Management on commercial orchards
Here are four approaches you can take to protect your produce from Queensland Fruit Fly.
Practice good on-farm hygiene
Collect and destroy any rotting, overripe or unwanted host produce, whether it is on the ground or still on the tree, as this can become a breeding ground for QFF.
Intact fruit may appear unaffected, however it is good practice to routinely check your produce for the presence of QFF larvae by cutting open some fruit, to improve the chance of detecting larvae.
If you have any unwanted or neglected QFF host produce trees, it is best to remove them to reduce the risk of attracting QFF to your orchard.
Adult QFF activity can be monitored in orchards and surrounds by using traps containing synthetic sex pheromone attractants or food lures. The most commonly used sex pheromone attractant (or lure) is Cuelure, which attracts and kills only male QFF. A wide range of food lure traps are also available, which attract both sexes of QFF.
Traps are placed in the shade of the canopy of host trees and the contents checked on a weekly basis during the warmer months and then fortnightly during the winter months.
If enough flies are detected in an area of the Greater Sunraysia Pest Free Area (PFA), an outbreak is declared in a fifteen kilometre radius from the detection epicenter. Once an outbreak is declared, restrictions apply to QFF host produce moving from an outbreak area to other parts of the PFA.
When no fruit flies have been trapped within a PFA outbreak area for a prescribed period, the outbreak is considered to be eradicated and the area can be reinstated as being free of fruit fly. The length of the prescribed period varies according to the time of year when the last fly was caught and how this relates to the speed of the fruit fly's reproductive life cycle (generally referred to as one generation plus 28 days).
Baits can be used to reduce QFF numbers on-farm. They consist of a protein attractant mixed with an insecticide and are usually spot-sprayed onto the trunks or foliage of both host and non-host trees.
Adult flies are attracted to the bait as a food source and are killed by the insecticide.
QFF baits can be purchased from local chemical resellers.
Cover spraying can be used to directly control adult QFF on contact, and some systemic chemicals also destroy eggs and larvae within fruit. A mixture of an early season baiting program followed by cover spray treatments can further help to protect produce from fruit fly infestations.
There are also options for spraying fallen fruit and fruit that will not be harvested to manage QFF infestations late in the season.
All chemical applications must be applied according to the directions on the product label or an Australian Pesticides and Veterinary Medicines Authority Chemical Permit.