Cadmium Accumulation and Translocation in Two Jerusalem Artichoke (Helianthus tuberosus L.) Cultivars

Jerusalem artichoke (Helianthus tuberosus L.) not just can be used for bioethanol production but may be potentially used in phytoremediation for the removal of heavy metal pollutants. Two Jerusalem artichoke cultivars, N2 and N5, were subjected to six cadmium (Cd) concentrations (0, 5, 25, 50, 100 and 200 mg L-1) to investigate Cd tolerance and accumulation. After 21 days of growth, the effects of Cd on growth, chlorophyll content, net photosynthetic rate, intercellular CO2 concentration and malondialdehyde content were evaluated. Most growth parameters were reduced under Cd stress. The two Jerusalem artichoke cultivars had relatively high Cd tolerance and accumulation capacity (> 100 mg Kg(-1) with N5 being more tolerant and having higher Cd accumulation than N2. Roots accumulated more Cd than stems and leaves. The bioconcentration factors (far higher than 1) and translocation factors (lower than 1) decreased with an increase in Cd applied. The results suggested that Jerusalem artichoke could be grown at relatively high Cd loads, and N5 could be an excellent candidate for phytoremediation of Cd-contaminated soils.