Suspicious spots on Paphs

[Bjorn]

Ihave looked a bit into the web, but have not found much on the topic, so I cling to this idea without proof.but it seems more and more likely to me that traditional feeding regimes jave been one important promotor of many of the problems seen in paph.(orchid) culture.
Also the more I look into these things, the more I get convinced that mcuh of the effect seen with eg kelp is due to the chelating action of the relatively high amount of aminoacids it contains. Those chelates are seemingly important for the transport through the cell membranes and i to the roots. Next step might be adding micros to kelp juice and feed with that??

 

[gonewild]

Ihave looked a bit into the web, but have not found much on the topic, so I cling to this idea without proof.but it seems more and more likely to me that traditional feeding regimes jave been one important promotor of many of the problems seen in paph.(orchid) culture.
Also the more I look into these things, the more I get convinced that mcuh of the effect seen with eg kelp is due to the chelating action of the relatively high amount of aminoacids it contains. Those chelates are seemingly important for the transport through the cell membranes and i to the roots. Next step might be adding micros to kelp juice and feed with that??

I agree completely, this is the track I have been on. I don't know much about amino acids but I know that lichens do excrete amino acids among other compounds. Perhaps other organisms produce chelate like compounds that are not even yet identified and these compounds are what orchids derive the nutrients from in Nature. Dissolved nutrients as salts obviously supply nutrients but perhaps these salts in our normal high doses cause reactions and issues that look like a disease but is not caused by a pathogen. The theory that Roth gives about Iron fits this very well. And theories like this begin to explain symptoms like these strange spots on the Paph.

 

[Bjorn]

Think we are in line there.
B

 

[orcoholic]

Orthene 97 wettable powder is now labeled as acephate 97 and is a very inexpensive, albeit smelly, insecticide. It is an effective contact insecticied with no systemic or translaminar action.

 

[Happypaphy7]

Downy mildew? "leaves might look yellow at first, but a brownish-black mold is then likely to appear on the underside." according to http://www.dispatch.com/content/sto...10/07/11/ohio-basil-threatened-by-mildew.html

See http://en.wikipedia.org/wiki/Downy_mildew

The alternative is Rust, which is a virus... but lets go forward with the fungal infection hypothesis for now.

The article says and shows pictures that it is black mold, which grows on the surface of the leaf underside.
This dark brown spotting issues on the underside of GN and Delrosi we're talking about is not mold but rather they appear inside the leaf tissue.
If you look very closely, these marks have almost black center which is very very very small, and this center is surrounded by brown area.
I wiped them but they don't come off. They are not mold.

 

[Happypaphy7]

Found it!
http://www.slippertalk.com/forum/showthread.php?t=23168&highlight=iron&page=3
Not exactly as in the Pictures but a problem might have different manifestations. So perhaps? One last question, the soil that the plant grows in, what is the pH?

Most of the pictures on that thread are gone and the ones I do see have marks that are vastly different than the ones we're talking about here.

 

[The Mutant]

Found it!
http://www.slippertalk.com/forum/showthread.php?t=23168&highlight=iron&page=3
Not exactly as in the Pictures but a problem might have different manifestations. So perhaps? One last question, the soil that the plant grows in, what is the pH?

It's alkaline apparently, so I guess mites and/or rust fungus are the most possible alternatives? Should I tell her to treat with miticide and fungicide?

 

[mrhappyrotter]

I'm just going to say it (haven't read the whole thread yet), but Neem is my latest go-to weapon, and while it has its cons, I'm starting to like it.

So, I guess what I'm saying is, if you have spots of any kind, consider adding a routine & preventative Neem routine to your collection. From my (admittedly anecdotal) experience, it seems to be able to prevent the spread of bacterial and fungal pathogens. It's also effective against leaf-living pests.

Just be mindful that not all plants tolerate treatment with Neem, so do your research first. I'm confident its safe on slippers, but there are reports that it can cause issues with dendrobiums and other plants in general.

 

[The Mutant]

I'm just going to say it (haven't read the whole thread yet), but Neem is my latest go-to weapon, and while it has its cons, I'm starting to like it.

So, I guess what I'm saying is, if you have spots of any kind, consider adding a routine & preventative Neem routine to your collection. From my (admittedly anecdotal) experience, it seems to be able to prevent the spread of bacterial and fungal pathogens. It's also effective against leaf-living pests.

Just be mindful that not all plants tolerate treatment with Neem, so do your research first. I'm confident its safe on slippers, but there are reports that it can cause issues with dendrobiums and other plants in general.

The funny thing is that I recently purchased Neem oil and have used it on two Paphs recently (the lowii that showed sign of having had unwanted guests again for example). Since apparently my culture isn't optimal, I need to add some sort of preventative treatment and also try to improve my culture as much as possible.

But my issues with my Paphs is not what this thread is about (talking to myself here), but my fellow forum member. I still don't know what to recommend that she should do, except treating against mites and fungi are probably good ideas.