Sunraysia Continues to Battle Fruit Fly Outbreak

Article by: Hari Yellina

Winter has proven to be Sunraysia’s most effective weapon against the region’s extremely high levels of Queensland fruit fly. Narelle Beattie, regional co-ordinator for the Greater Sunraysia Pest Free Area in Mildura, said the cooler weather was already forcing flies into hibernation and laying eggs in fruit across the region. However, she stated that expecting the season to be the saviour come spring would require a concerted effort by growers — not just large-scale commercial producers. Ms. Beattie also stressed the need of home farmers preparing to set traps before late July, particularly around avocado, citrous, and native plants. “The cooler weather we’ve been having has delayed the problem, but the main message now is for everyone to pitch in before spring,” says Ms. Beattie. 

“A harsh winter with frosts will really set the fruit fly back, killing the insects that survive the winter as adult flies – but we’ll need people to bait spray and set traps. “Even a single lemon tree in your backyard or next to the packing shed poses a danger. “The warm, humid autumn created optimal breeding conditions, resulting in a larger problem than we would expect, so population genetics alone warns us about the magnitude of the crisis we could face in a few months if everyone doesn’t do their role.”

Infestations have a direct impact on bottom lines throughout Sunraysia, and the problem is felt right through the production chain to both domestic and international markets. Q-fly is ranked as one of the biggest challenges for Australia’s $13 billion horticulture industry, with infestations having a direct impact on bottom lines throughout Sunraysia and the problem is felt right through the production chain to both domestic and international markets. The Queensland fruit fly has become a well-established pest in Victoria, and growers are learning how to combat it. However, two La Nina climatic episodes in a row have created optimal breeding circumstances for the fly.

During the autumn, a “concerning amount” of flies were identified in wine and table grapes left on the vine after harvest, according to Ms Beattie, and the same was true in the fruit business, with some goods left on trees offering a perfect staging platform for flies. “This year, growers have faced challenges on a number of fronts, including an ongoing and alarming shortage of employees to harvest crops, inaccessible freight markets limited by higher costs or availability – and rising farm input expenses.  Growers haven’t always harvested the entirety of their produce, and some fruit has left on the vines or trees. Q-fly larvae have been found in some of the fruit. “The work we perform now will serve as a springboard for success in the spring and summer, so take advantage of the cooler months to get ahead of the fruit fly.”