# Anyone that has an explanation?



## Bjorn (Mar 8, 2013)

Can anyone tell me what this is?




confused:


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## Secundino (Mar 8, 2013)

How does the leaf look like underneath?


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## Bjorn (Mar 8, 2013)

I think it's through but not spreading. looks like rust.


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## TyroneGenade (Mar 8, 2013)

Is that an alba philippinense? Had the same problem on mine. Seems to be some sort of bacterial rot. When I pop the leaf so it can get some air the rot stops. This isn't a fast spreading rot though...


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## Dido (Mar 8, 2013)

Have on one plant the same but looks like it is since a long time.


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## Bjorn (Mar 8, 2013)

No, its on my sanderianum that is about to bloom now. Only this leaf and does not spread. Rust??? Can it be iron? I think Xavier wrote something like that a long time ago (in the days he was Sanderianum)


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## cnycharles (Mar 8, 2013)

I think rusts are usually in scattered spots. these seem to be in an area mostly where the leaf was crinkled and there was a secondary infection.


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## NYEric (Mar 8, 2013)

That does not look like rust, looks like infection or mechanical damage to me.  Good luck.


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## Rick (Mar 8, 2013)

Almost like a burn at a break or crack.

This seems very fast.


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## gonewild (Mar 8, 2013)

Rusts generally are powdery and look like "rust" on iron.

This looks like the result of a physical damage. Perhaps like Rick said a burn or from some minute insect chewing. If it's not spreading it probably is not infected.


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## Bjorn (Mar 8, 2013)

gonewild said:


> Rusts generally are powdery and look like "rust" on iron.
> 
> This looks like the result of a physical damage. Perhaps like Rick said a burn or from some minute insect chewing. If it's not spreading it probably is not infected.



Ok, see I have phrased it poorly; with rust I meant rust on iron. Could be some insect, damage, cell collapse or similar, but it does apparently not spread. Have had it for at least half a year without much change.


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## gonewild (Mar 8, 2013)

Bjorn said:


> Ok, see I have phrased it poorly; with rust I meant rust on iron. Could be some insect, damage, cell collapse or similar, but it does apparently not spread. Have had it for at least half a year without much change.



OH yes you used the word rust to describe what it looks like (and it does).
"Rust" is a fungal disease that attacks plants and looks like rust. 

Like this...


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## Brabantia (Mar 8, 2013)

It seems to me that it is the same inconvenience as that shown by Stone this week. When I have this type of infection I apply by means of a small brush the emulsion obtained by mixing 1gr of Dithane and 1 gr of Aliette for 1 liter on the affected parts of the leaves. Roth (Xavier) has already spoken about this very general-purpose mixture to control fungal problems.
Dithane is a commercial name for mancozeb and Aliette is fosethyl Al.


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## Stone (Mar 8, 2013)

Brabantia said:


> > It seems to me that it is the same inconvenience as that shown by Stone this week.
> 
> 
> I don't think its the same


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## Rick (Mar 8, 2013)

Bjorn said:


> Have had it for at least half a year without much change.



I thought this just popped up and was spreading!

I don't know. Sometimes I see stuff like this in the winter. Condensed water drips down off a plant above or the GH roof, and then I get some local marks of leaves. 

The most prominent place is the corner near my propane heater. Maybe there's a gas/exhaust fume reacting with condensed water on leaves to cause local chemical burning????


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