The kiwifruit grafting season is about to begin but while it brings the promise of new vines to replace those lost to disease it is not without risk of re-introducing Psa-V.

With plant material posing one of the biggest risks of spreading the vine killing disease, growers are urged to ensure any nurseries supplying stock are registered with Kiwifruit Vine Health as they organisation tests budwood used for grafting new kiwifruit varieties.

Judy Trafford bundles Budwood fresh from orchards. Photo: File.

KVH CEO Barry O'Neil says 85 samples from budwood suppliers have been tested so far, with only one positive result from an asymptomatic budwood (one which shows no symptoms of the disease).

KVH has received testing results from 14 nursery plant samples, of which five have returned a Psa-V positive result.

Barry says as all the samples were collected from asymptomatic vines highlighting the importance of testing budwood and nursery stock prior to distribution to minimise the risk of Psa-V spread.

Budwood is the term used to describe the portion of a stem or branch with a vegetative bud used to graft onto an existing plant to produce new growth. In the case of kiwifruit this season, most of the budwood is of the new gold variety referred to as G3.

Barry says KVH does not support the movement of infected budwood and is beginning a round of audits on budwood and nursery suppliers.

In order to meet the high demand for budwood, especially for the new variety G3, KVH and the Ministry for Primary Industries, has agreed that providing the budwood is non-symptomatic, limited movement may be allowed in selected regions.

The dispensation includes that budwood moved from Psa-V positive orchards is from Hayward, Gold3, M33, M91, G14, Chieftain and Arguta varieties only and can only be taken from vines showing no Psa-V symptoms.

Movement of budwood is permitted between Psa-V positive orchards within the same recovery region only and applies to the following recovery regions: Waihi, Katikati, Tauranga West, Tauranga East, Te Puke, Whakatane and Opotiki. Budwood cannot be moved to an orchard with a ‘not detected' Psa-V status.

All budwood suppliers must have a completed Psa-V Budwood Risk Management Plan as part of the KVH Budwood Movement Protocol which applies for all kiwifruit budwood supply.

Monitoring records completed prior to budwood collection and lab test results also form part of records, as well as any permissions issued by KVH for inter-regional budwood movements.
Growers who propagate plants within their orchards and sell or move these plants off the property, as well as commercial nurseries selling kiwifruit rootstock, plants and seedlings (except those already KVH-accredited) must register with KVH and follow the KVH Movement of Nursery Stock protocol. This includes having a Psa-V Nursery Stock Risk Management Plan in place.