Brazilian Wilt - are we ready?

24 August 2017

There’s been some good media coverage recently on a plant disease of real biosecurity and conservation concern. Radio NZ initially covered the topic explaining how the disease called ‘Rapid ohi’a death’ is wiping out native trees in Hawaii and could spread throughout the Pacific.

The fungus behind the plant disease is Ceratocystis fimbriata - or Brazilian Wilt as its more commonly known - one of Kiwifruit's Most Unwanted and a soil-borne fungus causing significant damage to kiwifruit orchards in Brazil, and has been a major focus of our biosecurity readiness activities.

Infected orchards in Brazil have suffered up to 50% vine loss over the last five years and there is no known treatment available. If the disease was to arrive in New Zealand it could establish and result in 10-30% vine loss per year on infected orchards. We know that vine death can occur very rapidly following infection with Hayward or Bruno rootstock appearing to be the most affected.

KVH has made significant progress in the last 12 months towards ensuring we are prepared to manage this major threat, including the completion of a Brazilian Wilt Readiness Plan in May.

Readiness plans are developed under GIA, in partnership with the Ministry for Primary Industries (MPI) and outline exactly how we would respond should particular organisms be detected in New Zealand. The Brazilian Wilt plan also details current knowledge gaps and research needs that will be funded and addressed by KVH and Zespri.

When it comes to reducing the risk, there is a very real chance of eradication should the pathogen be discovered early enough in a confined area, and able to be contained. As we don’t know how long it takes for symptoms to develop from the time of infection (months or years), containment of a pathogen that we cannot see is only feasible if the industry follows biosecurity best practice at all times – source clean plant material, check and clean everything that enters your orchard and report anything unusual.

There’s more information about Brazilian Wilt, including a fact sheet and detail about research programmes underway, on the KVH website. You can also read an article about how KVH is preparing for this threat in the new KVH Annual Report 2016-17.