Effect of Lead Toxicity on Growth, Chlorophyll and Lead (Pb+) Contents of Two Varieties of Maize (Zea mays L.)
Two varieties of maize (Zea mays L.) (Neelam and Desi) were exposed to different concentrations of lead [0, 10, 20 and 30 ppm Pb(NO3)2•4H2O] for 14 days in earthen pots. Exposure of maize varieties to excess Pb resulted in a significant root growth inhibition though shoot growth remained less affected. The results of chlorophyll analysis indicated that the highly toxic Pb level affected photochemical efficiency in Neelam, while no significant effect was observed in the Desi. This result was related to the accumulation of Pb. The results of the present study indicated that, Desi withstands excess Pb with its higher Pb accumulation capacity in roots and better upregulated protective mechanisms compared to Neelam. Therefore, Desi is more tolerant to Pb toxicity compared to Neelam which was found to be susceptible variety.