Association of arsenic with nutrient elements in rice plants

Abstract

Rice is the main cereal crop that feeds half of the world's population, and two thirds of the Chinese population. Arsenic (As) contamination in paddy soil and irrigation water elevates As concentration in rice grains, thus rice consumption is an important As intake route for populations in south and south-east Asia, where rice is the staple food. In addition to direct toxicity of As to human, As may limit the accumulation of micro-nutrients in rice grains, such as selenium (Se) and zinc (Zn). These micro-nutrients are essential for humans, while mineral deficiencies, especially iron (Fe) and Zn, are prevalent in China. Therefore, it is important to understand the interactions between As and micro-nutrients in rice plants, which is the principal source of these nutrients for people on rice diets. In addition, during the processes of As uptake, translocation and transformation, the status of macro-nutrients (e.g. silicon (Si), phosphors (P), sulfur (S)) are important factors affecting As dynamics in soil-plant systems and As accumulation in rice grains. Recently, synchrotron-based spectroscopic techniques have been applied to map the distribution of As and nutrient elements in rice plants, which will aid to understand how As are accumulated, complexed and transported within plants. This paper reviews the interactions between As and macro-nutrients, as well as micro-nutrients in rice plants.

Arsenic accumulation in the roots of Helianthus annuus and Zea mays by irrigation with arsenic-rich groundwater: Insights from synchrotron X-ray fluorescence imaging

“…Most studies investigating the distribution and accumulation of As in plants have focused on rice (Oryza sativa), one of the world's most important cereal crops (Duan et al, 2013;Meharg, 2004). In general, the uptake and enrichment of As by plants depends on the individual physiology of each plant species as well as on the overall bioavailability of As in the surrounding soil (Mallick et al, 2011).…”

H2O2 pretreated rice seedlings specifically reduces arsenate not arsenite: difference in nutrient uptake and antioxidant defense response in a contrasting pair of rice cultivars

“…It is well established that most of the biotic and abiotic stress response results into generation of H 2 O 2, hence, priming rice seedlings with H 2 O 2 would induce a well developed antioxidative defence mechanism prior to As exposure, and treatment with H 2 O 2 + SA could also have additive effect, as the mode of SA in plants is through generation of H 2 O 2 . As exposure to rice interferes with uptake of mineral elements such as Cu, Zn, Fe, Ni and Se (Duan et al, 2013;Dwivedi et al 2012). However, there are no reports about the influence of the plant hormomes such as jasmonic acid, salicylic acid or molecules like H 2 O 2 on the uptake or translocation of these minerals in As challenged rice plants.…”

Effect of selenium fertilization on the accumulation of cadmium and lead in rice plants

“…Therefore, in plants, selenium can either act as an antioxidant or activate plant protective mechanisms, alleviating oxidative stress (Hartikainen et al, 2000;Pedrero et al, 2008;Kumar et al, 2012). As well as the protective effect against the toxicity, selenium can also affect the accumulation and distribution of toxic metals in plants (Zembala et al, 2010;Duan et al, 2013). It has previously been demonstrated that selenite significantly inhibited the translocation of As from roots to shoots of rice seedlings.…”