Salt Uptake and Respiration of Excised Beech Mycorrhizas

Abstract

SUMMARYWhen excised beech mycorrhizas aged in aerated water absorb ammonium from NH4CI solutions in the presence of low concentrations of ^T-labelled KH2PO4, the incorporation of^P in the tissues during a 2-min period was greater than when ammonium was not supplied. At the same time, the respiratory rate was also greatly increased. The destination of the phosphate incorporated was similar whether ammonium was present or not. The results are consistent with the view that the respiratory rate of aged beech mycorrhizas is limited by the rate of phosphate turnover and the availability of phosphate acceptors, and that the absorption of ammonium increases this turnover.

Applications of Continuous and Steady-State Methods to Root Biology

“…Harley et al (1956) were able to estimate sheath respiration by excising the sheath from the core (root tissue plus Hartig net) of ECM beech and separately measuring the sheath and core respiration by manometry. Estimates of fungal respiration have been obtained in several ECM studies; however, such respiration is often very difficult to separate from root respiration.…”