Pilot programme to combat codling moth gives spectacular results
Each week thousands of sterile codling moths are being released into Central Hawke’s Bay apple orchards to mate with the local population – the key being no new moth babies are produced from these relationships.
The sterile moths have the same drive to mate, yet no progeny result. By overwhelming the local codling moth population with the sterile moths, imported from a production facility in Canada, the wild moth populations have collapsed.
Of particular importance to the programme is the method for releasing the sterile insects. An unmanned aerial vehicle (UAV), following GPS coordinates, is fitted with special pods that release 20,000 sterile moths over 100 hectares of orchard during a flight of just 10 minutes. These releases mean there may be up to 200 sterile moths for every fertile moth present in the treated orchards.
“We’ve seen dramatic results across the 400 hectares of Central Hawke’s Bay orchards treated with these sterile moths, up to 98% reduction of the wild moth populations,” says Plant & Food Research scientist Dr Jim Walker.
“Within two seasons we expect the codling moth population will be eliminated from these orchards.”
“The codling moth is a major pest for apple growers. This organically accepted technique can help eradicate them, particularly when used in combination with other mating disruption techniques that many growers already use,” says Plant & Food Research Science Group Leader Professor Max Suckling.
“The New Zealand apple and pear industry is always looking for new and innovative ways to control codling moth to reduce our use of insecticides,” says Tim Herman, Technical Manager of New Zealand Apples & Pears.
“We already produce fruit with very low residues, but this research will add to our already sustainable programme of codling moth control and help maintain our ranking as the most competitive apple and pear industry in the world.”
It is believed that the same method could potentially prove effective for eradicating other insect pests, such as Queensland fruit fly, if the species became established in New Zealand.