Endophytic fungi in needles of healthy-looking and diseased Norway spruce (Picea abies [L.] Karsten). Endophytic fungi were isolated from surface-sterilized, 5 to 6 year old needles of healthy-looking and diseased trees. Two fungal species could be isolated frequently: Lophodermium piceae and Tiarosporella parca. At any site neither L. piceae nor T. parca could be isolated more frequently from needles of diseased trees. The possible types of relationship between these two fungi and Norway spruce are discussed.

Endophytische Pilze in Nadeln von gesunden und geschädigten Fichten (Picea abies [L.] Karsten)

Diversity of Norway spruce needle endophytes in various mixed and pure Norway spruce stands

Lophodermium piceae (probably conspecific with L. nanakii ) was found to be the predominating endophyte in the laminae of I- to 4-year old needles of Picea abies in southern Sweden. The fungus did not appear to be pathogenic and was more common in young, healthy stands than in stressed diseased ones.

Occurrence and pathogenicity of Lophodermium piceae appearing as an endophyte in needles of Picea abies

ZusammenfassungAus Süddeutschland wird eine weit verbreitete Pilzschütte beschrieben, die vornehmlich ältere Fichtenbestände befällt und weitgehend der vonHartig (1889),Nobbe (1893) undNeger (1924) beschriebenen Nadelröte entspricht. Sie grassiert mindestens seit Herbst 1981 und dürfte weitgehend für die Zunahme der Fläche erkrankter Fichtenbestände von 1982 auf 1983 verantwortlich sein. Die beteiligten Erreger sindLophodermium piceae, L. macrosporum, Rhizosphaera kalkhoffii u. a. Die Erkrankung tritt weitgehend unabhängig von Muttergestein, Regionalklima, Bodenform, Standortseinheit, Ernährungszustand und Immissionsbelastung auf. Daher halten wir die Erkrankung für überwiegend witterungsgesteuert. Eine Arbeitshypothese über Ursachen und Ablauf wird zur Diskussion gestellt.SummaryThe paper reports on a widespread needle cast occuring mainly in older Norway spruce stands in southern Germany which corresponds to the “Nadelröte” disease as described byHartig (1889),Nobbe (1893) andNeger (1924).Severe needle losses have been observed at least since autumn 1981, and this disease seems to be responsible for the increase of the area of damaged spruce forests from 1982 to 1983. Premature shedding of older spruce needles is mainly caused by the needle parasitesLophodermium piceae, L. macrosporum, andRhizosphaera kalkhoffii a. o. There are no correlations between the occurrence and intensity of the needle cast on the one hand and parent rock, the regional climatic conditions, soil type, site unit, nutritional status of the stands, or the degree of pollution on the other hand. There is evidence for this disease being predominantly determined by weather factors. A working hypothesis about the causes and the development of this disease is put forward.

Über die Nadelröte-Erkrankung der Fichte (Picea abies Karst.) in Süddeutschland@@@On the “Nadelröte” disease of Norway spruce (Picea abies Karst.) in southern Germany

Antiserum specific for Lophodermium piceae hyphae was obtained by absorbing a rabbit L. piceae antiserum with hyphal material of different fungal isolates. The specificity of this absorbed antiserum was tested with hyphae of endophytic fungi isolated from green, asymptomatic needles of Norway spruce (Picea abies Karst.) using the on-section immunogold labeling technique. With this specific, absorbed antiserum, a homogenous labeling was obtained with cultured hyphae of L. piceae, whereas all other spruce needle endophytes examined remained practically unlabeled. Insignificant cross-reactivity was also observed with needle tissues. The absorbed antiserum was then applied for the immunoelectron microscopical identification of L. piceae hyphae in situ in infected tissues of green, asymptomatic Norway spruce needles. The function of papillalike structures observed in infected needle mesophyll as well as the role of the hyphal sheath surrounding endophytic L. piceae hyphae are discussed in connection with the i...

Identification of endophytic hyphae of Lophodermium piceae in tissues of green, symptomless Norway spruce needles by immunoelectron microscopy

Experimental proof of needle inhabiting fungi in conifers. I. Spruce (Picea abies). Various methods are described, which can be used to establish the presence of fungi in needles of conifers and to classify them. Culture characteristics of Lophodermium piceae, L. filiforme, Rhizosphaera kalkhoffii, Thysanophora penicillioides and Tiarosporella parca arc given.

K. Rack

Papers

Experimenteller Nachweis nadelbewohnender Pilze bei Koniferen. I. Fichte (Picea abies)