Seen something unusual? MAKE A REPORT
The recent frost has provided another challenge for many, in what has already been a tough year. With many orchards facing significant frost damage, and the potential for further cold weather, it is important to remain vigilant to the threat of Psa.
Psa protection should take priority especially where there have been gaps in protection ahead of frost events, but also on sites with previous history of Psa impacts.
Late October to early November is typically when symptoms show an upswing and we know Psa infection typically occurs 14 days before symptoms are visible, making these next two weeks important protection periods in our calendar.
Psa protection choice is important. As there is time pressure to get products on effectively, updated information from the Zespri Crop Protection Standard (CPS) on products for frost damage has been distributed and is available on the Zespri Canopy here and is copied below:
Growers have a number of products available – including Aureo Gold, Actigard, Kasumin, Copper, and Botry-Zen, (dependant on vine stress).
If looking to use a bactericide, we would like to encourage Kasumin rather than the alternative Key Strepto. We understand flowering is fast approaching, the Zespri Crop Protection Programme states application of Kasumin should not be within 21 days of flowering. This was to include a buffer for grower mis-step or unexpected timing of flowering.
To support grower response to the recent frosts, Zespri will reduce the 21-day window of Kasumin application to 14 days hopefully giving growers enough time to apply if this is their product of choice. This is still more conservative than the label which states application up to one week prior to flowers opening to allow for any possible residue buffer.
Summer rate copper remains the proven backbone of Psa protectant programmes with applications ahead of wet weather, providing robust ongoing protection to damaged tissue. For copper applications ensure recommended rates are maintained and ensure product is applied in good drying conditions.
KVH has several types of resources available to assist growers with Psa advice, including:
KVH recommends you work with your pack-house to decide strategies to manage Psa-V on your orchard, or contact us directly with any specific questions. Technical support from Farmlands, and PGG Wrightsons - Fruitfed teams can also provide excellent advice on Psa product choice and strategies to rebuild damaged canopies.
NZKGI’s most recent Special Update (from earlier this week) details pastoral care options and we encourage you to take these resources and sources of assistance into consideration if you are facing increased pressure:
KVH investigates reports of unusual symptoms to identify and manage any biosecurity risks.