The Queensland fruit fly (Q fly) is a pest familiar to most fruit growers in eastern Australia and ranges from the high tropics to the outskirts of Melbourne.
It feeds on citrus, stone fruit, apple and pears, mango, avocado and a host of other fruit.
In China, there is a species of fruit fly with remarkably similar habits. It is the Oriental fruit fly Bactrocera dorsalis (OFF).
Control of Oriental fruit fly (continued from last issue)
In many ways, the methods used to control of OFF are similar to the methods used for Q fly.
Systemic insecticides
Systemic insecticides such as dimethoate are effective but their use is now tightly restricted. That means that the focus must be on adult control using attractants.
Traps
Traps are good monitoring tools for adult fruit flies.
If control with traps is the aim, they must be an extremely efficient design, a brilliant lure and used in very high trap numbers. This is difficult and expensive to achieve.
Bait sprays
Yeast autolysate/insecticide bait sprays are a time honoured method for control of both male and stage-1 female flies but have problems of a short field life, rain wash off and damage to the skin of mangoes.
Attract and kill
Some years ago, United States researchers in Hawaii identified the smells released by bird droppings that are attractive to female fruit flies.
Their focus was on Mediterranean fruit fly. Sinogreen has an attract and kill product using a controlled release system containing these smells within an insecticide treated biodegradable yellow bag.
Like yeast baits, this attracts stage 1 Oriental fruit fly and a range of related fruit flies (including Q fly). It continues working for months, is rain resistant and does not come into contact with fruit.
Male annihilation (cont next issue)
See this article in Tree Fruit April 2018
