Send comments and bug observations to:
Richard Llewellyn
richard@bioresources.com.au

Top left: “Large” Anastatus parasitising “very small” GVB eggs

Above, Mackays papaya showing adjacent rainforest.

Previous BLOG

August Update../../2015/1/14_JANUARY_UPDATE_2015.html../../2015/1/14_JANUARY_UPDATE_2015.htmlshapeimage_2_link_0

More feedback from Mackays.
40 ha Papaya, Tully Nth Qld

Bugs numbers are now extremely low. No spraying in the main crop for 2 years. A little in patches on young crop. This is a huge change from a few years back where bugs were a constant issue requiring spraying and this then led to problems with mites which then had to be sprayed and so on...

Back in 2013 I visited a large pawpaw farm near Tully (see link to previous story) where we had started Anastatus releases. It looked like a good set up for Anastatus releases with bush next to the crop.

Big increase in other predators in the crop - assassin bugs and spiders most obviously. Both feed of bugs. So now after 3 years these predatorys are likely to be adding to the success of control and cleaning up the bugs that get past the Anastatus.

A problem has arisen with this increase in spiders. Some fruit bunches are covered in spider webs. These have to be removed by this pickers. mackays are currently figuring out how to cope with this issue - pickers wear cotton gloves and carry a small brush on their belt...?

No insecticide sprays has resulted in increased spider numbers

Anastatus also parasitises Green Vegetable Bug eggs

We have been establishing a GVB culture with the view of producing GVB parasitoids - Trichopoda and Trissolcus. GVB is a major pest is macadamias, soybeans, corn and tomatoes.

Along the way we discovered by accident that Anastatus will parasitise GVB eggs - they managed to get into our GVB culture.

Anastatus females out of silkworm eggs are a lot bigger that Anastatus out of the smaller FSB eggs. Anastatus out of silkworm eggs will parasitise the even smaller GVB eggs. And out of these small GVB eggs comes a very small Anastatus. If this wasps parasitises another large silkworm egg then a large wasp emerges!!

We have also had word from a grower in North Qld that started releases of Anastatus in Autumn this year. He reports a dramatic decline in GVB in his passionfruit this season and hasn't had to do the typical sprays for them. He still has FSB at this stage.

Trissolcus wasps now available for GVB

GVB parasitoids have been release by government departments over the last 50 years. They can make a major contribution to control of this important pest under the right conditions. They are typically in low numbers coming out of winter and spraying in crops slows their build up further each season.

We believe releases of these parasitoids early in the season will speed up the natural increase and releases again in Autumn will reduce the numbers of overwintering GVB.

Last year we worked on a system for rearing GVB so that we could mass rear its parasitoids. A few months ago, we collected Trissolcus wasps, the major egg parasitoid of GVB, from a vegetable crop at Bundaberg.

So, we are now rearing Trissolcus. We have a long way to go in refining the mass rearing system but are starting to have wasps available for release.

We think these wasps can make a very useful contribution to GVB control in large orchards where GVB is an issue and in low chemical vegetable production and organic farming. Local area releases will enhance their effectiveness.

So, if you are interested, contact us to discuss the suitability of Trissolcus releases to your farm situation.

GVB eggs parasitised by Trissolcus wasps