Arsenic (As) contamination in rice has become a global concern as a potential dietary risk to human health. A pot culture experiment was conducted in the net house of the Department of Soil Science, Bangladesh Agricultural University (BAU), Mymensingh to study the effect of soil As contamination on rice (BRRI dhan47) and its management through water regimes. Treatment combinations were made with three rates of As(0, 20 and 40 mgkg-1) in combination with two water management practices viz. alternate wetting and drying (AWD) and continuous flooding (CF). The experiment was laid out in a completely randomized design (CRD) with 3 replications. Pots were filled with 10 kg soil collected from the Soil Science Field Laboratory, BAU with background soil As 3.73 mgkg-1. Results showed that As contamination significantly reduced growth and yield of rice. The grain and straw arsenic concentrations were 0.55 and 17.31 mgkg-1, respectively in soil treated with As 40mgkg-1 while 0.18 mgkg-1 grain As and 2.41 mg kg-1 straw As were found in As 0mgkg-1 treatment. The AWD technique significantly reduced grain As concentration by 14% compared to CF with significant increase in grain yield. Straw As concentration, grain As uptake, and total As uptake were also significantly reduced by AWD practice. Thus, AWD rice cultivation can be a potential and sustainable technology to mitigate arsenic problem in rice in As-contaminated areas.
Key words: arsenic, rice, alternate wetting and drying, continuous flooding.
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