Weighty claims made as strob gains approval
Weighty claims made as strob gains approval
By Charles Abel
DESPITE a last-minute delay receiving approval from the Pesticides Safety Directorate, Syngenta has launched its new broad-spectrum cereal fungicide Acanto, targeting the barley market and T1 wheat sprays.
"Disease pressure is significantly ahead of last year, so it is a timely launch for UK cereals growers, offering them the chance to get crops off to a clean start and preserve the good yield potential that is already there," says Acanto brand manager Erwan Strullu.
Syngentas claim for T1 supremacy in this years wheat crop strob wars is based on picoxystrobins good curative and broad-spectrum activity and best of the strobs mobility to protect new growth.
Curative activity on yellow rust beats all strobs, including pyraclostrobin, says Syngenta senior pathologist Jeremy Godwin. It is comparable with BASFs strob against septoria.
That curative kick-back activity is important at T1 when disease may not be fully evident, allows more flexibility when choosing a triazole partner and makes application timing less critical, he says.
Mobility within the plant is also important at T1 to protect new growth, unlike at T2 when a fungicides main job is to coat and protect emerged leaves, says Dr Godwin. Unlike any other strobilurin fungicides, picoxystrobin is absorbed rapidly and moves up the leaf and through the air to spread its effects to new growth.
"It is very forgiving in terms of spray quality, because it redistributes so well." Improved sprayer output from reduced water volumes are expected.
Acanto will plug the T1 wheat weakness in the companys existing strob Amistar, which is most widely used at T3. With T1 sprays accounting for 60% of the strob market it is a gap Syngenta is keen to fill.
Yield results
In trials, Acanto at T1 has given best yield results when followed by an Amistar (azoxystrobin) plus triazole mix at flag leaf. "This out-yielded programmes where the same strobilurin was used at T1 and T2, irrespective of whether that was Acanto, Amistar, kresoxim-methyl or trifloxystrobin," says technical manager Beth Hall.
In barley Acantos curative activity against net blotch even outstrips triazoles, and rhynchosporium control beats all strobs, claims Dr Godwin.
In trials during last years low disease conditions Acanto-based programmes outyielded other strobilurins more than 80% of the time, giving an average 0.3t/ha yield advantage over Landmark (kresoxim-methyl + epoxiconazole), for example.
"Including Acanto in barley fungicide programmes has given better green leaf retention than other strobilurins, better control of rhynchosporium, net blotch and ramularia, and better yields," says Mrs Hall.
Acanto was approved in Eire and Germany last year, but too late for significant farm use. No LERAP-type buffer restrictions are expected, but a small price premium over Amistar is likely, says Mr Strullu. *
• ADASs view of the role for the new strob fungicides, page 54.