Last week many regions across south-eastern Australia experienced heavy rains. These conditions have increased the risk of berry split and fungal disease development.
In the lead up to harvest, the aim is to protect clean fruit and prevent the spread of new and existing fungal infections. A number of agrochemical options are still available; however an effective management strategy should consider the following:
- Ongoing monitoring
- Spray coverage
- Resistance management
- Time to harvest
Below is an excerpt from the 13/14 ‘Dog Book’ to guide the management of key diseases in the approach to harvest. This is not intended to be an exhaustive list, rather it is based on enquiries received relating to existing outbreaks.
It’s also important to note that single site products in the following list should not be used curatively against existing infections.
| Active constituents | Notes | Restriction on use | |
| Powdery mildew | Potassium bicarbonate (Ecocarb) | Eradicant properties, no protective activity | Use no later than 7 days before harvest |
| Hydrogen Peroxide+peroxy acetic acid | Suppression only | Use no later than 7 days before harvest | |
| Sulfur | Protectant | Use no later than 30 days before harvest | |
| Botrytis | Potassium salts of fatty acids(Ecoprotector) | Protectant with eradicant properties | Use no later than 14 days before harvest |
| Hydrogen Peroxide+peroxy acetic acid | Suppression only | Use no later than 7 days before harvest | |
| Iprodione | Protectant | Use no later than 7 days before harvest. Consult your purchaser before spraying within 30 days of harvest |
For more details please consult the 13/14 Dog Book and your winery.
The Dog book is also available as an app that can be downloaded for free from iTunes or Google Play.
Further assistance: The AWRI offers a free and confidential help desk service on technical issues, to all Australian grapegrowers and wine producers. Should you require further assistance, please call the AWRI’s help desk on 08 8313 6600 or email: viticulture@awri.com.au.