How to navigate cereal fungicide losses and gains

What the changes to approved cereal fungicides means for farmers

The loss of chlorothalonil after this season – which has a use-up date of 20 May 2020 – will require two important changes to cereal fungicide programmes:

• The first is to consider the alternatives to this important multi-site chemistry for disease control.
• The second is to protect the other active ingredients we do have against resistance.

Timely introduction of Revystar® XE

Just when the industry needed a new, efficacious triazole, the chemistry that has been the long-standing backbone of fungicide programmes, Revystar® XE, from BASF, received authorisation.

Farmers’ trial the new chemistry on their own farms

Based on feedback from farmers – who repeatedly say that they trust the performance of any product more when they trial it on their own farms using their own kit – BASF has launched the Real Results trials network.

50 farmers have taken part and last season they all had access to trial Revystar® XE.

The Agronomics trial management tool explained

Agronomics is a tool for planning and managing field-scale trials. It removes any normal bias from trials, such as variations of soil type and weather, to standardise and statistically verify that any yield difference is statistically significant.

It was developed by ADAS, in partnership with BASF, AgSpace, Trials Equipment Ltd, VSN and the British Geological Survey and funded by Innovate UK and BASF.

What the farm trials assessed

The 50 farmers – from as far north as Aberdeenshire, and as far south as Cornwall – said that they treated their wheat at either T1 or T2 timings, or at both T1 and T2 timings.

The trials were all fully yielded, and diseases on the leaf layers assessed by ADAS. A range of other measurements, such as grain nutrient, harvest index, biomass and specific weight were also made.

What the farmer trials told us

Of the 50 farmers who trialled Revystar® XE 47 complete results were received. On average they saw a yield increase of +0.4 t/ha, with 15 trials showing a statistically significant response over their farm standard programme.

Many noticed a marked difference in how green the Revystar® XE treated crop was versus the standard, with others noticing brighter, thicker straw, resulting from higher biomass, and lower levels of Septoria infection.

What the scientists say

In other Revystar® XE trial work ADAS conducted for BASF, important confidence-boosting discoveries were made.

The first was that, under a range of innoculated Septoria pressures, Revystar® XE controlled all shifted strains of the disease, which means that there is now a triazole that will control the range of pathogens present.

Added to this, Revystar® XE has very good rainfastness which ADAS assessed in irrigated plots to mimic rains showers. There was only a very small reduction in control when the crop was irrigated 15 minutes after applying the product.

ADAS also noted the strong curativity and longevity of control from Revystar® XE against the other azoles on the market.

They made fungicide applications at one, five, 10 and 15-day intervals after inoculation with Septoria tritici.

Revystar® XE gave 30% extra efficacy than the next best azole, prothioconazole; in practical terms giving the same level of control 14 days after infection as you would with a well-timed application of prothioconazole.

The ADAS team noted 80% control of Septoria in a shifted population, even a week after infection, and after 14 days the new active is still giving more than 50% control.

On leaf three, there was also evidence of strong curative activity. Revystar® XE has more than twice the efficacy of the older azoles for all fungicide applications over the 12-day period after leaf two was inoculated.

Come and hear farmers first hand at the Real Results Roadshow

There are a series of BASF Real Results Roadshows running until early March. All are welcome to attend.

Eight Real Results farmers, ADAS scientists and Professor Jenni Dungait, a soil scientist, will be joined by BASF Agronomy Managers to talk about current seasonal challenges and plans for the spring.

The farmers will talk about their Revystar® XE trial results and Professor Dungait will talk about soil remediation options for farmers following the very wet autumn and winter.

*2018 MKDBFB ADAS Rosemaund comparing fluxapyroxad, benzovindiflupyr and bixafen (as Thore).

**BASF trials – Efficacy of various DMI compounds against highly adapted strains of Zymoseptoria tritici in the glasshouse.

Revystar® XE and Revysol® are registered Trade Marks of BASF. Revystar® XE contains Revysol® and Xemium®. Revysol® contains mefentrifluconazole. Xemium® contains fluxapyroxad. Always read the label and product information before use. For further product information including warning phrases and symbols, you can refer to agricentre.basf.co.uk