black spot on catt - is it doomed?

[grasshopper]

This catt is potted in s/h and grew 2 new pbulbs last summer. I try very hard not to splash water on the pbulbs when I water, but I noticed today these black spots on one of the pbulbs. I had not peeled off the papery sheath from the pbulb, which someone told me is a good idea to do since they absorb the water and can lead to rot. (I peeled it off today when I noticed the black spots.) What are your thoughts? Rot? Something worse? Currently, it's only affecting this one pbulb, but there is a spot on the leaf on the adjacent pbulb. What should I do?

[King_of_orchid_growing:)]

No, it isn't doomed.

That's the short answer.

And this is also a bump so that others may answer the question.

[johnblagg]

Is the black actually into the Pb on the one with most black ?

[grasshopper]

Yes it is. The pbulb is not completely black, but it's splotchy near the top of it.

[johnblagg]

That sounds like a bacterial rot ...I hate to say it but I would take that growth off just above the eye at the base ....

[grasshopper]

I was afraid of that. Bummer. Is there anything I can do in the future as a preventative measure (other than being super careful when I water)?

[johnblagg]

I would get some physan 20 and use it once a month.

I had the same sort of problems ...not quite as bad but would lose the new leaf due to the black crud appearing right at the point the leaf joins the pb ....bought some physan 20 on amazon.com and started a preventitive program of once monthly treatment ...much better since then.

I did have a few times I did remove the new growth on one plant because of this and that plant eventually had to be destroyed because nothing I did seemed to help .....if I had physan at that point in time I might still have that plant ....lol the one major floofy purple I started with as a 2 to 3 year from bloom plant ...it was one of three I bought to start out with in catts and the only dark purple floofy one out of the starter collection....

[Pilot]

Originally Posted by johnblagg

I would get some physan 20 and use it once a month.

Would Physan 20 really do anything for a bacteria issue? Maybe I'm mistaking it for something else, but I thought Physan 20 was an algaecide and virucide.

Although from the manufacturers site...

PHYSAN 20™ is a broad range disinfectant, fungicide, virucide, and algaecide which effectively controls a wide variety of pathogens on hard surfaces and plants. Its applications include greenhouses; hard surfaces; lawn and turfgrass; seedlings and cut flowers; decorative fountains, pools and birdbaths; and plants.

Never says explicitly bactericide but maybe that's implied with the fungicide?

I'm trying to understand because I have a catt with a similar issue and didn't think to use physan 20 on it.

[BobInBonita]

Physan is a quaternary ammonia compound.

Wikipedia says this about quats in general:
"Quaternary ammonium compounds ("quats"), such as benzalkonium chloride, are a large group of related compounds. Some concentrated formulations have been shown to be effective low level disinfectants. Typically quats do NOT exhibit efficacy against difficult to kill non-enveloped viruses such as Norovirus, Rotavirus or Polio. Newer synergous, low alcohol formulations are highly effective broad spectrum disinfectants with quick contact times (3–5 minutes) against bacteria, enveloped viruses, Pathogenic Fungi and Mycobacteria. Unfortunately, the addition of alcohol or solvents to quat based disinfectant formulas results in the products drying much more quickly on the applied surface which could lead to ineffective or incomplete disinfection. Quats are biocides which also kill algae and are used as an additive in large-scale industrial water systems to minimize undesired biological growth."

When I worked in the food industry before retirement, quats were generally recognized as effective against many, but not all bacteria and fungi. Since only a few quats were approved for food equipment use, it is quite possible that some of the stronger quats simply couldn't be used in food plants.

We used to rotate sanitizing agents to assure that we did not build up a population of the more resistant (to any particular treatment) bacteria and fungi.

Physan has been effective for many as a general sanitizer, and for treatment of some plant infections. A manufacturer has a difficult legal position to make a label claim for a product. Many times products are found to be effective, but if the manufacturer doesn't have enough documentation to convince the government, they can't make the claim. With plant infections, it is even more difficult because a sanitizer is a surface disinfectant. If the problem is deep seated it is more difficult to treat and will probably require repetitive treatments - since the quats aren't systemic antibioticvs that "get into" the plant.

I would use it on your catt, because although not guaranteed, it is better than not treating a problem at all. Sometimes you can't tell whether a problem is bacterial or fungal and you just have to perform surgery or try something. Just make sure you dilute according to directions.

Best of luck. Keep us posted with either success or failure since we all learn.

[RobS]

Are the spots hard or soft to the touch. If they are hard they might be stable and no action is required I have several plants that have some spots and they are fine.. If they are soft and increasing in size you definatly need to do something.