Growth and interspecific interactions of the rare oak polypore Piptoporus quercinus.

Growth and interactions of Piptoporus quercinus were studied in artificial culture to give insights into the ecological characteristics of a species which is both rare and widespread. P. quercinus grew slowly under all conditions, the maximum ranging between 1.9 and 3.15 mm d(-1), depending on isolate, at 25 degrees C pH 3.75. Upper limits for growth were 25-30 degrees or above 30 degrees depending on isolate, and pH 6.6. Lower limits for growth were 5-10 degrees, between -1.75 and -2.5 MPa; there was still growth at pH 1.81. Preincubating plates at 5 for 77 d and then incubating at 20 degrees resulted in a significantly greater extension rate (2.89 mm d(-1)) than when incubated continuously at 20 degrees (1.70 mm d(-1)) for one isolate though not for another isolate. P. quercinus survived exposure to low temperature (-18 degrees for 7 d), showing renewed growth, albeit limited, after a lag of 37 d. It was a poor combatant, being unable to replace any of the eight fungi (with a range of ecological roles) against which it was paired, and being replaced or partially replaced by most, on 2% MA at pH 5.49, at pH 3.75 and at -1.25 MPa. It did, however, inhibit extension rate of some other heart rot fungi. Results are discussed in an ecological context.

Interspecific interactions between the rare tooth fungi Creolophus cirrhatus, Hericium erinaceus and H. coralloides and other wood decay species in agar and wood.

Creolophus cirrhatus, Hericium erinaceus and H. coralloides were paired against over 20 other wood decay fungi from beech (Fagus sylvatica) covering a range of ecological strategies, on 2% malt agar (MA), 0.5% MA, 0.5% MA adjusted to -1.25 MPa by addition of KCl, 0.5% MA adjusted to pH 4 with KOH/H3PO4 and 0.5% MA under 5% O2/30% CO2 all at 20 degrees C. Creolophus cirrhatus and H. coralloides were also paired against 17 other species in wood, incubated at 20 degrees for 36-38 wk. They were average to good combatants, deadlocking with or replacing over half of the antagonists, H. erinaceus being slightly more combative than the other two species. Outcomes in wood were representative of those in agar. Abiotic conditions altered the outcomes slightly, reduced water potential favouring C. cirrhatus and H. erinaceus. Overall extension rate of C. cirrhatus and H. erinaceus often increased in the presence of antagonists. There was prolific production of fruit bodies in controls and interactions, though notably not under altered gaseous regime. Results are discussed in an ecological context.