A Kinetic analysis of cadmium accumulation in a Cd hyper-accumulator fern, and tobacco plants

吉原 利一*; 鈴井 伸郎; 石井 里美; 北崎 真由*; 山崎 治明*; 北崎 一義*; 河地 有木; 尹 永根; 七夕 小百合*; 橋田 慎之介*; et al.

Plant, Cell & Environment, 37(5), p.1086 - 1096, 2014/05

https://doi.org/10.1111/pce.12217

Cadmium (Cd) accumulations in a Cd hyper-accumulator fern, (), and tobacco, (), were kinetically analysed using the positron-emitting tracer imaging system under two medium conditions (basal and no-nutrient). In , maximumly 50% and 15% of the total Cd accumulated in the distal roots and the shoots under the basal condition, respectively. Interestingly, a portion of the Cd in the distal roots returned to the medium. In comparison with , a little fewer Cd accumulations in the distal roots and clearly higher Cd migration to the shoots were observed in under the basal condition (maximumly 40% and 70% of the total Cd, respectively). The no-nutrient condition down-regulated the Cd migration in both species, although the regulation was highly stricter in than in (almost no migration in and around 20% migration in ). In addition, the present work enabled to estimate physical and physiological Cd accumulation capacities in the distal roots, and demonstrated condition-dependent changes especially in . These results clearly suggested occurrences of species-/condition-specific regulations in each observed parts. It is probable that integration of these properties govern the specific Cd tolerance/accumulation in and .