This section has Psa-V information and orchard-management guidance for growers. To access this information use the topic buttons listed on the left of this page. To help find specific information on this website, use the search function beneath the KVH logo.

Orchard diary—Autumn notes

Autumn is a higher risk period for Psa-V infection/expression

  • Psa-V survives better and multiplies faster in cooler, wetter weather.
  • Harvest fruit scars and leaf scars provide multiple entry points for Psa-V.
  • Internal changes in the vine may make it more vulnerable to infection.

Spray coverage

  • Maintain ongoing cover—leaf protectants/elicitors/biologicals/wound protectants.
  • Avoid over-dosing leaves with copper. Excessive use may also cause fruit staining. Use lowest product rates. Application volumes must match canopy thickness—check this with water-sensitive paper. Reset nozzles as required.
  • Consider helicopter applications to reach fresh growth on strung or thick-growing canopies.
  • Protect fruit-stalk scars immediately after harvest—copper at low rates/application volumes, eg 1000l/Ha.

Spray protectants—refer to udpated Seasonal Management Guide V7 (11.04.12)

  • Use only proven products. Absolutely no antibiotic use.
  • Observe product Pre-harvest interval (PHI). Actigard™ use postharvest is allowed.

NB: product information in the table below has been updated Monday 26 March 2012.

Product

Use period

 

Suggested use

Coppers  (use low rates)

7 days PHI

Protectant

Maintain ongoing cover.

Serenade Max™

1 day PHI

Biological

Best suited for low risk situation. Not proven on Hayward.

BioAlexin

1 day PHI

Elicitor

Has 2–3 week activity.

Actigard™

70 days PHI

Elicitor

Allowed post-harvest. Use only when leaves are still healthy. 

Spotless® Ends at fruitset Bactericide Allowed post-harvest. Use only when leaves are still healthy.

 


 Hygiene

  • Continually monitor, targeting high-risk areas—remove and dispose of infected material (secondary symptoms).
  • Clean and sanitise tools between orchards/blocks/vines according to orchard risk.

Harvestbiosecurity risk is high

  • Maintain vehicle/personal hygiene, ie washdown and use of sanitisers.
  • Stop organic material (leaves, mud etc) entering and leaving the orchard.

Vine management

  • Complete male trimming/canopy management/thinning in dry weather.
  • Secure stump suckers and new grafts to avoid chafing and blow-outs. Maintain adequate water, weed-control, shelter nutrition and spray protectants.