Opuntia disease - what is this?

[BennieAnTheJets]

Got a set of different Opuntia pads and some of them are doing this (below). What the heck is that? Lost a few to this and now more of them are starting. Is there something I can do to protect the rest?

Thanks!

Opuntia disease.jpg (111.14 KiB) Viewed 731 times

[BennieAnTheJets]

I guess, obviously, I need to remove them. Was waiting for them to grow a new pad so I would not lose the variety - but I suppose I should do that in quarantine. Duh! Still, if you know what this is, would appreciate your input!

[hegar]

This is the "most outstanding" picture I have yet to see of a severe infection by the coelomcyete fungus Phyllosticta concava.
I just recently posted a digital image of this pathogen, which you can find near the top of this page (sticky post) with the name "Some fungal Diseases".

Harald

[BennieAnTheJets]

Thanks, Harald!

I looked at the pinned post you so kindly provided on fungal diseases. Did not see solutions, other than one person talking about treating with sulfur but I would have no idea how. Just powder it on dry? Make it into a paste and smear it on?

Any help much appreciated.

These fungi seem to stay on one pad and the pad still puts out new pads. Would you throw them out anyway to avoid spores, or whatever fungi use to propagate, to fly to other cacti? Throw it out would mean into the trash and to the landfill in a closed bag, I suppose, not to the compost pile in that case.

[teo]

I use something called 'Kumulus DF' - a sulphur(ic) powder diluted in water for fungal problems (actually for mildew)

[BennieAnTheJets]

Thank you, teo!

I have a sulfur powder. Do you think I could make a dilution? What ratio do you use?

This is what I have: https://www.amazon.com/Lilly-Miller-100 ... 310&sr=8-6

[teo]

I think about 1 tablespoon / 2 L (there should be instructions on the bottle ?)