While Psa-V progression has slowed during the 2014-15 growing season in most regions, its important growers don’t become complacent with their Psa-V management, particularly as we head into winter.

A better understanding of managing the disease, combined with a fairly warm, dry growing season has resulted in a significant drop in Psa-V levels on most orchards.

However some orchards, particularly those in challenged locations, still have significant Psa-V pressure impacting on yields and orchard profitability. The photo above shows cane dieback and fruit shrivel on a Gold3 orchard in a challenged Waihi site.

This is a reminder that disease levels could quickly increase in any orchard as the weather becomes cooler and wetter, and if Psa-V is not proactively managed.

Immediately after harvest apply copper to protect fruit stalks. Using summer rates of copper will minimise leaf damage and is recommended if copper is being combined with Actigard™ as leaves need to be actively photosynthesising for Actigard™ to be properly absorbed. Where maintenance of leaf condition is less critical apply copper at winter rates. Do not apply Actigard™ to stressed vines.

All growers should be maintaining protective spray programmes in the lead up to winter and ensuring best-practice hygiene is carried out through the remainder of harvest and pruning. This will provide the best possible start for orchards next spring.

Peter Mourits, KVH Operations