Accès membres

Mot de passe perdu?

21-11-2025 11:52

Sepultaria arenicola

Jean-Luc Ranger

Bonjour à tous, on voit toujours 2 espèces areni

21-11-2025 10:56

Ascomycete on Humulus

Christopher Engelhardt

Christopher Engelhardt

Very small (~0,5 mm) white ascos, found yesterday

21-11-2025 10:50

Orange small asco?

Mirek Gryc

Hello Please help me identify this little asco.It

21-11-2025 10:47

FranÃ§ois FrelÃ©choux

François Freléchoux

Bonjour,Peut-être Mollisia palustris ?Trouvée su

29-06-2016 18:06

Elisabeth Stöckli

Bonjour,Trouvé sur branches mortes cortiquées de

14-11-2025 16:26

Small species on Cytisus scoparius

Marian Jagers

Marian Jagers

Hello everyone, On dead wood of Cytisus scoparius

17-11-2025 21:46

Lachnum impudicum

Philippe PELLICIER

Bonjour,Récolté sur bois pourrissant de feuillu

20-11-2025 14:14

Unknow species on 'Juglans regia', possibly fusarium spec?

Mick Peerdeman

Found on the leaves of 'Juglans regia' in the Neth

20-11-2025 13:07

Possibly 'Ascochyta Malvae' on 'Malva sylvestris (cultivar)'?

Mick Peerdeman

In January i found these black markings on the dea

20-11-2025 12:38

Possibly 'Calonectria ilicicola' on 'ilex aquifolium'?

Mick Peerdeman

Dear all,Last week i stumbled upon a leaf of ilex

Stictis radiata sur Fallopia japonica

Bernard CLESSE, 10-01-2016 22:31

Bernard CLESSE

Bonsoir à tous,

Suite et bientôt fin de mes récoltes sur renouée du Japon. Ici je pense à Stictis radiata, d'abord parce que les apothécies sont nettement plus petites (max. 0,3 mm de diamètre) que chez Stictis stellata (diamètre parfois dépassant le mm) montré tout récemment sur Fallopia japonica toujours et que d'autre part, les spores sont ici larges de 2-2,5 mu.

Qu'en pensez-vous ?

Bernard

Hans-Otto Baral, 11-01-2016 09:42

Hans-Otto Baral

Re : Stictis radiata sur Fallopia japonica

I recommend to make images in vital state though I am quite sure that the oil content in the spores is low. Also a section showing the periphyses at the inner face of the margin would be helpful, I remember Sherwood makes a difference based on their measurements. Did you notice any iodine reaction?

Bernard CLESSE, 11-01-2016 11:00

Bernard CLESSE

Re : Stictis radiata sur Fallopia japonica

Hi Zotto,

Thanks for your message !

I will try to make a cut of apothecium but I admit that I do not know what are the periphyses. Would you possibly a drawing or a microscopic picture so that I know what I have to observe? I will try to redo pictures spores alive.
Regarding the iodine reaction, I just noticed a very slight blue color and diffuses into the ascus (especially upper half) with lugol but not a color "deep blue" suitable for this species.

Bernard

Hans-Otto Baral, 11-01-2016 11:35

Hans-Otto Baral

Re : Stictis radiata sur Fallopia japonica

If you pretreat with KOh you will get a distinct blue of the whole hymenium, without KOH the reaction is first blue the red-brown, and only at the top the hymenium is bluish.

What is meant with periphysoids (not periphyses, sorry) you can see here.

Sherwoods distinction is perhaps a bit weird, and her opinion about amyloidity may be wrong as she appears not to have understood the influence of KOH and Melzer's.

But I must admit I have no clear concept of thse two species.

Bernard CLESSE, 11-01-2016 20:56

Bernard CLESSE

Re : Stictis radiata sur Fallopia japonica

Hi Zotto,

Thank you for your explanations !

Here are some new pictures :

a) hymenium+KOH+lugol : well blue !
b) ascus+lugol : dextrinoid; ascus cap : 3,5 mu thick
c) spores guttulated

What do you think about that ?

Bernard

Hans-Otto Baral, 11-01-2016 22:30

Hans-Otto Baral

Re : Stictis radiata sur Fallopia japonica

Oh look, these guttulate spores are exceptional, I don't know that from radiata or stellata. But I don't know these species well or can separate them.

A red reaction inside the ascus could be due to glycogen and would then be called dextriniod, but then it should be seen also after KOH, or in Melzer without KOH. What reacts blue after KOH (I think the ascus wall surface) must be red in IKI without KOH (hemiamyloid). See my homepage:
http://invivoveritas.de/articles/iodine-reaction-in-ascomycetes-why-is-lugols-solution-superior-to-melzers-reagent/
Fig. 2 and 5.