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Doncaster Ryegrass Innovation Centre - too much ryegrass, not enough crop!

Innovation Centres
15.06.2020

Now that our Syngenta open days will be virtual webinars on topical agronomic issues, here is an update on the season so far at the Doncaster Ryegrass Innovation Centre.

Farmer George Moate gave permission for Syngenta to use one of his heavily infested ryegrass fields for trials to see if we can come up with a solution to his heavy ryegrass infestation. “This particular field has not been in grass for at least 50 years,” commented George, who is extremely frustrated with the triple-R resistance rated ryegrass.

“I have never known a season like this season, it beats the wet one in 2012. Even the drill got stuck in the winter in this field."

George farms 800 hectares near Doncaster, where he mainly grows cereals, oilseed rape and beans, but says he is retiring from farming this year and will most probably rent out some of the land for potatoes and peas.

“I have never known a season like this season, it beats the wet one in 2012. Even the drill got stuck in the winter in this field,” George remarked.

In this particular field, George has drilled winter wheat, but also some spring barley because it was too wet for any more winter wheat to be drilled. “I have not grown spring barley for about 20 years, and I’m not convinced it will yield well, not just because of the lack of rainfall, but also because of the ryegrass pressure,” he said.

Mr Moate grew hybrid barley for the first time last year and that did outcompete the ryegrass, but with the autumn being so wet, he wasn’t able to get the seed in the ground when he would have liked. Even though it was drilled in January, it’s looking surprisingly well.

Controlling the ryegrass on George’s farm has been extremely challenging – one year he went to more desperate measures and bought a weed wiper. The problem with this is that the grass has to be high enough above the crop to work, and because of the varying maturity of the grass, not all the plants are high enough at the same time. This means multiple trips through are needed for successful control.

Focusing on the trials themselves, Andy Cunningham, Syngenta triallist for the ryegrass centre, has been experimenting yet again.

Winter wheat was drilled in October 2019 into extremely wet conditions, demonstrating a non-cropped versus cropped pre-emergence herbicide screen. Andy is looking at the number of pre-emergence actives (9 different actives) that will give the best control of ryegrass in this trial. By far the best control in the non-cropped plots (90% control) was seen from a mix of Defy (5.0 l/ha) + Liberator (0.6 l/ha) followed closely by Avadex Excel (15 kg/ha) + Liberator (0.6 l/ha) + Defy (4.0 l/ha). There was a 7-way tank mix in this trial, and even though control of the grass was above average, there also wasn’t much left of the crop.

The next trial was looking at pre-emergence herbicide timings, with applications from 1 day up to 20 days after drilling (applications made at 1, 5, 8, 11, 16 & 20 days after drilling). The best ryegrass control was seen from the pre-emergence application (Defy 4.0l/ha + Liberator 0.6l/ha) at 11 days after drilling.

Also demonstrated was a post-emergence herbicide timing trial. Pre-em of Liberator + Defy followed by post-em of Crystal at 5, 7, 11, 14, 16, 20, 23, 26, 32, 38 days after the pre-emergence.  Crop effects, in the form of crop thinning, can be seen with post-em applications at 5-16 days after the pre-em, highlighting the importance of getting the sequencing of residual herbicides right.

To replicate the scenario a lot of growers might have found themselves in, Andy then trialled the control of ryegrass as if a pre-emergence application was missed, using both contact and residual herbicides post-em in winter wheat drilled in 1st week January. Although control was not as good as having a pre-em, generally there was still a benefit of the residual chemistry and even better control where Defy was in the mix.

A crop safety trial was also set up where Andy tested different dose rates of Defy to see if there was any crop effect when applied at much higher than label rates. Although it does highlight the importance of mix partners with residual herbicides, even at the higher rates, no crop effect was seen, demonstrating how crop safe Defy is.

An application trial was looking at different water volumes with different nozzle types, speeds and different boom heights. This reinforced Syngenta’s advice that the best option for grass weed control with pre-emergence herbicides is 200l/ha of water, using low-drift nozzles like the Teejet TTI nozzle, with a boom height of 50 cm and travelling at 10 kph.

Other work of note, Axial Pro is showing its benefit against ryegrass and also Defy in spring barley, which we will update at a later date. Given the seasonal conditions that have been thrown at this site, Andy says “It’s great to have achieved the results we have, but hopefully we can all get back to a ‘normal’ year in 2020-21.”

For more information on the Doncaster Ryegrass Innovation centre visit https://www.syngenta.co.uk/innovation-centres/doncaster-ryegrass-innovation-centre