Abstract
We investigated the effect of temperature on copper (Cu) extraction by the two kinds of plants of Brassica juncea Coss. and Zea mays L. These plants were grown in Cu-amended decomposed granite soil (DG soil, 29μg Cu g-1) and volcanic ash soil (Andosol, 292μg Cu g-1) under the temperature condition of 15, 20, 25 and 30°C for 3weeks in the phytotron. For Z. mays, the amount of Cu extraction was the same in both DG soil and Andosol, whereas for B. juncea it was more in the DG soil than in the Andosol. This suggests the difference in the Cu-accumulation ability between these plants. The highest Cu accumulation has achieved by Z. mays grown in the Andosol at 30°C. In lower temperature condition, B. juncea did not exceed Z. mays in terms of Cu accumulation for both soils. Since B. juncea had more plant density in field, the Cu accumulation per unit area could be higher in B. juncea than in Z. mays at low temperature condition. For the more effective extraction of Cu from the polluted soil, it is necessary to select the optimum plant that conforms to temperature during the cultivation.
