Effects of liming on ectomycorrhizal fungi infecting Pinus sylvestris L.

Abstract

summary Growth rates of ectomycorrhizal fungi were measured in pure culture at pH 3–8 on MMN‐agar and sterilized peat, with and without nutrients added. Mycorrhizas were synthesized with Pinus sylvestris L. seedlings and the growth rate of the external mycelium was measured in peat at pH 3.8 and 7.3. The fungi were three isolates of Piloderma croceum Erikss. & Hjorts., two isolates of an unidentified (pink) mycorrhizal type and one isolate of another unidentified (white long) mycorrhizal type, all isolated from P. sylvestris roots. All three fungi showed much higher (2–5 times) growth rates when grown as symbionts than when grown in pure culture. The P. croceum isolates also grew as symbionts at pH 7.3, where no growth occurred in pure culture. These findings emphasize the danger of generalizing from data obtained in pure culture studies to explain what may happen when fungi grow in symbiosis with host plants. Generally, growth rates in pure culture were higher and the pH tolerance levels were wider on agar than on peat. The exceptions were one P. croceum isolate, which had the fastest pure culture growth rate on peat with MMN, and the pink isolates, which grew at higher pH on peat than on agar. There were no significant differences between growth on peat with and without MMN.

Cross talks at the morphogenetic, physiological and gene regulation levels between the mycobiont Piloderma croceum and oak microcuttings (Quercus robur) during formation of ectomycorrhizas

“…P. fallax is characterized by a low growing mycelium highly sensitive to temperature (Erland and Finlay, 1992). Mycelium extension is increased when the fungus is connected with host plants (Erland et al, 1990), and Dahlberg and Stenströ m (1991) demonstrated connections with mature host plants to be important for efficient colonization of young seedlings.…”

Genetic variations of ectomycorrhizal fungi: extramatrical phase of Pisolithus sp.

“…Other facvide further information on fungal-root physiology interactors such as the absence of associated microflora, nutrient tions during water stress. An understanding of the mechanisms levels, temperature, soil pH, fungal growth factors, and plant determining intraspecific variability in mycelial strand forroot exudates also affect development of the extramatrical mation, extension of the extramatrical phase, and physiologphase (Bethelenfalvay et al 1988;Coutts and Nicoll 1990; ical response to adverse stress could advance our kncwledge Erland et al 1990;Garbaye and Bowen 1987;McAffee and and enable us to apply biotechnology to reforestation. Fortin 1988; Slankis 1974).…”

The ectomycorrhizal community of conifer stands on peat soils 12 years after fertilization with wood ash

“…In general, differences in ECM fungal community composition have been observed after lime application (Andersson and Söderström 1995;Erland and Taylor 2002;Kjøller and Clemmensen 2009). ECM fungal mycelium was shown to grow slower in limed peat substrate with increased pH than in unlimed peat (Erland et al 1990). Wood ash and lime are rather similar in their buffering capacity, but wood ash contains larger amounts of K, Mg, Mn, Na and P as well as toxic heavy metals (Augusto et al 2008).…”