Scala 400 SC Fungicide is a product registered by AgrEvo Pty Ltd for the control of bunch rot (grey mould) in grapevines. Bunch rot is caused by the fungus Botrytis cinerea . The active constituent in Scala is pyrimethanil which is a Group I fungicide.
This fact sheet addresses the use of Scala after 80% capfall.
Q. Why does The Australian Wine Research Institute currently recommend that applications of Scala be restricted to before 80% capfall?
A. The recommendations have been developed to satisfy the lowest maximum residue limit (MRL) for any of Australia’s major wine markets after considering available data on the persistence of pyrimethanil, both on grapes and through winemaking.
It is known that if Scala is sprayed onto grapes late in the season (after 80% capfall), residues of pyrimethanil may be detectable in the resultant wine (Cabras et al., 1997).
Some of the markets to which Australia exports wine have a very low MRL for pyrimethanil, or alternatively, have not announced their position on the course of action they would take if pyrimethanil was detected in wine.
To ensure that Australian wine meets MRLs set by all of these markets, the 80% capfall restriction was recommended to grapegrowers.
Q. Can Scala be used after 80% capfall?
A. Scala can be used after 80% capfall if the wine made from the grapes will only be sold in Australia, or to an export market that has an MRL greater than 0.1 mg/kg or otherwise permits residues of pyrimethanil. You can check the MRLs for various markets by clicking here.
Some grapegrowers may be forced to use Scala late in the season due to a lack of effective alternative fungicides, even though the wine is destined for markets with MRLs less than 0.1 mg/kg. In such cases, the winery should have the wine analysed for residues of pyrimethanil prior to bottling, to determine if a potential problem exists.
Cabras, P.; Angioni, A.; Garau, V.L.; Melis, M.; Pirisi, F.M.; Minelli, E.V.; Cabitza, F.; Cubeddu, M. 1997. Fate of some new fungicides (cyprodonil, fludioxonil, pyrimethanil, and tebuconazole) from vine to wine. J Agric. Food Chem.; 45:2708-2710.
This information is provided to inform the wine industry of agrochemical product information, and should not be interpreted as an endorsement.