ABSTRACT
Disruptions in plant growth, metabolism and loss in yield caused by lead are issues of great concern. In this study, morphological and biochemical responses under lead stress were examined to screen the tolerant cultivar of Cyamopsis tetragonoloba (cluster bean). All four cultivars were exposed to 0 (control), 600, 800, and 1,000 mg/kg of lead. Our results demonstrated that Pb decreased the growth and photosynthetic pigments, while it enhanced the production of ascorbate peroxidase and catalase in all cultivars. In comparison to control, there is little variation in growth indices at 600 mg/kg. Moreover, the maximum content of Pb was found in roots (336.92 mg/kg) followed by the stem (124.19 mg/kg) and leaves (47.45 mg/kg), while the maximum reductions of ETRmax, i.e. 36.65% and ΔF/Fm′, i.e. 27.48%, were observed in RGC 1055 during vegetative stage at 800 mg/kg of Pb. The cultivar RGC 1066 was found to be more tolerant to Pb stress because of its higher biomass, photosynthetic rate, antioxidant activity and low Pb content, and this resulted in less oxidative damage. As the cultivar RGC 1055 accumulated a higher amount of Pb in comparison to RGC 1066, this cultivar can also be used in phytoremediation. By selecting these two cultivars, we are working on the remediation strategy for Pb toxicity using an elicitor.
Acknowledgments
The infrastructure and research facilities provided by Prof. Aditya Shastri, Vice-Chancellor Banasthali Vidyapith are gratefully acknowledged.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Author contribution
YS, NK and VS designed the experiment and wrote the manuscript. YS carried out the experimental work.
Supplementary material
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