29-12-2019 17:10
Bernard CLESSE
Bonsoir à toutes et tous,Voici un petit asco blan
28-12-2019 10:59
Bernard CLESSE
Bonjour à toutes et à tous,Que pensez-vous de ce
27-12-2019 05:59
I found this two days ago on decorticated Ulmus in
28-12-2019 14:21
Edvin Johannesen
These black spheres (acervuli or pseudothecia? - n
27-12-2019 02:29
Lepista ZacariasDear all,I'm in trouble with my microscope and it
27-12-2019 02:29
Lepista ZacariasDear all,I'm in trouble with my microscope and it
25-12-2019 17:54
Valencia Lopez Francisco JavierHola a todos/asEstas supuestas pezizas estaban en
Eutypa ?
Petra Eimann,
29-12-2019 15:54
Jacques Fournier,
29-12-2019 18:28
Re : Eutypa ?
Dear Petra,
the identification of Diatrypaceae is most often challenging and requires the accurate observation of several characters, not only ascospores.
A common species on Sambucus is Peroneutypa scoparia, and ascospore dimensions fit fairly well. However the ascus shape on your photos is not typical for this species.
You need information on the ostioles and stromatal configuration. For the latter purpose a vertical section as you did would hav been much more informative if you had used a sharp razor blade. It is important to assess whether ascomata are widespread in a common stroma with separately emergent ostioles (Eutypa or Diatrype) or in small groups with convergent ostioles (Eutypella or Peroneutypa)
The apical ring of P. scoparia is relatively conspicuous for the genus and must be observed in Melzer's reagent after a 15 s pre-treatment in 3% KOH.
If you encounter problems with the vocabulary and the delimitation of genera, I suggest you to consult Rappaz' article (1987).-Taxonomie et nomenclature des Diatrypacées à asques octosporés. Mycologia Helvetica vol 2, n° 3, p. 285-648.
Good luck,
Jacques
Petra Eimann,
30-12-2019 00:22
Re : Eutypa ?
thank you very much Jacques, we will try again. Petra







