Accès membres

Mot de passe perdu? S'inscrire

04-03-2009 00:13

Andreas Gminder Andreas Gminder

Bonsoir collègues, un membre d'un forum anglai

02-03-2009 20:07

Enrique Rubio Enrique Rubio

Could be this fungus? On Rubus sp. old stems. Asco

02-03-2009 09:22

Alain GARDIENNET Alain GARDIENNET

Je sais ce que vous allez deviner, l'Alain il a tr

01-03-2009 21:31

VASILEIOS KAOUNAS

Found 01-03-09, Korinthia Greece, hypogeous in hum

01-03-2009 10:10

Enrique Rubio Enrique Rubio

Cher amis: Je vous prie une opinion sur cette Ham

01-03-2009 02:23

Roland Labbé

Bonjour ! Encore besoin d'aide pour ce Disco ja

28-02-2009 22:12

Yannick Mourgues Yannick Mourgues

Bonsoir à tous. Sur une branche morte de Tilia

28-02-2009 18:20

BELLIDO BERMEJO FERNANDO

Hola a todos, es el primer mensaje que envío, me

27-02-2009 21:00

Yannick Mourgues Yannick Mourgues

Bonsoir. Le genre Nectriopsis fait-il parti des L

27-02-2009 05:29

Roland Labbé

Voici une planche d'un minuscule ascome avec appen

« < 1428 1429 1430 1431 1432 > »
Nectria sur Diatryope stigma
Andreas Gminder, 04-03-2009 00:13
Andreas GminderBonsoir collègues,

un membre d'un forum anglaise m'a envoié le question suivante sur l'identité d'une Nectria poussant sur Diatrype stigma. C'est peut-être pas N. episphaeria, parce-que les spores sont assez trop grand. Je lui a promis de presenté son trouvaille ici:
_____

I found a Nectria on Diatrype stigma (confirmed by microscopy) and the spores are quite wrong for N. episphaeria. Photo here:
http://www.leifgoodwin.co.uk/Fungi/0__DSC6705%20Nectria%20episphaeria.jpg

Spores:
http://www.leifgoodwin.co.uk/Fungi/1__DSC6719%20Nectria%20spores.jpg

Here is a squash of an ascocarp with some asci:
http://www.leifgoodwin.co.uk/Fungi/_DSC6907%20Asci.jpg

The spores in the collection were significantly larger than expected: 14x6, 13x7, 15x6, 13x7, 13x6, 1 septa, 2 drops, smooth, ellipsoidal to spindle shaped.

For this reason the identity of the collection is unknown.

I don't suppose you have any suggestions? I am aware of Nectria with such spores, but not on Diatrype!

Thanks. Leif
_____

best regards,
Andreas
Gary Samuels, 04-03-2009 14:39
Re:Nectria sur Diatryope stigma
Despite the somewhat large ascospores I would still think of Cosmospora episphaeria for this fungus. We would want to know the anamorph. Understanding of most Cosmospora species is imperfect; we need more collections and more cultures.
Leif Goodwin, 04-03-2009 18:58
Re:Nectria sur Diatryope stigma
Merci Andreas. Je viens de recevoir mon mot de passe pour le forum.

En effet mon problem est que je n'ai qu'une seule livre d'identification pour ces especes i.e. The Fungi of Switzerland Volume 1. Selon cette ouevre, les spores de Nectria episphaeria sont beaucoup plus petits que ceux de l'espece que j'ai trouve (7-11)x(4.5-5), et ils sont supposes d'etre rugueux et constricte. Ceux que j'ai examines sont lisses, et a peine constrictes.

Finalement, est'ce qu'on peut me recommande une livre specialise sur les especes?
Gary Samuels, 04-03-2009 19:16
Re:Nectria sur Diatryope stigma
Two publications deal with Cosmospora:
1991. Samuels, G.J., A. Y. Rossman, R. L. Lowen, & C. T. Rogerson. A synopsis of Nectria subg. Dialonectria. Mycological Papers 164: 1-47.

1999. Rossman, AY, Samuels, GJ, Rogerson, CT, Lowen, R. Genera of Bionectriaceae, Hypocreaceae and Nectriaceae (Hypocreales, Ascomycetes). Stud. Mycol. 42: 1—248.

Our group at USDA-Beltsville is engaged in a study of Nectria, including Cosmospora. We would be very happy to have fresh collectgions of any 'red' Nectria/Cosmospora. In the case of Cosomospora, it is critical to be able to study the anamorph and to know the identity of the substratum. Your fungus looks like C. episphaeria but, of course, it could be something different. We simply do not have enough verified collections of Episphaeria to be able to define accurately the species limits.
Leif Goodwin, 04-03-2009 19:29
Re:Nectria sur Diatryope stigma
Gary, thank you very much. I will class this as N. episphaeria in my records and comment on the unusually large spores. I would happily send you the specimens though I am not sure it is worth it or if customs would allow 'plant' material. I took maybe 5mm x 5mm of Diatrype with some Nectria on, and scraped some Nectria off to study. There are perhaps 10+ red blobs still on the Diatrype.

Leif
Gary Samuels, 04-03-2009 19:40
Re:Nectria sur Diatryope stigma
Leif
We would like to have this collection if it is still fresh (not dried by heat). Because of the largish ascospores it is quite interesting. If you will contact me via email, I will arrange to send a permit to you. gary.samuels@ars.usda.gov

thanks much
gary
Andreas Gminder, 04-03-2009 20:07
Andreas Gminder
Re:Nectria sur Diatryope stigma
Bonjour,

thank you also from my side to Gary for his comments, which are also interesting to me. Up to now - as I have to admit somewhat ashamed - I have determined Nectria episphaeria macroscopically or better ecologically and have not verified every collection by microscopy. Seems as if I should change that ....

best regards,
Andreas
Gary Samuels, 04-03-2009 21:09
Re:Nectria sur Diatryope stigma
'Nectria episphaeria' is, perhaps logically, the most common name applied to 'little red nectria' Probably in most cases the name is incorrectly applied. There is a wealth of species that grow on other pyrenomycetes and that have little red perithecia. I tried to distinguish some of them in the Stud Mycol article cited earlier. What we need is good collections from identified hosts; in tnis way we can test host specificity, anamorphs and molecular phylogenetics. If Cosmospora is typical of other species-rich groups, phylogenetic anlaysis will reveal far more species than we have ever suspected. A postdoctoral fellow working with us now has found that Nectria cinnabarina, a name that we used to think we could be comfortable with, actually comprises two or more species.