Abstract:
Objective To evaluate the antimony tolerance of 10 different clones of Catalpa bungeiso for providing plant materials for the remediation of antimony contaminated soil.
Method Under different antimony stress, the growth, biomass, leaf chlorophyll content, antimony content, leaf anatomical structure, hydrogen peroxide content, superoxide anion content, glutathione, and antioxidant enzyme activities (CAT, POD, APX) of different clones were determined. The antimony tolerance of 10 different clones was evaluated by factor analysis.
Result The results showed that under different concentrations of antimony stress, there were significant differences in aboveground and root biomass except 8402. The plant height and ground diameter of most clones increased firstly and then decreased with the increase of sb concentration. The root biomass of clone 8402 and 72, was higher than that of the control. Under the sb concentration 2 000 mg·kg−1, the other clones promoted the increase of the root biomass under low antimony concentration, and gradually decreased with the increase of antimony concentration to a certain concentration. Antimony was mainly accumulated in root. Under concentration 600 mg·kg−1, clone 63 had the highest antimony content in roots and leaves, and 8402 had the highest antimony content in stems. Under 1 200 mg·kg−1, clone 5-2 had the highest antimony content in roots,1-1had the highest antimony content in the stem and leaf . Under 2 000 mg·kg−1, the highest antimony content in roots, stems and leaves was clone 5-8,8402 and 72, respectively. There was a positive correlation between the activity of antioxidant enzymes and the concentration of reactive oxygen species in plants under certain antimony stress.
Conclusion The comprehensive evaluation of antimony tolerance of 10 Catalpa bungei clones under 0-2 000 mg·kg−1 antimony stress is clone 5-8 > 0 > 20-01 > 2-8 > 5-2 > 63 > 8402 > 1 > 72 > 1-1. The results provide plant materials for the remediation on antimony contaminated soil, and can improve the remediation effect of antimony contaminated soil. Under 2 000 mg·kg−1 antimony concentration in soil, Catalpa bungei clones with strong antimony tolerance can be used for remediation.