CHANGE could be afoot in the Northern Territory mango industry if entomologist Austin McLennan gets his way.
At the Katherine Research Station, Dr McLennan and his team are running trials to prove that local mangoes need not be sent to Queensland for expensive post-harvest spraying before export to Asia.
Despite the long-held belief that fruit flies are a significant pest for NT mangoes, Dr McLennan is seeking to demonstrate otherwise.
The reason is a simple one. While fruit fly infestations are abundant in ripe, yellow mangoes, rates of infestation in mature green mangoes are virtually non-existent.
Yet, the current protocols do not reflect this commercial reality.
“We’re trying to show that [fruit flies] won’t develop in the commercial type of mangoes grown in the Northern Territory, provided those mangoes are picked at the correct stage of maturity, which is the green, hard stage,” Dr McLennan said.
“What’s driven a lot of the rules and regulations around fruit fly management, control and the requirements is the knowledge that mangoes can be a host, but most of the data is on them being a host at the soft, yellow, ripe stage, not the hard, green mature stage at which they’re picked.”
Dr McLennan’s trials involve putting a concentrated number of fruit flies in nets surrounding mangoes.
Even in these extreme circumstances, the research shows the flies are still not attracted to the green mangoes and will not lay eggs.
“My work over the last few years has shown that [rates of infestations in] hard, mature fruit is very low and, actually, when you do find it, it’s usually only in fruit that is blemished or damaged in some way, and would otherwise hit the reject bin anyway.”
