Abstract
Cd-hyperaccumlulation is a rare phenomenon and only several wild plants are known as a Cd-hyperaccmumulator. The mechanisms involved in Cd-hyperaccumulationi are little understood. In our previous work, Avena strigosa was indicated as a novel Cd-accumulating crop with superior tolerance against Cd. We herein characterized the abilities of Cd accumulation and tolerance in different cultivars of A. strigosa and A. sativa. Plants were grown hydroponically in a growth chamber for 3 weeks and then, treated with ranged concentrations of Cd (0-100μM). Total Cd concentrations and Cd-distribution to the cell wall fraction were analyzed by ICP-MS. One cultivar of A. strigosa exhibited greater Cd accumulation in the leaves than other oats, sorghum and rice without showing toxicity. In leaves of this cultivar, superior capacity of apoplastic Cd accumulation as well as unknown vacuolar transport systems, were suggested to play a significant role in Cd tolerance.
