Wagga researchers look at benefits of ladybeetles for crop pest control

Dr Joanna Holloway of the Department of Primary Industries, with some of the research project's aphids and ladybeetles. Picture: Kieren L. Tilly
Dr Joanna Holloway of the Department of Primary Industries, with some of the research project's aphids and ladybeetles. Picture: Kieren L. Tilly

Ladybug? Ladybeetle? Ladybird? 

It’s ladybeetle, according to Department of Primary Industries entomologist Joanna Holloway, who is involved in a research project test the ability of these “beneficial bugs” to manage insect pests in crops.

Dr Holloway said pests such as aphids not only damage crops, but also spread viruses.

Dr Holloway and technical officer Rachel Wood are raising colonies of four ladybeetle varieties, with the hope of helping growers reduce the use of sprays and consider the use of beneficial insects.

“What we are looking at is how well they control aphids, so we are looking at field experiments where we set up cages and innoculate them with a number of aphids and a number of ladybeetles,” Dr Holloway said.

 Rachel Wood, a technical officer with the Department of Primary Industries. Picture: Kieren L. Tilly

Rachel Wood, a technical officer with the Department of Primary Industries. Picture: Kieren L. Tilly

“We are also doing lab experiments to look at how many aphids are eaten by a ladybeetle at one time.

“This is eventually going to come out with an economic threshold where a grower will look around his crop and go ‘yes I’ve got this many aphids, but I’ve got this many ladybeetles, so I don’t need to spray’ or ‘I don’t have enough beneficials, maybe I do need to spray’.”

Ladybeetle pupae. Picture: Jody Lindbeck

Ladybeetle pupae. Picture: Jody Lindbeck