Accès membres

Mot de passe perdu? S'inscrire

09-05-2025 19:10

Enrique Rubio Enrique Rubio

Hi to everybody.This Orbilia (apos up to 0.5 mm),

09-05-2025 19:25

Viktorie Halasu Viktorie Halasu

Hello, would you please recommend me a key to gen

09-05-2025 16:01

Thomas Flammer

I found a black cushon which might eventually be 

02-05-2025 13:29

Isabelle Charissou

Bonjour, j'aimerais savoir s'il y a eu des public

06-05-2025 13:37

Thomas Flammer

Munk, Anders (1953). The System of the Pyrenomycet

08-05-2025 20:50

Andreas Jacob

Good evening, due to contstant drought I started

07-05-2025 18:29

Francois Guay Francois Guay

I found this small hyaline ascomycete on moist, de

08-05-2025 02:22

Francois Guay Francois Guay

I found this white, hairy ascomycete on the bark o

08-05-2025 18:32

Ethan Crenson

Hello all, I was looking at leaves of Yucca from

08-05-2025 08:59

Castillo Joseba Castillo Joseba

Me mandan el material de Galicia, (España) , reco

« < 1 2 3 4 5 > »
Nectria
Martin Bemmann, 12-04-2010 23:18
Martin BemmannDear all,

I have here a Nectria, unmature (no asci, no spores), fruiting on a decorticated twig of a decidous tree.
Maybe the white lumps are a hint which taxa can be expected?

Best regards,

Martin
  • message #11087
Martin Bemmann, 12-04-2010 23:18
Martin Bemmann
Re:Nectria
a close view:
  • message #11088
Christian Lechat, 13-04-2010 05:15
Christian Lechat
Re:Nectria
Hi Martin,
your fungus resembles to the genus "Cosmospora" and the white sporodochia are maybe a Fusarium.
Would you have some microscopical illustrations?
Regards,
Christian
Martin Bemmann, 14-04-2010 13:00
Martin Bemmann
Re:Nectria
Hello Christian,

I have kept the stick in a moist environment. Most of the white lumps are dissolved now, but some were still there. Under the microscope it looks like this:
  • message #11102
Martin Bemmann, 14-04-2010 13:00
Martin Bemmann
Re:Nectria
The conidia measure 8,2-10,4x2,8-4,1µm

  • message #11103
Martin Bemmann, 14-04-2010 13:02
Martin Bemmann
Re:Nectria
The ascocarps have developed asci now:

  • message #11104
Martin Bemmann, 14-04-2010 13:04
Martin Bemmann
Re:Nectria
There were no free spores yet. But I measured some of the more mature looking ones: 9,3-10,5 x 5,5-6,2 µm

  • message #11105
Martin Bemmann, 14-04-2010 13:06
Martin Bemmann
Re:Nectria
Finally I tested the asci with IKI. To my opinion the reaction was negative. But one photograph one can think of a small bluish tint at the tip.
Does this help to get further?

Best regards,
Martin
  • message #11106
Christian Lechat, 14-04-2010 14:00
Christian Lechat
Re:Nectria
I Martin,
Anamorph on the substratum looks like an Acremonium, it would be correct for "Cosmospora" but I would like to see some conidiophores and phyalides with conidia to know if it is really an Acremonium. However, nothing proves that this anamorphe is in relation to your Cosmospora
Your fungus is immature, you should wait until it is mature to study it.
Besides, without anamorph in culture it is nearly impossible to know what it is.
Cheers,
Christian
Martin Bemmann, 14-04-2010 23:48
Martin Bemmann
Re:Nectria
Hi Christian,

your estimation was well done, regarding the separation of the anamorph and the unsolvable problem of the teleomorph.
I made a new preparation of these white lumps and it turned out to be something very different than the first one.This time a Fusarium, maybe.
As for the "Cosmospora" I will wait some time to look at it, not expecting to get a name for it, but just having seeing it at a mature stage

Best regards,

Martin

adding some pictures of the "Imperfect of the Day" ;-)

.
  • message #11117
Martin Bemmann, 14-04-2010 23:49
Martin Bemmann
Re:Nectria
next
  • message #11118
Martin Bemmann, 14-04-2010 23:49
Martin Bemmann
Re:Nectria
another
  • message #11119
Martin Bemmann, 14-04-2010 23:50
Martin Bemmann
Re:Nectria
Conidia are this time 51-57x5,6-7,9 µm

  • message #11120
Christian Lechat, 15-04-2010 06:58
Christian Lechat
Re:Nectria
Hi Martin,
I think this anamorph is a Cylindrocarpon / Neonectria . Could you please to send us an image of ascomatal wall in vertical section?
Christian
Martin Bemmann, 15-04-2010 22:26
Martin Bemmann
Re:Nectria
Hi Christian,

what a difficult task to cut a "vertical section" of this tiny fungus! I tried with more then 10 specimen. In vain. Then I experimented with PEG for the first time. And in the second attempt I got this result. Not nice but maybe enough to study:

  • message #11127
Martin Bemmann, 15-04-2010 22:27
Martin Bemmann
Re:Nectria
These are two close-ups:

  • message #11128
Martin Bemmann, 15-04-2010 22:27
Martin Bemmann
Re:Nectria
Best regards,

Martin
  • message #11129
Martin Bemmann, 17-04-2010 00:15
Martin Bemmann
Re:Nectria
Dear Christian,

I read some papers today and saw that Nn. galligena would be an option. It causes a certain canker that I could observe at "my" twig as well. But spore size is still too small (today 7,5-10,7x4,5-5,0 µm).


Best regards,
Martin
  • message #11145
Christian Lechat, 17-04-2010 13:45
Christian Lechat
Re:Nectria
Hi Martin,
here is a plate showing Neonectria ditissima (= N. galligena), it is very different from your collection.
Christian
  • message #11146
Martin Bemmann, 17-04-2010 19:19
Martin Bemmann
Re:Nectria
Thank you Christian!
At least one species excluded! I will wait now until I find mature free spores, before I proceed.

Why is N. ditissima=galligena? Both are valid species in Index Fungorum?

Best regards,

Martin
Christian Lechat, 17-04-2010 21:16
Christian Lechat
Re:Nectria
Neonectria ditissima (Tul. & C. Tul.) Samuels & Rossman, Canadian journal of botany
2006, vol. 84, no9, pp. 1417-1433
= Cylindrocarpon willkommii (Lindau) Wollenw., (1928)
= Fusarium willkommii J. Lindau, in Rabenhorst
= Nectria ditissima var. arctica Wollenw., (1926)
= Nectria ditissima var. major Wollenw., (1926)
= Nectria major (Wollenw.) J. Moravec, (1956)
All the best,
Christian
Martin Bemmann, 17-04-2010 21:29
Martin Bemmann
Re:Nectria
Ok, thanks again for directing me to the Castlebury/Rossman/Hyten paper.
I will study it.

Cheers,
Martin