The aim is to analyze the Pb-tolerance of three commonly found tree species and determine the Pb-toxicity and impacts of Pb on growth, physiological and biochemical parameters. In the present study, we examine the response of Pb-induced stress in three commonly growing tree species i.e., Terminalia arjuna, Cassia fistula, and Pongamia pinnata based on various characteristics at an interval of 90?days for 360?days. Plant seedlings were exposed to 0 (control), 200, 450, and 600?mg of Pb/kg dry soil. Our results showed that Pb significantly reduced growth, photosynthetic pigments, and physiological parameters in all studied species. These reductions were highest in P. pinnata followed by C. fistula, and T. arjuna. Besides, Pb-induced toxicity caused many fold rise in biochemicals such as malondialdehyde, proline, phenolics, thiols, and others. These elevations were highest in T. arjuna followed by C. fistula and P. pinnata. Further, it was also observed that with an increase in the number of days of year (DOY) of Pb exposure, plants showed a reduction in physiological parameters but an increase in growth and biochemical parameters in all studied species. Furthermore, the physiological parameters showed a negative and the biochemical parameters showed a positive correlation with both DOY and treatments, while the growth parameters showed a negative correlation with treatments and a positive correlation with DOY. Hence, we can conclude that the three selected species are promising candidates to be recommended for plantation in Pb-polluted urban areas due to their Pb-tolerance. Overall, the study provides a better understanding of the impacts of Pb on tree species in the long-term and in assessing their potential for sustainable plantations in urban areas. Highlights ? Pb reduced growth, and affected physiology and biochemistry in all studied species. ? P. pinnata was most affected followed by C. fistula and T. arjuna. ? Physiology was diminished with the number of days of Pb exposure and treatments. ? Physiology had negative and biochemistry had positive correlation with Pb exposure. ? Growth was decreased due to Pb exposure but increased with number of days.

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