Determination of Selenium Concentration of Rice in China and Effect of Fertilization of Selenite and Selenate on Selenium Content of Rice

Abstract

A method of hydride generation atomic fluorescence spectrometry was applied to the determination of the selenium concentration of regular polished rice in China and selenium-enriched polished rice obtained by foliar application of selenium-enriched fertilizer in the forms of selenite and selenate. The average selenium content of regular rice was 0.025 +/- 0.011 microg g(-)(1). On the basis of a daily dietary rice intake of 300-500 g suggested by the China Nutrition Society, the total selenium intake from regular rice was calculated to be 7.5-12.5 microg per person per day for an adult. The selenium contents of rice were significantly increased to 0.471-0.640 microg g(-)(1) by foliar application of selenium-enriched fertilizer at rate of 20 g of Se ha(-)(1) in the forms of sodium selenite and sodium selenate. The selenium content of rice by application of a fertilizer of selenate was 35.9% higher than that by a fertilizer of selenite, which showed that Se-enriched fertilizer in selenate exhibited greater efficiency in increasing Se content in rice products. The Se-enriched rice products can increase daily Se intake on average by 100-200 microg of Se per day by the consumption of 400 g of rice products if the Se level of rice products is controlled at 0.3-0.5 microg of Se g(-)(1). Because rice is a staple food in China, selenium-enriched rice obtained by bioenrichment of selenium to increase the Se content of rice could be a good selenium source for the population in selenium-deficient regions.

Distribution and Translocation of Selenium from Soil to Grain and Its Speciation in Paddy Rice (Oryza sativa L.)

“…Se fertilizers have been widely used in some countries, such as Finland to enhance Se concentration in cereals (5,(10)(11)(12). More recently, in order to enhance Se levels in meat and diary products in the UK, commercial Se fertilizers are applied to pasture and forage crops (35).…”

Determining the fate of selenium in wheat biofortification: an isotopically labelled field trial study

“…Despite the wide range of application rates employed in cereal crop Se biofortification studies, from <10 to 500 g ha et al 2010, Chilimba et al 2012aGalinha et al 2012;Wang et al 2013); this is also true of herbage sward studies (Whelan 1989;Rimmer et al 1990;Shand et al 1992;Valle et al 2002). It is also widely accepted that crop uptake of selenate (Se VI ) exceeds that of selenite (Se IV ) (Shand et al 1992;Chen et al 2002;Zhao et al 2005;Galinha et al 2012, Ros et al 2016) mainly because selenate is more soluble in soil within the pH range of arable soils (Fleming 1980;Jacobs 1989;Neal 1995) making it more bioavailable (Zayed et al 1998;Li et al 2008;Stroud et al 2010b). Yläranta (1983) observed that application of just 10-20 g ha −1 Na 2 SeO 4 (Se VI ) was sufficient to produce barley grain Se concentrations of 100-200 μg kg −1 , whereas over 100 g ha…”

Selenium biofortification and antioxidant activity in lettuce plants fed with selenate and selenite

“…Thus, biofortification of agricultural crops with Se, by means of adding Se along with fertilizers, is a useful technique to increase the consumption of Se by animals and man (Chen et al 2002, Ríos et al 2008, White and Broadley 2009, Broadley et al 2010. Inorganic Se forms differ in terms of absorption and mobility within plants; selenate is more easily transported to shoots, while selenite tends to accumulate in plant roots (Zhang et al 2003).…”