AGRICULTURE Victoria research scientists have identified a bug and a mite in America that could help tackle one of Australia’s worst agricultural weeds – silverleaf nightshade.
This research builds on Agriculture Victoria’s previous biological control successes for pasture weeds, the most notable being the introduction of insects to control Paterson’s curse, which has saved millions of dollars for Australia’s livestock industry.
Silverleaf nightshade is a ‘Weed of National Significance’ and is a major problem for the red meat and grain industries in Southern Australia as it competes with other crops, depletes soil nutrients and is toxic to livestock.
The lace bug is native to Texas and the mite is native to Argentina where they have both caused damage to silverleaf nightshade without affecting other plants.
Agriculture Victoria research scientist Dr Raelene Kwong said the two species offered a promising natural solution to control the invasive pasture weed.
“Invasive species are the largest bioeconomic threat to Australian agriculture, with weeds alone estimated to cost nearly $5 million per year in control costs and production losses,” Dr Kwong said.
“The introduction of the lace bug and mite to Australia could save the red meat and grains industries millions of dollars through improved animal health, increased productivity, and reduced control costs.
“Biocontrol such as this provides an environmentally-friendly and self-sustaining approach that can reduce the need for costly herbicides, which can damage other crops, lose their effectiveness, and are associated with health concerns.”
Agriculture Victoria research scientists have undertaken pre-screening trials of the mite in Argentina and field trials of the lace bug are expected to take place in Texas in December.
If they are suitable, they will be imported to the advanced quarantine facilities at the AgriBio Centre for AgriBioscience in Victoria – Australia’s premier state-of-the-art agribioscience facility.
There, they will undergo rigorous screening against closely-related native, ornamental and crop species, after which, the results will be submitted to the Australian Government for a detailed import risk analysis.
Agriculture Victoria is also leading the Australian component of a new international biocontrol initiative to combat two other major agricultural weeds: serrated tussock and Chilean needle grass.
This research is part of the Commonwealth Government’s Rural Research and Development for Profit program, conducted in collaboration with AgriFutures Australia, Meat and Livestock Australia, the Grains Research and Development Corporation and Primary Industries and Regions South Australia.