Cadmium tolerance and absorption characteristic of herbaceous plants

Thirty-five varieties of herbaceous plants were selected for studying tolerance and accumulation characteristics of cadmium in pot experiments using 10 mg·kg-1 cadmium treatments. The plants were grown under conditions sheltered from rain. We found that the herbaceous plants had good tolerance against 10 mg·kg-1 cadmium stress, and that the growth of only nine species was significantly inhibited in the experiment on herbaceous plants. In addition, root/shoot ratio decreased significantly (P<0.05) in two species only. Cadmium absorption and accumulation differed among the experimental plants, and the translocation capacity of leguminous plants and warm-season turfgrass were superior to that of cool-season turfgrass. The highest cadmium content in shoots and roots were found in Crowtoe (Lotus corniculatus) and Kentucky bluegrass (Poa pratensis), respectively. The highest cadmium translocation factor was found in Lyme grass (Elymus dahuricum). The result of clustering analysis based on cadmium accumulation in shoots indicated that two varieties of annual ryegrass (Lolium multiflorum) have the highest cadmium accumulation among the herbaceous plants studied.