Arsenic accumulation analysis
Shoot and root samples from plants grown on media containing 20 µM AsIII
for 3-weeks were harvested separately. The samples were washed with 10
mM sodium-EDTA to remove excess As adsorbed on surface and then rinsed
twice with DI water. The samples were then dried at
70oC for 48 hours. Dried samples were weighed, roughly
crushed, and digested using concentrated nitric acid (15.8N) and 30%
hydrogen peroxide (H2O2) on a heat block
digester at 115oC for 45 minutes. Digested samples
were then diluted and analyzed for arsenic using ICP-MS (ICPMS-2030,
Shimadzu Corporation, Nakagyo-ku, Kyoto, Japan). Translocation factor
from root to shoot was calculated using this formula: TF = As
concentration in shoot/ As concentration in root