scholarly journals Growth yield and selection of nosZ clade II types in a continuous enrichment culture of N2 O respiring bacteria

2018 ◽  
Vol 10 (3) ◽  
pp. 239-244 ◽  
Author(s):  
Monica Conthe ◽  
Lea Wittorf ◽  
J. Gijs Kuenen ◽  
Robbert Kleerebezem ◽  
Sara Hallin ◽  
...  
Keyword(s):  
Enrichment Culture ◽  
Growth Yield ◽  
Continuous Enrichment ◽  
Selection Of

Co-selection may explain high rates of ciprofloxacin non-susceptible Escherichia coli from retail poultry reared without prior fluoroquinolone exposure

2013 ◽  
Vol 62 (11) ◽  
pp. 1743-1746 ◽  
Author(s):  
Paul Robert Ingram ◽  
Benjamin A. Rogers ◽  
Hanna E. Sidjabat ◽  
Justine S. Gibson ◽  
Timothy J. J. Inglis
Keyword(s):  
Escherichia Coli ◽  
Enrichment Culture ◽  
Fluoroquinolone Resistance ◽  
Gene Encoding ◽  
Selective Enrichment ◽  
E Coli ◽  
Selective Pressures ◽  
Resistance Determinants ◽  
Small Collection ◽  
Selection Of

Australia has never permitted fluoroquinolone use in food-producing animals. We examined local retail poultry for contamination with fluoroquinolone non-susceptible Escherichia coli, then explored the hypothesis that their presence may be due to co-selection of resistance determinants. Between August and November 2010, samples from 30 locally produced, uncooked retail poultry carcasses from four different processing centres underwent selective enrichment culture for ciprofloxacin non-susceptible E. coli. Their chromosomal- and plasmid-mediated resistance determinants were characterized, and phylogenetic analysis and transformation experiments were performed. Unexpectedly, we found nine (30 %) of our small collection of poultry samples carried fluoroquinolone non-susceptible E. coli of which nearly half possessed aac(6')-Ib-cr, a novel plasmid-mediated gene encoding an aminoglycoside acetylating enzyme that also confers fluoroquinolone resistance. All nine isolates were co-resistant to amoxicillin, gentamicin, tetracycline and trimethoprim/sulfamethoxazole – all antibiotic classes that are registered for use in poultry reared for food production within Australia. Their unique phylogenetic relatedness suggested clonal dissemination driven by non-fluoroquinolone selective pressures. aac(6')-Ib-cr was successfully transformed and selected for using non-fluoroquinolone antibiotic pressure. Vertical and perhaps horizontal co-selection may be contributing to the emergence of fluoroquinolone resistance in poultry and could play a similar role in the human setting. This suggests that preservation of the usefulness of fluoroquinolones may require more than just restriction of their use in isolation from other interventions.

scholarly journals Biodegradation of cis-Dichloroethene as the Sole Carbon Source by a β-Proteobacterium

2002 ◽  
Vol 68 (6) ◽  
pp. 2726-2730 ◽  
Author(s):  
Nicholas V. Coleman ◽  
Timothy E. Mattes ◽  
James M. Gossett ◽  
Jim C. Spain
Keyword(s):  
Enrichment Culture ◽  
Growth Yield ◽  
Utilization Rate ◽  
Specific Substrate ◽  
Resting Cells ◽  
Aerobic Bacterium ◽  
16S Ribosomal Dna ◽  
Epoxidation Reaction ◽  
Specific Substrate Utilization Rate ◽  
Ribosomal Dna Sequence

ABSTRACT An aerobic bacterium capable of growth on cis-dichloroethene (cDCE) as a sole carbon and energy source was isolated by enrichment culture. The 16S ribosomal DNA sequence of the isolate (strain JS666) had 97.9% identity to the sequence from Polaromonas vacuolata, indicating that the isolate was a β-proteobacterium. At 20°C, strain JS666 grew on cDCE with a minimum doubling time of 73 ± 7 h and a growth yield of 6.1 g of protein/mol of cDCE. Chloride analysis indicated that complete dechlorination of cDCE occurred during growth. The half-velocity constant for cDCE transformation was 1.6 ± 0.2 μM, and the maximum specific substrate utilization rate ranged from 12.6 to 16.8 nmol/min/mg of protein. Resting cells grown on cDCE could transform cDCE, ethene, vinyl chloride, trans-dichloroethene, trichloroethene, and 1,2-dichloroethane. Epoxyethane was produced from ethene by cDCE-grown cells, suggesting that an epoxidation reaction is the first step in cDCE degradation.

scholarly journals Growth, Yield, Efficiency, and Fruit Quality of Five Navel Orange Clones During 4 Years

1969 ◽  
Vol 68 (4) ◽  
pp. 405-411
Author(s):  
Agripino Pérez-López ◽  
Carlos J. Torres
Keyword(s):  
Puerto Rico ◽  
Growth Yield ◽  
Tree Height ◽  
Fruit Weight ◽  
Navel Orange ◽  
Yield Efficiency ◽  
Acid Ratio ◽  
Canopy Volume ◽  
Selection Of

Clone 7 can increase three-fold the production of navel oranges in Puerto Rico. Clone 7 produced 293 fruits per tree. The number and weight of fruits per tree increased with age, whereas the size and fruit weight, navel volume and peel weight diminished. Growth measurements such as rootstock and scion diameter, scion/rootstock ratio, canopy diameter, tree height, and canopy volume are not as good parameters for the selection of navel orange clones as the number of fruits per m3 of canopy volume. Screening for varieties according to yield revealed that clones 5 and 7 were the most productive and that they should be recommended to the citrus growers. Clones 5 and 7 also had the highest Brix and acidity values, and an intermediate pH, which contribute to an appropriate Brix/acid ratio, typical of the high quality of these navel clones. The smallest fruits had significantly the highest juice percentage.

Performance of Fenugreek (Trigonella foenum-graecum L.) Genotypes towards Growth, Yield and UPOV Properties

2021 ◽  
Author(s):  
Gulsum Yaldiz ◽  
Mahmut Camlica
Keyword(s):  
Genetic Diversity ◽  
Growth Yield ◽  
Yield Traits ◽  
Pca Analysis ◽  
International Union ◽  
Trigonella Foenum Graecum ◽  
New Varieties ◽  
Superior Genotypes ◽  
Trigonella Foenum Graecum L ◽  
Selection Of

Background: Genetic diversity is referred to the diversity present within different genotypes of same species, serves as the most valuable reservoir in providing variability for various traits. This variability would provide a basis for improving the crop in breeding program. The present study aimed to assessment of genetic diversity and selection of superior genotypes for fenugreek breeding. Methods: In this study, 75 fenugreek genotypes with cultivars (Çiftçi and Gürarslan) were used and these genotypes were established in augmented trial design. Each genotype was analyzed for morphological and yield traits and nineteen traits were scored according to the International Union for the Protection of New Varieties of Plants (UPOV). Result: As a result of the study, PI 568215 and PI 577712 were noted as promising genotypes for seed yield and protein content, respectively. Dendrogram analysis showed that same origin genotypes were found in different main groups. Correlation analysis revealed that 22 positive or negative correlations were found among the examined properties. PCA analysis results were found among the examined properties and total variation was noted as 39.95%.

scholarly journals Continuous Enrichment Culture and Molecular Monitoring to Investigate the Microbial Diversity of Thermophiles Inhabiting Deep-Sea Hydrothermal Ecosystems

2005 ◽  
Vol 50 (3) ◽  
pp. 138-144 ◽  
Author(s):  
Anne Postec ◽  
Laurent Urios ◽  
Françoise Lesongeur ◽  
Bernard Ollivier ◽  
Joël Querellou ◽  
...  
Keyword(s):  
Microbial Diversity ◽  
Deep Sea ◽  
Enrichment Culture ◽  
Molecular Monitoring ◽  
Hydrothermal Ecosystems ◽  
Continuous Enrichment

ENRICHMENT CULTURE TECHNIQUES FOR SELECTION OF CELL CULTURE STRAINS WITH DESIRABLE PHYSIOLOGICAL AND GENETIC PROPERTIES

1971 ◽  
Vol 68 (1_Suppl) ◽  
pp. S126-S136 ◽  
Author(s):  
Gordon Sato ◽  
Jeffrey Clark ◽  
Martin Posner ◽  
Hyam Leffert ◽  
Dieter Paul ◽  
...  
Keyword(s):  
Cell Culture ◽  
Enrichment Culture ◽  
Tumour Cells ◽  
Mammary Tumour ◽  
Hybrid Cells ◽  
Culture Techniques ◽  
Experimental Approaches ◽  
Selection Of

ABSTRACT Experimental approaches for selecting hormone-dependent cells, hybrid cells, and haploid cells are discussed. Experiments are described for isolating mammary tumour cells which are dependent on the presence of prolactin and insulin for growth.

scholarly journals "Selection of several genotype of genetically modified rice (Oryza sativa L.) under the conditions of AlNajaf Governorate in terms of vegetative growth, yield and its components. "

2021 ◽  
Vol 8 (2) ◽  
Author(s):  
Mohammed H. N. AL-Jana ◽  
Faisal M. M. AL-Taher ◽  
Fuad R. Abdel Hussain
Keyword(s):  
Oryza Sativa L ◽  
Flag Leaf ◽  
Block Design ◽  
Growth Yield ◽  
Field Performance ◽  
Research Station ◽  
Randomized Complete Block Design ◽  
Biological Yield ◽  
Selection For ◽  
Selection Of

"The experiment was carried out during growing season (2018-2019) at the Rice Research Station in Mishkhab / AL-Najaf-Iraq, The seeds of 27 genotypes were sowing with the aim of selecting the best economically yielding genotypes for cultivation under the conditions of ALNajaf. The experiment was arranged with a randomized complete block design with four replication. The results showed significant differences between the genotypes for all the traits under study. The G27 genotype showed superiority for traits exceeded, number of grains per panicle, grain yield ton. ha-1 , the biological yield ton. ha-1 and the sterility percentage (%), with averages were 220.17, 13.34, 27.95, and 4.48, respectively. Whereas, the genotype G14 was superior with the characteristics of the number of fertile panicles and the duration of fullness the grain, which averaged 37.00 and 82.25 respectively, while the genotype G13 was significant for weight of 1000 grains (g), and the genotype G21 was superior with the flag leaf area which gave an average 32.45 cm2 . Through this study, genotypes (G1, G2, G12, G15, G16, G17, G18, G21, G25 and G27) showed the best field performance in terms of growth characteristics and the outcome of their selection for the second agricultural season."

scholarly journals An overview of adaptative responses to drought stress in Eucalyptus spp.

2017 ◽  
Vol 67 (1) ◽  
pp. 86-96 ◽  
Author(s):  
Ezzeddine Saadaoui ◽  
Kaouther Ben Yahia ◽  
Samir Dhahri ◽  
Mohamed Lahbib Ben Jamaa ◽  
Mohamed Larbi Khouja
Keyword(s):  
Arid Regions ◽  
Growth Yield ◽  
Great Opportunity ◽  
Choice Of Species ◽  
Species Hybrids ◽  
Physiological And Biochemical ◽  
High Adaptation ◽  
Semi Arid ◽  
Adaptation To Drought ◽  
Selection Of

Abstract Eucalyptus is a plant frequently present and cultivated in arid regions because of its high adaptation to drought. Furthermore, it is known by its numerous species which represents a great opportunity to choose several tolerant species with variable uses. Therefore, the choice of species, hybrids or genotypes resistant to aridity becomes a necessity before any plantation in regions and countries characterized by semi-arid, arid and Saharan climates. Our review shows an important effect of drought on anatomical, physiological and biochemical parameters of Eucalyptus spp. Indeed, water stress acts directly on growth, yield and response to pests. However, the response to drought varies significantly among species, genotypes, hybrids and clones. This result represents a field for the selection of eucalypts tolerant and adapted to water deficit or climate change.

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