Nuclear microprobe studies of elemental distribution in mycorrhizal and non-mycorrhizal roots of Ni-hyperaccumulator Berkheya coddii

Micro-particle-induced x-ray emission (PIXE) was used to assess the influence of arbuscular mycorrhiza on the elemental concentration and distribution in roots of Berkheya coddii and to evaluate the role of fungal hyphae in elemental uptake by this plant. Analysis revealed a significant influence of mycorrhiza on the concentration and distribution of elements in roots of B. coddii. Mycorrhizal roots had significantly higher concentration of P, Ca, Zn and Cu than the non-mycorrhizal ones. The mycorrhizal fungi also affected the distribution of elements (P, K, Cl, Zn and Ni) within the roots. The external fungal hyphae showed a high binding capacity of metals (Cu, Zn, and Ni). Matrix corrections done on the basis of simultaneous use of proton backscattering technique were essential due to the highly variable thickness of analyzed specimens. Copyright (C) 2008 John Wiley & Sons, Ltd.