Strontium uptake and antioxidant capacity comparisons of low accumulator and high accumulator oat (Avena sativa L.) genotypes.

The main object of the present study is to investigate genotypic differences in strontium (Sr) resistance of two oat varieties, including Neimengkeyi-1 (high accumulator) and Bayou-3 (low accumulator). The growth and antioxidant enzyme responses to five Sr concentrations (0, 25, 100, 500, and 1000 mg kg^-1) were compared after 30-day Sr treatment. The shoot-Sr concentrations of Neimengkeyi-1 were higher than those of Bayou-3 in all treatments. The translocation factors of Neimengkeyi-1 in all treatments were greater than 1 and significantly higher than those of Bayou-3. Sr ions did not affect the growth of Neimengkeyi-1. The H₂O₂ contents and the leaf malondialdehyde contents of Neimengkeyi-1 were lower than those of Bayou-3. The activities of superoxide dismutase (SOD), catalase (CAT), and peroxidase of Neimengkeyi-1 were significantly higher than those of Bayou-3. Significant negative correlations were found between H₂O₂ contents and SOD and CAT activities in Neimengkeyi-1. The results of this study suggest that Sr accumulation patterns have significant genotypic differences, and SOD and CAT may play a pivotal role in the detoxification mechanism of Sr.