23-10-2025 20:59
Patrice TANCHAUDBonsoir, est-ce que quelqu'un posséderait un com
20-10-2025 09:36
Nicolas VAN VOOREN
Hello.I'm searching for the following article:Bene
21-10-2025 23:13
F. JAVIER BALDA JAUREGUIHello to everyone.Did you think it could, be a pyx
22-10-2025 14:45
Lukas VerboomDear all,I collected this in the Netherlands, on t
22-10-2025 11:13
Jean-Luc RangerBonjour, Petites boules plus ou moins sphériqu
21-10-2025 21:25
Philippe PELLICIERBonjour,J'ai récolté en septembre sur une litiè
17-10-2025 18:45
Riet van Oosten
Hello, Found by Laurens van der Linde, Oct. 2025.
Seimatosporium cf. lichenicola on Rosa canina ?
Thorben Hülsewig,
04-05-2018 22:52
today i found this black spots on Rosa canina and i think it may be the genus Seimatosporium. The conidia are only 3-septate and appendages are up to 10 Micrometer long.
Could this be Seimatosporium lichenicola ?
best regards,
Thorben
Joey JTan,
05-05-2018 04:56
Re : Seimatosporium cf. lichenicola on Rosa canina ?
I think of S. lichenicola as having more pigmented, thicker-walled, clavate conidia with wider and darker septa, but your conidia might be young. Seimatosporium lichenicola also often lacks appendages, but your dimensions are similar to those reported by others for this species. I looked at Shoemaker (1964) and didn't find a satisfactory match, e.g. similar to Seimatosporium discosioides except for the appendage length and possibly habit (I'm not sure if S. discosioides is reported from stems). Doesn't match S. rosae either.
Shoemaker, R.A., 1964. Seimatosporium (= Cryptostictis) parasites of Rosa, Vitis, and Cornus. Canadian Journal of Botany, 42(4), pp.411-421.
Chris Yeates,
05-05-2018 17:11
Re : Seimatosporium cf. lichenicola on Rosa canina ?
I too cannot make a satisfactory match; though it surely isn't S. lichenicola, which in my experience usually has collapsed walls.