Arsenic uptake and distribution in Cucumis melo and Citrullus lanatus plants

Abstract

The use of groundwater with high arsenic (As) content in agricultural irrigation is a regular practice in many regions of the world, which results in the accumulation of As in soils to levels that can alter their physicochemical properties, decrease fertility, and reduce crop yield. Plants absorb many elements from soil and irrigation water. Some of these elements have a biological function but others can be toxic to the plants such as As. The presence of As in plants pose a risk due to the possible bioaccumulation of this metalloid through the trophic chains. The uptake, biotransformation, and bioaccumulation mechanisms of As occurring in plants is substantially affected by plant species and genotypes. The effects and distribution of As in melon (Cucumis melo) and watermelon plants (Citrullus lanatus) irrigated with As in a soil mesocosm were evaluated. The accumulation of As for Cucumis melo and Citrullus lanatus is presented according to the following: root > leaf > stem. In a period of 35 weeks with 1.4 mg L 21 of As concentration in irrigation water, adverse effects on the development of both genotypes were observed. For these As concentrations, Citrullus lanatus showed a clear reduction of root growth.

Arsenic accumulation in lentil (Lens culinaris) genotypes and risk associated with the consumption of grains

“…The transportation and accumulation of As in plants followed the order, roots > shoots > grains 40,41 . Arsenic contamination in growing media (0.2 mg kg −1 ) causes negative effects on food crops 42,43 . Similarly, 0.6 mg kg −1 As in soil affected soybean growth 44 .…”

Mechanisms of arsenic assimilation by plants and countermeasures to attenuate its accumulation in crops other than rice

“…Apart from the threat due to the presence of arsenic in drinking water, the use of groundwater with high levels of this metalloid for irrigation purposes and the weathering of the parent material in diverse geographical areas have led to the accumulation of As in soils and, ultimately, to increased transfer of the metalloid into the food chains (Singh et al, 2015;Islam et al, 2017). For instance, in cereal crops, legumes and vegetables, the concentration ranges of accumulated As has been reported to amount to 0.07-0.83, 0.02-0.56 and 0.001-0.039 mg kg −1 , respectively (Pineda-Chacón and Alarcón-Herrera, 2016). Some estimates have suggested that the daily amount of arsenic consumed per capita may reach values as high as 0.9 mg (Butcher, 2009) and, according to the WHO, this value of daily intake is very close to the maximum tolerable limit (Williams et al, 2005).…”