Fusarium solani?

[Skycat]

I just got this Phal yesterday for $1 (because Lowe's is doing this thing where they basically put the clearance plants on clearance) and I was repotting it today and found this on a rotted root



Ugh, the rest of the plant looks pretty healthy for having been grown in moss!





If the plant looked sick, I'd just toss it and not even bother with this nasty crap. Anything that's orange on a plant and not supposed to be there really freaks me out.

I've cut off the really bad root (and several more rotten roots), and I think I saw a little bit of orange stuff on another root, but I can't find it now, and I think I'm just going to leave the plant where it is for the rest of the night because there's TONS of mosquitoes and I'm not going to have any blood left if I spend any more time out there.

[katrina]

I think what you have there is a type of slime mold. Which is a type of fungus and like all other fungi...they feed on decaying matter. Makes sense that it's on the dead roots.

I would unpot and remove the all the old medium, trim the dead roots and then wash the plant (roots and all) w/a mild soapy solution....rinse and then pot up in fresh medium. You may not get all the spores but if you eliminate the conditions that caused the overgrowth of the fungus then you shouldn't have any further issues with it.

[Skycat]

Originally Posted by katrina

I think what you have there is a type of slime mold. Which is a type of fungus and like all other fungi...they feed on decaying matter. Makes sense that it's on the dead roots.

So nothing I should have to worry about spreading to my other plants? Everything I've read about fusarium is completely terrifying, so slime mold actually sounds like a huge relief (not that I'd want to keep it around anyway, of course).

[NYCorchidman]

It is a form of fusarium I believe because there was a thread on this recently.
I'm sorry I don't recall what the title was, but someone brought this orange ball thing up with photos, and some great answers followed.

If you are very old or otherwise suspect that you have a lowered immune system, this thing can even be fatal when inhaled.

So I would get rid of those orange balls.

[Vsol]

Did you save your plant? I have this same issue.

[aliceinwl]

I had a Phalaenopsis with a similar issue. The fungus set in on the roots that died following a repot (the roots were already in poor condition but weren’t quite dead so I didn’t remove them when I repotted. Since the orchid was actively growing new healthy roots and the fungus was confined to already dead tissue, I just left it alone. Once the dead roots were broken down, the fungus disappeared and the plant now has a healthy root system.

[SouthPark]

Originally Posted by NYCorchidman

It is a form of fusarium I believe because there was a thread on this recently.

NYCO --- was it this thread? Click Here

If those orange balls are truly a variety of fusarium, then from what some growers are mentioning ------ this won't necessarily go down in tears, which is nice.

Looks like flying fish roe hehehe. But on a serious note ....... at least it sounds like a recoverable condition.


Skycat ..... do you have drainage holes in that pot at all? If not, then I recommend an adequate number and size of drainage holes.

[Ray]

I'm no mycologist, but every reference I've seen about Fusarium solani suggests its growth is white and cottony, not orange balls.

[aliceinwl]

I turned up the same results as Ray during my searches. It seems slime molds come closest.

[camille1585]

There is information out there if you know what to look for. (Ascomycete) fungal taxonomy is a mess because they have different morphs, which are the sexual (telemorph) and asexual (anamorph) states of the fungus. This has led to fungi having dual nomenclature based on their morphs. Fusarium solani is one very good example, where the name corresponds to the asexual morph which leads to root and leaf sheath rot. The sexual morph of the exact same fungus is called Nectria haematococca, and forms reproductive structures in the form of red/orange balls called perithecia.

If you then google the name of the sexual form, you will probably find a lot more information. That being said, it doesn't mean that the red balls the OP sees actually are Fusarium since many other fungi make such sexual structures. I also don't know how frequently the sexual morph will develop on orchids, it could be that we never hear of it because orchids are primarily affected by the asexual one.


If you are scientifically minded, there is a nice review about the issues surrounding dual nomenclature of fungi, the reasoning behind it, and arguements for adopting a 'one fungus, one name' approach. http://www.wi.knaw.nl/images/Researc...11.00768.x.pdf