Record ID No. |
1325 |
Author(s) |
Gibson B. R., Mitchell D.T. , 2005 |
Affiliation |
Department of Botany, University College Dublin, Dublin 4, Irish Republic. |
Title |
Influence of pH on copper and zinc sensitivity of ericoid mycobionts in vitro |
Source. Vol.(no):Page |
Mycorrhiza.15(3): 231-234p. |
Categories |
Ericoid Mycorrhiza |
Subjects |
Soil plant relations |
Sub-subjects |
Soil reaction |
Host |
ErM |
Organism |
Hymenoscyphus ericae |
Country |
Ireland, Europe |
Abstracts |
The effect of pH on growth, metal uptake and toxicity in four isolates of ericoid mycobionts (two Hymenoscyphus ericae from unpolluted heathland sites and two H. ericae-type mycobionts from metal-contaminated mine spoil) was assessed in vitro. These isolates were incubated in liquid medium (10% Rorison's medium, glucose at 10 g l-1) containing either 0.25 mM Cu or 2.0 mM Zn and adjusted to pH 2, 3, 4, 5 or 6. After 30 days incubation, dry mass and mycelial metal content were determined and growth was expressed as tolerance index, i.e. dry mass in the presence of metal as a percentage of dry mass in the absence of metal. Initial medium pH had a significant effect on both tolerance index and metal accumulation. Tolerance indices were highest at pH 2, with several isolates showing a stimulation of growth (i.e. tolerance index >100%) at this pH. Tolerance index decreased at higher initial pH values and growth of two mycobionts was completely inhibited (tolerance index=0) in the Cu-supplemented media at pH 6. Reduction in tolerance index coincided with an increase in mycelial accumulation of Cu and Zn. Practical and environmental implications of these results are discussed.. |