Nutrient relations of winter wheat: 1. Accumulation and distribution of Na, K, Ca, Mg, P, S and N

Abstract

SUMMARYMaris Huntsman winter wheat was sown on 30 October 1974 and grown under typical farming conditions. Between sowing and harvest (5 August 1975), the crop was sampled on 23 occasions and dried samples of individual plant components were analysed for Na, K, Ca, Mg, P, S and N composition.The concentration of nutrients within the whole plant generally decreased throughout growth but different parts of the plant varied in their behaviour. Uptake of all nutrients ceased at, or shortly after, anthesis in mid-June while dry-matter accumulation continued slowly for a further 2–3 weeks and almost stopped 4 weeks before harvest. The major period of nutrient uptake occurred between mid-April and mid June coincident with the period of rapid shoot growth. Large amounts of potassium and sulphur (almost 50% of the plant's anthesis content) and lesser amounts of calcium (15%) were lost from the plant after anthesis and efflux from the roots into the soil appeared to be the most likely pathway of removal.Accumulation of nutrients in the ear occurred throughout grain-filling by translocation from other parts of the plant, particularly the leaves and stems: the effects of this redistribution on the production of dry matter after anthesis are discussed.

Concentration, accumulation and uptake rate of macro-nutrients by winter wheat under irrigation

“…An increase in concentration during the early growth stages, as in the case of K, has not previously been widely reported, probably on account of samples not having been analysed regularly during early growth. Nevertheless, Gasser & Thorburn (1972) and Gregory et al (1979) did report increases in concentration of some nutrients during early wheat growth. The decrease in concentration of nutrients lin wheat during later growth stages is well known.…”

“…The decrease in concentration of nutrients lin wheat during later growth stages is well known. According to Gregory et al (1979) the decline in nutrient concentration with age is due to a slower rate of nutrient assimilation relative to carbon. At booting stage, about 70 days after planting, the average concentration of the six nutrients in the whole plant comfortably exceeded the critical values of Melsted, Motto & Peck 1969) and Jones (1986), below which retardation of growth may occur as shown in Table 2.…”

“…Fitted polynomials were used to obtain the average seasonal McGowan (1979) after anthesis, results from the redistribution of nutrients within the plant instead of from further uptake from the soil (Gregory et al, 1979). The amounts of N, P, K, Ca, Mg and S that accumulllted in the grain only are shown in Table 3.…”

“…The work of Gregory et al (1979) and Karlen & Whitney (1980) are to our knowledge the most comprehensive studies of this nature.…”

Growth and yield responses in wheat and barley to potassium supply under drought or moderately saline conditions in the south-west of Western Australia

“…The majority of K uptake in wheat occurs when the shoot is undergoing its rapid phase of growth (Gregory et al 1979), and maximum K accumulation in the shoot is reached at anthesis (Ma et al 2013). The occurrence of K uptake mostly during the vegetative growth and substantial K redistribution at the reproductive stage in wheat suggests the benefit of early K fertilisation.…”