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FORMULATION & ACTIVE INGREDIENT: REVUS is a suspension concentrate containing 250 g/l (23.4% w/w) mandipropamid.

For the control of Foliar Blight (Phytophthora infestans) and protection against Tuber Blight in potatoes.

RAINFASTNESS: 15 minutes.

PROPERTIES OF REVUS
REVUS is a foliar fungicide for the preventative control of Late Blight (Phythophthora infestans) in potatoes and Downy Mildew in lettuce, and is highly active against spore germination. Uptake into the leaf tissue assures good translaminar activity and inhibits mycelial growth during the incubation period.

DISEASES CONTROLLED
Control of Foliar Blight (Phytophthora infestans) and protection against Tuber Blight in potatoes.

BACKGROUND TO POTATO BLIGHT CONTROL
Late Blight (Phytophthora infestans) is potentially a devastating disease of potatoes. In commercial production, a season-long disease prevention policy is essential. First of all ensure that other control methods are being satisfactorily applied:
1. Prevent re-growth on potato dumps.
2. Destroy all groundkeepers.
3. Plant disease-free seed.
4. Use generous soil ridges to protect tubers.
Integrate this approach with a fungicide programme:
Early Crops
In first and second early potato crops, particularly those grown in the same locality as main crop potatoes, an adequate and full blight protection programme should be applied right up to harvesting or haulm desiccation. This will protect the early crop while helping to reduce disease risk to later crops.
Main Crops
Disease prevention programmes require regular and season-long fungicide use to limit foliar blight development. However, as an effective fungicide programme will preserve leaf area there may be more risk of infecting tubers at harvest, particularly during “heavy” blight years. Completion of the control programme should therefore include a complete haulm desiccant. Lifting of the crop should not take place for at least 10 days after COMPLETE KILL of the haulm. Crops intended for storage should not be lifted while there is any green tissue AT ALL on the leaves or stem bases.
Blight Risk Assessment
The risk of disease is affected by weather conditions (during the crop life) and crop location.
Weather Conditions – Spread of disease occurs under warm, humid conditions. Preferably use a reliable decision support system to determine what frequency of fungicide treatment is appropriate and fungicide type required.

Note: Blight forecasting has often been based on the occurrence of “Smith Periods”.
A “Smith Period” is a 48 hour period in which the minimum temperature is 10°C or more and the relative humidity exceeds 90% for at least 11 hours during the first 24 hours and for at least 11 hours again during the final 24 hours. However, any period of warm, humid weather increases blight risk.
Crop Location – Locations with the highest probability of blight problems are:
1. Areas of the country where extensive main crop or early production takes place.
2. Areas where climatic conditions that encourage disease development occur on a frequent basis.

TIMING
REVUS is a protectant fungicide and therefore the spray programme must start BEFORE blight enters the crop. Commence spraying at the first blight warning or when local weather conditions are favourable for the disease.
Intervals between applications of REVUS should be reduced as blight risk increases, so that protection of the crop can be maintained.
Applications of REVUS should be made at 7–10 day intervals depending on disease pressure.
As disease pressure and the risk of late blight infection increase, the interval should be shortened.
Rates of Use
Apply REVUS at 0.6 litres product per hectare. Up to 4 applications may be made per crop.
Applications of REVUS can be made up to 3 days before harvest.

MIXING AND SPRAYING
Spray Volume
Apply REVUS in at least 200 litres of water per hectare.
Spray Nozzles
A medium quality spray is preferred for application of REVUS. A spray pressure of 2–3 bar is recommended.
Mixing
Make sure the sprayer is clean and set to give an even application at the correct volume.
Fill the spray tank with half the required volume of clean water and start agitation. Add the required amount of REVUS and continue agitation whilst adding the rest of the water.
Agitate the mixture thoroughly before use and continue agitation during spraying and any stoppages.
Thoroughly wash all spray equipment with water immediately after use.
Do not leave the spray liquid in the sprayer for long periods (such as during meal breaks or overnight).