Affiliations: Department of Environmental Engineering, Zhejiang
University, Hangzhou 310029, China | Institute of High Energy Physics, Chinese Academy of
Sciences, Beijing 100039, China
Abstract: Phytolacca acinosa Roxb. (P. acinosa) is a recently discovered
manganese hyperaccumulator plant from southern China. It is a good candidate
for phytoremediation of manganese(Mn) polluted soil for its high biomass and
fast growth. Knowledge of the tissue localization and identification of heavy
metals can provide essential information on metal toxicity and bioaccumulation
mechanisms. Synchrotron radiation X-ray fluorescence spectroscopy (SRXRF)
microprobe was used in this study to investigate the cellular distributions of
Mn and other elements in root, stem, leaf, petiole and midrib ofP. acinosa. The
highest Mn content was found in the vascular tissues of root, stem, petiole and
midrib. Cortex in root played a key role in Mn absorption and Mn was limited in
the vascular bundle during the process of transportation in stem. Moreover, Mn
content in leaf epidermis was higher than that in mesophyll, which suggested
that the sequestration of Mn in leaf epidermis might be one of the
detoxification mechanisms of P. acinosa. The significance of other elemental
(such as P, S, K, Ca, Fe, Zn and Cu) distribution patterns and the correlation
with Mn were also discussed.
Keywords: hyperaccumulator, Phytolacca acinosa Roxb., manganese, element distribution, SRXRF
