Essential and toxic elements accumulation in genetically variable rice (Oryza sativa L.) varieties from Sri Lanka

Essential minerals are crucial for maintaining physicochemical processes and are important as chemical components in many metabolic processes in the human body. However, higher rates of mineral malnutrition are observed among the populations consuming rice. On the other hand, the uptake of toxic elements in rice grains is high, causing serious health issues among consumers. Due to the widespread prevalence of chronic diseases, greater attention is paid to rice quality. Since the accumulation of trace elements in rice grains might depend on the genotype, this study identified nutrient-rich rice varieties with a lower potential for accumulation of toxic elements. A poly-tunnel experiment was conducted under controlled soil and environmental conditions with ten different rice varieties, including native and improved varieties. Element contents in rice grains and husks were analyzed using an inductively coupled plasma spectrometer (ICP-MS). When considering the essential micro-elements, the Indigenous variety Beheth-heenati had the highest Fe, Zn, Mn, Cu, Mo and V enrichment in rice grains. Lower accumulation of As and Cd was observed in Kahawanu, Bg-300 and Madathawalu. Grains and husks showed comparatively similar distribution patterns or, in some cases, higher accumulation in rice husks. Identifying genotypes with higher intake of essential element uptakes and lower accumulation of toxic elements is crucial for developing new rice varieties. The identified genotypes can be used in breeding programs to transfer these desired varieties into high-yielding rice rich in nutrients and low in toxic elements.