scholarly journals Different changes of soil nematode communities in replant and continuous-planting peach orchards and their indicative value for peach replant problem

2015 ◽  
Vol 52 (3) ◽  
pp. 261-269 ◽  
Author(s):  
X. Y. Li ◽  
Q. Z. Liu ◽  
Y. Z. Wang ◽  
H. Y. Sun ◽  
C. Q. Bai ◽  
...  
Keyword(s):  
Profile Analysis ◽  
Distribution Patterns ◽  
Soil Nematode ◽  
Plant Feeding ◽  
Key Factor ◽  
Nematode Diversity ◽  
Replant Problem ◽  
Peach Trees ◽  
And Function ◽  
Peach Orchard

Abstract Long-term changes of soil nematode diversity and distribution patterns in replant peach orchard (RPO) and continuous-planting peach orchard (CPPO) were assessed to evaluate different effects on nematode community and function by RPO and CPPO, in relation to peach replant problem from the point of soil fauna. Observations were conducted on a silt loam soil, and soil sampling was performed four times through the growing season of peach trees in the period from 2006 to 2008 in Pinggu, Beijing. The result showed that RPO differed from CPPO by its higher abundance of plant feeding nematodes but lower abundance of bacterivore nematodes, as well as significantly higher values of plant parasite index but lower nematode biodiversity. Obviously, the absolute abundance of Paratylenchus in RPO was higher than that in CPPO, which could be a key factor for the peach replant problems from the part of soil nematode. Nematode function indices and weighted nematode fauna profile analysis were no significantly different in the two peach ecosystems, but they represented an indication of high disturbance, N-enriched, bacterial decomposition pathway.

Responses of soil nematode communities to agroecological crop management systems

Nematology ◽  
2012 ◽  
Vol 14 (2) ◽  
pp. 209-221 ◽  
Author(s):  
Débora Cristina Santiago ◽  
Giovani de Oliveira Arieira ◽  
Edinei de Almeida ◽  
Maria de Fátima Guimarães
Keyword(s):  
Trophic Structure ◽  
Biological Indicators ◽  
Management Systems ◽  
Soil Nematode ◽  
Canavalia Ensiformis ◽  
Nematode Communities ◽  
Plant Feeding ◽  
Nematode Diversity ◽  
Crop Management Systems ◽  
The Impact

Soil nematodes are sensitive to human intervention and widely used as biological indicators of disruptions and alterations in soil quality. The aim of this work was to identify nematodes that are good biological indicators in maize crops under different management systems, and to establish the impact levels of these systems. Soil samples were collected over a 3-year period at a depth of 0.0-0.3 m in areas under six different management systems for maize (Zea mays) monoculture, and intercropped maize and Canavalia ensiformis. Six areas of native vegetation were also assessed to provide a reference for ecological balance. After identification and counting, nematode communities were characterised according to abundance (total and relative), diversity (identified genera and diversity indexes), trophic structure and ecological maturity (disturbance indexes). Nematodes proved to be good ecological indicators, responding to the systems employed. Intercropping maize and Canavalia ensiformis in at least one assessment year reduced disruption and increased nematode diversity, which were both verified based on specific indexes. It was also observed that the maize monoculture increased disruption leading to a drop in nematode fauna diversity and an increase in the incidence of plant-feeding nematodes.

scholarly journals Combined Effects of Methylated Cytosine and Molecular Crowding on the Thermodynamic Stability of DNA Duplexes

2021 ◽  
Vol 22 (2) ◽  
pp. 947
Author(s):  
Mitsuki Tsuruta ◽  
Yui Sugitani ◽  
Naoki Sugimoto ◽  
Daisuke Miyoshi
Keyword(s):  
Molecular Crowding ◽  
Dna Duplexes ◽  
Crowding Effect ◽  
Backbone Flexibility ◽  
Cpg Dinucleotides ◽  
Key Factor ◽  
Dna Backbone ◽  
A Cell ◽  
Stabilization Effect ◽  
And Function

Methylated cytosine within CpG dinucleotides is a key factor for epigenetic gene regulation. It has been revealed that methylated cytosine decreases DNA backbone flexibility and increases the thermal stability of DNA. Although the molecular environment is an important factor for the structure, thermodynamics, and function of biomolecules, there are few reports on the effects of methylated cytosine under a cell-mimicking molecular environment. Here, we systematically investigated the effects of methylated cytosine on the thermodynamics of DNA duplexes under molecular crowding conditions, which is a critical difference between the molecular environment in cells and test tubes. Thermodynamic parameters quantitatively demonstrated that the methylation effect and molecular crowding effect on DNA duplexes are independent and additive, in which the degree of the stabilization is the sum of the methylation effect and molecular crowding effect. Furthermore, the effects of methylation and molecular crowding correlate with the hydration states of DNA duplexes. The stabilization effect of methylation was due to the favorable enthalpic contribution, suggesting that direct interactions of the methyl group with adjacent bases and adjacent methyl groups play a role in determining the flexibility and thermodynamics of DNA duplexes. These results are useful to predict the properties of DNA duplexes with methylation in cell-mimicking conditions.

scholarly journals Cysteine-Free Proteins in the Immunobiology of Arthropod-Borne Diseases

2010 ◽  
Vol 2010 ◽  
pp. 1-10 ◽  
Author(s):  
J. Santiago Mejia ◽  
Erik N. Arthun ◽  
Richard G. Titus
Keyword(s):  
Plasmodium Falciparum ◽  
Amino Acid ◽  
Distribution Patterns ◽  
Structural Features ◽  
Structure And Function ◽  
Cysteine Residues ◽  
Distribution Analysis ◽  
And Function ◽  
Abundance And Distribution ◽  
Host Parasite

One approach to identify epitopes that could be used in the design of vaccines to control several arthropod-borne diseases simultaneously is to look for common structural features in the secretome of the pathogens that cause them. Using a novel bioinformatics technique, cysteine-abundance and distribution analysis, we found that many different proteins secreted by several arthropod-borne pathogens, includingPlasmodium falciparum, Borrelia burgdorferi, and eight species of Proteobacteria, are devoid of cysteine residues. The identification of three cysteine-abundance and distribution patterns in several families of proteins secreted by pathogenic and nonpathogenic Proteobacteria, and not found when the amino acid analyzed was tryptophan, provides evidence of forces restricting the content of cysteine residues in microbial proteins during evolution. We discuss these findings in the context of protein structure and function, antigenicity and immunogenicity, and host-parasite relationships.

scholarly journals Disparate Subcellular Localization Patterns of Pseudomonas aeruginosa Type IV Pilus ATPases Involved in Twitching Motility

2005 ◽  
Vol 187 (3) ◽  
pp. 829-839 ◽  
Author(s):  
Poney Chiang ◽  
Marc Habash ◽  
Lori L. Burrows
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Fluorescent Protein ◽  
Protein Localization ◽  
Yellow Fluorescent Protein ◽  
Distribution Patterns ◽  
Opportunistic Pathogen ◽  
Twitching Motility ◽  
Polar Localization ◽  
Type Iv ◽  
And Function

ABSTRACT The opportunistic pathogen Pseudomonas aeruginosa expresses polar type IV pili (TFP), which are responsible for adhesion to various materials and twitching motility on surfaces. Twitching occurs by alternate extension and retraction of TFP, which arise from assembly and disassembly of pilin subunits at the base of the pilus. The ATPase PilB promotes pilin assembly, while the ATPase PilT or PilU or both promote pilin dissociation. Fluorescent fusions to two of the three ATPases (PilT and PilU) were functional, as shown by complementation of the corresponding mutants. PilB and PilT fusions localized to both poles, while PilU fusions localized only to the piliated pole. To identify the portion of the ATPases required for localization, sequential C-terminal deletions of PilT and PilU were generated. The conserved His and Walker B boxes were dispensable for polar localization but were required for twitching motility, showing that localization and function could be uncoupled. Truncated fusions that retained polar localization maintained their distinctive distribution patterns. To dissect the cellular factors involved in establishing polarity, fusion protein localization was monitored with a panel of TFP mutants. The localization of yellow fluorescent protein (YFP)-PilT and YFP-PilU was independent of the subunit PilA, other TFP ATPases, and TFP-associated proteins previously shown to be associated with the membrane or exhibiting polar localization. In contrast, YFP-PilB exhibited diffuse cytoplasmic localization in a pilC mutant, suggesting that PilC is required for polar localization of PilB. Finally, localization studies performed with fluorescent ATPase chimeras of PilT and PilU demonstrated that information responsible for the characteristic localization patterns of the ATPases likely resides in their N termini.

scholarly journals Mumame: a software tool for quantifying gene-specific point-mutations in shotgun metagenomic data

2019 ◽  
Vol 3 ◽  
Author(s):  
Shruthi Magesh ◽  
Viktor Jonsson ◽  
Johan Bengtsson-Palme
Keyword(s):  
Microbial Communities ◽  
Point Mutations ◽  
Software Tool ◽  
Metagenomic Data ◽  
Data Sets ◽  
Resistance Mutations ◽  
Shotgun Metagenomics ◽  
Key Factor ◽  
Detection Of Mutations ◽  
And Function

Metagenomics has emerged as a central technique for studying the structure and function of microbial communities. Often the functional analysis is restricted to classification into broad functional categories. However, important phenotypic differences, such as resistance to antibiotics, are often the result of just one or a few point mutations in otherwise identical sequences. Bioinformatic methods for metagenomic analysis have generally been poor at accounting for this fact, resulting in a somewhat limited picture of important aspects of microbial communities. Here, we address this problem by providing a software tool called Mumame, which can distinguish between wildtype and mutated sequences in shotgun metagenomic data and quantify their relative abundances. We demonstrate the utility of the tool by quantifying antibiotic resistance mutations in several publicly available metagenomic data sets. We also identified that sequencing depth is a key factor to detect rare mutations. Therefore, much larger numbers of sequences may be required for reliable detection of mutations than for most other applications of shotgun metagenomics. Mumame is freely available online (http://microbiology.se/software/mumame).

scholarly journals Vitamin and mineral nutrition for the health and development of the children of Europe

2001 ◽  
Vol 4 (1a) ◽  
pp. 91-99 ◽  
Author(s):  
Andrew Tomkins
Keyword(s):  
Nutritional Status ◽  
Adult Health ◽  
Future Health ◽  
Childhood Nutrition ◽  
Nutritional Interventions ◽  
Childhood Diet ◽  
Structure Of Communities ◽  
Increased Risk ◽  
Key Factor ◽  
And Function

AbstractMost European countries are now affected by demographic transition and changing epidemiology of disease; the nutrition of children is increasingly recognised as crucial for present and future health. Adequate dietary intake and nutritional status among children are important for their own growth, development and function but there is now increasing evidence that childhood nutrition also influences adult health. Intrauterine nutrition influences adult morbidity and mortality, but the childhood diet and nutritional status modify the increased risk of being born small. Thus, childhood diet needs to be taken more seriously in order to improve a nation's health as well as producing bright, active children. A key factor is the recognition that nutritional interventions at different stages of the life cycle are necessary if childhood nutrition is to improve. The mosaic pattern of the geography and social structure of communities in Europe produces ‘poverty’ and ‘consumer’ related nutrition patterns - often side by side. At one extreme, there is an urgent need to prevent obesity; while at the other extreme serious attention is required towards the prevention of deficiency disorders, mostly related to poverty and social exclusion. Few European governments take childhood nutrition at all seriously. This paper reviews a number of micronutrient issues and makes the case for the development of evidence-based policies and programmes for improving the nutrition of children in Europe.

EFFECTS OF SEVIN ON PHYTOPHAGOUS MITES AND PREDATORS IN AN ONTARIO PEACH ORCHARD

1960 ◽  
Vol 40 (1) ◽  
pp. 198-201 ◽  
Author(s):  
Wm. L. Putman ◽  
D. C. Herne
Keyword(s):  
Panonychus Ulmi ◽  
Predacious Mite ◽  
Phytophagous Mites ◽  
European Red Mite ◽  
Peach Trees ◽  
Peach Orchard ◽  
Stethorus Punctillum

Numbers of the European red mite (Panonychus ulmi Koch) increased but those of the brown mite (Bryobia arborea Morgan & Anderson) and the peach silver mite (Vasates cornutus Banks) decreased after sprays of Sevin (N-methyl-1-naphthyl carbamate) were applied to peach trees. Sevin practically eliminated the predacious mite Typhlodromus rhenanus Oudms., and larvae and pupae of Stethorus punctillum Weise, and greatly reduced the numbers of adults of S. punctillum, chrysopid larvae, and spiders.

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