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A quantitative procedure was developed for the determination of soil sugars by gas‐liquid chromatography of the acetate derivatives of the alditols obtained by reduction of the sugars. Myoinositol or quebrachitol was used as an internal standard during the production of alditol acetates and their separation by gas‐liquid chromatography.Sugars were isolated from soil hydrolysates by neutralization of the acid and precipitation of the sulfate using strontium carbonate. The filtrates were evaporated to dryness and the sugars extracted using methanol.The release of monosaccharides from soils using H2SO4 was studied and conditions of hydrolysis are recommended which depend on the nature of the soil and the purpose of the investigation.

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Increases in the total grain nitrogen of barley (cv. Julia and Bomi), resulting from increased N fertilisation, are accompanied by decreases in the relative lysine content of the grain proteins. Extraction of the grain proteins shows that the high-N grain have increased relative and total amounts of the lysine-poor storage protein (hordein) fraction. There are only small increases in the total amounts of the other more lysine-rich protein fractions (salt-soluble proteins and glutelint residue proteins).There is also little or no effect on the amino acid compositions of the fractions.Consequently, it is concluded that the decreased relative lysine content of the whole grain is due to the increased synthesis of hordein. Further evidence for this hypothesis comes from similar studies with the high-lysine mutant, Riser 1508, in which the high-lysine character results from a decrease in the relative and total amount of hordein. The hordein fraction does not increase disproportionately with increasing grain N, nor does the relative lysine content of the grain decrease. There is no effect of grain N on the polypeptide compositions of the salt-soluble proteins of either line. However, in Bomi and Julia increased grain N does result in an increase in the relative amount of sulphur-poor 'C' hordein polypeptides in the hordein fraction. I t is speculated that this results from limitation of S relative to N.

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