moumou wrote:Beyond the natural processes of evolution, including human impact, and when all the fingerpointing is finished...
What can we as growers do at home to 'control' this pathogen and minimise impacts to our bonsai, garden plants and local environs?
http://permits.apvma.gov.au/PER12156.PDF
Use triforine if you have Myrtle Rust. Then rotate other fungicides but wait the recommended time to pass, as well as continuing to use triforine, so as not to allow an immunity to build up.
Do not spray the bonsai with triforine on a really hot day (over 28 deg probably wouldn't spray, or at worst spray in the evening). I lost a few young trees from this.
I would use half strength, then in about 3 weeks time use full strength. Depending on how healthy your tree is.
FYI - Use Triforine as half strength on Angophora, then build up strength as time goes by. This was the species that seemed to have the least tolerance to Triforine.
EDIT (just from my experience with MR) -
For using TRIFORINE:
Angophora floribunda is not that tolerant to triforine.
Angophora bakeri had no problems
Angophora hispida had no problems
So far, it seems all my callistemon have no problems to triforine, and in fact appear to be the best at resisting the Myrtle Rust.
Eucalyptus have no problems with triforine
Kunzea had no problems with triforine
All my Melaleuca were affected quite a bit by triforine.
For Myrtle Rust:
Melaleuca were affected the worst by the Myrtle Rust
Eucs had varying degrees of illness depending on the species. (the best species of what I have would be Euc. robusta / saligna to tolerate Myrtle Rust)
My Angophora species weren't too badly affected by the myrtle rust.
My Callistemons actually seem to power through it. The rust just doesn't seem to be able to take hold that well on them. But I only have 3 varieties: violaceous / linearis / pinifolius
Kunzea don't do well from the Myrtle Rust
Leptospermum seem to have different tolerances depending on the species. Scoparium is not so good, but petersonii has good tolerance.
But any seedlings of any of the different genus above or just young material (less than 2 years), was greatly affected by myrtle rust.
And on a side note:
If you have Myrtle Rust spores in your collection, then move anything from the Myrtaceae family to full sun, or maximise the amount of sun it gets. Full sun will greatly increase the ability for the tree to resist the fungal disease. Don't mist the trees! It helps to water the soil when the tree needs it and not the foliage / trunk. However, this is next to impossible for time constraints if you own a lot of bonsai / trees.
Until we control Global warming MR will continue. Its probably something that has been around but now the conditions favour Its survival and it thives in wet/humid conditions. Like the Pine Beetle devastating old Pine growth in the States the beetles were always there the cold controlled their numbers now just 2 degrees warmer and they are killing forests.. 
