Nitrogen, Phosphorus and Water Contents During Grain Development and Maturation in Wheat

1977 ◽  
Vol 4 (5) ◽  
pp. 799 ◽  
Author(s):  
I Sofield ◽  
IF Wardlaw ◽  
LT Evans ◽  
SY Zee

Plants of five cultivars of wheat were grown under controlled-environmental conditions in order to analyse the effect of cultivar and of temperature and illuminance after anthesis on the accumulation of nitrogen and phosphorus by grains in relation to dry matter. The water relations of the grain during maturation were also examined, using calcium content as an index of water entry. The nitrogen and phosphorus contents of grains increased linearly throughout the grain growth period. The percentage of nitrogen and phosphorus in grains fell sharply during the first few days after anthesis but rose progressively thereafter. The higher the temperature, and the lower the illuminance, the higher was the percentage of nitrogen in the grain of all cultivars. Such conditions also reduce final grain size, but their effects on nitrogen concentration in the grain were apparent early in grain development. No evidence was found of a flush of nitrogen or phosphorus into the grain late in its development. Water entry into the grain continued at a steady rate until maximum grain dry weight was reached, then ceased suddenly. No evidence was found of an increased rate of water loss by the grain at that stage, and the rapid fall in water content at the cessation of grain growth may have been due to blockage of the chalazal zone of entry into the grain by the deposition of lipids. Accumulation of dry matter, nitrogen and phosphorus and entry of water into the grain all ceased at the time of lipid deposition in the chalazal zone.

Bragantia ◽  
2012 ◽  
Vol 71 (3) ◽  
pp. 394-399 ◽  
Author(s):  
Djeimi Isabel Janisch ◽  
Jerônimo Luiz Andriolo ◽  
Vinícius Toso ◽  
Kamila Gabriele Ferreira dos Santos ◽  
Jéssica Maronez de Souza

The objective of this research was to determine growth and dry matter partitioning among organs of strawberry stock plants under five Nitrogen concentrations in the nutrient solution and its effects on emission and growth of runner tips. The experiment was carried out under greenhouse conditions, from September 2010 to March 2011, in a soilless system with Oso Grande and Camino Real cultivars. Nitrogen concentrations of 5.12, 7.6, 10.12 (control), 12.62 and 15.12 mmol L-1 in the nutrient solution were studied in a 5x2 factorial randomised experimental design. All runner tips bearing at least one expanded leaf (patent requested) were collected weekly and counted during the growth period. The number of leaves, dry matter (DM) of leaves, crown and root, specific leaf area and leaf area index (LAI) was determined at the final harvest. Increasing N concentration in the nutrient solution from 5.12 to 15.12 mmol L-1 reduces growth of crown, roots and LAI of strawberry stock plants but did not affect emission and growth of runner tips. It was concluded that for the commercial production of plug plants the optimal nitrogen concentration in the nutrient solution should be 5.12 mmol L-1.


1979 ◽  
Vol 6 (4) ◽  
pp. 449 ◽  
Author(s):  
GR Donovan

Eight wheat varieties which normally produce grain of different final percentage nitrogen content were grown under field and glasshouse conditions. The final percentage grain nitrogen of the field grown varieties ranked in the expected order; however, total nitrogen/grain, DNAIgrain, RNA/grain and non-protein nitrogen/grain during grain development differed between varieties. DNA/grain reached a maximum value in all varieties between 21 and 28 days post- anthesis, suggesting a longer period of cell division than previously reported. There was no apparent relationship between final percentage grain nitrogen and either DNA, total grain RNA or the concentration of grain amino acids during development. Heads from glasshouse grown wheat were detached at 8 days postanthesis and grown in liquid culture under conditions where the nitrogen concentration of the culture medium was varied. Fresh weight/grain, DNA/grain, RNA/grain and total grain nitrogen all increased with increasing nitrogen concentration in the culture medium, but grain dry weight remained constant at the different nitrogen concentrations. The changes in fresh weight/grain, DNA/grain and RNA/grain were not the same for all varieties. A possible relationship between total grain nitrogen and DNA/grain and RNA/grain during seed development exists for heads grown in culture for individual varieties. This apparent relationship for individual varieties cannot be used to explain intervarietal differences in total grain nitrogen because in some cases different varieties grown under identical culture conditions, although producing grain of equivalent total nitrogen, had widely differing levels of both DNA and RNA per grain.


1979 ◽  
Vol 6 (2) ◽  
pp. 187 ◽  
Author(s):  
JHM Thornley

A model of the wheat plant is described which consists of two components, the grain and storage material. Photosynthesis supplies further substrate to the store, from which material is used for grain growth at a rate that depends on the substrate level. The model allows predictions of grain dry weight at maturity and its dependence on total post-anthesis dry matter production, and leads to an interpretation of the source-sink interactions in this situation.


1965 ◽  
Vol 16 (3) ◽  
pp. 265 ◽  
Author(s):  
D Aspinall

The influence of water stress on grain growth has been investigated under conditions of intermittent stress with pot-grown plants and under longer periods of stress with plants grown in lysimeters. Premature cessation of growth was induced by even a moderate water stress, but the rate of grain growth (in dry weight) in the early stages of development was reduced only by severe water stress. There was evidence for an actual loss of dry matter in the final stages of maturation where plants were subjected to severe water stress. Grain moisture content was relatively unaffected by water stress during the major period of grain development, although grain water content dropped with increasing water stress during ripening. Spikelet chlorophyll content was also reduced by water stress, particularly in the later stages of grain development. Indirect evidence indicated that translocation of assimilate from the leaves to the ear was reduced by a moderate water stress. Tne significance of these findings in elucidating the mechanism of action of water stress on grain growth is discussed.


1984 ◽  
Vol 102 (2) ◽  
pp. 371-382 ◽  
Author(s):  
A. H. Weir ◽  
P. L. Bragg ◽  
J. R. Porter ◽  
J. H. Rayner

SummaryA whole crop computer simulation model of winter wheat has been written in FORTRAN and used to simulate the growth of September- and October-sown crops of Hustler wheat at Rothamsted for the years 1978–9, 1979–80 and 1980–1. Results of the simulations, which are for crops with adequate water and nutrients, are compared with observations from experiments at Rothamsted. The model uses daily maximum and minimum temperatures and daylength to calculate the dates of emergence, double ridge, anthesis and maturity of the crops and the growth and senescence of tillers and leaves. In the simulations, the canopy intercepts daily radiation and produces dry matter that is partitioned between roots, shoots, leaves, ears and grain. Partial simulations, using observed LAI values, produced dry matter in close agreement with observations of late-sown crops, but consistently overestimated the total dry-matter production of the early-sown crops. Full simulation described satisfactorily the average difference in dry-matter production to be expected with changes in time of sowing, but did not give as close correspondence for individual crops. A grain growth submodel, that linked maximum grain weight to average temperatures during the grain growth period, correctly simulated the observed growth of individual grains in the 1981 crop. The benefits to be obtained by combining whole crop modelling with detailed crop observations are discussed.


2021 ◽  
Vol 306 ◽  
pp. 04004
Author(s):  
Erliana Novitasari ◽  
Geoffrey P. Savage

Green vegetables are very beneficial for health, but sometimes it is not understood that some vegetables also contain anti-nutrients. For example, oxalic acid can be found in some green vegetables, such as spinach. Oxalic acid can be absorbed from food and as it is a toxin it has to be removed from the body via the kidneys. Under certain conditions, oxalate can combine with calcium in the kidneys forming stones which can lead to impaired kidney function. This study aims to compare two techniques for making vegetable juice, using a high-speed blender or a masticating juicer. The content of oxalic acid, calcium, pH and titratable acidity (TA) was measured in both juices. Total oxalic acid was measured using HPLC, calcium content was analyzed using a Coupled Plasma Optical Emission Spectrophotometer. Dry matter, pH and TA were measured based on AOAC methods. The highest total oxalate (OA) was found in juice made using a masticating juicer of 7638.27 mg OA/100 g dry weight. The highest calcium content was found in the fiber fraction or in the remaining juice using the masticating juicer technique, which was 10.04 mg/100 g juice. Meanwhile, the TA value of the thick juice produced by the high speed blender was not significantly different from the runny juice produced by the masticating juicer. The smoothie-like green juice prepared using a high-speed blender was healthier as the soluble and insoluble oxalate extracted in the juice was lower than in the clear juice prepared using a masticating juicer.


HortScience ◽  
2006 ◽  
Vol 41 (4) ◽  
pp. 1055B-1055
Author(s):  
Gladis Zinati

Plugs of Leucanthemum × superbum `Becky' (Chrysanthemum `Becky', shasta daisy) were grown in #2 containers using pine bark–peat–sand or vermiculite–peat–sand (40:40:20 by volume). Containers were top dressed with either Osmocote Plus 15N–3.9P–9.9K (15–9–12) or Nutricote Plus (18N–2.6P–6.6K (18–6–8) at five rates (0, 0.5×, 1.0×, 1.5×, and 2.0×) to supply 3.9 g N per container at the recommended level (1.0×). Plants were irrigated twice a week using a cyclic irrigation regime consisting of two irrigation applications. Leachates from these containers were collected and evaluated for nitrate and orthophosphate concentrations. Irrespective of the substrate media, Osmocote Plus exhibited a higher rate of nitrogen release at the beginning of the season than Nutricote Plus. Nitrate nitrogen concentration was at least 2.5 times higher in leachates collected from media amended with Osmocote Plus than those with Nutricote Plus. Higher levels of nitrate were found in leachates collected from vermiculite-based media when compared to those from bark-based ones. Phosphate levels in leachates increased as rate of fertilizer increased and were higher in vermiculite-based media than those collected from bark-based media. Plants fertilized with Osmocote Plus were 1.7-fold greater in dry weight than plants fertilized with Nutricote Plus and were 1.2 times greater in vermiculite-based media than those in bark-based media.


1984 ◽  
Vol 35 (5) ◽  
pp. 685 ◽  
Author(s):  
IF Wardlaw ◽  
RL Dunstone

Growth of the capsule and seed of jojoba were followed from pollination to maturity at eight temperature regimens ranging from 15/10 to 36/31�C (8/16 h; photoperiod 16 h). There was an initial lag before the onset of rapid (linear) seed development, during which the capsule expanded, and this lag varied from 106 days at 15/10�C to 7 days at 36/31�C. The wax concentration in the seed was low during the initial stages of development, but reached a maximum when the seeds were 70-75% of their final dry weight. The maximum rate of dry matter accumulation in the seed increased with temperature up to 33/28�C but, because of the longer growth period at low temperature, seed size at maturity was greatest at 18/13�C. The current work suggests that prolonged periods with temperatures above 36/31�C, or below 15/10�C would be harmful to the development of jojoba seed. The high optimum temperature for growth rate of the seed (33/28�C) and sensitivity to a temperature of 15/10�C, puts jojoba into the same group as many subtropical species. However, the lower optimum temperature for seed weight at maturity (18/13�C) is close to that observed for the temperate cereals.


1983 ◽  
Vol 101 (3) ◽  
pp. 741-748 ◽  
Author(s):  
R. A. Leigh ◽  
A. E. Johnston

SUMMARYThe effects of N, P, K and Na silicate fertilizers, and drought on the concentrations of K in the dry matter and tissue water of field-grown spring barley crops have been investigated. Percentage K in dry matter depended on the amounts of N, P, K or water received by the crops and was linearly related to fresh weight to dry weight ratio, but the slope of this relationship depended on whether or not the crops received K. Expressing K concentrations on the basis of tissue water eliminated differences between crops, except for those given insufficient K. Barley crops given fertilizer K maintained K concentrations in their tissue water of about 200 mmol/kg tissue water for most of the growth period but crops grown without K had only 50–70 mmol/kg tissue water. The results indicate that K concentrations in the tissue water are a more reliable indicator of tissue K status than % K in dry matter.Decreases in crop K content resulting from poor K supply were balanced by increases in Na and Ca (but not Mg) contents so that total cation concentrations in the tissue water were similar in low and high K crops. The extra Na and Ca are probably primarily involved in maintaining charge balance for anion absorption but once in the plant they may also substitute for K in its osmotic role.


1970 ◽  
Vol 74 (3) ◽  
pp. 523-531 ◽  
Author(s):  
P. R. Goldsworthy

SUMMARYThe dry weight contributed to the grain yield of sorghum by different parts of the plant was measured by removing laminae and by shading the head. A Nigerian tall variety formed more dry weight after heading and had a larger leaf area duration than a short-season, hybrid sorghum, but its grain yield was smaller. Laminae contributed more than 80% of the dry weight formed after heading in the Nigerian sorghum but less than half of this went into the grain. The remainder went into the stem, mainly to replace respiratory losses, or accumulated in the rachis and branches of the head. Top, middle and bottom groups of laminae contributed 42, 22 and 12% respectively to the dry weight of the grain; the remaining 24% was contributed by the sheaths. In the short-season hybrid sorghum over 70% of the dry matter formed after heading was stored in the grain. Only about half of this came from the laminae; assimilation in the head and in the sheaths contributed about equally to the remainder.


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