Agronomic selenium biofortification of two-rowed barley under Mediterranean conditions

Abstract

In order to improve the nutritional value of two-rowed barley grain, two foliar selenium (Se) fertilizers (sodium selenate and sodium selenite) at four rates (0-10-20-40 g/ha) were applied during the growing seasons 2010/2011 and 2011/2012 in a field experiment conducted under semiarid Mediterranean conditions. The grain harvested in the 2010/2011 season accumulated a greater amount of total Se than the grain of the 2011/2012 season. Sodium selenate was much more effectively taken by plants than sodium selenite, and there was a strong and linear relationship between total Se concentration and Se rate in both sodium selenate and selenite. For each gram of Se fertilization, applied as sodium selenate or sodium selenite, the increases of total Se concentration in grain were 44 and 9 μg/kg dry weight, respectively. No increments in total or available Se were observed in soil after harvesting even at the highest doses of either fertilizer. It can be concluded that two-rowed barley would be a good candidate to be included in biofortification programs under Mediterranean conditions to increase Se in animal feeding and in the human diet through beer production.