Uptake of Thallium from Artificially Contaminated Soil into Brassica oleracea acephala L.
A method to monitor inductively coupled plasma atomic emission (ICP-AE) was used for analysis of available thallium in the soil and hyperaccumulated thallium in three kale cultivars (Winterbor, Redbor, and Reflex). The soils were artificially contaminated in increments ranging from 0-300 ppm. Half of the 150 pots (with 1-2 plants per pot) were also spiked with potassium to investigate the relationship between thallium and potassium. There was no significant competitive inhibition between potassium and thallium for the two cultivars, Winterbor and Reflex. At high levels of available thallium, there appeared to be competitive inhibition for Redbor. I also found that Redbor, a cultivar not previously studied, is a moderate hyperaccumulator of thallium and that thallium seems to be toxic when the plant reaches concentrations between 40 and 120 ppm. iii