Manganese tolerance and accumulation characteristics of a woody accumulator Camellia oleifera

This study intended to help illustrate the Mn accumulation ability of Camellia oleifera and provide it as a novel species for possible use in Mn-contaminated sites. Field surveys have been carried out on Mn accumulation in C. oleifera growing near Mn mining area in Hezhou. Pot growth experiments in soil and sand culture were conducted to investigate Mn tolerance, accumulation, and translocation patterns in C. oleifera. C. oleifera grew well and showed no symptoms of Mn toxicity at a Mn treatment level below 1026 mg kg−1 in soil culture and 15.0 mmol L−1 in sand culture. Mn concentrations in leaves and stems reached a maximum of 9612.8 ± 83.5 and 6134.8 ± 94.0 mg kg−1, respectively, in soil culture and 28,465.8 ± 1276.7 and 15,398.4 ± 1148.6 mg kg−1, respectively, in sand culture. Meanwhile, most of the Mn taken from the substrates was transported to the aboveground tissues in soil and sand culture, e.g., over 92.07% of the total Mn taken up by C. oleifera was translocated to shoots in the 10.0 mmol L−1 treatment. Our findings confirmed that C. oleifera exhibited extraordinary Mn accumulation and toleration abilities, and C. oleifera was a suitable species for phytoremediation of Mn-contaminated sites in Guangxi Province.