Irrigation management and variety effects on rice grain arsenic levels in Uruguay
journal contributionposted on 2019-01-01, 00:00 authored by Gonzalo CarracelasGonzalo Carracelas, John HornbuckleJohn Hornbuckle, M Verger, R Huertas, S Riccetto, F Campos, A Roel
Rice is the most important staple component of the human diet worldwide. The higher amounts of arsenic accumulation in its grain in relation to other crops, determines a potential toxicity risk to humans. This research project aimed to determine the inorganic arsenic accumulation in rice grain (iAs) in two contrasting soil sites, Paso Farias-Artigas (PF) and Paso de la Laguna-Treinta y Tres (PdL), with two different mitigation practices, in Uruguay. These being firstly irrigation management techniques and secondly the use of different varieties. Five experiments were conducted with a split plot design with four blocks over three rice growing seasons from 2014 until 2017. The experimental sites included two irrigation treatments: continuous flooded (C) and alternate wetting and drying (AWD). The split plots included different varieties: Indicas and Japonicas. Average iAs accumulated in rice grain were 0.07 mg kg−1, well below international limits, even under the C irrigation technique. It was found that iAs accumulation in rice grain can be further reduced by the implementation of AWD in certain soil types. Japonica varieties had a lower accumulation of iAs in rice grain, in comparison with Indicas at both sites.