3.2. Effects of Silicon on total Arsenic concentrations in rice genotypes with different ROL
The concentrations of Arsenic were under detection limits in rice plants (including the parts of shoot and root) grown in the −As treatment (results are not shown). Rice genotypes had significant influences (p < 0.001) on shoot and root total As concentrations (Table 3). The shoot Arsenic concentration of six genotypes grown in −Si +Arsenic treatment ranged from 2.13 to 3.82 mg/kg with the ranking of XFY-9 > SY-9586 > FYY-299 > TY-207 > XWX-12 > XWX-17, while the root As concentration ranged from 85.14 to 147.8 mg/kg with the ranking of TY-207 < XFY-9 < SY-9586 < FYY-299 < XWX-12 < XWX-17 (Table 3). It is worthwhile mentioning that the shoot total As concentration in XFY-9 (3.82 mg/kg) with the lowest rate of ROL was higher than that in XWX-12 (2.2 mg/kg) with the highest ROL, while the root total As concentration in XFY-9 (86.83 mg/kg) was 42.4 mg/kg lower than that of XWX-12 (129.23 mg/kg) in −Si+As treatment (Table 3).