Fruit fly are a severe pest of soft fruits including tomato, capsicum, mandarin, peach, and nectarine. It is not present in all areas but is becoming more common as it spreads into previously fruit-fly-free states including Victoria, South Australia and Tasmania.
There are two main fruit flies in Australia – Queensland fruit fly (a native pest) and Mediterranean fruit fly – which has been introduced into Western Australia. There are also many other types of fruit flies that attack plants in Australia, including the cucumber fruit fly, banana fruit fly and mango fruit fly. The female lays eggs in semi-ripe and ripe fruit, which hatch into maggots (small white larvae), which burrow through fruit causing it to rot and fall from the plant. The maggots pupate in the soil before developing into adult flies that emerge to continue the infection cycle.
The best way to control fruit fly is to keep checking fruiting plants, so you can spot them early. Infected fruit develop soft spots. Remove and destroy this fruit immediately. Use traps to monitor your trees, they are quite small and not easily seen. Traps may also catch other insects so ensure you know what fruit flies looks like.
Fruit fly can be controlled with organic baits and lures. Bagging or using fine exclusion netting can also be effective. Always pick up and dispose of infested fruit to reduce the spread of the pest. A combination of different methods of control maybe needed depending on the infestation. If you need further help, contact your local Department of Primary Industries or your Municipal Council if you are in a fruit fly area.
A healthy garden can also help prevent pest infestation. If your plants are strong and healthy, they may be able to handle and reduce the stress of pests and diseases. Applying Seasol regularly every two weeks during the year can help them to cope with environmental stress. Keeping plants fed with fertilisers such as PowerFeed All Purpose including Natives, better watering and appropriate light exposure can also help build tougher plants.