Biology, species and genetic diversity of macadamia lace bugs (MC13008)

What was it all about?

Macadamia lace bug has a significant impact on the macadamia industry, but the taxonomy, genetics and ecology of the pest is poorly understood. This study, which ran from 2014 to 2019, investigated key aspects of the bug including lifespan, food sources, where they lay their eggs, and how far individual insects can disperse.

Researchers collected specimens from seven different growing areas and used both close examination and DNA profiling to precisely identify the problematic species.  They found that several species of lace bugs in the genus Ulonemia, which are native to Australia, have become significant agricultural pests and are responsible for major economic losses within the macadamia industry. They feed on and damage macadamia flowers, and their populations can build up rapidly if left unchecked. The major findings were made available in this fact sheet for macadamia growers.

Results from the testing showed that variation between different infestations is low, which indicates that the bug can be spread across long distances, perhaps by wind or with movement of plant material, people, vehicles and equipment. This means that there is the potential for lace bugs to reinfest managed orchards from unmanaged source populations anywhere within the growing region.

While insecticides are effective at controlling the pest in orchards, optimal management of the species will require area-wide management.

Grower recommendations

• Don’t only rely on pesticides, since this can drive genetic selection towards resistance
• Increase orchard hygiene to control the spread of lace bugs by hitchhiking individuals
• Coordinate pest management over a wide geographic area.

ACT NOW

• Download the fact sheet on macadamia lace bug which includes an identification guide for growers.