The evaluation of resistance to Co 2+ of lawn plant at seedling stage and its concentration property at adult stage

In order to evaluate the resistance of lawn plant to Co at germination stage and discuss its concentration property at adult stage, four kinds of lawn plant which have some growth advantages in Co polluted environment were selected as experimental materials in this research. They are tall fescue, timothy grass, inflorescences, and annual ryegrass. The results show that the evaluation of resistance to Co of tall fescue's seed is the highest; the evaluation of resistance to Co of annual ryegrass seed is the lowest. The low consistence Co could improve the seed germination. With Co concentration increase, the accumulation coefficient of four plants increased at first and decreased later; the accumulation coefficient of underground portion is higher than the accumulation coefficient of aboveground; with Co concentration increase, the transfer coefficient of four plants have a remarkable decline. In these plants, the accumulation coefficient of tall fescue and annual ryegrass is bigger than other two plants. As the concentration of Co treatment increased to 100 mg/kg, the aboveground enrichment of Co in F. elata reached 75 mg/kg, followed by L. multiflorum (68.9 mg/kg), P. pratense (48.8 mg/kg), and D. glomerata (27.2 mg/kg).The highest underground enrichment of Co in F. elata reached 836.46 mg/kg, in contrast to the lowest underground enrichment in D. glomerata, 264.67 mg/kg. It shows that fescue and annual ryegrass have a better enrichment property to Co and have a better prospect for the treatment of cobalt-contaminated soil. This research could provide some scientific basis and main technical approach for the soil contaminated by Co .