Elucidating the role of atmospheric deposition on uptake and subcellular distribution of As, Cd, and Pb through root in A. paniculata

Abstract

The present study examined the impact of atmospheric deposition on the accumulation, translocation, and subcellular distribution of As, Pb, and Cd via root in A. paniculata. Two experimental conditions were set in the study: i. Plants grown in metal-contaminated and without metals-contaminated soils were exposed to atmospheric deposition, and ii. Plants grown in metal-contaminated and without metals-contaminated soils were not exposed to atmospheric deposition. The PM10 in the air and dry deposition on the surface of leaves were collected and characterized. The uptake kinetics and subcellular distribution of As, Cd, and Pb, growth parameters, stress enzymes, and nutrient content in plants were also investigated. The PM10 concentration at the site varied between 142 and 469 μg/m3 and demonstrated the presence of Al, B, Ba, Ca, Cu, Fe, K, Mg, Mn, Zn, Pb, As, and Cd. The dry deposition on leaves displayed the presence of Pb, Cd, Al, B, Ba, Ca, Cu, Fe, K, Mg, Mn, and Zn. Results displayed no translocation of atmospheric Pb and Cd from leaves to stem and root in plants but increased uptake velocity and binding affinity of As, Cd, and Pb in the stem and root tissues from soil. An increase in As, Cd, and Pb content in the cell wall and organelle portion of all plant tissues was observed after atmospheric dust exposure. Alterations in the stomata opening and aperture size in leaves and reduction in plant growth and secondary metabolite content were observed after atmospheric dust exposure.