AN IN VITRO STUDY OF BIOCHEMICAL CHARACTERIZATION AND AMELIORATING EFFECT OF POLYETHYLENE GLYCOL AGAINST CD STRESS IN SUGARCANE

摘要

Polyethylene glycol is considered as an important antioxidant which plays important role in defence mechanisms of plants. The ameliorating role of PEG against Cd stress under in ^itro conditions was studied in callus cultures of Saccharum sp. (cvs. HSF 240). Callus induction and proliferation was carried out on MS medium supported with 2, 4-D and NAA either alone or in combination with BAP and Kinetin. Cd stress (0.1-0.5 mM) was applied to well proliferated calli. By increasing the concentration of Cd stress, average weight of callus was decreased and complete necrosis occurred at 0.5 mM after 30 days of Cd stress. Specific activities of catalases, peroxidises, PAL, total soluble protein contents and total amino acid contents were maximum at 0.4 mM of Cd. Well proliferated calli were pre-treated with 1 PEG for 24 hours to combat the effect of Cd stress. PEG minimize the effect of Cd stress on average callus weight, specific activities of catalases, peroxidises, PAL, total amino acid contents, total soluble protein contents. At higher concentration of Cd stress (0.4mM), PEG failed to show ameliorating effect.