AbstractIn 1992 and 1993, respectively, 400 and 393 wheat grain samples were collected representatively from the major wheat‐growing areas in Britain. Concentrations of S in the grain and the N: S ratios were determined, and the variations due to variety and geographical distribution were analysed. Grain S concentration ranged from 0.54 to 2.09, with a mean of 1.43 mg g−1in 1992, and from 0.80 to 1.67, with a mean of 1.26 mg g−1: in 1993. The ranges of grain N: S ratio were 13.3‐29.6, with a mean of 15.8 in 1992, and 11.5‐25.9, mean 15.6 in 1993. Breadmaking varieties contained significantly greater N and S concentrations in the grain than other varieties, but only small differences were found in the N: S ratio in grain. In 1992 and 1993, 7 and 26 of the samples had a S concentration below the critical value of 1.2 mg g−1, respectively, whereas 10 and 7 of the samples had an N: S ratio greater than the critical value of 17. In both years 2.5 of the samples satisfied both criteria of S deficiency. Comparison of the results of 1992–1993 with those of 1981–1982 (Byerset al. J Sci Food Agric38(1987) 151–160) showed a significant decrease in the S status of British wheat grain during the 10–12 year period. The decrease can be attributed mainly to decreased S inputs, particularly from atmospheric deposition. The pattern of geographical distribution of grain S concentrations was not as strong as it was in the 1982 survey. However, it was still apparent that grain samples with small S concentrations were located mainly in Scotland, northern England, and the west and southwest of England, whereas the largest S concentrations occurred mainly in the areas near to or down‐wind of the industrial conurbatio
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