Arsenic accumulation in paddy plants at different phases of pre-monsoon cultivation. (November 2018)

• Record Type: Journal Article
• Authors: Chowdhury, Nilanjana Roy; Das, Reshmi; Joardar, Madhurima; Ghosh, Soma; Bhowmick, Subhojit; Roychowdhury, Tarit
• Is Part Of: Chemosphere. Volume 210(2018)
• Page Start: 987
• Page End: 997
• Publication Date: 2018-11
• Subjects: Paddy field -- Boro cultivation -- Groundwater -- Arsenic -- Paddy plant -- Growing phases; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2018.07.041
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: Geogenic arsenic (As) contamination in Bengal Delta Plain is a growing environmental and research concern. Cultivation of staple crops like paddy on these contaminated fields is one of the major routes for human dietary exposure. The present study investigates changes of arsenic concentrations in paddy plant parts, root soil and surface soil throughout the various phases of pre-monsoon ( boro ) cultivation. Arsenic uptake property of paddy plants collected from 10 fields was found to be dependent on the variety of paddy plant (like Minikit, Jaya ) rather than arsenic levels in groundwater (0.074–0.301 mg/l) or soil (25.3–60 mg/kg). Arsenic is translocated from root to aerial parts in descending order. Leaf, stem, root, root soil and surface soil showed a similar trend in their change of arsenic concentration throughout the cultivation period. Arsenic concentration was highest in vegetative phase; sharply declined in reproductive phase; followed by moderate increase in ripening phase. The young root tissues in vegetative (primary) phase could uptake arsenic at a much faster rate than the older tissues in later phases. With the growth of the plant, higher concentrations of iron in root soil in the reproductive phase confirmed the formation of iron plaques on the surface of the root, which sequester arsenic and prevented its uptake by plants. Finally, co-precipitation of arsenic with iron released from crystallized iron plaques results in loosening of the iron plaques from root surface. Thus, soil arsenic concentration increases in the final phase of cultivation which in turn contributes to increased concentration in plant parts. Graphical abstract: Image 1 Highlights: Arsenic(As) uptake of paddy plant depends on cultivar type apart from water, soil. As decreases from vegetative to reproductive phase then increases in ripening phase. Fe plaque in root soil sequesters As, lowering translocation at reproductive phase. As co-precipitates with Fe in soil increasing bioavailability in ripening phase.