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Valsa on Prunus spinosa branches
Enrique Rubio,
07-04-2012 19:31
Hello my friends of the forum:I'd like to know your opinion about this fungus that forms erumpent stromata on Prunus spinosa branches lying on the ground.
Stromatic disc is witish/grayish and the stromata have a conspicuous ventral black line. Spores are hyaline and very heterometrical. Many asci with 8 ascospores.
We think this is a Valsa species but we have not seen his Cytospora anamorphic state.
Maybe Valsa ambiens?
Many thanks again
Enrique
Björn Wergen,
07-04-2012 21:10
Re : Valsa on Prunus spinosa branches
Hi Enrique,
I also think it should be V. ambiens. See Spielman 1985.
regards,
björn
I also think it should be V. ambiens. See Spielman 1985.
regards,
björn
Enrique Rubio,
08-04-2012 11:30
Re : Valsa on Prunus spinosa branches
Many thanks, Björn
Enrique
Enrique
Vera Hayova,
08-04-2012 21:09
Re : Valsa on Prunus spinosa branches
Hello,
It can't be Valsa ambiens since there is the black delimitation line. I would suggest it's Leucostoma cinctum.
To make sure, try to do transversal cross-sections of several ascostromata. You can find remnants of the anamorph (usually different in colour) in the upper part of some of them, right in the middle. If it is so, then it is surely L. cinctum. In fact, it already seems so on your pic 1, on the transverse section that is below on the right. This is a distinguishing character of the species, plus your dimensions fit it well.
Hope this is helpful.
Vera
It can't be Valsa ambiens since there is the black delimitation line. I would suggest it's Leucostoma cinctum.
To make sure, try to do transversal cross-sections of several ascostromata. You can find remnants of the anamorph (usually different in colour) in the upper part of some of them, right in the middle. If it is so, then it is surely L. cinctum. In fact, it already seems so on your pic 1, on the transverse section that is below on the right. This is a distinguishing character of the species, plus your dimensions fit it well.
Hope this is helpful.
Vera
Enrique Rubio,
09-04-2012 18:40
Re : Valsa on Prunus spinosa branches
Hi Vera
What color has the anamorph? and what are the conidia?. Have you literature or images about this species?
Many thanks for ypur kindly help
What color has the anamorph? and what are the conidia?. Have you literature or images about this species?
Many thanks for ypur kindly help
Vera Hayova,
10-04-2012 14:17
Re : Valsa on Prunus spinosa branches
Hi Enrique,
Information on this species is limited and very scattered as on many of Valsaceae.
L. cinctum is known to have both anamorph and teleomorph in one stroma. Sometimes, it is easy to notice, even without a cross section, like on photo 1 where pycnidial ostiole is clearly seen surrounded by ascomatal ostioles. In this case, conidioma remains inside there, although appearing rather unusual (photo 2) but conidia still can be found there; they look like tiny ascospores. At a later stage, when perithecia have mature asci, normally one can see only remnants of the anamorph as a greyish mass.
Vera
PS. Pictures taken also on Prunus spinosa.
Information on this species is limited and very scattered as on many of Valsaceae.
L. cinctum is known to have both anamorph and teleomorph in one stroma. Sometimes, it is easy to notice, even without a cross section, like on photo 1 where pycnidial ostiole is clearly seen surrounded by ascomatal ostioles. In this case, conidioma remains inside there, although appearing rather unusual (photo 2) but conidia still can be found there; they look like tiny ascospores. At a later stage, when perithecia have mature asci, normally one can see only remnants of the anamorph as a greyish mass.
Vera
PS. Pictures taken also on Prunus spinosa.
Enrique Rubio,
10-04-2012 14:47
Re : Valsa on Prunus spinosa branches
Thank you Vera
Do you know what are morphologically the conidia and its measures?
Do you know what are morphologically the conidia and its measures?
Vera Hayova,
10-04-2012 15:25
Re : Valsa on Prunus spinosa branches
Conidia are similar in shape to ascospores but much smaller - allantoid, hyaline, about 6-7 x 1.5 mkm.
Enrique Rubio,
10-04-2012 18:01
Re : Valsa on Prunus spinosa branches
Dear Vera:
Unfortunately I could not have found anamorphe remains.
Many thanks for you help
Enrique
Unfortunately I could not have found anamorphe remains.
Many thanks for you help
Enrique
Vera Hayova,
10-04-2012 18:36
Re : Valsa on Prunus spinosa branches
Hi Enrique,
Anyway I think it's L. cinctum, due to asci/ascospore dimensions. You probably have all mature ascostromata and it's too late to see anamorph.
Best wishes,
Vera
Anyway I think it's L. cinctum, due to asci/ascospore dimensions. You probably have all mature ascostromata and it's too late to see anamorph.
Best wishes,
Vera
Enrique Rubio,
10-04-2012 18:48
Re : Valsa on Prunus spinosa branches
OK., Vera.
Next week end i'll try to collect more material and I will looked for the anamorphic state on more branches.
Many thanks!
Enrique
Next week end i'll try to collect more material and I will looked for the anamorphic state on more branches.
Many thanks!
Enrique
Vera Hayova,
10-04-2012 18:55
Re : Valsa on Prunus spinosa branches
OK, good luck. Let me know if you find it. I believe this feature of the species should be everywhere the same.