Timing of elicitors and CPPU
While copper forms the base of the Psa-V spray programme through spring, products such as Actigard™ and Ambitious should also be included to provide additional protection against leaf spot and flower bud infection.
Trials have shown these products are most effective when applied before leafspot symptoms appear and most growing regions will be at, or fast approaching, a canopy stage suitable to application (pictured).
The best timing for Ambitious is mid-way between bud-break and flowering; or if two applications are planned, apply three weeks post bud-break, with the second two weeks later. As a guide, shoots should be around 100mm long. Use of this product on Gold varieties is not recommended.
Foliar Actigard™ may be applied as soon as the canopy is sufficiently developed for absorption. If vines are under stress from factors such as wind, frost and drought it may be prudent to delay applications until the canopy is more established. A second application of Actigard™ immediately pre-flowering will assist with Psa-V protection during flowering.
Coppers need to be reapplied to match rate of shoot extension, with all sprays applied at label rates. Maintain comprehensive spray programmes throughout spring, irrespective of weather patterns as risk events can arise quickly. The removal of infected material from canopies is equally important in reducing risk of infection spread.