Effect of sulphur deficiency on the growth and metabolism of sugar beet (Beta vulgaris cv Druid)

Sugar beet plants were grown in variations of a nutrient culture system to induce sulphur deficiency. The effect of sulphur deprivation on the growth and metabolism was investigated by measuring leaf area, chlorophyll content , fresh and dry weights, sulphur, nitrogen, sulphate and nitrate concentrat ions, glutathione and free amino acid concentrations. Both total sulphur an d sulphate concentrations were markedly reduced in response to sulphur defi ciency, while significant increases in arginine concentration in shoot tiss ue were observed. Increases were also observed in shoot nitrogen and nitrat e concentrations and both shoot and root N/S ratios. These results demonstr ate that total sulphur, sulphate S and sulphate as a percentage of total S are suitable indicators of sulphur deficiency in sugar beet. Arginine respo nds to sulphur deficiency, but its use as an indicator needs validation und er field conditions. (C) 2000 Society of Chemical Industry.