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24-01-2025 18:09

Nogueira Héctor

19/01/2025 Villameca (León) España  Buenas En

26-01-2025 00:18

Robin Isaksson Robin Isaksson

Hi! Anyone know this one? Spores 14-18 x 4-4

23-01-2025 17:09

Karen Poulsen

Hi all Could this be P. merdae? Found on differe

22-01-2025 15:56

Vasileios Kaounas Vasileios Kaounas

Found in sandy soil, in forest with Pinus halepens

24-01-2025 19:39

Margot en Geert Vullings

We found these orange dics on horse dung.We think

24-01-2025 18:39

Jean-Luc Ranger

Bonjour, j'ai ce petit ascome d'1,5 mm de diamètr

23-01-2025 15:46

Malcolm  Greaves Malcolm Greaves

Could I have peoples opinion on this Geoglossum.Wi

23-01-2025 23:32

Yanick BOULANGER

BonsoirSur tige d'herbacé (non reconnue)Yanick

22-01-2025 18:14

Jean-Luc Ranger

Bonjour, J'ai trouvé sur une Helvella un feutrage

19-01-2025 18:36

William Slosse William Slosse

Good evening everyone, on 16-01-2025 I found this

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Fusarium/Gibberella?
Lepista Zacarias, 01-02-2017 11:58
This fungus was found growing on a non-identified shrub (a photos of its leaves is attached) at the border of a forest, where many other shrubs live, like Arbutus unedo, Pittosporum undulatum, Quercus coccifera, just to mention some.
At first I had no idea about its classification, but it has very distinguish features, namely:

- A blue pigment on all the tissues of the perithecia,
- some big (sub-)globose cells at the bases of the asci (up to 30 um).
- some big conidia, comma shaped, septate, some seeming to have some internal oil drops.


Searching the forum for "bleu pyréno" I found the topic by Luc Bailly "Pyréno bleu foncé sur Arnica montana" (#17317), where some connection was made to the genus Gibberella. I got the "Gibberella" key by Samuels et al., where the identification of species rely on the anamorph, a Fusarium sp..
The question is that such key only contains species with septate ascospores (one or more septa) and I was not able to see any septation on the spores, though the photos are not clear do to hyalinity and the existence of many drops inside the asci and arround the spores, which perturb their observation. Thus, I only give their approximate dimensions: 12 - 17.5 x 3.3 - 5.6 um.
Can anyone help?


I will upload some photos in different messages to this topic, starting for those of the specimens.


Thanks in advance,
zaca

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Lepista Zacarias, 01-02-2017 12:02
Re : Fusarium/Gibberella? - SECTIONS
Perithecial sections ...
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Lepista Zacarias, 01-02-2017 12:09
Re : Fusarium/Gibberella? - Asci and spores
Asci and spores ...
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Lepista Zacarias, 01-02-2017 12:11
Re : Fusarium/Gibberella? - CONIDIA
Conidia ...
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Martin Bemmann, 01-02-2017 12:18
Martin Bemmann
Re : Fusarium/Gibberella?
Leaves of host look like Coronilla minima:
http://www.floravascular.com/index.php?spp=Coronilla%20minima

regards
Martin
Lepista Zacarias, 01-02-2017 12:37
Re : Fusarium/Gibberella?
Thanks, Martin,
It seem very likely. So, maybe next month I can see the flower.
Regards,
zaca
Martin Bemmann, 01-02-2017 13:28
Martin Bemmann
Re : Fusarium/Gibberella?
One of the synonyms of Gibberella zeae is Gibberella saubinetii var. coronillae Sacc., Michelia 1(no. 5): 513 (1879) (attached)
But spores should be 3-septate indeed. Unmature?

Regards
Martin
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Lepista Zacarias, 01-02-2017 13:40
Re : Fusarium/Gibberella?
Thanks again, Martin.
I'm new to these genera. I have to look again for the spores and conidia. Any suggetsion for the stain, in order to better see the possible septation?
Regards,
zaca
Martin Bemmann, 01-02-2017 13:52
Martin Bemmann
Re : Fusarium/Gibberella?
best is to have released mature spores. You could try brilliant cresyl blue.
Martin
Lepista Zacarias, 01-02-2017 15:59
Re : Fusarium/Gibberella?
I don't expect an overdose of mature spores. I will try the blues I have cresyl (alcoholic solution) and lactic.
Thanks, Martin!
Regards,
zaca
Lepista Zacarias, 01-02-2017 22:19
Re : Fusarium/Gibberella?
I tried to stain the spores and, after seeing many non-septated spores, as before, at the end I succeded to observe at a part of the slide some consistently 1-sepate, except for one ascus where coexist 1- 2- and 3-septate spores. I have obtained some better photos for conidia (I updated the corresponding photos) and add some new of the septate ascospores.
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Martin Bemmann, 02-02-2017 10:49
Martin Bemmann
Re : Fusarium/Gibberella?
Hi Zaca,

congrats for the septa! I would file this now at least as Giberella zeae cf. since you found only few with 3 septa, but variation is known:
https://www.jstor.org/stable/3807718?seq=1#page_scan_tab_contents

regards
Martin
Lepista Zacarias, 02-02-2017 14:00
Re : Fusarium/Gibberella?
ThanK you, Martin, once more.
You seem to have an inexhaustible source of material related with Fusarium/Giberella. I could not read the whole paper at the link you provided (no access), but the abstract is clear about the variation of the septation of the ascospores in G. zeae. However, I have the reverse of the situation therein, a big amount of one-celled, a part with 2-cells and a very small part with 3 and 4 cells (these occuring in only one ascus). On the other hand, as far as I understand, the conidia seem to fit the anamorph Fusarium species with telemorph G. zeae, Fusarium graminearum (compare with the paper by DlMlTR ATANASOFF in Journal of Agricultural Research Vol. 20 (no. 1), 1920). Thus, as you proposed, by now I will leave it as G. cf. zeae.
Best regards,
zaca
Lepista Zacarias, 07-02-2017 22:19
Re : Fusarium/Gibberella?
Dear all,
Just to update the data from microscopy, since this time and after several failed attempts I succeeded to observe many 3-septate spores, one more point in favour of Gibberella zeae. My acknowledgements to Martim Bemmann, who knew from the beginning that sooner or later I will arrive to this point.
Best regards,
zaca
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Martin Bemmann, 07-02-2017 23:26
Martin Bemmann
Re : Fusarium/Gibberella?
Dear Zaca,
I did know nothing. I just followed a narrow path starting by identifying the host and then using my digital library. I am far off to be an expert on Giberella....
I just had fun to solve this riddle, as you had ? Thank you for sharing this!
Best regards
Martin