Arbuscular Mycorrhizal Fungi and Arsenate Uptake by Brachiaria Grass (Brachiaria decumbens)

Abstract

ABSTRACT Using a compartmentalized treatment technique, the role of arbuscular mycorrhizal fungi (AMF; Acaulospora scrobiculata) on arsenic (As) uptake and translocation in Brachiaria decumbens. Treatments consisted of a factorial arrangement of three As doses (0, 50, and 100 mg kg⁻¹) and the presence/absence of AMF inoculates. In the absence of AMF, B. decumbens did not show As accumulation, indicating the probable presence of tolerance mechanism via As exclusion by the roots. B. decumbens plants showed high AMF colonization levels, especially in the arsenic treatments, with AMF improving shoot and root growth independent of As concentrations. Arsenic accumulation occurred only with AMF inoculation. Phosphorous uptake was reduced in B. decumbens roots in the presence of arsenic with and without inoculation of AMF. Results suggest that B. decumbens can be used in phytoremediation procedures when inoculated with A. scrobiculata, although pasture formation should be strictly avoided in contaminated sites.

KEYWORDS:

• Acaulospora
• arsenic
• contamination
• phytoremediation

ACKNOWLEDGMENTS

The authors are grateful to Dr. Fabio Vieira (UFMG) for providing and improving the figures.

FUNDING

The authors are grateful to CAPES for the study grant awarded to the first author.