scholarly journals Amino acid and ureide transport in the xylem of symbiotic soybean plants during short-term flooding of the root system in the presence of different sources of nitrogen

2006 ◽  
Vol 18 (2) ◽  
pp. 333-339 ◽  
Author(s):  
André Luís Thomas ◽  
Ladaslav Sodek
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
N2 Fixation ◽  
Xylem Sap ◽  
Organic N ◽  
N Source ◽  
Root Hypoxia ◽  
N Metabolism ◽  
Soybean Plants ◽  
Different Sources

The transport of organic N compounds to the shoot in the xylem sap of nodulated soybean plants was investigated in an attempt to better understand the changes in N metabolism under root hypoxia (first 5 days of flooding), with different sources of N in the medium. NO3- is beneficial for tolerance of plants to waterlogging, whereas other N sources such as NH4+ and NH4NO3, are not. Nevertheless, in the presence of NH4+ high levels of amino acids were transported in the xylem, consistent with its assimilation. Some increase in the transport of amino acids was also seen with NO3- nutrition during waterlogging, but not with N-free medium. Ureide transport in the xylem was severely reduced during waterlogging, consistent with impaired N2 fixation under these conditions. The relative proportions of some amino acids in the xylem showed dramatic changes during treatment. Alanine increased tremendously under root hypoxia, especially with NH4+ as N source, where it reached near 70 % of the total amino acids present. Aspartic acid, on the other hand, dropped to very low levels and was inversely related to alanine levels, consistent with this amino acid being the immediate source of N for alanine synthesis. Glutamine levels also fell to a larger or lesser extent, depending on the N source present. The changes in asparagine, one of the prominent amino acids of the xylem sap, were most outstanding in the treatment with NO3-, where they showed a large increase, characteristic of plants switching from dependence on N2 fixation to NO3- assimilation. The data indicate that the lesser effectiveness of NH4+ during waterlogging, in contrast to NO3-, involves restricted amino acids metabolism, and may result from energy metabolism being directed towards NH4+ detoxification.

Root uptake and xylem transport of cadmium in wheat and triticale as affected by exogenous amino acids

2017 ◽  
Vol 68 (5) ◽  
pp. 415 ◽  
Author(s):  
K. Khodamoradi ◽  
A. H. Khoshgoftarmanesh ◽  
S. A. M. Mirmohammady Maibody
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Bread Wheat ◽  
Nutrient Solution ◽  
Metal Ion ◽  
Xylem Sap ◽  
Root Uptake ◽  
Plant Roots ◽  
Control Treatment ◽  
Long Distance

Organic acids exuded from plant roots significantly modify uptake and long-distance translocation of metals. Little is known about the effect of amino acids on metal ion uptake by plant roots. The present study investigated the effects of exogenous amino acids (histidine and glycine) in a nutrient solution on root uptake and xylem sap transport of cadmium (Cd) in triticale (× Triticosecale cv. Elinor) and bread wheat (Triticum aestivum L. cv. Back Cross Rushan). Plant seedlings were grown in a Cd-free modified Hoagland nutrient solution to which 1 µm Cd was added with either 50 µm histidine or 50 µm glycine or without amino acids at 4 weeks after germination. A control treatment consisted of a nutrient solution free of Cd and amino acids. In bread wheat, addition of histidine to the Cd-containing nutrient solution resulted in a higher operationally defined symplastic Cd fraction but a lower apoplastic one in the roots. In triticale, addition of either amino acid decreased the symplastic Cd fraction but increased the apoplastic one. Addition of histidine to the nutrient solution increased Cd concentration in wheat xylem sap but had no significant effect on Cd concentration in triticale xylem sap. Compared with the Cd-only treatment, the glycine-containing treatment led to significantly reduced Cd concentrations in xylem sap of both plant species. Wheat plants supplied with histidine and Cd accumulated greater amounts of Cd in their shoots than those supplied with Cd alone. Glycine had no significant effects on the Cd content of wheat shoots but decreased it in triticale shoots. Results indicate that the effects of amino acids on plant root uptake and xylem sap translocation of Cd depend on the type of amino acid supplemented. This finding is of great importance for selecting and/or breeding cultivars with Cd-toxicity tolerance.

Highly Specialized Nitrogen Metabolism in a Freshwater Phytoplankter, Chrysochromulina breviturrita

1987 ◽  
Vol 44 (4) ◽  
pp. 736-742 ◽  
Author(s):  
John D. Wehr ◽  
Lewis M. Brown ◽  
Kathryn O'Grady
Keyword(s):  
Nitrogen Metabolism ◽  
Laboratory Culture ◽  
Organic N ◽  
Acidic Precipitation ◽  
Inorganic N ◽  
Culture Study ◽  
N Source ◽  
Softwater Lakes ◽  
N Metabolism ◽  
N Compounds

A field and laboratory culture study was carried out on the nitrogen metabolism of isolates of the freshwater phytoplankter Chrysochromulina breviturrita Nich. (Prymnesiophyceae). These were isolated from two different softwater lakes, one believed to be influenced by acidic precipitation (Cinder Lake) and another which was experimentally acidified with H2SO4 (Lake 302-South). The alga was able to utilize only NH4+ as an inorganic N source. A range of irradiances and molybdenum concentrations failed to induce NO3− utilization. Among 17 organic N compounds including amino acids, purines, and other amines, only urea plus Ni2+ as a cofactor would serve as the sole N source for this species. Nonetheless, growth rates in media supplied with urea were significantly less than with NH4+. Field data from Lake 302-S indicate that a predominance of NH4+ versus NO3− as the major inorganic N species may have favored the development of a Chrysochromulina-dominated community during August 1984. A detailed depth profile also indicated that a metalimnetic peak (> 20 × 106 cells/L) of this alga coincided with a distinct NH4+ depletion, which occurred at no other time during the year. Experiments with isolates of C. breviturrita and a Nannochloris sp. (Chlorophyceae) (~ 1 μm in diameter) from this community indicated that the former alga possessed a highly specialized N metabolism much like the Cinder Lake isolate. The Nannochloris sp. from the same environment grew on NO3− and NH4+ equally well. It is suggested that the specialized NH4+ utilization by C. breviturrita may itself influence the pH regime of poorly buffered waters through selective NH4+ uptake and H+ generation.

scholarly journals Interactions between uptake of amino acids and inorganic nitrogen in wheat plants

2011 ◽  
Vol 8 (6) ◽  
pp. 11311-11335 ◽  
Author(s):  
E. Gioseffi ◽  
A. de Neergaard ◽  
J. K. Schjoerring
Keyword(s):  
Amino Acids ◽  
Nutrient Solution ◽  
Inorganic Nitrogen ◽  
N Uptake ◽  
Organic N ◽  
Arable Soils ◽  
Inorganic N ◽  
N Losses ◽  
Total N ◽  
N Source

Abstract. Soil-borne amino acids may constitute a nitrogen (N) source for plants in various terrestrial ecosystems but their importance for total N nutrition is unclear, particularly in nutrient-rich arable soils. One reason for this uncertainty is lack of information on how the absorption of amino acids by plant roots is affected by the simultaneous presence of inorganic N forms. The objective of the present study was to study absorption of glycine (Gly) and glutamine (Gln) by wheat roots and their interactions with nitrate (NO3–) and (NH4+) during uptake. The underlying hypothesis was that amino acids, when present in nutrient solution together with inorganic N, may lead to down-regulation of the inorganic N uptake. Amino acids were enriched with double-labelled 15N and 13C, while NO3– and NH4+ acquisition was determined by their rate of removal from the nutrient solution surrounding the roots. The uptake rates of NO3– and NH4+ did not differ from each other and were about twice as high as the uptake rate of organic N when the different N forms were supplied separately in concentrations of 2 mM. Nevertheless, replacement of 50 % of the inorganic N with organic N was able to restore the N uptake to the same level as that in the presence of only inorganic N. Co-provision of NO3– did not affect glycine uptake, while the presence of glycine down-regulated NO3– uptake. The ratio between 13C and 15N were lower in shoots than in roots and also lower than the theoretical values, reflecting higher C losses via respiratory processes compared to N losses. It is concluded that organic N can constitute a significant N-source for wheat plants and that there is an interaction between the uptake of inorganic and organic nitrogen.

scholarly journals Role of Exogenous Carbohydrate and Amino Acid Sources on Biomass and Colchicine Production in Nontransformed Root Cultures of Gloriosa superba

2016 ◽  
Vol 25 (2) ◽  
pp. 247-256 ◽  
Author(s):  
Seemanti Ghosh ◽  
Biswajit Ghosh ◽  
Sumita Jha
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Biomass Yield ◽  
Fold Increase ◽  
Yield Enhancement ◽  
Root Cultures ◽  
Gloriosa Superba ◽  
Maximum Accumulation ◽  
Different Sources

Elicitation strategies were studied for yield enhancement of colchicine, produced by root cultures of Gloriosa superba. Adventitious root cultures were established and grown in media containing 3 mg/l NAA and 1 mg/l BA. Root cultures showed variations in biomass as well as colchicine production in the presence of different exogenous carbohydrates and amino acid. Among the different sources of carbohydrates used - fructose, sucrose and dextrose gave a substantially higher biomass yield than the control. Maximum biomass was obtained in the presence of fructose. Root cultures growing in mannitol supplemented medium resulted in maximum accumulation of colchicine (0.32%). Among the amino acids, serine and phenylalanine significantly enhanced colchicine accumulation in root cultures. 0.02 mM glutamine supplemented media showed maximum (ten-fold) increase of root biomass.Plant Tissue Cult. & Biotech. 25(2): 247-256, 2015 (December)

scholarly journals 386 Past, present and future of protein and N metabolism in ruminants

2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 169-170
Author(s):  
Gerald B Huntington ◽  
Joan H Eisemann
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Public Perception ◽  
National Research Council ◽  
Protein Composition ◽  
Publishing Research ◽  
Quantitative Information ◽  
Future Research ◽  
Ruminant Species ◽  
N Metabolism

Abstract By 1900, research identified urea, ammonia, and protein as the basic components of N metabolism in ruminants. Energy and protein metabolic interactions were outlined, amino acids were individually recognized as constituents of protein molecules, and the concept of enzyme-catalyzed reactions was established. Research stations were publishing research results and feeding recommendations. By 2000, the National Research Council built on the work of Henry and Morrison to create and revise publications of nutrient requirements for various classes of ruminants. Use of surgically altered animals, isotopically labelled molecules, and standardized laboratory analyses created quantitative information on ingestion, digestion, absorption, and metabolism of N-containing compounds. Protein composition and structure as well as the role of protein turnover to determine the concentration of cellular proteins were elucidated. Hypothesis-driven, statistically valid experimental designs created quantitative information on protein and amino acid requirements. Methionine was identified as the likely first-limiting amino acid for several ruminant species and production states. The internet and the advent of international symposia provided links among researchers around the globe. Today, multidisciplinary research teams are needed to enlarge the data base, to describe proteomics and metabolomics, and to integrate “big data” into insightful and useful models. Those models currently use or estimate rates and daily amounts of ruminal (in)degradability of dietary protein, ammonia production, urea recycling, microbial protein synthesis, postruminal protein digestion, metabolic fecal nitrogen, and amino acid absorption and metabolism. They predict use of metabolizable amino acids for maintenance, milk yield, growth, and fetal growth. Directions of future research include integration of functional roles of amino acids into recommended dietary supply and requirements, and focus on solutions to challenges presented by climate change, (in)sustainability of livestock production, and changes in public perception of humans’ use of ruminants and other animals.

Amino acid composition of xylem and phloem sap varies in canola genotypes differing in nitrogen- and sulfur-use efficiency

2011 ◽  
Vol 62 (3) ◽  
pp. 198 ◽  
Author(s):  
Tatjana Balint ◽  
Zdenko Rengel
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Xylem Sap ◽  
Vegetative Stage ◽  
Total N ◽  
Phloem Sap ◽  
Use Efficiency ◽  
N Use

There is little information on amino acid composition of xylem and phloem sap in canola genotypes differing in use efficiency of nitrogen (N) and/or sulfur (S). Four canola genotypes with either high or low N- and/or S-use efficiency indices were grown in a glasshouse using deficient or adequate N and/or S supply. Xylem sap was obtained by vacuum extraction 46 days after sowing. Phloem sap was collected via bleeding from the petioles of the maturing siliques 120 days after sowing. Among the genotypes, Wesway (N-use efficient) had the highest concentrations of total N, glutamine (235 mmol/L), and asparagine (14 mmol/L) in the xylem sap in the vegetative stage. In contrast, genotype Westar (classified previously as N-use inefficient) had the highest concentrations of most amino acids in the phloem sap among genotypes grown at deficient N supply. Compared with the other tested genotypes, Surpass 402 CL (S-use efficient) had a higher concentration of S, and Karoo (S-use inefficient) had higher concentrations of glutamate and methionine, in the xylem sap in the vegetative stage. Similarly, Karoo had a higher concentration of methionine under adequate S supply and of glutamate under deficient S in the phloem sap at maturity. In conclusion, in canola phloem sap, the most important amino acid for N transport is glutamine, and for S transport methionine and the glutathione-precursor glutamate. It does not appear there is a relationship between differential N- or S-use efficiency of canola genotypes and the concentration of N- or S-transporting amino acids in the phloem sap.

The main amino acids in xylem sap of Vitis vinifera L. var. Cabernet Franc during the vegetative cycle. Search for an amino acid marker

OENO One ◽  
1999 ◽  
Vol 33 (2) ◽  
pp. 49
Author(s):  
Corine Larchevêque ◽  
A. Casanova
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Aspartic Acid ◽  
Acid Content ◽  
Xylem Sap ◽  
Amino Acid Content ◽  
Total Amino Acid ◽  
Bud Burst ◽  
Phenological Stage ◽  
Total Amino Acid Content

<p style="text-align: justify;">Numerous studies have been carried out on the vine, must and wine, but few on sap. Main phenological stages i.e. bud burst, the flowering period, veraison and the ripening period have been well described. However, at the present time, no study is available identifying the main amino acids of the xylem sap, at the formentioned periods. Located within the « Graves de Pessac-Léognan » vineyard, the plot area studied has a clayey-chalky soil with a small amount of sand present. The cultivar Cabernet franc was grafted on the Fercal rootstock. Planted in June 1982, the vine was trained with Guyot pruning and no tillage. The density of the plantation was 5.550 vines per ha. Four rows of 21 vines were sampled.</p><p style="text-align: justify;">Analysis of xylem sap, by H.P.L.C., at the four stages, taken from several vintages, showed that the global content of amino acids varied year to year (LARCHEVÊQUE, 1998). The experiment reported on herein was carried out in order to determine both the main amino acids in the xylem sap and to identify a marker amongst them, having the same evolution as that of the global amino acid content from one phenological stage to the next. A pool of eight amino acids, all present in large quantities (about 80 p. cent of total amino acid content), was always noted : asparagine/glutamine, tyrosine, arginine, aspartic acid, glutamic acid, histidine and proline. Concentration levels of these components differed in sap, depending on the vintage, at the same phenological stage. At bud burst, as at the flowering period, the sap had a similar qualitative composition.</p><p style="text-align: justify;">It was noteworthy that aspartic acid evidenced the same evolution that of the total amino acid content (i.e. the same variation in percentage) from one phenological stage to the next. Aspartic acid should therefore be regarded as a « marker » of total amino acid content evolution during the vegetative cycle.</p>

The effects of amino acids on the growth and sporulation of Verticillium dahliae

1987 ◽  
Vol 65 (7) ◽  
pp. 1299-1302 ◽  
Author(s):  
D. R. Duncan ◽  
E. B. Himelick
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Verticillium Wilt ◽  
Verticillium Dahliae ◽  
Acer Saccharum ◽  
Sugar Maple ◽  
Xylem Sap ◽  
Amino Acid Content ◽  
Fungal Growth ◽  
Dry Weight

Conidial and dry weight production of Verticillium dahliae varied greatly depending on the amino acid used as the nitrogen source in Czapek's–Dox medium. Variable fungal growth was also noted when mixtures of amino acids were used and growth was dependent on the type and concentration of each amino acid in the mixture. Similar variation was obtained when sugar maple (Acer saccharum) sap was amended with individual amino acids. These results are examined in relation to the reported variation in the amino acid content of host xylem sap and in relation to verticillium wilt development.

scholarly journals An Amino Acid Ester of Menthol Elicits Defense Responses in Plants

2021 ◽  
Author(s):  
Chisato Tsuzuki ◽  
Masakazu Hachisu ◽  
Rihoko Iwabe ◽  
Yuna Nakayama ◽  
Yoko Nonaga ◽  
...  
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Plant Defense ◽  
Pest Control ◽  
Acid Ester ◽  
Transcript Level ◽  
Defense Responses ◽  
Amino Acid Ester ◽  
Defense Genes ◽  
Soybean Plants

Abstract Terpenoids, including menthol, exhibit potent abilities as plant defense potentiators in agriculture and horticulture. In the current study, we developed new terpene derivatives that consisted of menthol and various amino acids and that were expected to act as powerful plant defense potentiators. We used 6 amino acids possessing low-reactive sidechains to synthesize an array of amino acid ester of menthol (ment-aa) compounds. Transcript levels of two defense genes (pathogenesis-related 1 [PR1] and trypsin inhibitor [TI]) were evaluated in leaves of soybean plants 24 h after application of aquatic solution of menthol or menthol-aa, and revealed that the menthol menthyl ester of valine (ment-Val) alone elevated the transcript level of defense genes, and it did so only at the low dose of 1 µM, not at higher or lower doses tested. Moreover, it appeared that histone acetylation was involved in this effect. Application of ment-Val enabled soybean plants to sustain the increased transcript levels in their leaves for up to 3 days. Moreover, when ment-Val was additionally applied at day 4, at which time the transcript level had declined to the basal level, the transcript level was re-elevated, indicating the possibility that ment-Val could be repeatedly used to sustain pest control. Ment-Val was found to be chemically stable and effective for defense of several crop species. Collectively, these data show that terpenoid conjugates are useful for pest control instead of or in addition to pesticides.

Photosynthetic 14C-labeling patterns in developing soybeans

1973 ◽  
Vol 51 (8) ◽  
pp. 1505-1512 ◽  
Author(s):  
R. D. Noble ◽  
D. W. Long ◽  
J. W. Burley
Keyword(s):  
Amino Acids ◽  
Glycine Max ◽  
Amino Acid ◽  
Age Groups ◽  
Insoluble Residue ◽  
Controlled Environment ◽  
Age Group ◽  
Seed Age ◽  
Soybean Plants ◽  
14C Labeling

Soybean plants (Glycine max 'Harasoy') were cultured in a controlled environment room and studied at seven ages ranging from 16 to 40 days after flowering. Fruits from each age group were labeled by translocation of organic compounds from leaves which had photosynthetically incorporated 14CO2. Leaf blades, petioles, and seeds were extracted in boiling ethanol at the termination of labeling experiments. Seeds were also harvested and extracted 1, 2, and 8 days after labeling. Distribution of label in leaf blades and petioles was essentially the same in all age groups with more than 90% of the activity in petioles being found in carbohydrates. Little or no translocation of amino acids and organic acids was occurring. In seeds, most of the label appeared in the carbohydrate fraction immediately after labeling; however, at 2 and 8 days after labeling the label seemed to be transferred to lipids and the ethanol-insoluble residue. The rate of transfer decreased as a function of seed age. Levels of activity in the amino acid and organic acid fractions were low in all samples.

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