Grains Research and Development

Date: 01.11.2001

Bugging the aphid problem

THE Queensland and northern NSW grains industry is rolling out the red carpet for a couple of pest-hungry bugs - one best described as 'the illegal immigrant' and the other as 'the one that got away'.

The 'illegal immigrant' is the spotted amber ladybird, Hippodamia variegata. Originating from Europe, Russia and China, this ladybird was imported to the United States in the late 1980s because of its reputation for devouring crop pest aphids.

Queensland Department of Primary Industries principal entomologist, Bernie Franzmann, found the ladybird in the Lockyer Valley, west of Brisbane, and later in sorghum crops at Warwick and Dalby on the Darling Downs.

"The spotted amber ladybird will be a useful addition to integrated pest management practices in Australia," said Mr Franzmann. "In just a few years after its accidental arrival in South Africa in 1967, it established itself throughout the country and became the most important predator of the Russian wheat aphid.

"It has been observed eating corn aphids on sorghum in Australia, cotton aphids in China and potato aphids in Poland. It is also found on peanuts, lucerne and beans, and prospects are good that it will benefit any plants affected by aphids."

It was Mr Franzmann who, a couple of years ago, uncovered and identified a minuscule wasp - Lysiphlebus testaceipes - 'missing presumed dead' since shortly after its release in Australia in 1984.

After 15 years in the wilderness, the wasp was found on sorghum crops as widely spread as Tamworth, Dalby and Emerald. Mr Franzmann made the find while surveying sorghum production areas across northern Australia as part of a project supported by growers and the Federal Government through the GRDC.

The good news for growers is that both insects attack crop pests and will otentially play a useful role in the natural integrated pest management systems increasingly being adopted by Australian farmers.

Program 2.3.1 Contact: Mr Bernie Franzmann 07 4688 1313

Region National, North, South, West