Assessment of the contributions of glycolysis and the pentose phosphate pathway to glucose respiration in ectomycorrhizas and non - mycorrhizal roots of spruce ( Picea abies L . Karsten )

more photosynthates than non-mycorrhizal ones, allocate a greater fraction of the assimilated carbon to the root systems and lose a greater fraction of the assimilated carbon to respiratory C0 2 than do non-mycorrhizal plants (for a review, see Martin et al., 1987). The establishment of a carbon sink by the ectomycorrhizal hyphae may be attained by: 1 ) rapid carbohydrate degradation for respiration and for energy and reducing power production and 2) conversion of plant carbohydrates into fungal biomass. The high respiration rate of fungal tissues has been pointed out by several authors (France and Reid, 1983). Most studies of mycorrhizal respiration deal with mitochondrial respiration. Much less is known about the oxidative