Evaluation of Cadmium Uptake and Growth Inhibition of Three Turfgrass Species.
Yu-Jen Kuo, Chinese Culture University, 55, Hwa-Ken Rd, Taipei, Taiwan
Pollution of water and soil by heavy metals deposited in mining and industrial area is an environmental problem in many areas in Taiwan. Three potentially hyperaccumulating turfgrass species of centipedigrass (Eremochloa ophiuroides), common carpetgrass (Axonopus affinis), and perennial ryegrass (Lolium perenne) were screened by using solution cultural method in this study.Four levels of Cadium chloride (CdCl2), including 0, 10, 50 and 100 ppm were applied on the turfgrasses with 3 fully expanded leaves at age12 days. From the results we found that the plant dry weight, per unit water content of leaf, and chlorophyll a and b, were decreased by CdCl2. Perennial ryegrass showed the best performance under 100 ppm CdCl2 treatment if compared to the other 2 species at the same level of CdCl2. However, common carpetgrass showed the worst performance under this high level of CdCl2 treated environment. However, we found that the Cd accumulation in plants was increased when CdCl2 concentration increased. The Cd was mostly accumulated on root portions than shoot portions. Interestingly, the common carpetgrass absorbed the Cd metal more quickly than other species. We think that tolerance of turfgrass species to Cd metal was due to both genomic variation and plant growth characteristics. In this study, solution cultural system showed a potentially useful method for pre-screening putative heavy metal tolerant turfgrasses before commercialization for phytoremediation to clean up contaminated soils.