An overview of the Australian fruit fly problem

Transcription

1 An overview of the Australian fruit fly problem A/Prof Tony Clarke Queensland University of Technology Queensland University of Technology

2 from Dominiak & Daniels 2011

3 Fruit fly problem Why are fruit fly a problem? Direct crop damage Impact on market access (domestic and international) Why are they such a problem now?

4 Current fruit fly problem Biological problem is probably much the same as its been for the last 40 years. Issues now are the regulatory changes loss of D&F for in-field and post-harvest control; and potential loss of the area-free zones. Changing rules for market access. These problems are exacerbated by a general decline in government support for., D. & E.

5 Why are fruit fly different from any other pest? In many ways they are not, they can be killed like any other insect, but they do have some have attributes which make them unusual.

6 Lots of them Domestically

7 Lots of them Internationally

8 Implications One size does not fit all controls need to be tailored for different species. Political potential to use flies as technical barriers to trade Threat concentrating on just one or two species is risky because another one can pop its head up.

9 Biology Host range Both Q-fly and Med-fly are extreme polyphags This puts them into a group of well less than 0.1% of all plant feeding insects in the number of different plants they can infest. Breeding Produce lots of off-spring, and multiple generations per year Mobility Free flying adults, with good dispersive capacity

10 Implications Studying the biology of the flies on only one crop (or crop type) will only give part of the total answer to the flies. What happens in your orchard is only part of a much larger story of fruit fly populations in a region. These are cross-commodity pests and should be treated as such.

11 Approaches to management For the last 40 years little thought has had to be given to management. Cover sprays give good in-field control, then post-harvest dips or sprays give market access confidence. Alternatives are available (esp. protein bait spray and MAT in combination), but have not been greatly adopted through lack of need.

12 Approaches to management The loss of D&F forces a greater sophistication into the management of fruit flies. It is clear that governments are forcing fruit fly control back on growers. Initially fruit flies need to start being rolled into on-farm IPM packages Ideally Area-Wide IPM should be applied for fruit fly, but logistically more a challenge.

13 Approaches to management Tools for management Protein bait spray or other female attractants Male annihilation / mass trapping Sterile Insect Technique Barrier treatments (oils, clays, nets) Breeding for resistance Natural enemies (pathogens, parasitoids)

14 Alternative cover sprays MAT; Protein Bait Spray SIT; MAT; Protein bait spray Pathogens; Parasitoids; Soil drenches Mechanical disruption Fruit fly Life-cycle Existing pre- and post-harvest treatments Parasitoids; Host resistance

15 Other farm trees Stone-fruit orchard Citrus orchard egional towns Native vegetation

16 Host use While Queensland fruit fly has a very large host range, not all fruits are equal. Non-host status (e.g. pineapple) or conditional non-host status (e.g. hard green mango) are avenues which need to be explored further either for market access on their own, or for timing of in-field controls. esistance breeding is a whole new field.

17 What now? National Fruit Fly Strategy (big picture, but little or no budget) Plant Biosecurity CC (strategic investment, relatively small budget for size of problem) HAL (fragmented budget, need for crosscommodity investment) Private industry?