Septoria juliae sp. nov. – a new Septoria species on Nerium oleander
Septoria juliae sp. nov. – eine neue Septoria-Art an Nerium oleander
Journal für Kulturpflanzen, 63 (12). S. 430–431, 2011, ISSN 1867-0911, DOI: 10.5073/JfK.2011.12.04, Verlag Eugen Ulmer KG, Stuttgart
Septoria juliae sp. nov., a new species collected on Nerium oleander L., differs from other species of Septoria on this host in length, width and number of septa of the conidia.
Key words: Septoria juliae sp. nov., Nerium oleander, symptoms, systematics, new species
Septoria juliae sp. nov., eine neue Art an Nerium oleander L., unterscheidet sich von anderen Arten der Gattung Septoria auf diesem Wirt in Länge, Breite und Anzahl der Septen der Konidien.
Stichwörter: Septoria juliae sp. nov., Nerium oleander, Symptome, Systematik, neue Art
On Oleander (Nerium oleander) we know four different species of Septoria, namely S. oleandrina Sacc., S. roll-hansenii Morelet, S. neriicola Pass., and S. oleandriicola (E. Hüsein and F. Selcuk). Except S. neriicola all others cause white-brownish leafspots with pycnidia on them. Typically the leafspots are surrounded by a thin dark brown margin. S. neriicola only develops pycnidia on the reverse side of the leaves.
On leaves of Nerium oleander originating from a nursery in Eferding (Upper Austria) a Septoria species was identified which differs in the number, length and width of septa to the well known species on Nerium oleander.
For identification and comparison the following material, borrowed from herbarium collections of the Natural History Museum in Vienna, was examined: the holotype of Septoria oleandrina Sacc. (Rabenhorst, Fungi europaei, No. 2158), S. oleandrina Sacc. (F. Petrak, Pilzherbarium, Herb. Mus. Hist. Natur. Vindob. No. 13643), S. oleandrina Sacc. (Briosi et Cavara – I Funghi parassiti delle piante cultivate od Utili, Nr. 371).
The pycnidia and conidia were measured by the electronic image analysis system “Zeiss Axiovision Rel. 4.8”.
The main difference between Septoria neriicola (Saccardo, 1884) opposed to the other species and the new one is the lack of septa in the conidia. Septoria juliae sp. nov. differs from S. roll-hansenii (see below) and S. oleandriicola (Saccardo, 1876) in the number of septa in the conidia and particularly in the length and width of the conidia. In my opinion it looks as if S. roll-hansenii and S. oleandriicola are identical, because of the length, width and number of septa of the conidia. The original description of S. roll-hansenii is apparently not detectable because of dubious bibliographic specifications (see both Morelet, 1973a, b), but that of Septogloeum nerii is available. This species is a nomen nudum and Morelet (1973a, b) renamed it Septoria roll-hansenii. Septogloeum nerii (Bernaux, 1949) has conidia with 0–4 septa which measure 25–39 × 3–4 µm and therefore S. roll-hansenii seems to be identical to S. oleandriicola (Hüseyin and Selcuk, 2002). The material of S. oleandrina in the collection of Briosi et Cavara (see above) seems not to be S. oleandrina, because the conidia have 1–3 septa and measure 11.53–25.95 × 1.03–2.29 µm. Petrak’s material is identical to the holotype.
The diameter of the pycnidia of the new species is 35.01–203.26 µm. The conidia are 26.36–54.61 µm long and 2.53–5.67 µm wide and have 1–7 septa (Table 1).
Table 1. Septoria species on Nerium oleander
Species | Length of conidia | Width of conidia | Number of cells |
Septoria oleandrina Sacc. Typus** | 9.39–19.11 | 0.86–1.63 | 1–2 |
Septoria roll-hansenii Morelet (= Septogloeum nerii Berneaux)* | 25–39 | 3–4 | 1–5 |
Septoria neriicola Pass.* | – | – | 1 |
Septoria oleandriicola E. Hüsein & F. Selcuk* | (12.5)22.5–37.5(40) | 2.5–3(4.5) | 2–4(5) |
Septoria juliae sp. nov.** | 26.36–54.61 | 2.53–5.67 | (2)3–7(8) |
* according to original descriptions | |||
Maculae hypophylla et epiphylla foliis breve immersis, albido-brunneae, non angularis, atrobrunneo margine distincte. Conidiomata (pycnidiae) in maculis, plerumque epiphylla. Primo immersa in textura foliae, tandem erumpentes, globosa, 35,01–203,26 µm diam., (magnitudo media 121,52 µm). Conidia hyalina, filiforma, recta-curvata, 1-6-septata, plerumque 2-7-septata, 26,36–54,61 µm longa et 2,53–5,67 µm crassa. Hab. in foliis vivis Nerii oleandris.
Type: Austria, Eferding (Brandstätter Straße, Gärtnerei Sandner)/Oberösterreich (Upper Austria). On living leaves of Nerium oleander L. 26 08 1998, G. Bedlan (holotype, hb W).
The type specimen has been deposited at the Department of Botany, Natural History Museum, Vienna.
I would like to thank Dr. A. Igersheim (Natural History Museum, Vienna) for critically discussion and providing helpful information on systematics and Dr. Th. L. Cech (Federal Forest Office, Vienna) for Latin translations.
Bernaux, P., 1949: Quelques champignons parasites nouveaux de France. Revue de Pathologe Végetale et d'Entom. Agric. de France 28, 147.
Hüseyin, E., F. Selcuk, 2002: Septoria oleandriicola sp. nov., a new species from Nerium oleander in Turkey. Mycological Progress 1(2), 143-145.
Morelet, M., 1973a: Ann. Soc. Sci. Nat. Arch. Toulon et du Var 204: 8.
Morelet, M., 1973b: Bull. Soc. Sci. Nat. Archéol. Toulon & Var 204: 8.
Saccardo, P.A., 1876: Nuovo Giorn. Bot. Ital. 8, 205.
Saccardo, P.A., 1884: Sylloge fungorum omnium hucusque cognitorum. Vol. III, 497.
Wittmann, W., 1970: Ein neues Rezept zur Herstellung mykologischer Präparate. PflSchber. 41, (5/6/7), 91-94.
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