Mn accumulation and tolerance in Celosia argentea Linn.: A new Mn-hyperaccumulating plant species

Identifying a hyperaccumulator is an important groundwork for the phytoextraction of heavy metal-contaminated soil. Celosia argentea Linn., which grew on a Mn tailing wasteland, was found to hyperaccumulate Mn (14 362 mg kg−1 in leaf dry matter) in this study. To investigate Mn tolerance and accumulation in C. argentea, a hydroponic culture experiment was conducted in a greenhouse. Results showed that the biomass and the relative growth rate of C. argentea were insignificantly different (p > 0.05) at the Mn supply level ranging from 2.5 mg L−1 (control) to 400 mg L−1. Manganese concentrations in leaves, stems, and roots reached maxima of 20 228, 8872, and 2823 mg kg−1 at 600 mg Mn L−1, respectively. The relative rate of Mn accumulation increased by 91.2% at 400 mg Mn L−1. Over 95% of the total Mn taken up by C. argentea was translocated to shoots. Thus, C. argentea exhibits the basic characteristics of a Mn-hyperaccumulator. This species has great potential to remediate Mn-contaminated soil cheaply and can also aid the studies of Mn uptake, translocation, speciation, distribution and detoxification in plants.