The role of the leaves in the accumulation of nitrogen by wheat during ear development

1963 ◽  
Vol 14 (6) ◽  
pp. 725 ◽  
Author(s):  
TF Neales ◽  
MJ Anderson ◽  
IF Wardlaw

When wheat plants were deprived of nitrogen in the rooting medium at anthesis there was a small, but significant, increase in the nitrogen content of the grain at maturity. It was shown that there was a greater migration of nitrogen from the leaves and stem to the ear in plants deprived of nitrogen than in those plants supplied with nitrogen throughout ear development. In an examination of the effects on grain nitrogen content of leaf removal at anthesis, it was shown that this treatment reduces the uptake of nitrogen into the culm and the nitrogen content of the grain at maturity. Ear shading treatments significantly reduced the total nitrogen content of the grain in one experiment. Ear shading also decreased the amino nitrogen, and increased the nitrate nitrogen, content of the ear. Variation of the grain dry weight per ear, induced by shading, by defoliation treatments, or by differences in variety, were positively correlated with grain nitrogen content. Either the movement of dry matter and nitrogen into the ear are interdependent, or they are both promoted by some external factor, such as rate of growth of the ear. The possible importance of the leaves of the wheat plant in promoting the uptake of nitrogen into the culm and in supplying nitrogen to the grain is discussed.

1965 ◽  
Vol 16 (6) ◽  
pp. 893 ◽  
Author(s):  
IF Wardlaw ◽  
DJ Carr ◽  
MJ Anderson

Leaf contribution to grain dry weight and grain nitrogen was estimated in four varieties of wheat from their responses to shading and defoliation treatments. The relation between movement of nitrogen and dry material from leaves to grains appeared as an important factor in the differences between varieties in respect to the percentage nitrogen content of grains. Experiments with labelled carbon, however, showed that there was a significant redistribution of assimilates from other parts when the ear was shaded or the flag leaf removed.


Genetika ◽  
2014 ◽  
Vol 46 (1) ◽  
pp. 27-32
Author(s):  
Desimir Knezevic ◽  
Sonja Maric ◽  
Vlado Kovacevic ◽  
Nevena Djukic ◽  
Srdjan Atanasijevic

In diallel crosses (without reciprocals) of four genetically divergent wheat cultivars (Yugoslavia, Osijecanka, Zitnica, and NS Rana 2) the variability and inheritance of nitrogen content in wheat plant were investigated. The mode of inheritance, gene effect, heritability in parent cultivars and F2 hybrids were studied. The different mode of inheritance: partial dominance, intermediate and overdominance for analyzed trait was established. Among parent cultivars, the highest nitrogen contents had Novosadska Rana 2 (3.52%). The combination Zitnica/NS Rana 2 in F2 grain generation was the best for nitrogen content.


2017 ◽  
Vol 7 (4) ◽  
pp. 30-34 ◽  
Author(s):  
O. A. Didur ◽  
Yu. L. Kulbachko ◽  
V. Y. Gasso

<p>The problem of transformation of natural landscapes resulted from the negative technogenic impact is highlighted. It is shown that mining enterprises are powerful anthropo-technical sources of organic and inorganic toxicants entering the environment. Their wastes pollute all components of the ecosystems and negatively influence human health by increasing a risk of disease. The nature of the accumulation of trace elements (Fe, Cu, Zn, Ni, Cd, and Pb) by invertebrate animals of various functional groups under conditions of anthropo-technogenic pressure was studied. The sample plots were located on self-overgrowing sites with ruderal vegetation located in the immediate vicinity of the Mangan ore-dressing and processing enterprise (Dnipropetrovsk region). It is quite naturally that among the studied biogenic microelements (Fe, Cu, Zn and Ni), the phyto-, zoo-, and saprophages in the investigated zone of technogenic pollution most actively accumulate Fe:<em> </em>22758, 17516 and 18884 mg/kg dry weight on average, respectively. There are significant differences (p ≤ 0.05) in the content of studied microelements between saprophages and phytophages. The saprophages accumulate such trace metals as Mn, Cu, Zn and Cd in high quantities, but Ni and Pb – in smaller ones. The saprophagous functional group of invertebrates is an active agent of detritogenesis, in the conditions of modern nature management it acts as a powerful element of ecosystem engineering (habitat transformation), the main ecological role of which is to modify the habitat of other soil biota. In addition, the saprophages fulfil their concentrating geochemical function. They actively participate in the most important soil biochemical process: the formation of humus, the migration of microelements along trophic chains, the biological cycle in general, and provide such supporting ecosystem services as increasing soil fertility and nutrient cycling.</p>


2020 ◽  
Vol 74 (4) ◽  
pp. 493-513
Author(s):  
Holmer Steinfath

Time is a neglected subject in recent, especially analytically minded reflections on the good life. The article highlights the fundamental role of time and temporality for an adequate understanding of the good life. Time functions both as an external factor with which we have to reckon in our practical deliberations and as an internal structure of living our lives. It is argued that striving for a good life also means striving for being in harmony with the time of one's life. The exploration of this idea allows to link analytical with phenomenological approaches to time and good life.


2020 ◽  
Vol 2 (6) ◽  
pp. 147-158
Author(s):  
L. N. KRASAVINA ◽  
◽  
L. I. KHOMYAKOVA ◽  

The article discusses the features of the functioning of national payment systems of the countries of the Shanghai Cooperation Organization (SCO). The specifics of the payment systems of the SCO countries are revealed, the emphasis is placed on their regional features. The role of central banks in ensuring the stable and safe functioning of national payment systems is highlighted. The importance of the supervisory function of central banks in order to control the payment system operators of the SCO countries is emphasized. Forecasts of the development of remote and digital technologies in the payment sector are given taking into account the influence of a new external factor (pandemic).


2021 ◽  
Vol 13 (9) ◽  
pp. 5074
Author(s):  
Urooj Kanwal ◽  
Muhammad Ibrahim ◽  
Farhat Abbas ◽  
Muhammad Yamin ◽  
Fariha Jabeen ◽  
...  

Phytoremediation is a cost-effective and environmentally friendly approach that can be used for the remediation of metals in polluted soil. This study used a hedge plant–calico (Alternanthera bettzickiana (Regel) G. Nicholson) to determine the role of citric acid in lead (Pb) phytoremediation by exposing it to different concentrations of Pb (0, 200, 500, and 1000 mg kg−1) as well as in a combination with citric acid concentration (0, 250, 500 µM). The analysis of variance was applied on results for significant effects of the independent variables on the dependent variables using SPSS (ver10). According to the results, maximum Pb concentration was measured in the upper parts of the plant. An increase in dry weight biomass, plant growth parameters, and photosynthetic contents was observed with the increase of Pb application (200 mg kg−1) in soil while a reduced growth was experienced at higher Pb concentration (1000 mg kg−1). The antioxidant enzymatic activities like superoxide dismutase (SOD) and peroxidase (POD) were enhanced under lower Pb concentration (200, 500 mg kg−1), whereas the reduction occurred at greater metal concentration Pb (1000 mg kg−1). There was a usual reduction in electrolyte leakage (EL) at lower Pb concentration (200, 500 mg kg−1), whereas EL increased at maximum Pb concentration (1000 mg kg−1). We concluded that this hedge plant, A. Bettzickiana, has the greater ability to remediate polluted soils aided with citric acid application.


2020 ◽  
Vol 38 (3) ◽  
pp. 273-286 ◽  
Author(s):  
Cristina Garcia-Cabezon ◽  
Celia Garcia-Hernandez ◽  
Maria L. Rodriguez-Mendez ◽  
Gemma Herranz ◽  
Fernando Martin-Pedrosa

AbstractMicrostructural changes that result in relevant improvements in mechanical properties and electrochemical behavior can be induced using different sintering conditions of ASTM F75 cobalt alloys during their processing using powder metallurgy technique. It has been observed that the increase in carbon and nitrogen content improves corrosion resistance and mechanical properties as long as the precipitation of carbides and nitrides is avoided, thanks to the use of rapid cooling in water after the sintering stage. In addition, the reduction of the particle size of the powder improves hardness and resistance to corrosion in both acid medium with chlorides and phosphate-buffered medium that simulates the physiological conditions for its use as a biomaterial. These results lead to increased knowledge of the role of carbon and nitrogen content in the behavior displayed by the different alloys studied.


Plants ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 788
Author(s):  
Shaban R. M. Sayed ◽  
Shaimaa A. M. Abdelmohsen ◽  
Hani M. A. Abdelzaher ◽  
Mohammed A. Elnaghy ◽  
Ashraf A. Mostafa ◽  
...  

The role of Pythium oligandrum as a biocontrol agent against Pythium aphanidermatum was investigated to avoid the harmful impacts of fungicides. Three isolates of P. oligandrum (MS15, MS19, and MS31) were assessed facing the plant pathogenic P. aphanidermatum the causal agent of Glycine max damping-off. The tested Pythium species were recognized according to their cultural and microscopic characterizations. The identification was confirmed through sequencing of rDNA-ITS regions including the 5.8 S rDNA. The biocontrol agent, P. oligandrum, isolates decreased the mycelial growth of the pathogenic P. aphanidermatum with 71.3%, 67.1%, and 68.7% through mycoparasitism on CMA plates. While the half-strength millipore sterilized filtrates of P. oligandrum isolates degrade the pathogenic mycelial linear growth by 34.1%, 32.5%, and 31.7%, and reduce the mycelial dry weight of the pathogenic P. aphanidermatum by 40.1%, 37.4%, and 36.8%, respectively. Scanning electron microscopy (SEM) of the most effective antagonistic P. oligandrum isolate (MS15) interaction showed coiling, haustorial parts of P. oligandrum to P. aphanidermatum hyphae. Furthermore, P. oligandrum isolates were proven to enhance the germination of Glycine max seedling to 93.3% in damping-off infection using agar pots and promote germination of up to 80% during soil pot assay. On the other hand, P. oligandrum isolates increase the shoot, root lengths, and the number of lateral roots.


1998 ◽  
Vol 279 (5) ◽  
pp. 1123-1136 ◽  
Author(s):  
Ben Luisi ◽  
Modesto Orozco ◽  
Jiri Sponer ◽  
Francisco J Luque ◽  
Zippora Shakked

2014 ◽  
Vol 1081 ◽  
pp. 110-114 ◽  
Author(s):  
Zhen Zhu ◽  
Hua Yin ◽  
Yan An

This research adopts the pancreatin hydrolysis of silk fibroin active peptide, evaluate the antioxidant activity of hydrolysates. In the process of hydrolysis of silk fibroin, by measuring the amino nitrogen content of neutral formaldehyde titration method. Find the amino nitrogen content gradually stabilized at around 0.37g/L, and superoxide free radical scavenging rate changing with time fluctuation trend, superoxide free radical scavenging rate to a maximum of 65.03% at 220min.The use of silk fibroin hydrolysis process optimization,reaction time 160min, enzyme concentration4% , substrate concentration 20mg/ml, pH 8, temperature 38°C. The hydrolysis process under the hydrolysate on superoxide radical scavenging rate of 72.73%. The scavenging rate of hydroxyl radical is 47.24%. Red blood cell hemolysis induced by H2O2 inhibition rate was 24.30%.


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