Table I. Results of linear combination fitting of Se K_α edge XANES data for cowpea roots exposed to either 20 µm Se[VI] or Se[IV] for 24 h.

Sample	Standard					R Factora
	SeO42−	SeO32−	SeMet	SeCys	Methylselenocysteine
			%
Exposed to Se[VI]	74 ± 0.6	–	26 ± 0.6	–	–	0.0019
Exposed to Se[IV]	–	–	71 ± 1.2	29 ± 1.1	–	0.0001

^aR factor = Σ_i(experimental fit)²/Σ_i(experimental)², where the sums are over the data points in the fitting region.