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29-09-2022 20:26

Elisabeth Stöckli

Bonsoir, Trouvé à 2'500 m (prairie alpine), tai

05-10-2022 14:35

Viktorie Halasu Viktorie Halasu

Hello,I've found here a Hypoxylon (or Hypomontagne

04-10-2022 18:38

Juuso Äikäs

These little brown, hairy apos were growing on a d

01-10-2022 11:54

DirkW DirkW

chers collègues, anyone out there who could send

05-10-2022 16:09

JEAN CABALION

Bonjour, Qui peut me renseigner sur ce Podostroma

24-10-2021 21:50

Robin Isaksson Robin Isaksson

Hi,Found on Andreaea rupestris sweden.ascomata bl

29-09-2022 17:25

Juuso Äikäs

A finding from a couple days ago: a few white Hyme

29-09-2022 13:34

Marja Pennanen

Dear colleagues, a couple of days ago I found the

13-12-2014 21:47

Rubén Martínez-Gil Rubén Martínez-Gil

Hola a todos. Subo unas imágenes de un disco neg

26-09-2022 15:31

Zuzana Sochorová (Egertová) Zuzana Sochorová (Egertová)

Hello,please, can this be something else than Hypo

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Gnomoniaceae on Betula leaves
Marcus Yeo, 15-08-2022 20:36
While in NE Scotland recently I made a couple of collections of Gnomoniaceae on fallen leaves of Betula (probably Betula pubescens). I was expecting them to be Ophiognomonia ischnostyla but the ascospores seem wrong for this species.

Details are as follows. Perithecia fully immersed; ca 600 µm diam.; with necks up to ca 1500 µm. Asci ca 45-55 x 12-16 µm; with prominent apical ring. Ascospores hyaline; fusiform; 1 -septate (septum median); constricted at septum; 22-25 x 3.5-4 µm; no appendages seen.

The ascospores seem to be too large for O. ischnostyla. For example, Sogonov et al. (2008) Studies in Mycology 62:1-79 give dimensions of (12.5–)13.5–15.5(–18.5) × (1.5–)2(–2.5) µm for O. ischnostyla. This corresponds with my experience of the species in the UK.

Monod's monograph of Gnomoniaceae contains Gnomonia betulina (synonym G. campylostyla) with ascospores 13-23 x 2.5-5 µm, which would fit with my collections. However, the spores are described as having appendages. G. betulina and/or G. campylostyla don't seem to be treated in Sogonov et al or in any other recent papers on Gnomoniaceae.

I'd be grateful for any help anyone can provide.

Thanks

Marcus
  • message #73697
  • message #73697
  • message #73697
  • message #73697
Alain GARDIENNET, 16-08-2022 10:53
Alain GARDIENNET
Re : Gnomoniaceae on Betula leaves
Hi Marcus, 
I observed for some species, that appendages could be sometimes present, or sometimes absent. Monod did same remarks :Gnomonia emarginata, one species close to G. betulina, is a good example. Perhaps is this more common at the end of maturity ?
So I think you're  probably right.
Monod's work is the most complete for european species, and even if Sogonov and Walker have greatly advanced our knowledge of the Gnomoniaceae, and in particular the genus Ophignomonia, it may still be incomplete, especially as regards the european species. Therefore, Monod's work remains the best reference for the latter, and deserves to be completed by new studies. Donald Walker is no longer working on the Gnomoniaceae, there are not enough mycologists!
Gnomonia betulina is probably a poor known species ( a bit like Gnomonia kisslingii ion Quercus leaves). It would merit molecular studies. Please keep material in herbarium.
Best wishes,
Alain


 

Marcus Yeo, 16-08-2022 11:57
Re : Gnomoniaceae on Betula leaves
Alain

Thank you for your response - that is very helpful.

I'm hoping to get the material into culture and get DNA analysis done.

Regards

Marcus


Paul Cannon, 16-08-2022 12:41
Re : Gnomoniaceae on Betula leaves
I agree with Alain, presence of appendages in this group can be irregular. There are ITS sequences available of both G. betulina and G. emarginata contributed by the Sogonov group and blasting suggests that they are close but distinguishable. G. emarginata must also be a possible ID, I suspect that mounting media may influence spore dimensions (particularly width in elongated thin-walled spores). Hope the sequencing works well...

Best wishes

Paul
Lothar Krieglsteiner, 31-08-2022 10:35
Lothar Krieglsteiner
Re : Gnomoniaceae on Betula leaves
Hello together,
I just tried to get the Monod paper via Internet but failed. Does somebody have? I would be interested.
Thanks and regards, Lothar
Norbert Heine, 31-08-2022 20:13
Norbert Heine
Re : Gnomoniaceae on Betula leaves
Lothar Krieglsteiner, 31-08-2022 20:18
Lothar Krieglsteiner
Re : Gnomoniaceae on Betula leaves
Hallo Nobi,
vielen Dank für den Link - klasse!
LG von Lothar