Selenium concentrations in UK wheat and biofortification strategies

main reason for the generally low Se status in UK wheat is a lowSe supply from soil. Other soil factors such as pH, organic

variation in mineral composition within plant orders and species.

d Phmatter content and the availability of sulphate also have a majorinfluence on selenium uptake by plants. Because cereals are animportant source of Se to humans, Se biofortification of wheatwould have a desirable effect on increasing human Se intake.Results from a field trial show that grain Se concentration wasincreased by 327 fold by additions of 1020 g Se/ha as sodiumselenate at the stem extension stage. Other strategies of Sebiofortification, such as genetic improvement to enhance Seaccumulation potential, should also be explored.

doi:10.1016/j.cbpa.2007.01.571

P4.102006 Plos Genetics 2(12): e210.). By varying the concentrationsof multiple nutrients in the soil, we have observed severalunexpected alterations in the ionome, including significantdifferences in the accumulation of macro- and micronutrients inresponse to changing soil iron levels. In a complementary reversegenetic approach we have also characterized over 1000 uniquesequenced T-DNA insertional alleles for genes that affect theshoot ionome. To maximize the value of this ionomics approach,we have developed a publicly searchable online databasecontaining ionomic information on over 60,000 plants (www.purdue.edu/dp/ionomics; Baxter et al., 2007 Plant Physiol 143(2)in press), and the database is being updated regularly.

doi:10.1016/j.cbpa.2007.01.570

P4.9Selenium concentrations in UK wheat and biofortificationstrategies

F. Zhao, S. McGrath, C. Gray, J. Lopez-Bellido, (Rothamsted)

Selenium is essential for humans and animals but has noknown function in plants. Dietary intake of selenium is low in alarge number of people worldwide. In some European countries,dietary Se intakes have decreased significantly in recentdecades. For example, average Se intake of UK adults hasdecreased by more than 40% from the mid 1970s to 1995. Themain reason for this trend is the decreased importation of bread-making wheat from North America, which generally containsmuch more Se than European wheat. Our survey of 452 grainsamples of bread-making wheat produced in the UK shows arange of 6858 g Se/kg dry weight with a mean and median of32 and 22 g Se/kg, respectively. Furthermore, 91% of thesamples contained