Following its successful launch and use in wheat, BASF's Xemium-based fungicide, Adexar, has gained approval for use in malting barley in time for the 2014 season. The approval granted by the British Beer and Pubs Association (BBPA), with testing undertaken by Campden BRI, opens the doors to treating spring and winter barley crops destined for both the brewing and the distilling markets.
Already established as a fungicide of choice for growers chasing wheat yield and quality, both agronomists and growers have welcomed this label extension for Adexar according to the BASF's Peter Hughes.
"The market sees the timing of a new, robust alternative to prothioconazole as invaluable for barley growers given the heightened awareness that fungicides with different modes of action need to be used and mixed to prevent the buildup of resistance," he explained at a launch in the Glen Garioch distillery, Aberdeenshire.
Mr Hughes recounted that: "For many years prothioconazole has been the deserved product of choice for barley growers, but, the reliance on it is too heavy." He said that around 85% of all barley crops are sprayed at least once with prothioconazole per season and about half of the winter barley crop receives two sprays of the azole.
"From a balance of chemistry loading, this continued reliance on one active is not a healthy situation for the sector to be in as we strive to protect our active ingredients." Added to this, prothioconazole is also used increasingly widely in oilseed rape, amplifying the reliance of the product across the commonplace cereal and rape-only rotation.
In trials conducted by ADAS, SRUC, Scottish Agronomy and BASF themselves, Adexar has earned itself a position as a fungicide with activity as good across the main barley diseases Rhynchosporium, net blotch and Ramularia, added BASF's UK technical lead, Steve Waterhouse.
"The treatment of disease susceptible varieties like Cassia and Maris Otter with Adexar has given very good control of both Rhyncho and net blotch, even at lower doses than 1.0 l/ha" he said.
Added to this, Mr Waterhouse highlighted the Hyperflow capabilities of Xemium, the SDHI component within Adexar - its inherent ability to "reach parts of the plant other fungicides can't reach" - as hugely beneficial. "Xemium has flourine which together with the unusual ability of the molecule to flex, makes it very systemic, meaning that the molecule can move easily through cell walls and the cells themselves because of its lipophylic (fat-loving) and hydrophilic (water-loving) capabilities."
Adexar's useful properties extend further still he pointed out. "Trials have shown a yield benefit from Adexar due to factors in addition to disease control, which can be explained by its proven ability to enhance the crop's green leaf area (GLA), water use efficiency and improvements to plant nitrogen utilisation."
Dr Fiona Burnett from SRUC has seen similar effects in her own trials; "leaf chorophyll was subtly higher in Adexar treated plots versus straight epoxiconazole. At early ripening (GS82) a 5% uplift in photosynthetic activity may be a small percentage, but it can uplift yield significantly," she said.
The approved dose from the BBPA is62.5g Xemium/crop, so a maximum of 1 litre/ha Adexar at GS45 (just before ear emergence).
BASF recommendations are slightly favoured towards T1 at dose rates of 0.75-1 litres/ha, but also advise that it is a very effective option at T2 at the same dose rates. "We'd also recommend the inclusion of a strobilurin somewhere within the programme such as Comet 200 to support resistance management."