PHYTOTOXICITY OF CADMIUM AND ITS EFFECT ON TWO GENOTYPES OF BRASSICA JUNCEA L.

Abstract

By using two Brassica juncea, L. (Indian mustard) genotypes (Varuna and DHR-9504) agreenhouse experiment was carried out to study the effect of cadmium (Cd) on growth, yield and concentration of cadmium (Cd) in different plant parts at the Agricultural Research Station, Bilaspur Chhattisgarh, India during 2002-2003. Plants were grown under controlled climatic conditions and subjected to increasing Cd supply in the form of CdCl2 @ 0, 20, 40, 60, 80 and 100 mg Cd kg-1 soil. Cdphytotoxicity was shown by growth retardation of Varuna and DHR-9504. Varuna showed greater sensitivity to Cd toxicity than DHR-9504. Increasing Cd supply markedly reduced the seed, stem and root dry weight of both genotypes (Varuna and DHR-9504), and these decreases were more marked in Varuna.Due to increased level of Cd application, the Cd concentration increased significantly in various plant parts in both the Brassica genotypes tested. Increase in Cd concentration of about 5 times in seeds, 7 times in stems and 9 times in roots was noted with an application of 20 mg Cd kg-1 soil more than the control. Cd was accumulated in the roots in much higher amounts than in the stem and seeds, especially in the case of DHR-9504, indicating that there is limited transport of Cd from the root system to the above ground plant parts in DHR-9504 genotype due to the presence of strong Cd-binding proteins in the roots. GenotypeDHR-9504 had significantly less uptake of Cd than genotype Varuna. More data are needed to ascertain the findings of this study.