Fruit Fly
Posted on Thursday 22nd November 2012
Fruit flies are widely recognised as the world's worst economic pest of fruit. Apart from lowering production and making fruit inedible, their presence has severe consequences on trade to sensitive markets, both locally and internationally. Only two species of economically important fruit flies occur in Australia. One is the Mediterranean fruit fly (Ceratitis capitata), which is endemic to parts of Western Australia, and the other is Queensland fruit fly. (DPI,Victoria, 2010)
Life cycle
Fruit fly are most active in the warmer months: October - May. There are four stages to a fruit fly's life cycle: egg, larvae, pupa, fly. Eggs are laid in mature, ripening fruit. When the eggs hatch the larvae begin to eat their way towards the centre of the fruit causing the fruit to decay. Once the larvae have finished growing they will eat their way out of the fruit (which by then has usually fallen) and burrow into the soil. Whilst in the pupa the larva will develop into a fruit fly, upon hatching the fruit fly will seek food and a mate and the life cycle will start again.
Monitoring & Control
Traps: Traps are mainly used to monitor the presence of fruit flies within the area. Most traps that are available on the market are used to lure male fruit flies, with the exception of the 'Cera Trap' which lures both male & female fruit flies.
Sprays: Sprays can be used on their own or in conjunction with a bait suitable for foliar spraying. Recently, Fenthion based products such as Lebaycid have had to remove recommendations for home garden fruit fly control. This leaves only spinosad based products such as Nature's Way Fruit Fly Control. These products have a low toxicity to people and mammals and do not have a withholding period. They attract and kill both the male and female fruit fly. Spinosad based products can be used as a bait in traps, as a foliar spray, or it can be mixed with a bait such as 'Cera Bait' and used as high powered luring spray.
Physical Barriers: Fine mesh bags, fly screen, mosquito netting, shade cloth e.t.c. Physical barriers are used to exclude fruit flies from laying their eggs in mature fruit. Barriers should be tied to the trunk of the tree if fruit fly pupa are suspected in the soil.
