Why does Yellow Rust resistance ‘break down’?

When the pathogen spores land on the wheat plant and begin to infect, it releases hundreds of compounds as part of the infection process. The plant ‘recognises’ this and deploys its defence response i.e. resistance. As the pathogen replicates, random errors occur when copying its genetic material; it just takes an error in the code of the compound that is recognised by the plant, and the plant no longer recognises the pathogen and so will not initiate the resistance response. Also, with the ever-changing Yellow Rust pathogen population, new pathotypes are appearing, and often avoid the plant’s defence response.

What are plant breeders doing to develop resistant varieties?

We are constantly looking for novel resistance genes which we can breed into our new varieties in combinations. Using molecular marker technology, we can combine multiple resistance genes in a single variety. By having more than one resistance gene, we reduce the risk of the resistant variety becoming susceptible.

Are all resistance genes equal?

No. Some resistance genes provide juvenile resistance, whilst others work in adult plants. Some provide ‘full resistance’, whilst others reduce the severity of the Yellow Rust symptoms. It’s worth noting that it costs the plant to deploy its resistance response, and this can often be seen as a reduction in yield. Our job as breeders, is to find effective resistance gene combinations that do not come with negative side effects.

This can be attributed to the variety’s good agronomic characteristics of short straw, great disease resistance and good grain quality.

LG Mountain offers a significant step forward in yield for 2-row barley varieties.

It sits at the top of the AHDB 2020/21 Recommended List, with a UK yield of 104%, performing particularly well in the east and north (105%), says Ron Granger, Arable Technical Manager.

He points out that these high yields have been consistent over seasons and regions from 2016 to 2019, in fungicide treated AHDB RL trials.

“This resilience and robustness in yield, is a really important attribute in a variety, as growers know that whatever the season throws at them, it is able to cope.”

LG Mountain is also the highest yielding 2-row in both light and heavy soils, showing its flexibility within the rotation. It is an earlier maturing variety at -1, and benefits from a good all-round disease resistance profile, including BaYMV resistance.

Limagrain trials have shown that LG Mountain moves quicker in the spring than its stable mate, LG Flynn.

Limagrain Agronomy Trials

Agronomy work carried out by Limagrain, looking at ‘seed rate vs PGR vs fungicide performance’, confirms that there is little difference in yield when LG Mountain is sown at seed rates of 300 seeds/m2 or 400 seeds/m2, yielding around 11.5 t/ha in each scenario.

LG Mountain is a shorter variety, and the Limagrain trials data suggests that yield potential can be compromised if high rate PGR programmes are used, compared to the taller strawed varieties. Limagrain still recommends that a good PGR programme is used to ensure straw strength and reduce brackling, especially in a high yield situation such as on heavier, fertile soil types.

LG Mountain responds very well to both low and high input fungicide programmes, and again, programmes should be targetted regarding the situation in hand.

The variety has good grain quality attributes, with a very good specific weight of 69.1, combined with good grain screening percentage, similar to KWS Glacier; an important feature in a 2-row winter barley.

David Waite, regional seed manager with Frontier, sees one of the key attributes of LG Mountain being its consistent set of yield scores over the past four years – maintaining the top yield for the AHDB North region, with one of the better specific weight scores.

He said, “Along with these consistent yields, a strong (7) for standing with average straw length, provides growers with a sound agronomic package.”

Samson Stubble Turnip

Give the arable crop rotation a break and sow a forage crop this autumn, to help achieve better weed control and boost home grown feed supplies. Mixed cereal and livestock units are encouraged to think about growing forages on some of their arable land, as this will help weed control by breaking the life cycles of some damaging weeds and diseases.

Forage crops – and any grazing livestock – add organic matter to the soils, which is especially valuable in nutrient depleted soils. Soil structure and condition warrants attention on many arable units, and rotations that include forage crops are more sustainable in the long run.

Forage crops, such as; fast-growing brassica and root crops, and short-term grass leys, can be sown post-harvest to give a much-needed break in the cereal rotation, as well as providing a valuable feed crop.

Unicorn Rape Kale Hybrid

Roots and brassicas can be grazed-off ahead of a spring drilled cereal crop, or ahead of a grass reseed. Leaving a grass ley down for two to three years will also help break the blackgrass cycle.

There are plenty of high feed value varieties to choose, that can improve livestock growth rates and performance.

Our recommendations are:

Samson stubble turnip – for grazing October onwards
Unicorn rape-kale hybrid – high protein leafy forage
Meatmaker brassica mixture – contains stubble turnips and forage rape for later use.

Steve Cook

“We have the right climate here for top quality wheats; the temperatures are warm, and the crops mature more quickly. On these chalky soils, the variety yields around 9-10t/ha,” he says.

Steve emphasises that margins from commercial yields are key to grower profitability, rather than going for out-and-out yield.

“Having the confidence to supply customers with a consistent quality Grade 1 bread-making wheat, is crucial to many growers.”

When Crusoe was launched in 2012, it set the standard for a new kind of milling wheat, that offered very high yields with excellent grain quality, combining a stable high Hagberg and high specific weight, in addition to very good agronomic characteristics – notes Ron Granger, Limagrain UK’s arable technical manager.

“Eight years later, and Crusoe is still well-placed in the 2020/21 AHDB RL table for Group 1 wheats, and is one of only two GP1 bread wheats approved for export – thanks to its proven, exceptional bread-making quality.”

Steve Cook agrees: “Choosing a variety, such as Crusoe, whose Hagberg Falling Number (HFN) holds up when the weather at harvest is less than ideal – and we often get rain in August, can mean the difference between having a saleable wheat or losing it.”

Agronomic strategy and attention to detail is important for getting the most from the crop.

“Decisions on fertiliser applications are based on the local conditions, and in this area, we do not have deep soils, so there is no huge reservoir of nutrients to tap into; the chalk is just calcium carbonate and some water.”

Steve typically recommends between 240-260kg/ha of N, tending not to use late foliar N – recognising that some millers do have a preference.

The variety’s general agronomy package is good, and managing its susceptibility to brown rust is not difficult and costs no more than for other milling wheats, continues Steve.

His fungicide strategy includes an application of Elatus Plus (benzovindiflupyr) at T2, with tebuconazole following at T3 for fusarium, and he finds this also controls any brown rust in the crop.

Growing a variety with different options for market can be important too, he explains.

The area used to have two local mills for bread-quality flour – one in Andover, and the other in Southampton, but the Southampton one has recently been closed, leaving just one. There are, however, other options and potential markets open for Crusoe growers.

“As it is more difficult to grow wheats with the required quality consistency further north, they are often shipped out of south coast ports, to other areas in the UK.

“Crusoe is one of the very few Group 1 varieties that has approval for export, and it has a really good specific weight, which is really important for when you are shipping wheat.”

“Growers really like Crusoe because they know they have a reliable protein level and HFN, so they know they can always find a market for their product.”

“It is the number one choice for grain quality – and the other factors we can manage.”

What the millers look for

With tight specifications for Group 1 wheat being demanded, achieving them year-in, year-out, can be challenging for growers.

A flour milled from a Group 1 wheat is usually going to be used to produce bread and risen dough products, such as buns and rolls. The typical specification for a Group 1 wheat is 13.0 percent protein, 76.0kg/hl specific weight, and 250’s HFN.

Each characteristic is important for different reasons, says Joe Brennan of the National Association of British and Irish Flour Millers (nabim).

While protein is needed for gluten quality and functionality, a high specific weight is necessary for protein quality and a good extraction rate, and a high HFN is needed to avoid quality issues with doughs, explains Joe, who looks after wheat and supply chain issues, and environmental issues.

However, he points out, one of the challenges millers can encounter is that not all protein is the same.

“The percentage we use is an general indicator of the quantity of protein, but it does not report the quality. When grain arrives at a mill, you cannot quickly test the protein quality and so we have to  test the quantity – however, you can have a crop with 13.0 percent protein that has poor gluten quality.”

Joe notes that recent claims and counter-claims regarding protein quality derived from late applied foliar N, are currently being investigated as part of an Agriculture and Horticulture Development Board (AHDB) funded research project, aiming to update N and S fertiliser recommendations for milling wheat.

Consistency from a variety is really important for millers and processors, he emphasises.

“Mills produce flour that is used to produce food at an industrial scale, and our customers expect consistent quality every time.”

“Having varieties that perform predictably across regions and seasons, helps millers achieve this.”

“Crusoe consistently demonstrates good protein content and quality as demanded for a Group 1 wheat. It also produces a breadcrumb structure that is fine and notably white.”

“Given Crusoe’s consistently good baking quality, it continues to be a popular variety with millers.”

Allied Mills and the Allied Technical Centre say that Crusoe has the milling properties they look for in a wheat variety, producing a high extraction rate and excellent flour colour. Dough strength and baking performance are both consistently good.

“Crusoe has been an important variety for Allied Mills over many years, and we continue to value its reliability.”

Nick Wallace, Scottish Regional Manager, Nickerson Seeds

When making decisions on what OSR variety to grow, gross output figures are key for Mr McLean but this must be backed up with strong agronomic characteristics that suit his system and region, he notes.

Paul works closely with Nick Wallace of Nickerson seeds, the retail arm of breeders Limagrain UK, as he is familiar with the characteristics of his farm which is hilly and with a range of soil types ranging from loam to heavy clay at the bottom of the hill.

Talking to Nick and looking at the AHDB Recommended 2020 / 2021 List for the northern region, he decided to try a small area of the conventional Aspire.

“Aspire is a very high yielding conventional variety and is the only AHDB recommended conventional variety with TuYV resistance. Recommended last year, Aspire offers very high gross output for the east/west and north regions – as was proven in harvest 2019 with a UK gross output of 106%,” says Nick Wallace.

“It is short and stiff-stemmed and therefore easier to manage, add to this, its TuYV resistance, scott strong disease profile and the opportunity to early drill early, this agronomic package makes it a very farmer friendly variety.”

Nick reckons a lot of growers will be looking to target that initial sowing window this coming season as they will be looking back over the past few years and will see the early drilling slot is often the go-to, to avoid catchy weather patterns.

The rotation at Keillor Farm includes spring barley, wheat and potatoes, with oilseed rape being included after a five year gap. Agronomy is provided by East of Scotland farmers who also do all of the spraying.

“All our inputs are tailored year-on-year, according to the threats and stresses the crops are under, and decisions are made accordingly. Taking this approach also allows us to maximise our work as contract farmers, Paul explains.”

“Oilseed rape usually goes in after the spring barley. Our cultivations focus around ploughing, drilling, and then rolling. We use a Lemken Solitaire drill set at 30cm, which produces a quality seed bed for crops to emerge evenly.”

Paul McLean of Keillor Farm, Coupar Angus

“We drilled 19ha of Aspire on 3 September 2019 at approximately 75 seeds/m2 as we find that the extra room allows bigger, stronger plants to develop.”

Keillor farm is located in a nitrogen vulnerable zone (NVZ), so there are limits to fertiliser applications, so Paul applies it in splits.

“We broadcast after sowing, and then towards the end of February or the beginning of March, we apply three splits of blended granular fertiliser (Yara Extran S) which helps us get the most from the crop.”

“This year we broadcasted 300kg of 10.18.24 + 9S just after drilling on the 14th September. This was followed up in the spring with 3 splits of Yara Extra 14-9-19. The final application goes on as late as possible, without damaging the OSR flower, and this year it went on 29th April.”

“We have found that applying sulphur has turned out to be crucial to quality, the one year it was not applied, there was a real difference.”

“Despite the horrendously wet winter, we have an absolutely bumper crop coming in from the Aspire. It showed really strong spring vigour, and flowered earlier than any of the other rape varieties on the farm.”

“We hope to make 4.9t/ha with this crop, which will be a slightly higher yield to what we have ever achieved. Limagrain varieties tend to always do really well on our land and this coming season we plan to continue with Aspire after spring barley and will try the new conventional variety, Acacia, to sow after wheat.”

Farm Facts:
Total farm area: 200ha
Soil: Loam to heavy clay
Rotation: Spring barley, wheat, potatoes, oilseed rape one year in five

Craig Norrie of Banchory Farm

This will be Craig’s third entry into YEN; last year his Zulu crop recorded a total yield of 13.1t/ha, achieving 77% of the grain’s potential yield.

Participants into the YEN receive a full set of metrics on the performance of the entrant’s crop, which they can then compare with other YEN crop entries. Craig finds this a very valuable exercise and also an opportunity to discuss learnings with other growers.

The reports also help growers optimise their grain quality, for example Craig identified from the grain analysis in the first year’s report that there was not enough sulphur in the fertiliser, which he then adjusted last year.

He also highlights that because of the competition, he has a greater appreciation of the importance of organic matter (OM) in the soil. Analysis shows his farm has a good level of organic matter in its soils, which he attributes to 20 years of following a strong rotation and his cultivation strategy. He min-tills two years in a row for winter oilseed rape, and follows by first wheat, and then ploughs for spring barley.

“When we started to follow this approach, we were not thinking of organic matter, so it was interesting to learn that we are helping our land, and this gave us a real confidence boost.”

YEN 2020

LG Spotlight stood out in Craig’s on-farm trials last year. “Excellent yields of 11.32t/ha, superb grain quality and Hagberg from the large plots, highlighted LG Spotlight as a serious contender, “explains Craig.

He picks the top three varieties grown in his trials, growing 15-20ha of each, and the following year, the highest yielding one is grown across the whole of the farm.

On this basis, he drilled 15ha of LG Spotlight between the 28-30^th October, into a field of medium to heavy loam, using a seed rate of 200kg/ha. “It was really wet by then, and my agronomist wasn’t sure if I should go ahead and drill, but we persevered, and the LG Spotlight didn’t let us down. Its vigour and ability to get away was astounding – a very valuable attribute, when conditions were as challenging as they were last autumn,” he says.

Craig has been using variable rate P, K and lime since 2008 and, as part of his normal agronomy strategy, the LG Spotlight received 1750 litres/ha of liquid N in three applications.

To push his crop as hard as possible for the competition, he plans to give it a final dose of foliar spray of N.

The first fungicidal spray was applied at GS31; decisions for the remainder of the spray programme will be made according to the season and disease pressure.

With a good start behind it, the wheat is now looking well with little disease, he reports.

“There’s no doubt LG Spotlight has set a new standard for soft wheat grain quality, its excellent grain quality with a specific weight of 77.9kg/hl, and Hagberg Falling Number (HFN) of 288, whilst also producing high yields, are key to the growing popularity of the variety,” says Douglas Bonn of Nickerson Seeds.

It is this grain characteristic that makes it popular with both growers and the distilling markets, he adds.

Ron Granger, Arable Technical Manager

Ron Granger, Limagrain’s arable technical manager confirms this; “LG Spotlight has similar physical grain quality characteristics as Group 1 & 2 quality wheats; an unusual combination in a soft wheat.”

He points out that LG Spotlight bucks the trend that soft wheats tend to have a HFN in the low 200’s or below; LG Spotlight with a HFN of 288, is well ahead, and is the highest available of all the soft wheats on the AHDB 2020/21 Recommended List.

“This, combined with the fact it is one of the best varieties available for sprouting resistance on the AHDB RL 2020/21, makes LG Spotlight very different from the rest – giving growers valuable grain characteristics for allowing harvesting flexibility and yield security.”

Craig agrees, pointing out that in a ‘catchy’ season when you have to decide which field to harvest first, the stability of the quality in LG Spotlight means that you can keep it on hold for a few days, which helps spread your risk and workload.

Douglas highlights that one of the grandparents of LG Spotlight is the firm favourite, Istabraq, and it would appear some of the grain quality attributes have been passed down.

Similar to Istabraq, LG Spotlight performs well in a second wheat position. This position in the rotation requires a variety to have exceptional grain quality, and the ability to perform under less than ideal conditions, he says.

Added feed value, improved lamb performance and lower running costs are driving the popularity of multi-species leys.

Lambs reared on these carefully formulated mixtures of grass, legume and herb species have been shown to reach finishing weights significantly earlier than those grazing traditional pastures with white clover.

They were also found to carry a lower worm burden and had lower requirement for anthelmintic treatments.

Sown in spring or autumn, multi-species mixtures generally include three or more grass species, a mix of protein-rich legumes that fix nitrogen and deep-rooted herbs that provide drought tolerance and the potential to boost the crop’s mineral content.

Yields from these good multi-species mixtures are generally higher than the sum of the individual components. This is known as the diversity effect.

Trials have shown that the dry matter yield of some multi-species mixtures receiving 90kg N/ha can be similar to, and in some cases better than, perennial ryegrass swards receiving 250kg N/ha. They also offer the potential to dispense with applied nitrogen, making them an option for organic growers.

Limagrain offers scientifically formulated multi-species mixtures in its Sinclair McGill range.

Lambtastic includes high performing ryegrass cultivars combined with Timothy to ensure it gets off to a sprint start in spring and remains productive well into autumn. Forage chicory and plantain combined with the attributes of a proven white clover blend are all known to promote lamb performance.

CastleHerb combines 40% intermediate and late perennial ryegrasses species, with 30% each of legumes and herbs. Matrix-enhanced ryegrass is included. This provides a crop with an extended grazing season and very rapid regrowth. CastleHerb can, in some cases, qualify for grant aid under the Countryside Stewardship Scheme.

These multi-species mixtures also make a significant contribution to the environment by increasing invertebrate numbers, including earthworm populations, and encouraging wildlife.

Turnips yellows virus (TuYV) is transmitted by aphids and it is believed that 70% of the most common aphid, peach potato aphids (Myzus persicae) carry it. Work carried out at Brooms Barn a decade ago, showed a 30% yield penalty where levels of the virus were high and infection occurred early in the crop’s life.

Recent data from Brooms Barn confirms just how high recent aphid pressure is; the Brooms Barn long term average of accumulated catches of Myzus persicae up to 21st of June normally runs to just under 500 aphids caught in their traps. For 2020 this was running at 4400, nearly a tenfold increase. Some plants that were being monitored had 50-100 aphids per plant.

AHDB aphids news tells a very similar story; in the report until the end of June, Alex Greenslade of the Rothamsted Insect survey team, reported that average air temperatures continued to exceed the long-term average. “Coinciding with this, the total cereal aphid numbers increased to around 120% of the last period,” he said.

“Sugar beet is already showing the consequences of this high aphid pressure with many crops exhibiting Virus Yellows symptoms. As aphids start flying in the spring they tend to head for sugar beet first, and then as oilseed rape crops are drilled in the autumn they move across into these,” says Dr Vasilis Gegas, EU portfolio manager for oilseed rape at Limagrain.

“The link between high numbers of aphids in the autumn and corresponding levels of infection is clear.”

“Infection usually occurs in September to October when aphids are still flying; the earlier a crop is infected, the more severe the symptoms tend to be with harsher yield penalty as the plants have less seeds/pods .”

“Early drilled crops that are more open, corresponding with mild autumnal conditions, are at the highest risk,” he adds.

“As control of aphids has become increasingly difficult, so numbers have increased, with a subsequent build up of TuYV inoculum in the environment.”

“Once an aphid is infected, it is infected for life – if an uninfected aphid feeds on an infected plant, the aphid becomes infected and so the cycle continues.”

“Infected plants produce fewer side branches, pods, and seeds per pod. It’s confined to the phloem, so potentially robs the plant of resources that would be fed to the roots.

“But you often don’t see severe symptoms, which is why TuYV often goes undetected. Today’s challenge is that it has become increasingly difficult to control early infection with the loss of neonicotinoid seed treatments, and getting the timings right for spray’s is very difficult.”

“Genetic resistance is by far the best way forward.”

What are TuYV levels now?

Yellowing as a result of TuYV

Since 2016, Limagrain UK along with industry partners – Agrii, Openfield and the AICC – have been monitoring levels of TuYV in crops across the UK. It’s part of a programme carried out across Europe, with leaf samples taken both in the spring and autumn and tested using the standard Elisa test.

“We’ve mapped the incidence of TuYV from the UK to Ukraine and seen it build over the years,” notes Vasilis. “We’re getting to a situation where in some locations 100% of crops carry the virus. It’s now endemic across Europe, and no longer confined to hotspots.”

Sampling is carried out twice during the growing season, with an initial small-scale survey conducted in Oct-Nov, followed by extensive testing carried out in early spring. “The last couple of seasons we have found very high levels of infection in UK crops in the autumn, which wasn’t the case before.”

“TuYV incidence reached its highest level ever last season, with an average of 84% of non-TuYV resistant UK crops infected in early spring 2019. Almost all sites had an infection rate between 81-100%.”

While incidence was highest in East Anglia and south east England, sites in Scotland and the South West now show high levels of infection. “Four years ago we wouldn’t have seen high levels in the North. But last year we saw 70-75% infection of OSR in Perth and 50-54% in Aberdeen,” he points out.

CHART: TuYV incidence across Europe – 2019

Source: Internal analysis, Limagrain Europe Laboratory, 2019; TuYV incidence in non-resistant varieties per country, 430 locations.

So what role can genetics play?

The value of genetic resistance to TuYV has been well proven since Limagrain launched its first variety Amalie back in 1995. Initially the genetic resistance came with a yield lag, but innovative breeding has overcome this and today, the highest yielding varieties on the AHDB Recommended List all carry TuYV resistance.

This was confirmed in 2019 trials results conducted by the Association of Independent Crop Consultants (AICC) in West Wittering, showed that there was around a 0.4-0.5t/ha yield advantage from varieties with TuYV resistance against those with none.

“Limagrain’s conventional Aspire, performed very well yielding 6.7t/ha; that’s a significant yield jump over the 6t/ha from the non-TuYV resistant variety; Campus. Aurelia was just behind, yielding 6.4t/ha,” explains Peter Cowlrick, director in CCC Agronomy Ltd, who managed the trials.

In Suffolk, the trend was the same, with TuYV resistant varieties leading the pack. Aurelia managed a top yield of 6.1t/ha, well above that of Campus at just above 5.6t/ha. Ambassador yielded just below 5.9t/ha and Aspire 5.86t/ha.

“These varieties also play an important role in IPM, as there is less reliance on insecticides which are challenging to time correctly, especially near the coast, and in a crop where the canopy has grown up well and provides its own microclimate for aphids to continue reproducing, “ says Mr Cowlrick.

“In the south-east, where the risk of TuYV infection is very high, on some farms almost 80% of the crop going into the ground this autumn will be TuYV resistant varieties. There’s such a strong argument for growing a TuYV-resistant variety, why wouldn’t you?”

Limagrain’s top yielding varieties all carry TuYV resistance:

LG Mountain has performed particularly well, at 107% of control, 6% above last season’s most popular variety KWS Orwell and 7% above the new recommended variety KWS Hawking.

LG Mountain has consistently produced these excellent yields across regions – even at some of the more challenging sites in Lincolnshire and Cambridgeshire.

“The five-year average values (2016 to 2020) provides a better representation of performance across seasons and LG Mountain has consistently produced the highest yields at 104%,” says Ron Granger, arable technical manager for breeders Limagrain UK.

“This consistency of performance is a really important attribute in a variety, as growers know that whatever the season throws at them, it is able to cope.”

“Over this time, LG Mountain has also demonstrated its ability to produce high yields on both light and heavy soils, showing its flexibility within the rotation.”

“This excellent yield resilience can be attributed to the variety’s good agronomic characteristics of short straw, good disease resistance and great grain quality,” he adds.

Agronomically, LG Mountain is an earlier maturing variety at -1, and benefits from a good all round disease resistance profile, including BaYMV resistance. The variety has good grain quality attributes with a very good specific weight of 69.1, combined with good grain screening %, similar to KWS Glacier; an important feature in a 2-row winter barley.

Agronomy Approach

Agronomy work carried out by Limagrain looking at ‘seed rate vs PGR vs fungicide performance’, confirms that there is little difference in yield when LG Mountain is sown at seed rates of 300 seeds/m² or 400 seeds/m², yielding around 11.5 t/ha in each scenario.

LG Mountain is a shorter variety, and our trials data suggests that yield potential can be compromised if high rate PGR programmes are used, compared to the taller strawed varieties, says Ron.

“We still recommend that a good PGR programme is used to ensure straw strength and reduce brackling, and especially in a high yield situation such as on heavier, fertile soil types. The variety responds very well to both low and high input fungicide programmes, and again, programmes should be targeted regarding the situation in hand.”

“LG Mountain is certainly demonstrating itself to be a very reliable variety with regards to consistency of performance – a desirable attribute for any grower considering our recent seasonal, variable erratic weather patterns.”

David Waite, regional seed manager with Frontier…

David Waite, regional seed manager with Frontier, sees one the key attributes of LG Mountain being its consistent set of yield scores over the past 4 years through to this year’s harvest – maintaining the top yield for the AHDB North region, with one of the better specific weight scores.

“Along with these consistent yields, a strong (7) for standing with average straw length, provides growers with a sound agronomic package.”

One of the key drivers in the decision to drill OSR for rapid and consistent emergence in order to avoid adult CSFB grazing is adequate moisture in the seedbed.

With the recent and forecasted unsettled weather into early August, bringing rainfall to many parts of the country, soils are wetter than they have been for a few seasons, providing the much needed opportunity for oilseed rape establishment.

“Lack of moisture in the seedbed has been a dominant factor affecting establishment in the past two seasons, as where seed was planted into dry and dusty seed beds, germination and subsequent crop emergence was slow and erratic,” says Liam Wilkinson, arable development officer for breeders Limagrain UK.

“Oilseed rape seeds harbour less energy stores than other species, so ensuring plants can establish roots quickly and that those roots then have access to moisture and nutrition is key for strong autumn establishment and vigour.”

“Current favourable soil conditions and an early harvest in some areas, will mean that many growers who have been undecided about growing oilseed rape this autumn, may now be considering putting the crop in.”

“Whilst these current conditions offer an opportunity for the crop to establish – it’s still very early to consider drilling rape. It’s worth remembering the pro’s and con’s of this drilling time as whilst early drilled crops, if well-established, can better withstand attack from adult CSFB, it makes them more vulnerable to larval damage – meaning that drilling early for flea beetle may not be the way to go,” he warns.

Liam refers to a current research project, funded by AHDB, in which Dr Sacha White (Senior research entomologist at ADAS), has analysed 1,100 sites dating back 14 years, looking at the correlations between drilling date and damage from CSFB.

“One clear trend that emerged, was that later drilled sites had markedly less larval damage.”

“In recent seasons the most severe damage to OSR crops has been caused by the CSFB larvae rather than the grazing damage by adults. Later drilling means that the crop misses the main influx of adult CSFB during migration; resulting in later egg laying with cooler temperatures, slowing development of eggs and larvae.”

“This results in lower larval numbers in the autumn and in the following spring.”

The correct varietal choice is absolutely fundamental to whichever drilling time, based on the attributes needed for that particular timing, says Liam.

“With later drilling choose varieties that can establish quickly and cope with the risks of drilling later – such as the potentially more damaging effects of phoma on smaller crops and increased risk of winter damage. “

“Plants should aim to have established a sufficiently large biomass to overwinter to aid with overall robustness and increased spring growth, which in turn can help to grow away from spring larval damage. “

High yielding hybrids such as Ambassador, Aurelia and Artemis fit the later drilled position perfectly. They have amongst the highest early vigour scores in Recommended List harvests 2019 and in Limagrain’s own internal trials, he explains.

“As trait loaded varieties, they offer genetic traits such as the RLM7 resistance gene which provides exceptional resistance to phoma (which can be more problematic in later drilled crops), with the added security of resistance to Turnip Yellows Virus and pod shatter resistance to protect against seed losses at harvest.”

However in areas where CSFB is not of as much concern and drilling conditions tend to be wetter such as in the north or west, varieties such as Aurelia, Artemis, Aardvark and Aspire, fit an early drill window perfectly. In the correct conditions these varieties will establish well and not leave too big a canopy to manage over the winter.

Remember when drilling early, to drill when seed bed conditions are right, not by calendar date.

Consider seed rates

One method growers’ have tried to mitigate for CSFB damage, is to drill at higher seed rates. Dr Sacha White (Senior research entomologist at ADAS investigated this and found that higher seed rates produced the same number of larvae per plant as there were in plots drilled at lower seed rates.

This meant that there were higher larval numbers in plots drilled at higher seed rates, potentially causing higher pressure in nearby OSR crops the following year. Also, higher seed rates can lead to overly large canopies that require management to deal with an increased risk of lodging. With vigorous varieties, seed rates should target 25-30 plants/m² and in the case of less vigorous varieties, aim for 40-45 plants/m^2.

“These are the highest oilseed rape yields we have ever achieved, and that’s taking into account some bare headland areas,” he says.

Having dropped oilseed rape from the rotation at the AHDB Monitor Farm seven years ago as it was underperforming, Mr Jones is thrilled with these harvest results, particularly as the LG Ambassador will go forward into the YEN Oilseed competition this year.

LG  Ambassador is the highest gross output hybrid variety on the current recommended list. LG Ambassador shows exceptional autumn and spring vigour and has a very good disease resistance profile. Ambassador from LG Seeds is the first 4 trait hybrid variety in the market.

Aspire is a very high yielding conventional variety and is the only AHDB recommended conventional with TuYV resistance. A very robust plant type with short stiff stems.

“The LG Ambassador was drilled slightly later on the 6^th September 2019, and we were very lucky with the crop in the autumn as we didn’t have any CSFB infestation so it got up and away, and the crops stayed clean season- long. Both varieties have TuYV (Turnip Yellows Virus) resistance and without a doubt this held yields up.”

Mr Jones believes that in dropping the plough and harrow system he used previously, for min till into stubble, the rape crops do not come through as lush and thick, and that by having fewer plants and a thinner crop that has more space and light, yields have improved.

He will be growing both varieties again next year and has already put in his seed order via his Nickerson Seeds rep, Simon House.

2019 proved to be a divided growing season for many farmers looking for maize to provide a quality foundation to winter diets. For the most part, crops got off to a good start and grew strongly, offering the prospects of both good yields and high quality.

“Things started to unravel in the autumn when the wet conditions impacted on harvest,” Mr Camplin comments. “While some crops were harvested in good conditions, a significant proportion were harvested late, resulting in poorer quality forage, reduced yields and a delay in getting maize into the diet. Indeed, some crops may never be harvested.

“The important thing now is to plan ahead and decide what changes can be made this year to ensure you hit the real objective of growing maize – producing sufficient high-quality forage to last the winter and help support cost-effective milk production. It is more important to have quality than bulk. This planning also needs to consider the legacy of the wet autumn and changes to the availability of seed dressings.”

Mr Camplin says the very wet weather will mean that soils could be slow to warm up in the spring, especially if we have a cold snap in the new year. This might make it difficult to work seedbeds down to a fine tilth and will certainly make early deeper drilling, which has been proposed as an alternative way to reduce bird damage, less of an option.

He explains that this year there will be very little seed available treated with Mesurol which has become the default bird repellent seed dressing, hence the need to consider alternatives actions.

“Mesurol has largely been replaced with Korit this year and the majority of our seed will be Korit treated. While it is an effective bird repellent, it will be important to check what your seed is treated with and to make sure your contractor knows as Korit has specific toxicity issues.

“However, for many farmers, bird repellents are probably not necessary. At our five test sites across the country, we have not treated our variety trials with Mesurol for 10 years, giving a total of over 40 trials.  In that time, we lost just two trials completely to birds, with just one other trial substantially damaged. So, it might be that in many cases birds are less of an issue and bird repellent seed treatments an insurance premium as opposed to a necessity.”

Mr Camplin believes success in 2020 will depend on variety selection, field selection and agronomy at drilling. To maximise the chance of getting the yield and quality required, he advises avoiding late fields and those at risk of water-logging in the autumn.

“Choose a field that will be warm in the spring and allow you to get on it at harvest. Work the seedbed down and only drill when soil temperatures are consistently at a minimum 8°C at the depth seed is to be sown, to get the seed germinated quickly. The aim is to get the plant to grow as quickly as possible to the two-leaf stage when bird problems are greatly reduced.

“Drilling early in cold soils could mean the seed will be slow to germinate and slow to grow away.”

He advises checking on the historic annual accumulated Ontario Heat Units for the farm and selecting varieties which will mature earlier in the autumn, increasing the probability of harvesting in good conditions.

“Go for an early variety with good early vigour to make sure they get away quickly and mature in good time. Modern breeding techniques have effectively eliminated the traditional yield penalty seen with early varieties and feed quality is typically excellent, so there is little need to gamble on later maturing options.

“Widely grown varieties like Glory and Pinnacle are both maturity class 10 or FAO 190 and are high yielding with excellent starch and ME content, while newer varieties like Trooper, Echo and Gema also produce quality forage from an early variety, reducing the risk of a difficult harvest. They all have exceptional early vigour so will get established quickly to reduce the bird risk.”

He says early vigour has also shown to be improved by using the next-generation biological seed treatment Starcover, which uses a combination of a plant extract that accelerates root development and increases root number and length, in conjunction with plant growth promoting bacteria that help improve nutrient uptake and boost early plant growth.

“In trials over several years, Starcover treated crops have had 18% more roots that untreated plants. Two weeks after drilling, treated plants were on average 5.1% higher and 15.4% higher five weeks after drilling, meaning they were capturing solar energy more efficiently sooner.

“When harvested, treated plants yielded between 3-7% more dry matter per hectare and forage was on average up to 2.6% DM higher.

“Using biological seed treatments combined with early varieties with good early vigour will help improve the prospects of a successful harvest of a high-quality feed. But the key is to plan to reduce risk when establishing maize this spring.”

Watch how Starcover works…