Arsenic and cadmium phytoextraction potential of crambe compared with Indian mustard

The ability to tolerate and accumulate arsenic (As) and cadmium (Cd) was compared between Brassica juncea (Indian mustard) and Crambe abyssinica (Hochst.) (crambe or Abyssinian mustard). Plants were grown hydroponically and treated with 70 mu M sodium arsenate or 50 mu M cadmium chloride for two weeks. When nutrients were omitted during the As treatment, leaves of C. abyssinica accumulated an average of 140 mg As kg(-1), compared with 34 mg kg(-1) for B. juncea. When quarter-strength Hoagland's nutrient solution was provided during As treatment, leaves of C. abyssinica accumulated an average of 270 mg As kg(-1), compared with 13 mg kg(-1) for B. juncea. Cadmium accumulation on a dry-weight basis was approximately two times greater in shoots of B. juncea. Shoot biomass production in the presence or absence of metals was greatest for C. abyssinica. Because of its larger biomass and more efficient accumulation of As, C. abyssinica should be considered for use in phytoremediation research.