NZ: Asian wasp introduced to control apple pest

New Zealand orchardists are going to be getting a little help from Kazakhstan in the fight against a fruit pest - scientists from the New Zealand Government's Plant and Food Research Institute are introducing the central Asian Mastrus waspin a bid to wipe out the codling moth.

About 1,000 Mastrus wasps were released in the eastern North Island Hawke’s Bay region this Thursday in the first field appraisal of the parasitoid wasp as a “biological control agent” in the local pipfruit orchards, said a statement from Plant & Food Research.

Control of the codling moth cost the New Zealand pipfruit industry between 8 million and 12 million NZ dollars (6.57 million and 9.86 million U.S. dollars) each year, according to Pipfruit New Zealand, the industry representative group.

“Whilst the presence of a single moth in a shipment can impact on market access for all New Zealand apple exports to codling moth sensitive markets, the industry is also focused on reducing the use of chemical pesticides,” Pipfruit New Zealand technical manager Mike Butcher said in the statement.

“The introduction of the Mastrus wasp as a biological control agent is an important new component to our system that currently includes mating disruption, a codling moth specific virus and selective chemistry. This release is an important step in meeting quarantine requirements for our premium markets.”

The female Mastrus wasp lays its eggs on the moth larvae, and when the wasp larvae hatch, they feed on, and eventually kill, the codling moth larva. They then emerge as adult wasps, which seek new codling moth larvae on which to lay their eggs.

“Biological control agents, such as parasitoid wasps, play an increasingly important role in controlling pests as chemical interventions are reduced,” Plant & Food Research scientist John Charles said in the statement.

“This species, which originated in Kazakhstan, has been established in other countries, particularly in the U.S.A., for control of codling moth, and these initial releases in New Zealand will help us to determine how well they survive in our environment and control the pest.”

Source: nzweek.com

Publication date: Thu 1 Nov 2012