5. Conclusions
Rice plants grown in alfisol accumulated more Cd compare with vertisol. This effect was mainly because of difference in cation exchange capacity and alkalinity of soils chosen. Physiochemical properties of soil such as micronutrient content, total organic carbon,
and texture had minor role in above result. Difference in Cd accumulation also reflected as alteration of ecophysiological components such as biomass, relative water content and nonphotochemical quenching. These components were lower in alfisol compare with vertisol. During Cd treatments; plants grown in vertisol produced more flavanoids, sugar, protein, chlorophyll and anthocyanin compare to alfisol. But phenolic content was more in alfisol grown plants compare with those grown in vertisol. Alterations in some of ecophysiological functions were independent from soil types. These include increase in quantum efficiency of
PS II, thiols, and silicon as well as decrease in carotenoids, and calcium content. It was also revealed that MTU 7029 having adaptability to varying nutrient management practices accumulate more Cd than MO 16. Statistically significant difference in Cd accumulation
between plants grown in alfisol and vertisol along with difference in ecophysiological components points that these components represent potential ecophysiological markers that indicate Cd accumulation in rice grow in alfisol and vertisol.
Acknowledgements
Authors gratefully acknowledge the help received from Central Instrument Laboratory and School of Chemistry; University of Hyderabad for EDS and FTIR analysis respectively. Abin Sebastian acknowledges junior research fellowship received through CSIRUGCNET.
Appendix A. Supplementary material
Supplementary data associated with this article can be found, in the online version, at http://dx.doi.org/10.1016/j.chemosphere.2014.02.077.