Effects of nitrogen and sulphur fertilisers on the yield, N and S content, and amino acid composition of the grain of spring wheat

Abstract

Spring wheat (cv. Kleiber) was grown in three pot experiments in a soil containing 10 mg kg-1 KH~P04-soluble sulphur with different rates of nitrogen and sulphur fertilisers. Without added S the yields of grain dry matter and crude protein were either unchanged (glasshouse experiment) or significantly decreased by the N treatments (controlled environment experiments). With added S the N fertiliser increased the yields by 4&110%. The experiments produced grain with a wide range of N and S contents, the latter ranging from 0.06-0.21 % on a dry matter basis. Grain from treatments giving the largest yields of dry matter and crude protein had a N: S ratio of about 15. The amino acid composition of the whole grain was changed significantly by the fertiliser treatments. When plants were grown without added S at the highest level of N the grain contained less than half the amount of cyst(e)ine and methionine (as % of total amino acid content) found in grain from plants given adequate amounts of S fertiliser. Grain from S-deficient plants also had a much greater content of aspartic acid + asparagine but less threonine, leucine, isoleucine and lysine. The N: S ratio in grain from plants grown with insufficient S was well in excess of 15. The relation of these findings to the nutritive value of wheat as a feed and to the provision of enough disulphide bonding capacity for its use in bread-making are discussed. Our results emphasise the necessity for having an adequate amount of S to balance the larger N applications now given to wheat to ensure that the grain is of the highest quality possible with any particular cultivar.

Sulfur and nitrogen fertilizer effects on wheat. I. Concentrations of sulfur and nitrogen and the nitrogen to sulfur ratio in grain, in relation to the yield response

“…Sulfur application has been reported to decrease (Byers and Bolton 1979) or increase (Archer 1974) grain nitrogen. The present experiments, over a wider range of sulfur supply levels, have shown (Tables 2 and 3) that an increment of applied sulfur may increase or decrease grain nitrogen or have no effect, depending on the sulfur status and the nitrogen supply.…”

“…The wide (N/S), ratios of sulfur-sufficient samples represented in area B could be due to high nitrogen supply especially during grain filling or to an accumulation of nitrogen due to a limitation on yield by some other factor. Data from Archer (1974) and Byers and Bolton (1979) are also plotted. These represent a range of cultivars and culture conditions but embrace a limited number of sulfur treatments.…”

Importance and Effect of Nitrogen on Crop Quality and Health

“…The balance between nitrogen and sulfur nutrition of the wheat crop also had an effect on grain amino acid composition. Byers and Bolton (1979) and Wrigley et al (1980) observed that high levels of nitrogen supply and marginal levels of sulfur supply resulted in marked reductions of the concentration of cysteine and methionine. Timms et al (1981) observed the similar reductions caused by a nitrogento-sulfur imbalance induced by late-season fertilization of wheat with urea.…”

Effect of Sulphur Fertilization on Grain Quality and Protein Composition of Durum Wheat (Triticum durum Desf.)

“…An environmental policy leading to reduce SO 2 atmospheric emissions, the massive use of nitrogen and phosphorus fertilizers and the introduction of high yielding crop cultivars resulted in a decrease in the sulphur content in the soils. Several researches agree on the importance of sulphur as a limiting factor in wheat production and quality deterioration (Byers and Bolton, 1979; Effect of Sulphur Fertilization on Grain Quality and Protein Composition of Durum Wheat (Triticum durum Desf.) Wrigley et al, 1984;Castle and Randall, 1987;MacRitchie and Gupta, 1993;Zhao et al, 1999aZhao et al, , 1999bLuo et al, 2000;Wooding et al, 2000aWooding et al, , 2000bWieser et al, 2004;Lerner et al, 2006).…”