Cereal crops started the spring looking ‘full of promise’, at the T1 timing there was ‘all to play for’ and as T2 fungicides are rounded off, it’s a case of ‘time will tell’ as the dry weather continues. CPM reports.

I’m seeing more disease where there are sprayer overlaps than misses, which makes me think that the yellow rust has taken advantage of a stressed crop.

By Lucy de la Pasture

The one thing about farming is that no season is ever the same. Earlier this year crop development seemed more the norm compared with last spring’s slow start, but by the third week of May many wheat crops already had ears emerged and a few were even flowering.

“Crops are around two weeks ahead here, having moved through the growth stages quickly since T1s were applied. It’s been an interesting season,” says Andrew Wells, Arable Alliance agronomist and part time farm manager based in Nottinghamshire.

Although the showers trickling in from the West through the middle part of May have helped, Andrew says crops are on a knife-edge because it’s been so dry. “February was the only month this year we’ve had above average rainfall, other than that it’s been incredibly dry. If we have a hot week then it may tip the light land crops over the edge but, for now, showers are keeping crops hanging on.”

The ongoing dry weather has also had an effect on spring planted crops. “Spring barley hasn’t tillered as much as it would normally which means we’ll be short on ear numbers, and number of ears equates to yield,” he says.

But all isn’t doom and gloom because grain prices are good, he adds. “I’m not keen on forward selling any of my own grain as I think the weather will still play games with us and influence the market. Europe is hot and dry too.”

All in all, Andrew believes things have gone as well as they can in a season where lots of factors are uncontrollable. “Nutrient uptake has been lacking because of the dry weather, particularly in spring crops. Fungicide timings have been good, with no extended spray intervals so this harvest isn’t going to be a disaster because there’s a good margin there at current prices, even if the dry weather hits yields.”

As far as septoria is concerned it’s a case of so far so good, with disease confined to the lower leaves in most varieties. Instead it’s yellow rust that’s been causing the most concern.

“KWS Zyatt is the worst variety in my area and I’ve had to apply a T1.5 spray in some places to keep on top of the yellow rust. In general, many crops are the more resistant varieties and even Gleam (rated 5 for yellow rust) seems to be doing okay.”

Even though yellow rust has been reported on the highly rated variety KWS Extase (8), Andrew says he hasn’t found any on the variety in his locality.

Further south in Hampshire, AICC member Nick Wall of Crop Management Partners, describes the spring as ‘rapid’. “It’s been dry but we’ve fared well with rain over the past couple of weeks with approx 38mm (1.5 inches) so far in May. Even though it’s dry, we did have some decent rain in early March which has kept crop going. My colleagues in Kent are much drier,” he says.

In his area, crops had reached leaf three fully emerged (T1 timing) in mid-April, which is about normal, and then growth sped up with ears emerging in all wheat crops during the third week of May, by which time early drilled Extase was just reaching anthesis. “It’s two weeks earlier than usual,” he says.

T2s went on mid-May and were hampered slightly by wind and showers. “On average the gap between T1 and T2 was three weeks and where sprays did go on a little late, it was still within a week of rainfall so I’m confident we will have just enough ‘kick back’ control from the fungicide.”

Nick has chosen to be a little more robust with his fungicide approach, with memories of last year still fresh in his mind when late rainfall caused a septoria resurgence that took a toll on some crops.

He notes leaves four and five as being quite dirty in some varieties, especially in early drilled wheat. “The impact of drilling date on disease is particularly visible this season. I have some KWS Firefly in the ground, that was seed carried over from the previous year, but it was late-drilled and it’s still clean.”

Overnight showers and damp mornings are likely to encourage septoria and Nick says that in early drilled crops it’s beginning to move up the canopy.

Yellow rust is very evident in his area, particularly in Zyatt and Gleam, but also SY Insitor, but it’s manageable, he says. “My colleagues in Kent have been chasing yellow rust all season and, on some varieties, they’re having to protect each leaf as it emerges. Yellow rust has even been seen in spring barley.”

Zyatt has been particularly badly affected and Nick says that yellow rust is making quality wheat production increasingly risky for growers. “Quality wheats are in demand but the resistance ratings for yellow rust in Group 1 varieties – Zyatt (4) and Skyfall (3) – is so poor that it’s such a big risk now.”

Nick has used a lot of Univoq (fenpicoxamid+ prothioconazole) at T2, which he says seems to have kept yellow rust in check.

Unfortunately Univoq is likely to be remembered this season for some of the problems experienced in spray lines. Andrew says he dodged the Univoq ‘bullet’ this spring more by circumstance than by design due to supply chain issues. “I’ve used a lot of Revystar (fluxaproxad+ mefentrifluconazole) at T2, so it’ll be a good test of how good it is on yellow rust.”

Fellow AICC member Tod Hunnisett has also gone mostly down the Revystar route at T2 because Univoq wasn’t guaranteed to be available. “I don’t like asking growers to buy up front because it compromises the agronomy if I have to recommend what’s already in the spray shed,” he says.

Where Univoq was applied, it wasn’t all without problem. “One grower has a 36m sprayer and had to replace all the nylon pistons and ‘O’ rings at £35 a pop. Every single one,” he grimaces.

Tod’s patch extends across the south coast, from Broadstairs in Kent to Shaftesbury in Dorset, and extending north as far as Newbury in Berkshire. He also looks after crops on the Isle of Wight for good measure.

As in other parts of the country, he reports crops as being two weeks ahead of themselves and says most of his winter wheat is having a T2 spray as ears are emerging due to the rapid pace they’re going through the later growth stages.

Again it’s Zyatt that has the accolade as being the variety with the biggest issue this spring – yellow rust. “Interestingly, I’m seeing more disease where there are sprayer overlaps than misses which makes me think that the yellow rust has taken advantage of a stressed crop. The first fungicide went on with a PGR in horrible conditions earlier this spring so that may have been enough to let disease in,” he believes.

Zyatt is a variety which reminds Tod of the variety Rialto, which he says always used to look terrible once the flag leaf was out. In Rialto’s case it was due to pollen scorch but in Zyatt it’s abiotic spotting that Tod is picking up on flag leaves.

With T2s done and dusted and some crops rapidly heading towards flowering, all three agronomists are turning their thoughts to a T3. Tod says he tends to go heavy early and then pull back on fungicide later if he can. His most likely tank mix will be Oraso Pro (prothioconazole+ tebuconazole) plus Comet (pyraclostrobin).

Nick has room for another SDHI in many programmes so he’s considering whether to use Aviator XPro (bixafen+ prothioconazole) to extend septoria protection. That’s something to weigh up with the mid-anthesis timing for fusarium/microdochium control, particularly as T2s haven’t been on long, he says.

Both Nick and Andrew also look after farms with a regenerative approach and here both report crops as looking very clean.

“In a regen system we’re very considered about variety choice and drilling date to reduce the risk from disease. I’ve picked up fungicide doses to be more in line with conventional farms at T2 this year. Last year the late disease pressure was too much,” says Nick.

Andrew has a farm where silicon is being applied to boost the plants own disease protection mechanisms and he reports that at the moment it looks ‘pretty okay’. “There’s septoria in the bottom of crops and, at the moment, we’re on top of yellow rust. But without fungicides, it’s a bit like walking a tightrope with no bar and no safety net – it certainly makes you think differently,” he says.