Lead stress-induced changes of antioxidant

controls. Calotropis procera and Ipomea purpurea showed highest decrease in

ascorbicacidoxidase activity by 68% and lowest is seen in Parthenium histocarpus

(6%) followed by Anisomilius molabarica (67%) , Eichornia fasculata (63%)

and Bromus tectorum (59%).compared with controls (Fig. 6). Our results accord

with previous researches under Pb stress in ascorbicacidoxidase from findings of

fig. 5 and 6: Effects of Pb concentration on

ascorbic acid oxidase activity and lipid peroxidation levels

Anuradha et al., (2007) in radish, Ibrahim et al., (2013) in alfalfa under cobalt and

copper toxicity and cucumber plants due to arsenate toxicity according to Czech

et al., (2008). Ascorbicacidoxidase seems more important due to its role in plants

not only as an antioxidant, but also as a signal molecule in many developmental

and defense responses.

fig. 7: Effects of Pb concentration on Starch content

Int. J. Bioinformatics and Biological Sci.: v.2 n.1&2, p. 13-22. March & June 2014

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