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26-03-2026 15:31

Ã…ke Widgren Ã…ke Widgren

Hello,I found this one in October last year, on r

31-03-2026 16:20

Mlcoch Patrik Mlcoch Patrik

Hello, Please about help with determination. On

31-03-2026 08:19

Bernard CLESSE Bernard CLESSE

Bonjour à toutes et tous,Pourriez-vous m'aider à

30-03-2026 12:18

Sylvie Le Goff

BonjourRécolté sur la base de Pteridium aquilinu

30-03-2026 12:03

William Slosse William Slosse

Hello all,On 27/03/26, in Kraaiveld in Wingene (Be

25-03-2026 10:35

Hulda Caroline Holte

Hello,I collected this species growing on a dead b

28-03-2026 17:41

Louis DENY

Bonjour forum,Mollisia trouvée sur tige de Molini

30-03-2026 09:53

Yanick BOULANGER

BonjourVoici des petites fructifications poilues s

27-03-2026 10:47

Ã…ge Oterhals

I have tentatively identified this Stictis to S. f

28-03-2026 07:55

Marc Detollenaere Marc Detollenaere

Hello everybody,Yesterday I found a number of whit

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Peziza blueing
Malcolm Greaves, 17-06-2016 00:04
Malcolm  GreavesCan anyone tell me if it is normal for the blueing of the ascus tip to only last a very short time. I have what I think is Peziza vesiculosa from soil in the garden and the blue only lasted a few minutes. These were taken only a few minutes apart
Thanks
Mal
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Hans-Otto Baral, 17-06-2016 07:24
Hans-Otto Baral
Re : Peziza blueing
I am not sure why your photo has such a red tone. Which reagents did you apply, Melzer or Lugol? It is necessary to see the yellow colour of iodine in order to say something. For instance if you add KOH, the reaction logically disappears.
Zotto
Malcolm Greaves, 17-06-2016 10:33
Malcolm  Greaves
Re : Peziza blueing
Hi Zotto
It was a bit of poor setup of the camera software. I will try and get some more representative photos today. Both the photos were in Lugol.
Mal
Now attached. Not perfect but much more representative.
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Hans-Otto Baral, 17-06-2016 10:52
Hans-Otto Baral
Re : Peziza blueing
The phenomenon exists that higher concentrations of Lugol suppress the blue reaction. this is some kind of hemiamyloid, which is in fact a change to a dirty rid-brown. I am not sure if this is the case here. You can easily test this by adding more Lugol so that the ascoplasm gets distinctly stained.

You can also test KOH-pretreatment. After washing with water you can repeat the test, the effect should then be absent.
Malcolm Greaves, 17-06-2016 10:55
Malcolm  Greaves
Re : Peziza blueing
Didn't seem to fade with Meltzers.
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