Fwd. Rost et al., ESTIMATION OF VACUOLAR PH IN ACTIVELY GROWING HYPHAE OF THE FUNGUS PISOLITHUS-TINCTORIUS, Mycological research, 99, 1995, pp. 549-553
The pH of vacuoles in tip cells of growing hyphae of a mycorrhizal fun
gus, Pisolithus tinctorius, was estimated by dual-wavelength microspec
trofluorometry of 6-carboxyfluorescein. The vacuoles were found to hav
e a modal pH of 7.0-7.5 and a pH range of 4.3-7.5. Vacuoles in penulti
mate cells tended to be more acid, with a modal group pH 5.5-6.0, alth
ough the range was similar at pH 4.8-7.2. The findings are discussed i
n relation to endocytosis and ageing of vacuoles in P. tinctorius.