Being a major producer of avocados in southern Queensland, Sunnyspot Farms needs to be right onto disease management to protect their crops. It’s especially important, according to farm manager Tyson Cross because avocados are such a ‘sensitive’ tree.

“Avocados tend to get a few pests and some disease, mainly stem end rot, anthracnose and phytophthora, and often in the cooler winter months,” he said.

“Anthracnose particularly is a major problem and so we have a disease management program that we run with all year round. If we didn't run an effective program to control anthracnose and stem end rot, the fruit may not be viable for picking, so we can’t sell it, meaning it'll stay on the tree and our profits go downhill.”

Based in Ravensbourne, Sunnyspot Farms consists of three irrigated properties, totalling 45 hectares of avocado trees. Traditionally they have tackled disease by applying copper once a month – or more in wet weather, and then putting on two applications of another fungicide prior to harvesting.

In 2021, the team at Sunnyspot Farms trialled Luna Sensation, a broad-spectrum fungicide from Bayer, registered for the control of anthracnose and stem end rot in avocados. Mr Cross says the unique combination of fluopyram, a novel chemical within the ‘SDHI’ family, and trifloxystrobin was attractive.

“We decided to give Luna Sensation a go to get new chemistry in our disease management program rotation, and it’s fitted in very easily,” he said.

The Sunnyspot team applies the first application of Luna Sensation around early October, at the start of fruit set on the trees. The second application is then applied just prior to harvest, with the flexibility around application timing providing a huge benefit.

“The beauty of the second application of Luna Sensation is it's only got a three-day withholding period versus the older chemistries with a seven day plus withholding period. So, it enables us to get the product on, and then pick it not long after,” Mr Cross said.

“The three-day withholding period is a big thing. We can apply Luna Sensation and potentially still get our fruit off before an adverse weather event, versus the older chemistry where we're having to wait longer.”

Luna Sensation is also compatible with a number of different insecticides, further increasing on-farm efficiency, with Mr Cross and his team saying they find the product easy to handle in terms of both mixing and application.

They’ve also found a good fit in the program for Serenade Opti, an organically certified (ACO and OMRI) biofungicide from Bayer.

“From flowering through to harvest, our disease management rotation includes copper, Serenade Opti, Amistar, and now we have Luna Sensation, which is great because it gives us another weapon in our armoury,” Mr Cross said.

Local territory business manager for Bayer based in Toowoomba, Carmen Brown, says Serenade Opti is used as an extra tool in avocados to treat stem end rot and anthracnose, as part of a program approach.

“Serenade Opti can be applied as early as flowering, and then we can rotate it with other groups of chemistry throughout the season, right through to harvest.

“The benefits of including Serenade Opti in the program is it's a softer option, so it can be applied over flowering while bees are foraging,” she said.

Mr Cross says Serenade Opti has been a welcome addition to their disease management program. “I've found it's been a lot softer on the trees compared to copper, so it’s a crucial part of our rotation.

“Serenade Opti and Luna Sensation also fit well within our integrated pest management program. They're compatible with nearly all the products we use.”

While Luna Sensation and Serenade Opti are both performing well for growers, the trial work hasn’t stopped, with plenty of work being done by Bayer across various crops.

“From our trial work locally, what we have seen in avocados in particular is extended shelf life by using Luna Sensation at that last application,” Ms Brown said.

“Growers can also expect to see better fruit quality when using Luna Sensation in a program and it provides growers another tool in resistance management.

“We're also currently trialling Serenade SOIL ACTIV, a future new high-loaded soil ameliorant at the root flush stage.

“It has a fast colonisation to the root zone, helping to change the soil resources to a plant-ready form, resulting in improved root architecture, better utilisation of the nutrients we put on, and improved plant growth and yields,” Ms Brown said.