Cadmium uptake by different rice genotypes that produce white or dark grains

Article type: Research Article

Authors: CUI, Yu-jing | ZHU, Yong-guan^; | Smith, F. Andrew | Smith, Sally E.

Affiliations: Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China | Soil and Land Systems, School of Earth and Environmental Sciences, The University of Adelaide, SA 5005, Australia

Note: [] Corresponding author. E-mails: ygzhu@mail.rcees.ac.cn; yujing3@yahoo.com

Abstract: A pot experiment was conducted to investigate cadmium (Cd) uptake by different rice cultivars that produce white or dark grains. Four cultivars with white grains (hereafter, white rice) and five cultivars with dark colors (hereafter dark rice) were selected for this experiment. Three levels of soil Cd concentrations were used, background (0), 5 and 10 mg/kg. After harvest, plant biomass, tissue concentrations of Cd, Ca, Fe, Cu and Zn were analyzed. The results showed that Cd concentrations are significant different between different genotypes, but when comparing the Cd concentrations for the two groups, no significant difference was found. For other divalent cations, Ca concentrations in dark rice were higher than those in white ones (P<0.001 for shoots, P = 0.037 for roots); Fe concentrations in dark rice were also higher than those in white ones (P = 0.001 either in shoot or root); Zn concentrations in shoot of dark rice were higher than those in white ones, but no significant difference in roots. The total molar concentrations of divalent cations in dark rice were also significantly higher than in white rice. The potential benefit of higher Ca and Fe concentrations in dark rice and similar Cd concentrations in both groups is also discussed in this paper.

Keywords: cadmium, nutrient deficiency, plant nutrition, rice, dark grain, soil contamination

Journal: Journal of Environmental Sciences, vol. 16, no. 6, pp. 962-967, 2004