this is why Revystar XEcontains the SDHI, Xemium (fluxapyroxad),deemed essential for sustainable resistancemanagement.

Even though SDHIs have seen some erosion in efficacy over the past three seasons, they’re still giving good levels ofperformance in the field. Rosie believes it’slikely their activity will slowly erode further intime, but in 2019 there appeared to be amuch smaller shift than happened from 2017to 2018.

“There’s a wide perception in the field thatSDHIs didn’t work as well in 2019, comparedwith 2018, but what’s actually happened isthat the effect of the shift in sensitivity thathappened in 2017 wasn’t really noticed in 2018 because it was so dry, and consequently the disease pressure was low.

“BASF insensitivity testing across Europeshows there’s been no statistical change insensitivity from 2017–2019 across Europebut it identifies a higher level of variability,with the greatest range of mutations presentin the UK and Ireland and declining in aneastward direction across the continent,”explains Rosie.

Since the first changes in septoria sensitivity to the SDHIs, detected in 2016,the evolution has been characterised by aseries of target site mutations giving partiallevels of resistance and a slow decline inefficacy rather than the step-change in

The nine main Zymoseptoria tritici haplotypes

The table shows the nine most common Zymoseptoria tritici haplotypes found in the European population and the CYP51 mutationsassociated with them. Source: Huf et al., 2019.

BASF pathotype monitoring in UK, spring 2019

UK early season monitoring, n=44 (up to end of April)Source: BASF, 2019.

activity that happened with the Qols in 2003.“In monitoring, we’ve found the two

most dominant mutations are C-T79N and C-N86S, both are moderately adapted. Thesevere C-H152R mutation has only everbeen found to be present at very low levelsin the spring so it does seem to have a fitness penalty which means it doesn’t overwinter well,” she explains.

The azole and SDHI components ofRevystar have been balanced to producea fungicide which can perform at a levelgreater than could be expected from thesum of its parts, adds Jonathan. He’s conducted Matrix trials at ADAS whichexplore the dose rates of each activeingredient alone and in mixture to identifywhether there are any antagonisms or synergies between them.

“Using some complex mathematics, it’s possible to compare the observed performance of Revystar against its predicted performance. It’s a very toughtest and very unusual to find a fungicide

that gives a better than predicted performance,” explains Jonathan.

“In 2018 we found Revystar performance almost perfectly fitted the lineof prediction and in 2019, it exceeded it.That indicates there is a possible synergybetween Revysol and Xemium, andRevystar may perform as well, or betterthan you’d expect from the sum of itsparts,” he says.

Although the arrival of Revystar isundoubtedly an exciting development andwill provide a much-needed option in afungicide market where active ingredientsare being lost at an alarming rate, it’simportant not to underestimate the importance of stewardship in preservingits activity, believes John.

“We’re not going to get out of an evolutionary arms race with the septoriapathogen, but we are getting smarterabout co-formulation, as Revystar demonstrates. We also have to be smart about how we use chemistry and

remember Revystar will only take us backto where we were in terms of fungicideefficacy,” he says.

Integrated pest management will also play a crucial part in Revystar stewardship, says Rosie, with the adoptionof more septoria resistant varieties centralto an overall resistance management strategy.

“It’s going to be just as important to try and hit the right timings in the field,even though Revystar has good curativeactivity, and to dose appropriately bymatching the dose to variety susceptibilityand disease pressure,” she advises.

John agrees selecting varieties withmore durable resistance and both smarterformulation and use of chemistry areimportant tools to slow the development offungicide resistance. He’s witnessed manyclasses of fungicide come and go over theyears and warns, “the behavior of themicrobial world won’t change, even afterBrexit!” n

those found in mammals,” notes Rob.The breakthrough came with the

development by the biochemistry team of new enzyme assays. Dr Ian Craig, a computational chemist, joined the team in2011. “The assays test the efficacy withwhich the DMI chemistry, which includesazoles, inhibit the fungal target site, CYP51–– blocking this enzyme prevents a fungalcell from producing ergosterol causing it to

They say necessity is the mother of innovation and you could argue it’s neverbeen more necessary to bring new fungicide chemistry to growers. But perhaps the true innovation behindRevysol, the first new azole to reach theUK market for 15 years, has been theapproach BASF has taken in the face ofthe tough EU regulatory regime.

“With Revysol we put the cart before the horse,” notes UK and Ireland head oftechnical management Rob Gladwin. “The EU’s aversion to conventional crop protection is a major challenge for the industry, growers and eventually for consumers.

“For the azoles there is the backdrop ofconcerns over endocrine disruption, so we

addressed this head on –– right from thestart, our research teams looked not just totarget enzymes in the fungal pathogens, butalso specifically for chemistry that does notharm mammals.”

But it’s not just Revysol’s regulatory profilethat’s of note, according to Dr Martin Semar,senior principal scientist with BASF and oneof the first to test it in the field. “To have anactive that’s so effective against so manydiseases in so many crops, that’s reallyrare,” he says.

Great uncertaintyThe quest for new chemistry started aroundeight to ten years ago, Rob recalls. “Thedecision was made to look for a new azole.The efficacy of current chemistry was shifting and there was great uncertainty overwhether the majority of the existing azoles inthe market place would get through the verydifficult EU approval renewal process. BASF has always understood the need forthe precautionary principle, but we feel it’sbeen abused –– to succeed it’s not justabout getting the science right, but also the politics.”

So in a new molecule, there were two keyfeatures the BASF research teams weretasked with finding –– the right selectivityand also a favourable regulatory profile. “The difficulty is that the target enzymes infungal pathogens are closely related to


MissionImpossible?Technical

Innovation Insight

When the decision was madeby BASF to bring a new

triazole fungicide to market,an entirely new approach

was needed to ensure itpassed through the EU’s

difficult approvals process.CPM tells the story.

By Tom Allen-Stevens

Right from the start, research teams lookedspecifically for chemistry that does not harmmammals, recalls Rob Gladwin.

With Revysol we put the cart before

the horse.”“

For Ian, both the discovery of this molecule with its unique properties as wellas the journey to find it represent the bigachievements behind Revysol. “DMIs have a mode of action which is inherentlyinteresting. But the approach we took hastaken our work in a new direction and hasbecome the standard way we start theprocess of new active ingredient development,” he notes.

“We do everything we can to put forwardthe right molecules into our developmentpipeline so we don’t have problems later, butwe see so many that fail. It makes it all themore rewarding when you find one that succeeds.”

But so far, the new molecule had only got as far as the lab. How would Revysolperform in the field? Martin put it to the testagainst a broad range of key diseasesacross globally important commercial crops.“When we saw how highly active it wasacross such a wide spectrum of situations,we realised this was the one to take forward,” he says.

Shifted strains“It’s not only the high activity on major diseases such as Septoria tritici –– it’s not so difficult to find this. It’s also the selectivity–– having the ability to use it across a largenumber of commercial crops in many different countries. What we also noticedwas that Revysol was effective on shiftedseptoria strains. It’s the combination of thesefactors that made it a potential blockbuster.”

After the first initial and promising results,the team extended the testing program,broadening it to more crops and diseases,first in the greenhouse then on a fewresearch stations and then globally undervarious conditions.

The regulatory studies of new active substances also continued in parallel withthe efficacy work. “The development ofRevysol heralded this new focus in our R&Dactivities, targeted on the regulatory profile,which now start at a much earlier stage and

die,” he explains.With the new assays the team could

quickly screen a large number of moleculesin their quest for those that were highly effective. What was entirely new, however,was the screening programme runningalongside this. “In tandem, the team set upsimilar assays to test the chemistry for itseffect on CYP19. This enzyme target site isfound in mammals and is associated withunwanted side effects.”

The team screened hundreds of compounds and received very quick feedback, not just on how effective theywere, but also how safe. And this is whereIan’s specialism comes in, but what does acomputational chemist do?

“I work closely with the chemistry teamsand use algorithms to effect different simulations of how a molecule would bind to a target site and inhibit an enzyme,” heexplains. “It’s a branch of chemistry that’s

been in use for some time, but the technology we employ today is highlyadvanced. The 3-D models we produce help chemists prioritise and then narrowdown the molecules they want to investigateand develop.”

Together, the team discovered a uniqueproperty of an entirely new family of triazoles–– this molecule has a ‘hook’. “It’s an isopropanol linker. This moiety is a small partof the larger molecule and it’s unique for aDMI. We synthesised it and noticed verystrong fungicidal effects.”

Ian’s simulations showed the ‘hook’ allowsthe molecule to bind very tightly to the targetsite. “What’s unique is that it’s flexible ––it not only fits perfectly into the CYP51 binding site but it also has the flexibility toadapt if this binding site changes, unlikeother azoles. We think that helps with thecontrol of septoria isolates that have evolvedmutations,” he notes.


What is the ‘hook’?

Revysol’s mobility and durability

s

Martin Semar says it’s very rare to have an activethat’s so effective against so many diseases in somany crops.

Innovation Insight

Source: BASF, 2019

Source: BASF, 2019

s


Innovation Insight

Tests in the BASF lab and the glasshouse atLimburgerhof confirmed how highly active Revysol

was across a wide spectrum of situations.

One property the formulation chemists noticedabout Revysol is that it has very poor solubility.

Marcel Patrik Kienle found up to 65% of the appliedactive ingredient got into the leaf within one day,most of this within just six hours.

in far greater detail,” explains Martin. “This is different to the studies we carried

out in the past where biological optimisationhad the higher priority. All told, it was a longand expensive process, but we built up acomplete picture of both Revysol’s biologicalefficacy and its regulatory profile.”

The final piece of the jigsaw was to makethe molecule mobile within the plant andensure the product’s stability. Dr ChristianSowa is a formulation chemist with BASF.“The first thing you do with a new moleculeis to get to know its structure and its solubility profile. That can be a particularchallenge with DMIs as they tend to crystallise, so we use an emulsifiable concentrate (EC) to deliver the right results,”he explains.

“But one property we noticed aboutRevysol is that it has very poor solubility, sothere’s a lack of suitable solvents. That leadsyou towards complex solvent mixtures,which have their drawbacks in terms of howthey may interact in the can or in thesprayer. The upside is that once in the leaf,the low solubility helps –– Revysol forms aninner leaf reservoir which slowly moves

through the leaf, ensuring long-lasting protection.”

Formulation chemistry has moved onapace since the last azole came to market,however. A new aspect in this field again iscomputational chemistry, which is oftenbrought in to tailor formulations and modeldifferent scenarios. “You have to know how itwill behave when the product’s scaled up ––you don’t want any surprises when it’salready in use by thousands of farmers.”

Revysol’s broad range of uses was a further challenge –– it’s available in no fewerthan 30 different formulations to cater for thedifferent countries and crops in which it’ll beused. There’s also the interaction withXemium once formulated as Revystar XE.“Xemium has different properties –– it creates crystal depots on the leaf surface,and the crystals can form in the can if youhave the wrong formulation,” notes Christian.

Revysol passed through a gradualprocess of refining, assessing and addressing questions raised. “Some teststake many months until you have a result,which may be a nice outcome, but raise tenmore queries. But what we try to ensure is aformulation that is flawless and performsinvisibly –– success is when the farmer doesn’t even notice it,” he says.

It’s also a key requirement that the delivery to the target is optimised, and it wasDr Marcel Patrik Kienle who ensured thiswas the case. “What we do is test what happens in the field through lab experiments. We look at how much stays onthe leaf, how quickly it’s taken up followingapplication and its movement to the leaf tip,”he explains. “Revysol is barely soluble inwater, so not that mobile.”

Environmental influencesSo how quickly is it taken up into the leaf?“We found up to 65% of the applied activeingredient got into the leaf within one day,most of this within just six hours. This isimportant as, once inside the leaf, the activeis protected from environmental influenceslike rainfall or UV-light,” notes Marcel.

“There’s also a remarkably high uptake incold conditions –– 20% is taken up in thefirst six hours, which compares with a standard formulation where you’d expectnearer 5%.”

Droplets were placed on the leaf betweenthe stem and the leaf tip to assess howquickly Revysol moves through the plant.“You’re looking for a good, even distributionand don’t want it to move too quicklybecause that can cause phytotoxicity andyou get scorch. Equally you’re looking forlongevity, so that its strong curative actionlasts. We found 10% of the active made its

way from the application area into the direction of the leaf tip within a week.”

Numerous small-plot trials (see article onp14) and on-farm field-scale evaluations(see article on p17) have now demonstratedthe properties of Revysol. “But what’s takenthe industry by surprise is the speed withwhich it’s passed the EU regulatory hurdles,”says Rob.

“With Revysol we had the quickestprocess from submission for active substance approval to registration of the firstformulation. BASF developed Revysol byoptimising exceptional biological efficacyand an outstanding regulatory profile.”

The registration was also designed to beBrexit proof –– applications for Revysol weresubmitted both through the EU and separately to UK’s Chemical RegulationDirective (CRD), in case the UK had left theEU before approval was granted.

“We’ll be following the same procedurewith future product approvals to ensure UKgrowers always get access to the bestchemistry available,” Rob assures. “Butapproval for Revysol is really good news forglobal agriculture as well and a stunningendorsement of our R&D and regulatoryteams.

“By proactively addressing all of the concerns of the toughest approvals systemon the planet, we’ve put a truly innovativeproduct in the hands of growers that willallow them to progress cropping systemsaround the world.” n

When the team from BASF reviewed theresults from the first trials of Revysol(mefentrifluconazole), even they were surprised, according to Dieter Strobel,responsible for the company’s technicalmarket development for cereal fungicidesin Europe.

“We saw Revysol was giving stunning efficacy, even better than we’d expectedand far superior to other chemistry. Theadvantage it was showing grew over timedue to the continued erosion of efficacy inthe older azoles,” he comments.

“In high disease pressure situations, the strength of Revysol was particularlynoticeable. Where conventional productswere struggling, it continued to provide control of septoria.”

In total more than 1,000 field trials werecarried out using Revysol throughout Europeand by summarizing all the data BASF wereable to link aspects of its performancedirectly to some of the new azole’s chemicalproperties and its clever formulation.

“Revysol has very low solubility, so it wasa real challenge to our chemists to formulatea product that would be easily taken up by

plants. They found a way to formulateRevysol in a way that makes it available asfree molecules and not crystals in an emulsifiable concentrate (EC),” he explains.

The work of the formulation chemistsmeans Revysol is taken up very quickly byplants, which is an essential property for anazole fungicide to be effective.

“Quick uptake makes an azole effective,but we learned from our experience withepoxiconazole that it can also mean that itslongevity of performance may be limited. In trials, Revysol clearly had a longer-lastingefficacy than either epoxiconazole or prothioconazole, which was surprising. We’dexpected its quick uptake to mean Revysolwould have a short duration in the plant, butthis isn’t the case,” explains Dieter.

Formulation wizardryHe explains the unexpectedly long durationof Revysol’s action as being down to the solubility of the molecule. It’s made ‘artificially’ soluble using formulation wizardryto get quick uptake into the plant, but onceinside the leaf it reverts to its normal insoluble state.

“It’s so insoluble that only a few Revysolmolecules at a time can make it to the end of the leaf. In other words, it has a low but consistent level of translocation in the leaf.”

Rather than being a disadvantage, thehigh intrinsic efficacy of Revysol means thattraces in the leaf are enough to control theseptoria pathogen. The advantage of itsslow rate of movement is that once theRevysol has got into the leaf, which happensquickly, it remains as a rich inner-leaf reservoir to constantly release low levels ofactive substance towards the leaf tip.

A revylation inthe field?Technical

Research BriefingRevysol has a chemistrythat gives it many useful

properties in the field. CPMfinds out how this

may translate into morespraying opportunities and

reliable performance.

By Lucy de la Pasture

Dieter Strobel explains that Revysol’s quick uptakemeans it isn’t influenced by temperature in thesame way as conventional azoles, where coolweather can limit uptake.

Chemistrythat will bringcontrol back to

the grower.

So how does Revysol’s quick uptake butslow translocation translate into propertiesthat are of benefit in a field situation?

“Its rapid rainfastness, just 15 minutes,can be explained by Revysol’s fast uptake.When leaf wetting occurs, the chemistry isalready protected within the leaf so it can’tbe washed off,” explains Dieter.

The same dynamic properties of Revysolalso make the fungicide very stable to UVlight, which is known to influence the performance of some other azoles.

“We’ve experienced some hot summers inrecent years, and prothioconazole gave arelatively poor performance in the fieldwhere high UV conditions occurred, whichcan be linked to UV-degradation of the fungicide. Revysol is held within the leaf sois protected from UV light,” he explains.

A further benefit of Revysol’s chemistry isthat its quick uptake means it isn’t influencedby temperature in the same way as conventional azoles, where cool weather s


”

“


Research Briefing

can limit uptake. “All of these characteristics –– rainfastness, UV stabilityand temperature independence –– all meanmore opportunities to go spraying without concerns about reductions in efficacy.”

Benefits finderBASF has developed a ‘Benefits Finder’ app.which helps illustrate how much the spraywindow can be ‘stretched’ when using thenew chemistry. Dieter gives an examplewhere over the period of a week, the rainfallamounts meant six days were possiblespray days (threshold: 5mm/day). Of theseonly three were optimum for the applicationof conventional products, while Revysolwould perform on all six days –– even whenthe temperature dipped below 13oC andthere was rainfall forecast.

Steve Dennis, BASF head of businessdevelopment in the UK, says the effects ofclimate change mean we’re experiencingmuch more variable weather patterns in the

UK, with an increasing tendency to get‘stuck’ within prolonged periods of wet or dryconditions.

“Adding to the difficulties is that septoriais becoming more adapted to our currentchemistry. The combination of the loss ofcurativity from azoles and disruptive weathermeans it’s becoming harder to get fungicide

Systemic biotest wheat

Leaf uptake

Application at basal zone, inoculation of whole leafwith brown rust 21 days after application.Source: BASF, 2019.

timings right,” he says.Steve sees Revysol as “chemistry that will

bring control back to the grower.” While heemphasises the importance of correct fungicide timings in providing optimum protection to the leaves of the upper canopy,the properties of Revysol mean that it doesn’t matter as much if the weather does intervene.

“Weather is unpredictable, especially inthe UK, and fungicide application is all aboutthe weather. Revysol means there’s lessneed to predict, which takes some of theworry out of application.”

In 2019, heavy rain fell across the UK andIreland in June, a couple of weeks after flagleaf sprays had been applied, and septoria“went mad”. It was a disease situation thatwould have been a lot worse if chlorothalonil

More spray days

The properties of Revystar XE in the field meanmore spray days.Source: BASF Benefits Finder app, 2019.

Revysol leaf uptake in one day equals the amountof prothioconazole taken up in a day.Source: BASF, 2019.

s

Dr Steven Kildea has been keeping a keen eye onRevysol in trials at Teagasc’s Crops ResearchCentre at Oak Park in Carlow. Septoria pressure isat its highest on the Emerald Isle, which marks thewesterly horizon of wheat growing in Europe.It was Ireland where the first slip in SDHI activitywas experienced, with the UK following closebehind. Since then, it’s CTL that has been supporting fungicide chemistry and may be partially responsible for stabilising the situation,he believes, with little further erosion of SDHIactivity seen since 2017.

“New chemistry is very welcome and in trials,we’re seeing Revysol moving the yield contributionfrom the azoles back up to where they used tobe,” he says.

Disease development is so strong in Irelandthat fungicide programmes need the most highlyactive ingredients throughout the programme, withas much emphasis on the T1 timing as at the T2.Diversity is the key to resistance management asit allows growers to potentially reduce the doseused or the number of times individual actives are actually applied, so Steven is keen to includedifferent chemistry in fungicide programmes.

“We have the opportunity to use fungicidesbetter, having learned from our past experiences.The septoria pathogen will most likely evolve in

response to selection pressure and we’re notstarting with a native population of septoria. It’sthe pathogen’s ability to accumulate mutationsthat poses the biggest threat to Revysol.

“We’ll need to be very careful about how weprotect this new chemistry, otherwise we won’t get the same amount of time we’d had with the other azoles before their performance waseroded.”

Part of that process will be careful agronomicchoices, which make a big contribution to diseasecontrol, he says. “It comes down to local decisions– matching the rate of fungicide appliedto disease pressure will reflect the season andagronomic factors, such as varietal resistance and planting date.”

“Under Irish conditions we need very high cultivar resistance before you can reduce the rateof fungicide without affecting yield. We still seeyield responses to fungicides in cultivars with septoria resistance ratings in the high 7s.”

Ramularia is a disease that poses one of thebiggest problems with the imminent withdrawal ofCTL. Teasgasc has conducted trials to assess thecontribution of different actives to its control inboth winter and spring barley at the T2 timing.

“As we anticipated, CTL gave the best controlof ramularia. We found the performance of SDHI

The Irish experience

applied at full-rates to be disappointing, so resistance has had a significant impact on theirefficacy. Proline (prothioconazole) has also beensignificantly impacted but it gave better controlthan we’d anticipated and above that of the alternative multisites, folpet and mancozeb.

“Revysol gave decent control of ramularia in the trial, offering a level between CTL andProline, so it will help take the pressure off prothioconazole. Whilst the loss of CTL will clearly be felt, we will be able to manage ramularia. The crop won’t be completely clean but that’s not necessary, as long as grain numbers and fill is protected enough tomaximise yield potential.”

Steve Kildea believes we have the opportunityto use fungicides better, having learned fromour past experiences.

Research Briefing


Using Revystar XE will take some of the worries away when making spraying decisions,says Steve Dennis.

(CTL) hadn’t been widely used, believesSteve.

“CTL is a long-term, effective protectantfungicide and has given flexibility if followingtimings haven’t been quite right, so it hid theeffects of less than optimum fungicideinputs. In a world without CTL, we’re goingto have to be a lot more on our toes,” hecomments.

Revystar XE (mefentrifluconazole+ fluxapyroxad) will bring much-needed flexibility and curativity and the BASF

recommendation is for a programmedapproach at T1 and T2 timings, says Steve,though he accepts that in many situations itwill be used just once, at T1 or T2.

“The evidence for using Revystar at T1 isstrong and if there’s a wet period, then it reallyis the product of choice,” he believes.

The full label rate for Revystar is 1.5 l/ha,but agronomists will use their discretion todose appropriately according to disease pressure and varietal resistance, he adds.“Revystar at 1.0 l/ha offers a great performance and value compromise, but higher rates may be necessary in some circumstances. There may also be situationsat T1 where 0.8 l/ha will be suitable but at T2, I don’t advise using at rates below 1.0 l/ha,” he says.

Apical translocationSteve says the very slow apical translocationof Revysol means it has a very good cropsafety profile, avoiding some of the scorcheffects seen with faster moving fungicides.

Revystar will also offer good control ofbrown rust, where its performance is equivalent to market standards, says Steve.“For yellow rust control, the addition of a strobilurin will be beneficial. In terms of mildewand eyespot control, Revystar’s

performance is equal to prothioconazole.”The demise of CTL will leave one of the

biggest holes in programmes to controlramularia, where it has become the mainstaysince instances of resistance have beenreported to single-site chemistry, includingazoles, strobilurins and SDHIs.

“We’re seeing Revysol maintain its performance against azole-resistant strainsof ramularia compared with prothioconazole.It’s a disease that develops in response tostress so it’s important to manage crop stress as well, part of which is good early season disease control.” n

The high intrinsic efficacy of Revysol means thattraces in the leaf are enough to control theseptoria pathogen.

she adds.“In practical terms this means that you

would get the same level of control fromRevysol applied 14 days after infection asyou would with a well-timed prothioconazoleapplication.”

Given the slide in efficacy of the currentazoles, the ability Revysol has to controlinsensitive strains of septoria is of key interest to growers and agronomists, highlights Julie.

“We looked at Revysol’s ability to controlDMI-adapted (azole insensitive) strains ofseptoria by setting up a trial with a number ofdifferent inoculation treatments. We includeda control where we allowed septoria to develop from natural field infestation. For theother treatments, increasing septoria pressurewas achieved by inoculating with local fieldisolates (Hereford), applied when the flag leafwas fully expanded, at either 1M spores/ml(106), 10M spores/ml (107) or 100M spores/ml(108), and DMI-adapted septoria was appliedat 10M spores/ml.

“To put these treatments into perspective,the pressure exerted by the 10M spores/mllevel of inoculation is extreme and 100Mspores/ml is akin to a nuclear strike to the

The unique chemistry of Revysol (mefentrifluconazole) gives the new azolesome key attributes that should translateinto superior performance in the field.Tasked with finding out whether it wouldlive up to expectation, ADAS senior researchscientist Dr Julie Smith set out to testRevysol’s capabilities.

“There are five main attributes that BASFbelieve Revysol has because of its chemistry.These are superior rainfastness and rapiduptake of the fungicide, contributing to strongcurative activity; long lasting performance inthe field; maintenance of efficacy under highdisease pressure; effectiveness against DMI-adapted (insensitive) strains of septoria;and a benefit on resistant varieties,” explains Julie.

To put Revysol through its paces shedesigned a series of field trials using it as a straight rather than the co-formulated product, Revystar XE (mefentriflucoazole+fluxapyroxad).

“To look at Revysol’s rainfastness, we set up a trial where we were able to irrigateoverhead the plots and compare the performance of different fungicides, with andwithout a period of ‘rainfall’ after application.”she explains (see chart right).

“We allowed disease to develop thenassessed septoria levels on the flag leaf

for each fungicide in the irrigated and unirrigated plots and found that Revysol wasthe most rainfast, with only a very smallreduction in control when it was irrigated 15 mins after application.”

Revysol is also believed to have good curative activity and to assess whether this istruly the case, Julie set up a field experimentto compare it with other azoles. The field plotswere inoculated with field isolates ofZymoseptoria tritici on 17 May 2019 and fungicide applications were made at either one, five, 10 or 15-day intervals after inoculation, followed by disease assessmentsat GS65 and GS73.

“The results show septoria control fromRevysol was consistently highest of all treatments, for all application dates, on bothleaf one and leaf two,” she says.

Julie highlights that Revysol is providingmore than 80% control of septoria in a shifted population, even when it’s applied a week after infection.

“On leaf three, there’s also evidence ofstrong curative activity. Revysol has morethan twice the efficacy of the older azoles for all fungicide applications over the 12-day period after leaf two was inoculated,”

Rising to the septoria challengeTechnical

Research BriefingThe efficacy data needed forproduct registration doesn’t

necessarily answer all the questions about the

performance of a new activeingredient. CPM gets an

insight on a series of trialswhich set out to test the

boundaries of Revysol.

By Lucy de la Pasture

The pressure exerted by 100M

septoria spores/ml is akin to a nuclear

strike to the plant.”

“


Septoria on the flag leaf

Source: ADAS, 2019.


Research Briefing

plant,” describes Julie.Fungicides were applied five days post-

inoculation using Revysol (1.5 l/ha), Proline(0.72 l/ha), and compared with an untreatedcontrol. Septoria spores can germinate within

To investigate the long-lasting performance ofRevysol, Julie set out to replicate some of thework that led to the basis of the spray timings we currently aim at to provide the best septoria control –– GS32 (to protect leaf three) and GS39 (to protect leaf one), with the combined timings protecting leaf two.

“We set up a ‘wave’ experiment on five sitesover two seasons (2017-2018). This indicates thefungicide’s flexibility at different spray timings,providing the ‘spray window’,” she explains (seecharts, below).

“The results show the decline in standard azole performance since the original work wasdone, with the levels of disease control from prothioconazole application falling well short of

the ‘curve’. For Revysol, the data shows its performance is pretty much what we’d haveexpected from an azole before their performancewas eroded by the evolution of a less sensitiveseptoria pathogen population.”

While the level of disease on the main leavesthat contribute to yield is a useful assessment,looking at the Healthy Area Duration (HAD) foreach fungicide treatment provides a measure ofboth canopy size and its duration. This data canhelp explain yield effects, highlights Julie, and isalso the most objective and unbiased way ofassessing the performance of a product becauseit’s not just a snapshot in time.

Analysis of yield across all five sites demonstrated a yield response for the

Performing as an azole used toRevysol treatments of just over 1t/ha above prothioconazole at GS39, maintaining an advantage of nearly 0.5t/ha even at the GS39 plus 15 days timing (see chart, bottom left).

“A cross-site analysis of HAD showed thatRevysol treatment produced a much higher HADthan prothioconazole at all the treatment timings,which helps explain the higher yields in theRevysol treatments,” she explains.

The range of spray timings either side of theoptimum timing at GS39 produces a bell-shapedcurve for the yield data. “The shape of the Revysol curve shows there is a spray windoweither side of the optimum timing, further supporting the curative and protectant claims for the new azole,” adds Julie.

Revysol wave experiment Prothioconazole wave experiment

Source: ADAS, 2019.Source: ADAS, 2019.

Source: ADAS, 2019. Source: ADAS, 2019.

Yield, cross-site analysis - five sites 2017-2018

Efficacy against DMI-adapted strains

s

12h of hitting the leaf surface so waiting forfive days before applying the fungicides is a robust test, she reasons. The progress ofseptoria was monitored and Revysol demonstrated its ability to protect the crop

under all disease pressures, including theshifted strains (see chart, bottom right).

“I still gasp when I see 80% of a flag leaf covered with septoria but these are thedisease levels that we achieved with some

The latent challenge

Research Briefing


One of the most difficult decisions to make in thefield is the best approach to take at T1 and T2.To get more insight into this, Julie selected leaveswith little or no disease visible when fungicide wasapplied. When sprayed at GS39 plus five days,septoria was visibly present on the flag leaves at a level <1% but DNA analysis of the septoriapresent inside the leaves painted a very differentpicture.

“The untreated had the highest amount of septoria DNA, as expected, and prothioconazoletreated had significantly more septoria DNA thanthe Revysol-treated leaves. The level of septoriawithin leaves was tracked using DNA analysis ona weekly basis to monitor its progressions andeven in the most curative treatment, GS39 plus15 days, the control from Revysol was still good,”says Julie.

Additional data from Cura Crop research,carried out for BASF in 2017, supports the resultsof the ADAS work, says Steve Dennis, BASF’shead of business development in the UK.

“It’s not until cell death occurs that visual symptoms on the leaf become visible. So by the

time the pycnidia can be seen, the damage hasalready been done within the leaf itself,” heexplains.

The aim of the Cura Crop research was to bust the myth that no visible infection means nodisease, even in a lower disease year.

“Leaf two is generally out for some time without any fungicide protection, so for the Cura Crop work we asked growers for a visualassessment of septoria on leaf two just before theT2 timing and 60% of them thought their cropswere free of disease.

“We collected leaves one and two, to representthe top of the plant, and leaves three and fourwhich received a fungicide at T1. Latent diseaselevels could then be clearly detected by DNAanalysis. At the T2 timing, the vast majority (75-90%) of lower leaves (L3 & L4) were infectedand 50-65% of upper leaves (L1 & L2) were alsoinfected.

“Even though it’s not intended to apply a T2fungicide as a curative, in most cases there islatent septoria present in the upper leaves andinfection on the lower leaves at the time of

application,” he comments.In the ADAS work Julie looked at the effect of

Revysol on spore production. “We induced sporerelease and quantified the number of spores inuntreated, prothioconazole and Revysol-treatedplots. There were significantly fewer sporesreleased where Revysol was applied, resulting ina lower inoculum load to initiate the next cycle ofdisease which will decrease the epidemic in theupper canopy,” she explains.

ADAS also looked at the efficacy of Revysol underdiffering disease pressures using a tsunami experiment at a site in Hereford, explains Julie.

“We wanted to set up different disease levels in asingle randomised trial so we designed a series oftreatments to manipulate disease pressure, rangingfrom very low septoria (<3%) to very high (>75%).Each level of disease was then subjected to fungicide treatment with either Proline or Revysol.”Rain-out shelters mimicked a dry season, while someplots were irrigated and some were inoculated, usinga mixture of field isolates and insensitive strains.

“The results show an increasing separation in the performance of Revysol and prothioconazole asdisease pressure increases,” she concludes.

Source: ADAS, 2019.

Source: ADAS, 2019.

Tsunami experiment, Hereford 2018

Spores produced after treatment

s of our inoculation treatments. But there’svery little difference between the control from prothioconazole and the untreated. Under thehighest inoculated pressure most fungicideproducts would break but Revysol still performed,” she comments.

“The levels of control from Revysol whenunder pressure from the DMI-adapted strainswas good, so this work supports the claimthat it will currently control insensitive strains,”she adds.

The adoption of more septoria-resistantvarieties is part of an integrated approach tocontrolling the disease, but is there still a benefit from applying Revysol?

Julie and her colleague Chloe Morgan

investigated this by setting up a ‘domino’experiment using a range of varieties at different ends of the resistance scale.

“We established three disease pressures,which were natural infestation; natural plus inoculation with field isolates; and natural plus inoculation with DMI-adaptedstrains.

“We found that there was a benefit toapplying Revysol irrespective of the wheatvariety, although when it came to diseasecontrol and yield benefit, these were biggest in the more septoria susceptible variety,” she adds.

“The important thing is that we don’t relysolely on fungicides or varietal resistance,

because doing so is likely to result in a morerapid breakdown of either.

Our programme of work validates theclaims made by BASF about the efficacy ofRevysol in the field. We tested Revysol usingthe most robust methodology available andwere not able to break it,” notes Julie.

“Revysol consistently out-performed competitors irrespective of disease pressure,pathogen insensitivity or wheat variety.Despite the tremendous challenges that wecurrently face, BASF have re-set the clock interms of azole efficacy against septoria leafblotch and that achievement should not beunderestimated.” n

Under a tsunami of disease

In the same year Kent grower Richard Budd

achieved a barn-busting7.2t/ha yield from oilseedrape, on-farm trials with

Revystar XE suggest somecareful tweaks may unlock

similar potential in his wheatcrop. CPM visits to find out.


Considering his heavy Weald clay hasreceived 60mm of rain in the past weekalone, Richard Budd’s current crop ofoilseed rape is looking remarkably spritelyon ground that feels firm underfoot.

“We’ve only managed to get about 40% of our winter wheat drilled this year, but all150ha of the OSR crop is up and away,” hereports. “It looks good, considering it’sreceived two thirds its annual rainfall in thelast six weeks, but I don’t think we’ll get arepeat of last year’s crop.”

That would be quite an achievement,because Richard’s 2019 crop of Campus

yielded an eye-watering 7.19t/ha. It was byfar the highest yielding crop entered in theOilseed YEN (Yield Enhancement Network)and would probably have beaten the worldrecord set in 2018 by Lincs grower TimLamyman (7.01t/ha) had it been officiallyentered and recorded.

But this bounty represents just one of thefascinating features of Stevens Farm, nearHawkhurst, Kent, that Richard farms with hisfather, David. Alongside 900ha of arablecrops (winter wheat, OSR, barley, oats andbeans with spring barley, beans and oats),there’s 125ha of top fruit and 75ha of permanent pasture let out on short-termagreements.

Fairly robustWithin the 2019 wheat area was a field alsoentered into YEN, and within that field was a Real Results replicated tramline trial of BASF’s new fungicide Revystar XE (seepanel on p18). While his farm standard fungicide programme yielded a fairly robust13.89t/ha, the Revystar plots brought in14.88t/ha –– a yield that would also put hiswheat among the top YEN performers of the year.

“For me, farming’s about optimising theinputs to get the best output –– that’s why we

New chemistry reveals its potential

RealResults

Pioneers

use YEN,” Richard explains. “The reportgives you a good, detailed analysis of howyour crop has performed which we use totest and improve how we grow our crops.

“It’s not all about growing the highest-yielding crop, though –– we’re aiming for a yield that’s achievable and sustainable. So we’re not going to travel 20 miles to puton a micronutrient simply because YEN’s

The opportunityto use the new chemistryearly and have the results

assessed using ADAS’sAgronomics has given us athorough insight into how

it’s best used.

s


”

“

The current crop of oilseed rape looks remarkablyspritely, but is unlikely to yield the barn-busting7.2t/ha achieved last year.

Real Results Pioneers


This is the third year Richard has been one of50 growers taking part in BASF’s Real Resultson-farm trials. Across a section of a wheat crop,this has compared the farm standard fungicideapproach at the main two timings with the BASFrecommended programme, usually based onAdexar and Librax.

“It’s been quite exciting to be involved thisyear, because we’ve used Revystar in place ofthe usual Ad/Lib programme,” notes Richard.“The opportunity to use the new chemistry earlyand to have the results assessed using ADAS’sAgronomics approach has given us a thoroughinsight into how it’s best used.”

The trial was placed in the eastern part ofthe field, the area with the most consistent soiltype. The BASF trial plots were interspersedwith three tramlines that received the on-farmstandard. NDVI (normalised difference vegetation index) maps were taken through theseason and these were assessed by ADAS scientists, along with disease levels from samples taken in July. The Agronomicsapproach was then used to compare theresults, using spatial modelling and statistics to allow yield-map data from the combine to be assessed with scientific rigour.

“Last year we had a dry, mild winter andcame into the spring with a good, well tilleredcrop,” reports Richard. “There was a lot of septoria on the lower leaves, but this didn’tdevelop and by May it was quite dry, althoughthere was no sign the crop was under stress.The rain that came in late May and early Junewas really quite timely and we beefed up the T3spray application as a result.”

NDVI images (see below) showed the eastside of the field as more even prior to T1, while‘striping’ found in May and June was “fairlysubtle” and not related to the treatments,according to ADAS project manager SusieRoques. “From mid-July, the NDVI appearedslightly higher in the three BASF tramlines,suggesting that the BASF treatment helped todelay senescence,” she notes.

Richard agrees. “Up until the end of June,you couldn’t really tell the difference. But in firsthalf of July, the Revystar plots stayed green for a good ten days longer – it was a noticeable

difference. What’s more, the plants were greendown to leaves four and five, while in the farmstandard plots, these had senesced.

“It was similar to the greening effect we’dseen in the Teagasc trials during a trip last summer to Ireland, but those plots had high levels of septoria. The difference with us is thatour extended GLA wasn’t down to disease – I’ve never seen that effect before.”

Susie explains that maintaining a high proportion of the upper leaves green for as longas possible is key to realising a high yield.

“But the only disease observed when weassessed the crop in July was septoria, presentat very low levels up to the flag leaf. There wereno significant differences between treatments indisease severity or GLA from the July tissueassessment.”

These did become apparent at harvest,however. “We excluded the headland and combine runs containing wheelings, whichadjusted the yield in the farm standard treatment area to 13.89t/ha,” she reports.

“The modelled effect of the BASF treatmentwas to increase yield by 0.99t/ha, relative to thefarm standard, which is a statistically significantdifference. In this trial a yield difference of only0.44t/ha was needed for statistical significanceat the 90% confidence level.”

It was a result noticed during harvest,observes Richard. “You couldn’t really see the

difference between tramlines, but when the combine went through, it filled up the tank fasterin the Revystar strips, so we knew these wouldperform better.”

The YEN analysis suggests there was anextended grain-fill period. “It looks as though thecrop yield was somewhat constrained by a relatively low ear population, which is set early in the year, so that’s something to look ataddressing in future. But the crop fared well during grain fill, and the higher yield from theRevystar plots suggests that’s where the newchemistry really helped,” notes Richard.

“But we mustn’t overuse Revystar, or resistantpopulations will build. So I think the best timingis at T1 as the early protection will put the cropin a good place. Then we’d only need to use theproduct twice if the season really turned againstus,” he concludes.

The trials, with the Revystar tramlines markedwith arrows, were assessed using ADAS’Agronomics tool which delivers statisticalconfidence to on-farm trials.

From mid-July, the NDVI appeared slightlyhigher in the BASF tramlines, suggesting thatthe Revystar helped to delay senescence.

26 Feb 14 May 16 July

Revystar XE trials provide 1t/ha extra yield and valuable insight

2019 Real Results trials - Stevens Farm, Hawkhurst, Kent

BASF Farm Approach

T0 (28 Mar) CTL (1 l/ha)

T1 (01 May) Revystar XE (1 l/ha) Ascra (0.8 l/ha)

T2 (21 May) Revystar XE (1.25 l/ha) Elatus Era (0.8 l/ha)

T3 (06 June) Firefly 155 (0.75 l/ha) + tebuconazole (0.3 l/ha)

Results

Yield (t/ha) 14.88 13.89

Variety – KWS Lili @375 seeds/m2 drilled on 17 Sept; Previous crop – beans; In the Real Results trial,the yield shown is for the treatment strips only, excluding wheelings and calculated using ADASAgronomics.Revystar XE contains fluxapyroxad+ mefentrifluconazole; Ascra – bixafen+ fluopyram+ prothioconazole (PTZ); CTL – chlorothalonil;

Adexar – fluxapyroxad+ epoxiconazole; Librax – fluxapyroxad+ metconazole; Elatus Era – benzovindiflupyr+ prothioconazole; Firefly

155 – fluoxastrobin+ prothioconazole; GLA – green leaf area

Real Results Pioneers


grain analysis suggests it might be lacking.But it does help us make year-on-year refinements and monitor the incremental benefits these bring.”

So where did that barn-busting OSR yieldcome from? “We weren’t expecting it, to behonest. Firstly, it’s a good field on Grade 2Ragstone series, free-draining heavy siltyclay. It’s previously been let to a dairy farmerin a maize, stubble turnips and grass rotation, and this was the field’s first year in OSR.

“Secondly, the sunlight levels just wentbonkers over the season. I noticed this especially in June which would have beenwhen the crop filled the pods. What we managed to achieve was to set the crop upright so it made the most of it.”

That starts with the crop’s establishment.For around seven years, Richard’s run a controlled traffic farming (CTF) system thatputs a 6.5m Väderstad Carrier with cross-cutter discs through just the top 5-10mm toencourage a chit of grassweeds. After spraying off the green cover, this is followedby a 6m Sumo DTS with Dutch coulters thatputs the seed in 33cm bands.

“We leave the crop residues –– soil organic matter and structure have beensteadily improving, along with the yields,since we switched to this strip-tillage system. The DTS puts the seed in a narrowchannel tilled in front of the coulters. For ourheavy soils that drainage channel is key –– it mineralises the nitrogen, you get a goodroot structure and it allows the crop to getaway in the spring. With the OSR, we then follow up about a week later with some DAP.”

Quite controversially, he sows the OSR latewith a high seed rate. “Up until 5-6 years ago,we were sowing hybrids in mid-Aug, aimingfor 20 plants/m2, but found it a bit of a lotteryand often had to re-drill much of the area atthe start of Sept. So we switched strategy ––in autumn 2018, the crop was drilled withconventional Campus at 90 seed/m2 in mid-Sept, looking for 60 plants/m2.

High solar radiation“We didn’t get the large tree-like plants somegrowers aim for, but did achieve a nice, evencanopy that was knee-high by Christmas. It allwent into flower at an even timing in spring,coming out of flower about 3.5-4 weeks later.With a crop dominated by a main raceme, ithad a fine structure during its long pod-fillingperiod, so clearly made best use of the highsolar radiation,” reasons Richard.

Although he hasn’t been aiming for theOilseed YEN top slot, Richard’s crops havemoved steadily up the rankings towards last

year’s big success. Could this year’s result with Revystar point the way towards top-yielding wheat crops?

“The answers to higher yields don’t comeout of a can these days,” he says. “We’reaiming for a healthy start for our wheat cropsso we’re not firefighting through the rest ofthe season. I believe that’s also the best wayto look after the chemistry.”

That starts with the soil, continuesRichard. “We’re not going to be able to growbig crops on unhealthy soils, and our CTFsystem is really delivering the benefits here.Our involvement with YEN and with RealResults is helping us develop a truly sustainable farming system and identifypoints where we can give the crop a helping hand –– it’s those small changes that add up.” n

A low ear population in the Revystar plots wasmore than offset by an increase in grains/m2,suggesting that’s where the new chemistry reallyhelped.

Richard Budd (right) farms with his father David and joined Real Results tooptimise the inputs to get the best output.

Source: ADAS, 2019.

Performance in the real world – How Revystar XE performedagainst farm standard programmes

s

Imagine if you could scan a QR code on apacket of oats which brought up an appthat allowed you to trace the product rightback to the farm of origin so you couldensure they were gluten-free.

It’s a project involving a number of growers in Aberdeenshire, including AndrewBooth of Savock Farms, near Ellon, who aredeveloping systems to put more trust andintegrity into the food industry. It’s built onblockchain, a tamperproof system of digitallyfiling and preserving a list of records. As well as developing a farmer-owned oat-processing plant, they’ve receivedalmost £100,000 of funding from the ScottishGovernment Knowledge Transfer andInnovation Fund to pioneer the technology.

“If a product’s gluten-free, there are verystrict measures everyone, including growers,must follow to avoid contamination,” explainsAndrew. “This project puts in place a system

that will not only provide that reassurance tothe consumer, but also digitises the journey.It’s a much wider project potentially, whichcould have huge benefits for the whole graintrade.”

Savock Farms extends over 1500ha, withspring and winter oats grown alongside winter wheat, oilseed rape and spring barley,while rye and grass are grown for an ADplant. A keen advocate of digital systems infarming, he’s used various precision farmingtechniques for more than 15 years. “Themost progressive step we’ve taken on thisjourney is to adopt variable-rate drilling. Allcrops are sown in this way, including grass,”he says.

On-farm trialsAlongside this, he’s been running on-farm trials. “I first started doing them as an AHDBMonitor farmer, and now carry out a numberof field trials on the farm for our own benefitas well as for other companies. We’remembers of Scottish Agronomy who have awealth of trials and skills so it’s good to takethat small-plot data and turn it into a field trial to gain your own information. I’m alsogrowing crops, such as rye, grass and oats,on which there’s limited trials information.”

Last season was Andrew’s first withBASF’s Real Results. Local BASF agronomymanager Scott Milne suggested he try outRevystar XE against his own standard,based on prothioconazole with one application of boscalid at the T1 timing, withthe trial facilitated by Hutchinsons.

“There wasn’t a huge disease pressure

last season, but I noticed the crop treatedwith the BASF programme held on to its flagleaf for a good couple of weeks later thanthe farm standard plots. I remember raisinga concern that they’d never senesce enoughfor us to put the combine through.

“The difference came at harvest –– yieldswere generally unusually high and ourwheats brought in 10.5t/ha on average,which is 1.5-2t/ha above our budget. TheRevystar-treated areas yielded comfortablyabove this, demonstrating a clear benefitfrom the new chemistry.”

This season, Andrew’s keen to useRevystar in conjunction with xarvio FieldManager, the new digital farming packagefrom BASF (see panel on p22). “The challenge will be managing the amount of data we now receive across various platforms and making sure it beds in withour current system without overloading the

It’ll become an invaluable way to

prioritise and time varioustreatments when we

haven’t got the comfort blanket CTL provides.”

“

Andrew Booth aims to put in place a system thatwill not only provide reassurance on gluten-freeoats, but also digitises the journey.


Data drives disease decisions

There’s already a wealth of information on how best

to use Revystar XE, but how do you make sense of it onyour own farm? CPM asks

two growers with experienceof digital platforms and finds

out how xarvio Field Manager will fit in.


FeaturesDigital Direction


on-farm team,” he says.“But everything we do is customer-

focused. As we get closer to the end user, I want to show that we’re not just blanket-spraying crops, that there’s thoughtand consideration given to every application.We need tools like xarvio that can providethis reassurance, and I believe it’ll becomean essential part of retaining the chemistrywe currently have.”

Digital insightAndrew Williamson is a grower who likes to delve behind the details of any farmingprogression that comes along. He’s developed a suite of precision farming toolsto help manage considerable variability hehas over the 320ha he farms on land thatundulates between 100-200m above sealevel, based at Upper Overton Farm nearBridgnorth, Shrops.

“Farmers fall into two camps when itcomes to digital farming,” he says. “Thereare those who employ a specialist or hire ina service to help them make sense of it, and there are those who take the job onthemselves. I’m interested in it and I believe I benefit from the understanding this brings.”

So he’ll bring in weed maps he’s generated from various sources, for example, and create layers withinGatekeeper, his crop recording and mapping software, that will then tie with otherlayers to produce variable-rate seed plans.“There are packages that can do that foryou, but I get to tailor the results how I wantthem and get to understand the value of thedata I have.”

Andrew brings in the same level of analysis when it comes to trying new practices on his crops. A keen advocate of on-farm trials, he’s been involved withBASF’s Real Results since the start and gotthe first glimpse of Revystar in 2018.

“Unfortunately the trial failed –– a crop of JB Diego that was the worst on the farm anddied off early in the drought. So last year, Iwas determined to get a true picture of howthe new chemistry performs,” he says.

This time it was a crop of KWS Siskin, withRevystar applied over three tramlines to givethree replicates, with the results assessedand calculated using ADAS Agronomics. But Andrew’s been doing his own monitoringthrough the season, too. “I went to Ireland tosee the Revystar trials at Teagasc andnoticed the visual difference, so when Icame home, I set about assessing my own. You could see the difference between thetreatments –– the Revystar areas had moregreen leaf area.”

One aspect in particular he’s focused on

is the use of CTL –– this was deliberatelyomitted from both the comparison treatments, although it was used elsewhereon the farm. “There was a clear yield benefitfrom Revystar over the farm standard, but Igot a yield lift from using CTL elsewhere,although this comparison didn’t go throughthe rigorous ADAS Agronomics to give me confidence in the results,” notes Andrew.

“Revystar is a step forward and will clearlyhelp, but we’re going to be left exposedwhen we can’t use CTL, especially here inthe West where septoria pressure is higher.We mustn’t become too reliant on the newchemistry and develop other means torelieve disease pressure.”

Digital Direction

Andrew’s looking forward to using xarvioField Manager in the coming season to helpwith this. “It’s a decision management toolthat’ll help me make the right choices basedon live local data it’ll bring in. I can see it’llbecome an invaluable way to prioritise andtime various treatments when we haven’t gotthe comfort blanket CTL provides.

“But I hope I’ll be able to delve beneaththe surface, too, and bring in other data thatwill help inform those decisions with xarvio.Like anything, you’ll get as much out of a system as you put into it. That’s especiallytrue of data and in my experience manyfarmers are too precious about hanging on to their data, to their own detriment.” n

2019 Real Results trials

Timing BASF Farm ApproachT1 (09 May) Revystar XE (1 l/ha) + CTL (1 l/ha) Chord (1.4 l/ha) + CTL (1 l/ha)

T2 (28 May) Revystar XE (1.25 l/ha) + CTL (1 l/ha) Proline (0.6 l/ha) + CTL (1 l/ha)

Yield (t/ha) 12.19 11.14

Savock Farms, Newburgh, near Ellon, Aberdeenshire

Timing BASF Farm ApproachT1 (24 Apr) Revystar XE (1 l/ha) Aviator (1 l/ha)

T2 (20 May)) Revystar XE (1.25 l/ha) Ascra (1.24 l/ha)

Yield (t/ha) 10.17 9.97

Upper Overton Farm, Bridgnorth, Shrops

Variety: Skyscraper; T0 – CTL, T3 – Proline + tebuconazole + CTL; In this trial a yield difference of just0.28t/ha was needed for statistical significance at the 90% confidence level.

Variety: KWS Siskin; No T0 was applied, T3 – Proline + tebuconazole; In this trial a yield difference of0.26t/ha was needed for statistical significance at the 90% confidence level, so the difference betweentreatments was not statistically significant.

The yield shown is for the treatment strips only, excluding wheelings and calculated using ADAS Agronomics.Revystar XE contains fluxapyroxad+ mefentrifluconazole; CTL – chlorothalonil; Chord – boscalid+ epoxiconazole; Proline – prothioconazole; Aviator – bixafen+ prothioconazole; Ascra - bixafen+ fluopyram+ prothioconazole.

Andrew Williamson likes to delve behind the details of any farming progression that comes along,and make use of the data that comes with it.


Digital Direction

Field Manager from xarvio is a web and smartphone app-based crop production optimisation system, designed to help you makethe right decision on when and how to treatyour crops (currently wheat, barley and oilseedrape).

Due to go on commercial release in 2020,it’s been trialled across Europe, including 14on-farm development sites in the UK, and is thesecond of a suite of new tools, following thelaunch of smartphone-based xarvio Scoutinglast year.

“There are a couple of new functions we’vereleased on Scouting,” notes Louis Wells, UKsolutions and services manager at BASF.“Multiweed Detection allows you to take animage of a patch of weeds and xarvio will pickthem out and identify what they are. EmergenceAnalysis counts how many crop plants/m2 youhave. Currently it works just with sugar beet andmaize, but the plan is to widen its scope toinclude oilseed rape and cereals. These build onthe five existing tools that help you assess cropstatus, weed, pest and disease pressure simplythrough uploading images through the app.

“But Field Manager will be the big launch in2020. We’re really excited about how this willhelp growers make decisions on managing theircrops,” he says. This is presented through itsthree modules.

The three modulesField Monitor pulls satellite imagery into your dashboard during the season to give you an idea of biomass cover, and also leaf area index, based on normalized difference vegetation index (NDVI). The information is useful for in-season monitoring, such as to tell whether variable applications of seed and/or fertiliser have evened up a crop, and to relate biomass scans to yield maps.Spray Timer is a field-specific service that takes in information you enter about variety,drilling date, etc, and puts it through a cleveralgorithm that brings in local weather data and crop-growth information to advise on if,and when to spray to protect your crop most efficiently. The neat bit is that it factors in what field management tasks you’ve already performed. A traffic-light system indicates when you need to get the sprayer out, and special symbols help you prioritise jobs.The tool factors in what you’ve already used,with drop-down menus containing a comprehensive line-up of products, includinggenerics and competing brands to the BASF products.

Zone Spray makes use of the biomass maps and gives you a variable-rate application map, allowing you to adjust fungicide and/or growth regulator based on crop cover. Like Spray Timer, the module builds in information on previous applications and current disease pressure to determine rate. Safeguards within the module ensure statutory label rates and concentrations are not compromised, but with the variable application based on the fungicide input, the performance of tank-mix partners is at the user’s risk. A variable rate application tank-mix including a herbicide product for example is not recommended.“Feedback we’ve had suggests Field

Manager predicts growth stage very accuratelywith the Spray Timer module offering decisionsupport on a range of key cereal diseases. Thetool interacts at the field level giving advice onyour local situation. It even considers the protection and curativity given by your fungicide inputs. The more users who come onboard, the better it will get as the algorithmslearn as they go along,” notes Louis.

While xarvio Field Manager is an independent platform, which is powered byBASF, Revystar is set to work neatly within thesystem, he says. It’s the first major productlaunch from BASF since the development of thexarvio suite of services. The wealth of trials dataBASF holds on Revystar will be incorporated tohelp optimise user decisions within FieldManager. “We know Revystar has a relativelylong application window, for example, with plenty of data to back this up. Field Managertakes this into account and the algorithms will update automatically as new information is

made available.The team has also made progress in

ensuring Field Manager ties in seamlessly withother platforms, says Louis. “Compatibility is akey priority for us, and we’re aware it’s also akey requirement for farmers. We have a newinterface with MyJohnDeere that works wirelessly with Field Manager, and we’re connected to Agrirouter, bringing compatibilitywith the large number of services also using theplatform. Our vision is that xarvio should workseamlessly and with minimum effort, whateversystems you’re running or level of service yourequire,” he notes.

• xarvio Scouting is available free to downloadfor iOS and Android smartphones. Field Managerwill be launched later this year –– pricing information has not yet been released.

What is Field Manager?

Field Manager will takes into account the data behind Revystar’s relatively long application windowwhen making recommendations, says Louis Wells.

Spray Timer advises on if, and when to spray,factoring in what field management tasks you’vealready performed.

Last month I bought a new carfor the very first time. Once itwas home it just sat in theyard, looking pristine and,frankly, too clean and shiny totake to the roads and get covered with grime.

This was an entirely unexpected reaction. I’m not acar-proud person, to the pointthat generally it will only ever geta wash if it goes into the garage,but even the thought of leavingit in the supermarket car parkwas too risky to contemplate.But a few weeks on and the car has become what it wasintended to be and it’s ‘situationnormal’ –– there are mud splatters on the paintwork andfood in the house once again.

I’m feeling the same wayabout Revysol. A brand-newazole fungicide that rewinds theclock and works as well asazoles used to, that’s exciting.But at the same time, I’d almostrather it stayed firmly nestled itsbox where it can come to noharm. The one lesson we’velearned about azole chemistry is that Revysol will most likelynever be as good again after it’sbeen widely used for a number

of years. Or will it bethe one to buck thetrend?

There’s a buzz of excitement

emanating from BASFHQ about the launch of their

new Revysol-containing product,Revystar XE, and rightly so. It’sbeen an amazing achievementto breathe new life into a groupof chemistry which had beendeemed on its last legs. In reality the azoles have had badpress. They may have suffered ahuge decline in their curativeperformance, but in the fieldazole protective performancehas been hanging on and stilldelivering a useful contributionto septoria control –– albeit lessthan they used to. The azoleshave been remarkably resilientgiven the exposure they’ve had,with a decline happening slowlyover a relatively long period of time.

The smart money would probably go on the septoriapathogen finding a way of stopping this super-flexibleazole from binding to its targetsite. But the truth is no one reallyknows whether this will happenand, if it does, then just howquickly is also a big unknown.Our already highly-adapted septoria population is a very different environment to the oneany previous azole has everbeen launched in to. Has thepathogen evolved as far as itcan go already, or will it be ableto evolve a nifty new mutationthat can reduce Revysol’s efficacy without damaging itsown ability to thrive? It’s going tobe fascinating to see whetherseptoria can ultimately rise tothis new Revysol challenge.

What we do know is that taking every measure to stack

Lessons learnedbode well forRevysol

Based in Ludlow, Shrops,Lucy de la Pasture hasworked as an agronomist,while among the Twitterati,she’s @[email protected]

the odds in Revysol’s favour isthe wise approach to prolongingthe useful life of this badly needed new fungicide. Theolder azoles have provided auseful opportunity to learn abouthow to slow the development ofresistance and this has been putto good use to help stabilise theSDHIs once they showed earlysigns of weakening. The factthat Revysol is only available informulation with BASF’s SDHI,fluxapyroxad, as Revystar bears testimony to the fact thatcombining groups of chemistryhas been proven to protect fungicide performance.

We also know that the doserate and number of applicationsof an azole affect the selectionpressure that septoriapathogens are under. MotherNature has already done her bit this autumn/winter to limit the new active’s exposure in the coming season, with amuch-reduced area of winterwheat in the ground which willhave a big impact on fungicideuse. As far as dose rate is

concerned, there’s still more anelement of judgement than science involved in determiningfield rates of fungicide.

In time, science will continueto help us optimise fungicideuse in the field, from both thegrower margin and resistancemanagement perspectives. But right now, we have a newazole with some very interesting attributes to celebrate and itsarrival is timely. BASFs olderazole epoxiconazole remainsunder threat from the regulatorsand, should it go, the last azoles standing will welcome the assistance of a younger, moreagile member of the family in dealing with a septoria population that has a lot morefight than it used to.


Revystar RoadshowsBASF is joining forces with the farming community to run aseries of agronomy-focused roadshows from late Jan until earlyMarch 2020, focusing on farmer dominated business insightsand the launch of new cereal fungicide, Revystar XE.

The dates and venues for the events are:l 29 Jan - Newbury Racecourse with Robin Aird l 4 Feb - Exeter Rugby Club with Mike Hambly l 6 Feb - Cosford RAF Museum, Shropshire with

Andrew Williamson l 10 Feb - Beeswax Dyson, Lincs with Ben Abell l 12 Feb - Hop Farm, Maidstone with Richard Budd l 14 Feb - Ravenwood Hall, Bury St Edmunds with Toby

Hogsbjerg and Hannah Darby l 3 March - York Racecourse with Pat Thornton l 5 March - Murrayfield Stadium, Edinburgh with

Andrew BoothTo sign up, go to basfrealresults.co.uk/revylution

Documents

In this issue - cpm-magazine.co.uk · number, date of birth and postcode to [email protected] Opinion Forward - Introduction from this issue’s sponsor. Talking Tilth - A