Differences in root surface adsorption, root uptake, subcellular distribution, and chemical forms of Cd between low- and high-Cd-accumulating wheat cultivars
- 58 Downloads
The differences in the mechanism of cadmium (Cd) accumulation in the grains of different wheat (Triticum aestivum L.) cultivars remain unclear. Thus, we conducted a hydroponic experiment in a greenhouse to compare root surface adsorption, root uptake, subcellular distribution, and chemical forms of Cd between low- and high-Cd-accumulating wheat cultivars at seedling stage, to improve our understanding of the differences between cultivars. The results showed that Cd adsorbed on the root surface was mainly in a complexed form, and the total amount of Cd on the Yaomai16 (YM, high-Cd-accumulating genotypes) root surface was higher (p < 0.05) than that on Xinmai9817 (XM, low-Cd-accumulating genotypes). A large amount of Cd ions adsorbed on root surface would cause plant damage and inhibit growth. Comparing the root-to-shoot translocation factors of Cd, the transfer coefficients of YM were 1.017, 1.446, 1.464, and 1.030 times higher than those of XM under 5, 10, 50, and 100 μmol L−1 Cd treatments, respectively. The subcellular distribution of Cd under Cd exposure is mainly in the cell wall and soluble fraction. The proportions of Cd in YM shoot soluble fraction were higher than those in XM, which was the main detoxification mechanism limiting the activity of Cd and may be responsible for low Cd accumulation in grains, while the effects of the chemical forms of Cd on migration and detoxification were not found to be related to Cd accumulation in the kernels.
KeywordsWinter wheat Cadmium Adsorption Subcellular distribution Chemical forms
The author would like to extend their sincere gratitude to the Agriculture Water and Soil Environment Field Science Research Station, China, for the permission to carry out the research.
Y.-T.X. performed the experiments and drafted the manuscript. Z.-J.D. and X.-B.Q. provided some guidance in the experiments, and H.-Q.W., W.G., and D.-F.W. have contributed in the analysis of the data and further modifications of the manuscript. All authors read and approved the final version of the manuscript.
Financial support for this research was provided by National Natural Science Foundation of China (Grand No.51779260, 51679241, 51709265), the National Key Research and Development Program of China (2016YFD0800703), and the Central Public-interest Scientific Institution Basal Research Fund (Farmland Irrigation Research Institute, CAAS, FIRI2017-13).
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
- Blum A, Sullivan CY (1997) The effect of plant size on wheat response to agents of drought stress. 1. Root drying. Aust J Plant Physiol 24:35–41Google Scholar
- Liu ZD, Zhou Q, Hong ZN, Xu RK (2017) Effects of surface charge and functional groups on the adsorption and binding forms of Cu and Cd on roots of indica and japonica rice cultivars. Front Plant Sci 8:9Google Scholar
- Zhang Y, Yang X (1994) The toxic effects of cadmium on cell division and chromosomal morphology of Hordeum vulgare. Mutat Res Environ Mutagen Relat Subj 312:121–126Google Scholar