Impact Of Arsenic on Pisum sativum and Its Amelioration Using Phosphate

Abstract

The study examines the impact of arsenic on seed germination and seedling growth of Pisum sativum (pea) across different concentrations of Arsenic from 0 to 30 ppm and evaluates the mitigating role of phosphate for arsenic toxicity. The germination experiment was carried out with six seeds per Petriplate in triplicate across six arsenic concentrations (with and without phosphate), yielding 36 plates for each kind of medium. The toxic heavy metal significantly reduced germination rates (70.6-2.3%), root (4.83-0.76cm) and shoot lengths (3.04- 0.5cm), fresh cotyledon (0.48-0.53g), root (0.13-0.002g) and shoot (0.11-0.01g) weight and dry root (0.44-0.012g), shoot (0.10-0.03g) and cotyledon weights (0.33-0.36g) of plant with severe impacts at 20 ppm and above. Amendment with 40 ppm Phosphate greatly improved all the growth indices viz germination percentage (73.7-11.8%), root (6.45-1.38cm) and shoot (4.45-1.94cm) length, fresh cotyledon (0.53-0.57g) root (0.28-0.041g) and shoot (0.28-0.10g) weight and dry root (0.05-0.02g), shoot (0.14-0.047g) and cotyledon weights (0.415-0.43g) enhancing plant resilience to arsenic stress from 0-30 ppm concentration. However, at higher concentrations, the toxic effect of As was more pronounced, and the addition of 40ppm Phosphate helps the plant to bear the toxicity of As at lower concentrations, highlighting the potential of amendments in managing contamination.