Impact of sulphur fertilisation on crop response to selenium fertilisation

• Published in: Plant and soil 2010-07, Vol.332 (1-2), p.31-40
• Main Authors: Stroud, J. L, Li, H. F, Lopez-Bellido, F. J, Broadley, M. R, Foot, I, Fairweather-Tait, S. J, Hart, D. J, Hurst, R, Knott, P, Mowat, H, Norman, K, Scott, P, Tucker, M, White, P. J, McGrath, S. P, Zhao, F. J
• Format: Article
• Language: English
• Subjects: Agricultural site preparation; Agricultural soils; Agrology; Agronomy; Agronomy. Soil science and plant productions; Animal, plant and microbial ecology; Biological and medical sciences; Biomedical and Life Sciences; Crop yield; Ecology; Fertilizers; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; Grain; Grains; Life Sciences; Plant Physiology; Plant Sciences; Plants; Regular Article; Selenium; Selenium biofortification; Selenium speciation; Soil science; Soil Science & Conservation; Soil-plant relationships. Soil fertility; Soil-plant relationships. Soil fertility. Fertilization. Amendments; Straw; Sulfur; Sulfur compounds; Sulphate; Wheat; Wheat soils
• ISSN: 0032-079X; 1573-5036
• DOI: 10.1007/s11104-009-0230-8

UK wheat (Triticum aestivum L.) has a low selenium (Se) concentration and agronomic biofortification with Se is a proposed solution. A possible limitation is that UK wheat is routinely fertilised with sulphur (S), which may affect uptake of Se by the crop. The response of wheat to Se and S fertilisation and residual effects of Se were determined in field trials over 2 consecutive years. Selenium fertilisation at 20 g ha⁻¹ as sodium selenate increased grain Se by four to seven fold, up to 374 µg Se kg⁻¹. Sulphur fertilisation produced contrasting effects in 2 years; in year 1 when the crop was not deficient in S, grain Se concentration was significantly enhanced by S, whereas in year 2 when crop yield responded significantly to S fertilisation, grain Se concentration was decreased significantly in the S-fertilised plots. An incubation experiment showed that addition of sulphate enhanced the recovery of selenate added to soils, probably through a suppression of selenate transformation to other unavailable forms in soils. Our results demonstrate complex interactions between S and Se involving both soil and plant physiological processes; S can enhance Se availability in soil but inhibit selenate uptake by plants. Furthermore, no residual effect of Se fertiliser applied in year 1 was found on the following crop.