We sent out an email on virus management/ elimination tips a couple of years ago and had very positive feedback, so we thought we would make it an annual reminder.
The New Zealand Winegrowers (Virus Elimination Project), Plant and Food Research and Linnaeus have all done excellent work in this area. To cut a long story short - if you are contemplating removal of virused vines this year, you need to treat with Imidicloprid (Confidor) AS SOON AS FRUIT IS HARVESTED (as Imidicloprid is on not yet registered for application while fruit is on the vines) If you don’t, but still remove the vines - even leaving the land fallow for several years leaves you at high risk of re-infection.
New Zealand Winegrowers has put together some excellent fact sheets which guide you through the whole process (see links below or visit www.nzwine.com).
The key message from us is - you need to treat with systemic insecticide as soon as fruit is harvested, as the chemical needs to be taken up while you still have an active canopy. The vines can be removed 6-8 weeks after treatment- the remaining roots will contain the insecticide for years to come and thus kill any mealy bugs which feed on the remnant roots. Research has shown that even SIX years after removal of a virused vineyard, you can easily find very healthy roots - with mealy bugs happily feeding on those roots then transferring the virus to the roots of re-planted vines. Heartbreaking we know!
We are proud to sponsor New Zealand Winegrowers' Virus Elimination Project, and know this information will be very helpful. If you have any questions or problems with identification of virus, please contact Nick Hoskins on 027 248 7724 or nick@vinemanagers.co.nz
As for us here at Riversun, it has been an outstanding growing season in Gisborne and all our nursery vines are looking amazing (check out the photos on our facebook page). Pre-lift estimates indicate we are well on track for our best ever recoveries and this means we now have some nice surpluses appearing on our stocklist. Given there appears to be little in the way of surplus material available across the wider nursery industry, if you are looking for any vines for planting out this winter/ spring we encourage you to check out our stocklist otherwise just give Amy or Hayley a call on 0800 11 37 47 and they will help you out.
