Pesty threat targets growing mung bean industry
A HIGH crop value paired with good rain has attracted the largest number of mung bean growers the South Burnett and wider Queensland region has seen in years.
But with the rapid increase, the industry said it was more important now than ever to understand and target its threats.
Senior Pulse Entomologist Hugh Brier said mung beans were at the mercy of the very damaging mirid bug, but this was not always so well known.
"It was only in the 1990s they became an issue, and were recognised as a pest," Mr Brier said.
"And people didn't know what damage they caused."
For years agronomists and growers asked whether green mirid bugs did much damage in summer pulses like the mung bean, and the short answer was they simply didn't know.
Following a Department of Agriculture and Fisheries Entomology trial, the results were in that, yes, they did cause damage and did pose a real threat to the crops.
Mr Brier said it was important to "know the enemy" and to make people aware of when the risk periods were and how to best approach it.
He said he worked to quantify the damage mirid bugs did to mung beans and worked to establish what level of crop damage was unacceptable.
He said mirid feeding caused spotting on the seed and this hugely impacted the quality of the bean.
"It might mean a grower throws away $100 to $200 from each tonne, $400 per hectare," he said.
And for a mung bean crop, he said quality was everything.
"It's very critical because it's exported into Asia," he said.
Fellow entomologist Melina Miles said "it's all about the appearance of the seed" in mung beans, as it was in faba beans.
"If it's discoloured it's unacceptable," she said.
"Mung beans, similar to faba beans, are sold on quality."
When a recent entomology trial determined mirids caused dark spotting on the seed coat, Ms Miles said the next job was to target the threat and control the bugs.
She said it was important to work out what level of spotting caused too much damage to the crops.
"Sometimes it costs more to control them than the amount you would hope to benefit from your yield," she said.
"It's an economic no brainer, and we have to find out where that tipping point is."
Ms Miles said this was a leading focus for her team.
And now with a growing number of mung bean crops sprouting up, there was more demand now than ever before, to understand the pest.