And when it comes to preventing damage from citrus mealybug, red scale and other sucking pests, he says taking action early with an insecticide, at 100 per cent petal fall, is ideal.
Rolf is senior horticultural agronomist with Hillston Citrus Operations Pty Ltd, which operates around 1600 ha of citrus crops on properties near Griffith and Hillston in NSW, Mildura on the Victorian border and Emerald in Queensland.
The bulk of the citrus crops comprises navel oranges and mandarins.
With 24 years of experience in export citrus crops in South Africa prior to working in the agribusiness industry locally, Rolf identified a significant opportunity to improve citrus quality for the export market.
He said part of the approach involved seeking an insecticide that would have a perfect fit at 100pc petal fall to control a wide spectrum of pests including citrus mealybug, red scale, soft brown scale, light brown apple moth and citrus leafminer, and that insecticide was Trivor.
“There is nothing better in the market at this stage,” Rolf says.
“ It is an investment, but it is the best value product for that market sector,” he says.
“ We know it works, and nothing is as expensive as a product that doesn’t work, even the cheap ones.”
Developed by Adama, Trvior is a unique Group 4A and 7C insecticide containing the active ingredients acetamiprid and pyriproxyfen, also making it a vital tool for resistance management programs.
Acetamiprid provides rapid knockdown and pyriproxyfen offers extended residual control, while the combination also has proven to have excellent crop safety in all citrus varieties and, if applied early in the season, has little impact on beneficial and non-target insects.
“It is all about timing and we like to get in early and get it done – and we rely on it heavily,’’ Rolf says.
“We spray at 100 per cent petal fall to control the early crawler movement of sucking insects, and while we may still apply the odd corrective spray for random flights of certain lepidoptera pests, we achieve red scale and mealybug control for the rest of the season, and we don’t have to come back later,” he says.
“We like it because it is translaminar and long lasting, and, if applied properly, we get good coverage of the fruit, including access under the calyx.
“When we started applying Trivor, there was quite a bit of red scale and mealybug, but it cleaned it up in the first year.
“We do it proactively and preventatively to get the best bang for buck and we can then address any other issues later, but we are yet to have any.
“It is a very important fit for us, is very effective and contributes a hell of a lot in our endeavour to produce high quality export fruit. Our finished product is completely free of red scale and mealybug.’’
He says there have been many instances of resistance to other insecticides in the industry over the years and in order to protect current effective products, it is crucial to apply at the proper coverage.
“We cannot afford the build-up of resistant insect populations due to poor coverage – that is how you destroy good chemistry.
“Many people are under the impression that cheap alternative, old chemistry products work well on red scale and mealybug because these pests appear on the label, whereas in reality, since the time of registration, insects may already have developed resistance, rendering the products much less effective.’’
Rolf says they found Trivor to be highly compatible and had successfully mixed it with azoxystrobin and gibberellic acid, as well as other products.
He says the insecticide had not been used widely in their region and they were initially cautioned over its use within the industry, however after two years of successful applications, without any pest repercussions, their strategy was now also being embraced by other citrus growers.
