关键词: 三叶鬼针草, 生态型, 混种, 镉积累

Abstract:

To study effects of interplantation ratio on cadmium accumulation of two ecotypes (farmland  and mining) of  Bi?dens pilosa, a pot  experiment, designed to have six  treatments in ratio, i.e.  1:4, 2:3, 3 :2, 4:1, farmland  ecotype only and mining ecotype only, and the soil spiked with 10 mg•kg^-1 cadmium, was conducted. Results demonstrate that as compared with their respective  treatments of  monoculture interplantation increased  the farmland ecotype  of B.  pilosa  bio?mass, but decreased the mining  ecotype of B. pilosa in biomass per plant, and significantly  increased the contents of chlorophyll a, chlorophyll b  and carotenoid in the two  ecotypes of B. pilosa,  and the concentration of  cadmium in various  or gans of the  two ecotypes of B. pilosa.  When the  interplantation ratio was 2:3  (farmland ecotype:mining ecotype),thecontent of cadmium was  the highest in all  organs of the  two ecotypes of  B. pilosa, and  the cadmium accumulation  in theshoots and the whole  plant in one pot  were also the highest, reaching up  to 422.08  and 477.91  μg•pot^-1  , respectively.To sum up, the interplantation of the two ecotypes of  B. pilosa at a ratio of 2 : 3  (farmland ecotype ∶  mining ecotype) may effectively improve the plants′ cadmium accumulation capacity, and consequently  the effect of the two ecotypes of B. pilosa remedying cadmium contaminated soils.

Key words:  Bidens pilosa, ecotype, interplantation, cadmium accumulation