Asian Apple Market Access

May 2020

Finding safe and sustainable ways to bring pest-free apples to the Asian market

The New Zealand Apple Industry has a long history of meeting market demands using innovative management techniques to reduce chemical residues and fruit-borne insects. Now there are newly developed safe and sustainable ways of producing residue-free and pest-free apples for our Asian markets, particularly Japan and Taiwan.

The Integrated Fruit Production Programme of the 90s saw the phasing out of organophosphates and other harsh chemicals, setting new industry standards for low residues, but consumers have been demanding ever lower residue limits.  

In 2007 the industry started the Apple Futures Project as the next step towards the production of safe fruit in a sustainable way using largely biological controls.

Current orchard management aims to use “soft” sprays at minimum levels. Growing-degree days are noted and when 80 to 100 are recorded moths will have started laying eggs and so these are targeted with an ovicidal spray.  Pheromone traps are used to monitor codling moths and when numbers start to increase pheromone dispensers are used to confuse male moths and disrupt mating. This has been successful in reducing moth populations in orchards and so reducing the need for sprays.

A recent development is the use of Sterilised Insect Treatment (SIT) – where imported sterile moths are spread throughout an orchard and “mate” with local moths.  The result has been dramatically reduced moth populations in and around the orchard.

Apple washing also reduces residues and insects on the fruit.  For European and many other markets that are residue conscious this satisfies their demands for no detectable residues.

However, Asian markets are more focused on insect pests and some (notably Japan) require fruit to be 100% pest free.  The only currently accepted way of achieving 100% uses fumigation with low levels of methyl bromide gas.  The New Zealand industry wants to move away from methyl bromide, which is an ozone depleting gas, and is developing a systems approach that it hopes will eventually satisfy Japan and retain access to this lucrative market.

The main insect pests of concern in Asia are codling moth and apple leaf curling midge (ALCM).  For codling moth a systems-based approach to risk management is used along the entire pathway.

This involves:

  • Registering production sites
  • Systems of pheromone trap monitoring
  • Treating the crop when a threshold is reached 
  • Independent auditing of crop protection inputs
  • Traceability of the crop and all inputs
  • For Japan, the fruit must be fumigated with methyl bromide.

Plant & Food Research is now working with the industry to find new strategies for producing pest-free fruit (especially codling moth) for Asia, with Japan and alternatives to methyl bromide firmly in mind.

The combined effect of the mating disruption and SIT programmes mean that there is now the potential to develop large areas of low pest prevalence. This has commenced in the Hawkes Bay and the codling moth SIT programme is being expanded. The hope is that results will help convince Japanese officials, allowing New Zealand to negotiate access based on its low risk profile and avoid the requirement to fumigate NZ apples.

A systems approach is also being developed for the ALCM with new components including “lure and kill” techniques and new apple washing technology.

The lure and kill approach to midge control uses sex pheromone and insecticide in a gel that is applied to the base of trees.  Trials have shown that a single application of a 0.4 ml spot of gel can attract and kill male midges for 4-5 months. The result is a dramatic reduction in the midge population and a reduced risk of cocoon presence on fruit at harvest.

Completely new apple washing technology has been developed to remove ALCM cocoons from fruit.  Whereas the old washers could remove only 10-20% of cocoons, the new high-speed washer removes around 90%. It works by spraying individual apples from all sides and thus is much more effective in removing both insect and chemical residues.

At the packhouse, individual fruit inspection is part of quality assurance, as is traceability records of the orchard, its management, and any inputs used.

As a result of this work there seem to be good prospects of retaining the Japanese market without the need to fumigate.

 

Showdown Productions Ltd – Rural Delivery Series 15 2020