Almond enterprises are increasingly recognising they have to be particularly strategic with orchard fungicide applications to ensure their produce continues to meet export destination requirements.

Graeme Judd, senior agronomist with EE Muir and Sons, said the ban on various fungicides used in export almond production was providing challenges for the industry.

“With a lot of our exports to the EU, there are a number of products that we can’t use anymore,’’ Mr Judd said.

“Many of them are also multisite products, like Captan, mancozeb and chlorothalonil. They have been quite widely used in cover sprays, but there are no MRLs (maximum residue limits) in place for them anymore with the EU.

“The EU represents about 34 per cent of the Australian almond industry, so it’s important to keep it and, therefore, we need look at alternative chemistry to continue to supply these markets. We have to look at (both) new and established molecules to control disease going forward and we have to be very strategic with our applications and particularly the timing of applications.’’

Mr Judd said some of the key diseases to target in almonds included shot-hole, brown rot, blossom blight, rust, scab and anthracnose, and the export product restrictions were placing pressure on remaining chemistry, such as Group 11 fungicides.

“By losing a lot of the multisite fungicides, it is placing more pressure on the Group 11s, which need the multisites to prolong their life, otherwise disease resistance builds up to them.’

“The Group 11s are very effective, but from a disease management perspective, you can only use three in a season, and you can’t exceed 2 litres per hectare per season.’’

Mr Judd said a new, alternative fungicide offering Group 9 (cyprodinil) chemistry that was proving to be a strong option around bloom in orchards was Solaris, from ADAMA Australia.

“Where growers have been using two Group 11s around budburst and bloom, the use of Solaris during this timing can free-up a Group 11 to be used later in the season – around October for suppression of anthracnose – and this will help prolong the life of Group 11 chemistry.’’

Cyprodinil, the only mode of action of its kind for use in almonds that assists with resistance management, is a systemic compound that is taken up into the cuticle and waxy layers of leaves and fruit and is locally redistributed. It is highly active against brown rot, blossom blight, rust and shot-hole.

Mr Judd said it offered flexibility as a Group 9 fungicide and could be applied from pink bud through to before petal fall and shuck fall, however it’s best fit was early bloom.

“Some growers are using it in conjunction with Group 7 and 11s and that is a good mix – 7, 11 and 9.’’

“There can be six to nine fungicide applications in a season depending on the region and budgets, and like all good fungicide programs, it’s best to use as many groups as possible to avoid chemical resistance. Always try to alternate your groups.

“Applying early in the season, around bloom, hits on the old saying: ‘the more you get right early in the season, the less problems you’ll have later in the season’.’’

He said another strong benefit with Solaris, which is also an easy-to-handle emulsifiable concentrate formulation, is its soft activity on beneficial insects, particularly bee populations during pollination in almond orchards.

“The number of bees that get moved into almond orchards from interstate at bloom time is phenomenal and to please beekeepers and the bees, you have to be selective with what you use at pollination and spray at night when bees aren’t foraging. Products such as Solaris are quite safe to use around bees at flowering,’’ Mr Judd said.

ADAMA Australia southern market development manager – horticulture, Daniel Polson said its high safety to pollinators made Solaris a good fit for almond production, which relied on high percentage fruit-set to achieve required yields.

“It’s safe to bees and other beneficial species, including predatory wasps, ladybirds and omnivorous anthocorid bugs, which prey on pests such as aphids, mites and moth larvae during early spring.”