Activation of potassium released from soil by root-secreted organic acids in different varieties of tobacco (Nicotiana tabacum)

2020 ◽  
Vol 47 (4) ◽  
pp. 318 ◽  
Author(s):  
Zhi-Xiao Yang ◽  
Shi-Zhou Yu ◽  
Ying-Chao Lin ◽  
Wei-Jun Zhang ◽  
Yi Wang ◽  
...  
Keyword(s):  
Nicotiana Tabacum ◽  
Organic Acids ◽  
Organic Ligands ◽  
The Other ◽  
Cyclic Process ◽  
Low Concentrations ◽  
High K ◽  
Utilisation Rate ◽  
Underlying Mechanisms ◽  
Tobacco Roots

Organic acids secreted from the roots of plants play important roles in nutrient acquisition and metal detoxification; however, the precise underlying mechanisms of these processes remain poorly understood. In the present study we examined the content of organic acids exuded from roots and the effects of these organic acids on the activation of slowly available potassium (K) at different K levels, including normal K supply and K-deficient conditions. In addition, the study system also comprised a high-K tobacco variety (ND202) and two common ones (K326 and NC89). Our results showed that high-K varieties exhibited significantly higher contents of organic acids in its root exudates and available K in both rhizosphere and non-rhizosphere soils than the other varieties. This research also suggested that a cyclic process in which soil was acidified after being complexed by organic acids was involved in the release of slowly available K, and that this process primarily depended on the soil pH at high organic acids concentrations, but the complexation of organic ligands became dominant at low concentrations. In conclusion, tobacco roots secrete organic acids to increase available K content and improve the utilisation rate of soil K. High-K varieties probably enhance slowly available K activation by secreting relatively high amounts of organic acids, thus leading to more available K in soil for absorption by plants.

scholarly journals Organic Acids Exuded From Roots Increase the Available Potassium Content in the Rhizosphere Soil: A Rhizobag Experiment in Nicotiana tabacum

HortScience ◽  
2019 ◽  
Vol 54 (1) ◽  
pp. 23-27 ◽  
Author(s):  
Yongfeng Yang ◽  
Zhixiao Yang ◽  
Shizhou Yu ◽  
Hongli Chen
Keyword(s):  
Organic Acids ◽  
Rhizosphere Soil ◽  
Abiotic Stress Tolerance ◽  
Total Content ◽  
Utilization Rate ◽  
Higher Plant ◽  
Activation Effect ◽  
High K ◽  
K Deficiency ◽  
Tobacco Roots

Organic acid secretion from higher plant roots into the rhizosphere soil plays an important role in nutrient acquisition and metal detoxification; however, their precise functions and the related mechanisms in abiotic stress tolerance remain poorly understood. Tobacco is an important crop plant, so thoroughly elucidating these factors in tobacco is of high priority. In the present study, the activation effect on soil potassium (K), contents of exuded organic acids, and physiological changes in the roots of various tobacco varieties under both normal K supply and K-deficiency stress were investigated. Our results showed that one high-K variety (ND202) exhibited a significantly higher total content of organic acids in the root exudates and the highest available K content in the rhizosphere soil, compared with two common ones (K326 and NC89). Moreover, the high-K tobacco variety was less affected in terms of root vigor under K-deficiency stress, and displayed greater increases in the activities of the stress-resistant enzymes consisting of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT). Taken together, these results provide evidence that tobacco roots exude large amounts of organic acids to increase the available K content in the rhizosphere soil and improve the utilization rate of soil K.

scholarly journals The Influence of Long and Short Cycle Schemes of Self-Cycling Fermentation on the Growth of E. Coli and S. Cerevisiae

2021 ◽  
Author(s):  
Yusheng Tan ◽  
Lisa Y. Stein ◽  
Dominic Sauvageau
Keyword(s):  
Growth Patterns ◽  
The Other ◽  
Cyclic Process ◽  
Cell Replication ◽  
Short Cycle ◽  
Carbon Dioxide Evolution Rate ◽  
Limiting Nutrient ◽  
Characteristic Points ◽  
Underlying Mechanisms ◽  
Key Events

Abstract Self-cycling fermentation (SCF), a cyclic process in which cells divide once per cycle, has been shown to lead to improvements in productivity during bioconversion and, often, whole-culture synchronization. Previous studies have found that in some cases, the completion of synchronized cell replication occurred simultaneously with depletion of a limiting nutrient. However, exceptions were also observed when the end of cell doubling occurred before the exhaustion of the limiting nutrient. In order to better understand the underlying mechanisms and impacts of these growth patterns on bioprocessing, we investigated the growth of Escherichia coli and Saccharomyces cerevisiae in long- and short-cycle SCF strategies. Three characteristic events linked to SCF cycles were identified: (1) the completion of synchronized cell replication, (2) the depletion or a plateau of the limiting nutrient, and (3) characteristic points of control parameters (e.g., the minimum of dissolved oxygen and the maximum of carbon dioxide evolution rate). Three major trends stemming from this study and SCF literature were observed: (A) co-occurrence of the three key events in SCF cycles, (B) cycles for which cell replication ended prior to the co-occurrence of the other two events, and (C) cycles for which the time of depletion or a plateau of the limiting nutrient occurred later than the concurrence of the other two events. Based on these observations, a novel definition for SCF is proposed.

Effect of C6-Volatiles on Bioluminescent Plant Pathogens

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 557d-557
Author(s):  
Jennifer Warr ◽  
Fenny Dane ◽  
Bob Ebel
Keyword(s):  
Biological Activity ◽  
Bacterial Growth ◽  
Xanthomonas Campestris ◽  
Plant Pathogens ◽  
Genetically Engineered ◽  
The Other ◽  
Computer Assisted ◽  
Signal Molecules ◽  
Low Concentrations

C6 volatile compounds are known to be produced by the plant upon pathogen attack or other stress-related events. The biological activity of many of these substances is poorly understood, but some might produce signal molecules important in host–pathogen interactions. In this research we explored the possibility that lipid-derived C6 volatiles have a direct effect on bacterial plant pathogens. To this purpose we used a unique tool, a bacterium genetically engineered to bioluminesce. Light-producing genes from a fish-associated bacterium were introduced into Xanthomonas campestris pv. campestris, enabling nondestructive detection of bacteria in vitro and in the plant with special computer-assisted camera equipment. The effects of different C6 volatiles (trans-2 hexanal, trans-2 hexen-1-ol and cis-3 hexenol) on growth of bioluminescent Xanthomonas campestris were investigated. Different volatile concentrations were used. Treatment with trans-2 hexanal appeared bactericidal at low concentrations (1% and 10%), while treatments with the other volatiles were not inhibitive to bacterial growth. The implications of these results with respect to practical use of trans-2 hexanal in pathogen susceptible and resistant plants will be discussed.

Hated but still human: Metadehumanization leads to greater hostility than metaprejudice

2021 ◽  
pp. 136843022097903
Author(s):  
Alexander P. Landry ◽  
Elliott Ihm ◽  
Jonathan W. Schooler
Keyword(s):  
Public Opinion ◽  
The Other ◽  
Intergroup Conflict ◽  
Negative Bias ◽  
Intergroup Conflicts ◽  
Underlying Mechanisms ◽  
Public Opinion Polls ◽  
Opinion Polls

Metadehumanization, the perception that members of an outgroup dehumanize your group, has been found to exacerbate intergroup conflict by inspiring reciprocal dehumanization of the offending outgroup. Moreover, metadehumanization is distinct from metaprejudice (i.e., the perception that an outgroup hates your group). Given the mutual animosity reported in public opinion polls toward the other side, we believed US–Russia relations would be a worthwhile context in which to extend this model. Therefore, we measured Americans’ levels of metadehumanization and metaprejudice of Russians to determine the association between these perceptions and their hostility toward Russians (Study 1). In this novel intergroup conflict, metadehumanization remained a consequential predictor of outgroup hostility over and above metaprejudice, suggesting that it can exacerbate a broader range of intergroup conflicts than those heretofore examined. Given these findings, we then sought to experimentally differentiate between metadehumanization and metaprejudice. In Study 2, we manipulated both metadehumanization and metaprejudice to (a) determine whether one or both cause greater outgroup hostility and (b) elucidate the underlying mechanisms by which they may produce this effect. Whereas metadehumanization produced greater hostility, metaprejudice did not. Moreover, although both metaperceptions inspired greater prejudice, only metadehumanization led to greater dehumanization. We conclude that metadehumanization may be a particularly potent fomenter of hostility because it inspires reciprocal dehumanization over and above more general negative bias.

On Two New Nematodes (Aphelenchoidea) from Tobacco Roots in India

1970 ◽  
Vol 44 (3-4) ◽  
pp. 323-328 ◽  
Author(s):  
R. S. Tandon ◽  
S. P. Singh
Keyword(s):  
New Species ◽  
Nicotiana Tabacum ◽  
Hot Water ◽  
Tobacco Plants ◽  
Alcohol Mixture ◽  
Two New Species ◽  
Tobacco Roots ◽  
Pure Glycerine

Two new species belonging to two different families of the super-family Aphelenchoidea are described. The material was obtained from the roots of tobacco plants, Nicotiana tabacum.The worms were killed by hot water, fixed in F.A.A. solution, cleared in 1% glycerine alcohol mixture and mounted in pure glycerine.

scholarly journals Emergence of cultural intelligence and global mindset capital: a multilevel model

2016 ◽  
Vol 24 (2) ◽  
pp. 106-122 ◽  
Author(s):  
Jase R. Ramsey ◽  
Amine Abi Aad ◽  
Chuandi Jiang ◽  
Livia Barakat ◽  
Virginia Drummond
Keyword(s):  
Multilevel Model ◽  
Cultural Intelligence ◽  
The Other ◽  
Global Mindset ◽  
Firm Level ◽  
Content Type ◽  
Individual Level ◽  
Other Hand ◽  
Underlying Mechanisms ◽  
Conceptual Study

Purpose The purpose of this paper is to establish under which conditions researchers should use the constructs cultural intelligence (CQ) and global mindset (GM). The authors further seek to understand the process through which these constructs emerge to a higher level and link unit-level knowledge, skills and abilities (KSAs) capital to pertinent firm-level outcomes. Design/methodology/approach This paper is a conceptual study with a multilevel model. Findings This paper differentiates two similar lines of research occurring concordantly on the CQ and GM constructs. Next, the authors develop a multilevel model to better understand the process through which CQ and GM emerge at higher levels and their underlying mechanisms. Finally, this paper adds meaning to the firm-level KSAs by linking firm-level KSAs capital to pertinent firm-level outcomes. Research limitations/implications The conclusion implies that researchers should use CQ when the context is focused on interpersonal outcomes and GM when focused on strategic outcomes. The multilevel model is a useful tool for scholars to select which rubric to use in future studies that have international managers as the subjects. The authors argue that if the scholar is interested in an individual’s ability to craft policy and implement strategy, then GM may be more parsimonious than CQ. On the other hand, if the focus is on leadership, human resources or any other relationship dependent outcome, then CQ will provide a more robust measure. Practical implications For practitioners, this study provides a useful tool for managers to improve individual-level commitment by selecting and training individuals high in CQ. On the other hand, if the desired outcome is firm-level sales or performance, the focus should be on targeting individuals high in GM. Originality/value This is the first theoretical paper to examine how CQ and GM emerge to the firm level and describe when to use each measure.

Sodium Benzoate Inhibits Growth of or Inactivates Listeria monocytogenes

1988 ◽  
Vol 51 (7) ◽  
pp. 525-530 ◽  
Author(s):  
MOUSTAFA A. EL-SHENAWY ◽  
ELMER H. MARTH
Keyword(s):  
Listeria Monocytogenes ◽  
Incubation Period ◽  
Sodium Benzoate ◽  
The Other ◽  
Complete Inhibition ◽  
Initial Population ◽  
Limited Growth ◽  
Complete Inactivation ◽  
Low Concentrations ◽  
Slight Growth

The ability of Listeria monocytogenes to grow or survive was determined using tryptose broth at pH 5.6 or 5.0, supplemented with 0, 0.05. 0.1, 0.15. 0.2. 0.25 or 0.3% sodium benzoate, and incubated at 4,13,21 or 35°C. The bacterium grew in benzoate-free controls under all conditions except at 4°C and pH 5.0. At pH 5.6 and 4°C, after 60 d, L. monocytogenes (initial population ca. 103/ml) was inactivated by 0.2, 0.25 and 0.3% sodium benzoate. Other concentrations of benzoate permitted slight growth during the first 36 d of incubation followed by a decrease in populations of the pathogen. At pH 5.0 and 4°C, from 0.15 to 0.3% benzoate completely inactivated the pathogen in 24 to 30 d, whereas the other concentrations caused a gradual decrease in the population during the 66-d incubation period. At 13°C and pH 5.6, L. monocytogenes grew (more at lower than higher concentrations of benzoate) in the presence of all concentrations of benzoate except 0.25 or 0.3%, which prohibited growth throughout a 264-h incubation period. Reducing the pH to 5.0 minimized growth at the two low concentrations of benzoate and caused slight decreases in population at the other concentrations of benzoate. At 21 and 35°C and pH 5.6, appreciable growth of L. monocytogenes occurred in the presence of 0.2% or less sodium benzoate, whereas higher concentrations were inhibitory, permitting little if any growth by the pathogen. Reducing the pH to 5.0 allowed limited growth of the pathogen at 21 and 35°C when the medium contained 0.05 or 0.1% sodium benzoate. Higher concentrations caused either complete inhibition or inhibition plus partial or complete inactivation of the pathogen during incubations of 117 h at 21°C or 78 h at 35°C.

scholarly journals Acquisition and metabolism of carbon in the Ochrophyta other than diatoms

2017 ◽  
Vol 372 (1728) ◽  
pp. 20160400 ◽  
Author(s):  
John A. Raven ◽  
Mario Giordano
Keyword(s):  
Carbon Metabolism ◽  
Brown Algae ◽  
C4 Photosynthesis ◽  
Genomic Data ◽  
Diagnostic Value ◽  
The Other ◽  
High K ◽  
C4 Metabolism ◽  
Low Amplitude ◽  
C3 Metabolism

The acquisition and assimilation of inorganic C have been investigated in several of the 15 clades of the Ochrophyta other than diatoms, with biochemical, physiological and genomic data indicating significant mechanistic variation. Form ID Rubiscos in the Ochrophyta are characterized by a broad range of kinetics values. In spite of relatively high K 0.5 CO 2 and low CO 2 : O 2 selectivity, diffusive entry of CO 2 occurs in the Chrysophyceae and Synurophyceae. Eustigmatophyceae and Phaeophyceae, on the contrary, have CO 2 concentrating mechanisms, usually involving the direct or indirect use of . This variability is possibly due to the ecological contexts of the organism. In brown algae, C fixation generally takes place through a classical C3 metabolism, but there are some hints of the occurrence of C4 metabolism and low amplitude CAM in a few members of the Fucales. Genomic data show the presence of a number of potential C4 and CAM genes in Ochrophyta other than diatoms, but the other core functions of many of these genes give a very limited diagnostic value to their presence and are insufficient to conclude that C4 photosynthesis is present in these algae. This article is part of the themed issue ‘The peculiar carbon metabolism in diatoms'.

On the Nature of Weak Spots in High-k Layers Submitted to Anneals

2004 ◽  
Vol 811 ◽  
Author(s):  
J. Pétry ◽  
W. Vandervorst ◽  
O. Richard ◽  
T. Conard ◽  
P. DeWolf ◽  
...  
Keyword(s):  
Atomic Force Microscopy ◽  
Strong Correlation ◽  
Positive Charge ◽  
The Other ◽  
Physical Analysis ◽  
Force Microscopy ◽  
Atomic Force ◽  
Other Hand ◽  
High K ◽  
High K Dielectric

ABSTRACTIn the path to the introduction of high-k dielectric into IC components, a large number of challenges have still to be solved. Some of the major issues concern the low mobility of carriers and the reliability of the devices. Trapped charges in the stack have been identified as being the cause of these issues. With this in mind, we used Conducting Atomic Force Microscopy, combined with physical analysis to understand the nature of these charges. In this contribution, we have studied the uniformity of thin HfO2 layers, with and without anneal. The Conducting Atomic Force microscopy measurements show spots of higher conductivity. Recording local IV's in those ‘weak’ spots suggests that they consist of positive charge. On the other hand, XPS and ToFSIMS analysis show a diffusion of the interfacial SiO2 upwards into the high-k layer. Finally, the comparison of samples with differing high-k material and crystallinity indicates a strong correlation between the weak spots and the presence of silicon in the film.

scholarly journals The clinical cross-reactivity and immunological cross-antigenicity of wheat and barley

2021 ◽  
Author(s):  
Shohei Kubota ◽  
Yuji Aoki ◽  
Tomomi Sskai ◽  
Katsumasa Kitamura ◽  
Teruaki Matsui ◽  
...  
Keyword(s):  
Oral Immunotherapy ◽  
Cross Reactivity ◽  
The Other ◽  
Enzyme Linked Immunosorbent Assay ◽  
Wheat Allergy ◽  
Extract Concentration ◽  
Low Concentrations ◽  
High Concentrations ◽  
Food Challenges ◽  
Elisa Inhibition

Background: Some patients with a wheat allergy have been reported to show clinical cross-reactivity to barley. However, it is not clear whether the development of barley allergy in patients with a wheat allergy is due to cross-antigenicity between wheat and barley. In our study, we aimed to determine the clinical cross-reactivity and immunological cross-antigenicity of wheat and barley. Methods: We compared the results of barley oral food challenges (OFCs) before oral immunotherapy (OIT) for wheat with those after OIT in nine patients with a wheat allergy to estimate the clinical cross-reactivity of wheat and barley. Moreover, we performed enzyme-linked immunosorbent assay (ELISA) inhibition and immunoblotting inhibition using serum from seven patients allergic to wheat and barley. Results: Nine patients who had positive barley-OFC results performed before OIT for wheat were all negative on barley-OFC performed after OIT. In ELISA inhibition, preincubation of serum from patients allergic to wheat and barley with a high barley extract concentration inhibited binding of IgE to wheat extract by less than 10%. On the other hand, wheat and barley extracts equally inhibited binding to barley sIgE at high concentrations. In the immunoblotting inhibition test, the spots of wheat were inhibited but weakly by barley extracts, and most of the spots of barley were inhibited even by low concentrations of the wheat and barley extract. Conclusion: We showed that barley allergy associated with wheat allergy is caused by cross-reactivity from wheat. The OIT for wheat was one of the promising options for barley allergy.

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