scholarly journals Introgression Progress for Phenotypic Traits and Parent-progeny Diversity at Advanced Segregation Population From Oryza Barthii and Oryza Glaberrima/oryza Sativa Crosses

2022 ◽  
Author(s):  
Bosede Popoola ◽  
Daniel Adewale ◽  
Christopher Okonji ◽  
Morufat Balogun
Keyword(s):  
Genotypic Variation ◽  
Principal Component ◽  
Tiller Number ◽  
Phenotypic Traits ◽  
Oryza Glaberrima ◽  
Intermediate Group ◽  
Rice Genetic ◽  
1000 Grain Weight ◽  
Oryza Barthii ◽  
Variance Explained

Abstract Rice is a cereal staple of global fame and importance. Oryza barthii, a wild species holds significant traits and its utilization in rice breeding is rare. This study traced introgression trend of heritable traits in the offspring of O. barthii with an Africa-Asian progenitor to F8 and assessed diversity between the parents and the F8 population. Significant (P<0.05) genotypic variation existed for all the traits except tiller number, panicle/meter squared, grains/panicle and 1000 grain weight. Grains/panicle and days to 50% flowering had respective least (3.34%) and highest (96.32%) broad sense heritabilities. All traits had lower GCV compared to PCV. The least (5.28% and 8.05%) and the highest (90.8% and 98.1%) GCV and PCV were respectively from grains/panicle and tiller number. Clear variations on the panicles and grains include: variations in sizes, shapes, colours, presence or absence of awns. The total variance explained by five principal component axes was 80.1%. Plant height at maturity was the only trait with significant (p ≤ 0.01) correlation and regression between F6 and F7. Progenies resemblance to Parent 1(IRGC 104084) retrogressively declined but parent-offspring to parent 2 (TGS 25) progressively increased from F6 to F8. Three visible groups of rice type in this study were: the O. barthii (11%), O. sativa (67%) and the intermediate group (22%). This research has added to rice genetic resources; an investigation of the nutritional status of the progenies would be an interesting research.

scholarly journals Evaluation of indigenous aromatic rice cultivars from sub-Himalayan Terai region of India for nutritional attributes and blast resistance

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Debayan Mondal ◽  
Prudveesh Kantamraju ◽  
Susmita Jha ◽  
Gadge Sushant Sundarrao ◽  
Arpan Bhowmik ◽  
...  
Keyword(s):  
Nutritive Value ◽  
Amylose Content ◽  
Blast Resistance ◽  
Starch Content ◽  
Low Cost ◽  
Principal Component ◽  
Blast Disease ◽  
Basmati Rice ◽  
Phenotypic Traits ◽  
Rice Cultivars

AbstractIndigenous folk rice cultivars often possess remarkable but unrevealed potential in terms of nutritional attributes and biotic stress tolerance. The unique cooking qualities and blissful aroma of many of these landraces make it an attractive low-cost alternative to high priced Basmati rice. Sub-Himalayan Terai region is bestowed with great agrobiodiversity in traditional heirloom rice cultivars. In the present study, ninety-nine folk rice cultivars from these regions were collected, purified and characterized for morphological and yield traits. Based on traditional importance and presence of aroma, thirty-five genotypes were selected and analyzed for genetic diversity using micro-satellite marker system. The genotypes were found to be genetically distinct and of high nutritive value. The resistant starch content, amylose content, glycemic index and antioxidant potential of these genotypes represented wide variability and ‘Kataribhog’, ‘Sadanunia’, ‘Chakhao’ etc. were identified as promising genotypes in terms of different nutritional attributes. These cultivars were screened further for resistance against blast disease in field trials and cultivars like ‘Sadanunia’, ‘T4M-3-5’, ‘Chakhao Sampark’ were found to be highly resistant to the blast disease whereas ‘Kalonunia’, ‘Gobindabhog’, ‘Konkanijoha’ were found to be highly susceptible. Principal Component analysis divided the genotypes in distinct groups for nutritional potential and blast tolerance. The resistant and susceptible genotypes were screened for the presence of the blast resistant pi genes and association analysis was performed with disease tolerance. Finally, a logistic model based on phenotypic traits for prediction of the blast susceptibility of the genotypes is proposed with more than 80% accuracy.

scholarly journals Codon usage bias and environmental adaptation in microbial organisms

2021 ◽  
Author(s):  
Davide Arella ◽  
Maddalena Dilucca ◽  
Andrea Giansanti
Keyword(s):  
Codon Usage ◽  
Codon Usage Bias ◽  
Pathogenic Bacteria ◽  
Large Scale ◽  
Synonymous Codon ◽  
Principal Component ◽  
Gene Copy ◽  
Phenotypic Traits ◽  
Translational Efficiency ◽  
Microbial Organisms

AbstractIn each genome, synonymous codons are used with different frequencies; this general phenomenon is known as codon usage bias. It has been previously recognised that codon usage bias could affect the cellular fitness and might be associated with the ecology of microbial organisms. In this exploratory study, we investigated the relationship between codon usage bias, lifestyles (thermophiles vs. mesophiles; pathogenic vs. non-pathogenic; halophilic vs. non-halophilic; aerobic vs. anaerobic and facultative) and habitats (aquatic, terrestrial, host-associated, specialised, multiple) of 615 microbial organisms (544 bacteria and 71 archaea). Principal component analysis revealed that species with given phenotypic traits and living in similar environmental conditions have similar codon preferences, as represented by the relative synonymous codon usage (RSCU) index, and similar spectra of tRNA availability, as gauged by the tRNA gene copy number (tGCN). Moreover, by measuring the average tRNA adaptation index (tAI) for each genome, an index that can be associated with translational efficiency, we observed that organisms able to live in multiple habitats, including facultative organisms, mesophiles and pathogenic bacteria, are characterised by a reduced translational efficiency, consistently with their need to adapt to different environments. Our results show that synonymous codon choices might be under strong translational selection, which modulates the choice of the codons to differently match tRNA availability, depending on the organism’s lifestyle needs. To our knowledge, this is the first large-scale study that examines the role of codon bias and translational efficiency in the adaptation of microbial organisms to the environment in which they live.

108 Attentional Control Deficits during Total Sleep Deprivation: Independence from Reduced Vigilant Attention

SLEEP ◽  
2021 ◽  
Vol 44 (Supplement_2) ◽  
pp. A44-A45
Author(s):  
Darian Lawrence-Sidebottom ◽  
John Hinson ◽  
Paul Whitney ◽  
Kimberly Honn ◽  
Hans Van Dongen
Keyword(s):  
Sleep Deprivation ◽  
Attentional Control ◽  
Phase 1 ◽  
Principal Component ◽  
Relative Accuracy ◽  
Target Pair ◽  
Continuous Performance Task ◽  
Total Sleep Deprivation ◽  
Recovery Sleep ◽  
Variance Explained

Abstract Introduction Total sleep deprivation (TSD) has been shown to impair performance on a two-phase attentional control task, the AX-type continuous performance task with switch (AX-CPTs). Here we investigate whether the observed AX-CPTs impairments are a downstream consequence of TSD-induced non-specific effects (e.g., reduced vigilant attention) or reflect a distinct impact on attentional control. Methods N=55 healthy adults (aged 26.0±0.7y; 32 women) participated in a 4-day laboratory study with 10h baseline sleep (22:00-08:00) followed by 38h TSD and then 10h recovery sleep. At baseline (09:00 day 2) and after 25h and 30h TSD (09:00 and 14:00 day 3), subjects were tested on a 10min psychomotor vigilance test (PVT), an assay of vigilant attention, and on the AX-CPTs. The AX-CPTs required subjects to differentiate designated target from non-target cue-probe pairs. In phase 1, target trials occurred frequently, which promoted prepotent anticipatory responses; in phase 2, the target pair was switched. Accuracy of responses to various different AX-CPTs trial types was expressed relative to accuracy on phase 1 neutral (non-target cue and probe) trials, which should capture non-specific impairments on the task. For all three test sessions, these relative accuracy measures, along with accuracy on phase 1 neutral trials and lapses (RT&gt;500ms) on the PVT, were subjected to principal component analysis (PCA). Results The PCA revealed three statistically independent factors. Following varimax rotation, factor 1 (36.3% variance explained) and factor 3 (14.8% variance explained) each had high loadings for relative accuracy on multiple AX-CPTs trial types from phases 1 and 2; whereas factor 2 (17.9% variance explained) had high loadings for accuracy on phase 1 neutral trials, relative accuracy on phase 1 target trials, and PVT lapses. Conclusion These results indicate a statistical separation between AX-CPTs phase 1 neutral trials and phase 1 target trials, in conjunction with PVT lapses, versus the various other AX-CPTs trial types. This suggests a dissociation between TSD-induced, non-specific impairments on the task—potentially related to reduced vigilant attention—and TSD-induced specific impairments related to attentional control. Thus, TSD-induced deficits in attentional control are unlikely to be a downstream consequence of non-specific impairments. Support (if any) CDMRP grant W81XWH-16-1-0319

scholarly journals Rhamnella intermedia (Rhamnaceae), a new evergreen species from southwest Guangxi

PhytoKeys ◽  
2020 ◽  
Vol 159 ◽  
pp. 115-126
Author(s):  
Zhiqiang Lu ◽  
Yongshuai Sun
Keyword(s):  
New Species ◽  
Related Species ◽  
Principal Component ◽  
Phenotypic Traits ◽  
Evergreen Species ◽  
Closely Related Species ◽  
Field Investigations ◽  
Sequence Variations ◽  
Dried Fruit ◽  
Nuclear Its

Rhamnella intermedia, a new evergreen species from southwest Guangxi, is described and illustrated in this study. This species is similar to R. brachycarpa by the size and ratio of length to width of dried fruit and seeds, by which it differs from R. rubrinervis and R. tonkinensis. However, it differs from R. brachycarpa by rarely mucronate seed apices, larger ratio of length to width of leaves, leaf apices acuminate to long acuminate, shorter leaf petioles, and longer fruiting pedicels. Principal component analysis based on phenotypic traits further recognised three separated groups. Rhamnella rubrinervis and R. tonkinensis were clustered into one group; the other two groups represented R. brachycarpa and two Guangxi populations, respectively. Furthermore, phylogenetic analysis of nuclear ITS sequence variations highly supported that the two Guangxi populations represented an independent evolutionary lineage and were closest to R. rubrinervis. Four fixed nucleotide sites were found and were different from R. rubrinervis. However, besides the differentiated traits in seeds and fruit, densely pilose young branches also separated them from R. rubrinervis. In addition, during our field investigations, none of the three closely related species were found at locations where this new species was distributed. Therefore, this new species, based on the two Guangxi populations, is named R. intermedia. The key to four closely related species is also presented.

scholarly journals Genetic variation for seed yield components of Westerwold ryegrass (Lolium multiflorum var. westerwoldicum).

1989 ◽  
Vol 37 (2) ◽  
pp. 119-127 ◽  
Author(s):  
A. Elgersma ◽  
A.P.M. Den Nijs ◽  
F.A. Van Eeuwijk
Keyword(s):  
Genetic Variation ◽  
Seed Yield ◽  
Yield Components ◽  
Lolium Multiflorum ◽  
Genotypic Variation ◽  
Yield Component ◽  
Path Analyses ◽  
Seed Yield Components ◽  
High Heritability ◽  
1000 Grain Weight

Genetic variation for seed yield components was studied in 4 diploid varieties of Westerwold ryegrass, and 19 genotypes from each variety were grown in the field in 2 clonal replicate rows (minirows). The number of inflorescences/minirow, the numbers of spikelets/inflorescence and florets and seeds/spikelet, 1000-grain weight and seed yield/minirow were determined. Floret site utilization (FSU) was calculated as (seeds/floret) x 100%. Genotypic variation and heritabilities were calculated. Correlation studies and path analyses were carried out in each variety separately. Among varieties, no significant differences occurred for seed yield. However, within varieties large genetic variation was present for both seed yield and yield components. Path analyses revealed that relationships between seed yield components differed to a great extent among varieties. FSU was the major yield component in 3 varieties, but in one variety inflorescence number was the most important yield component. There was ample scope for genetic improvement of seed yield. FSU had a very high heritability and was not correlated with any of the other seed yield components. (Abstract retrieved from CAB Abstracts by CABI’s permission)

scholarly journals Genetic diversity of common bean (Phaseolus vulgaris L.) breeding collection in Serbia

Genetika ◽  
2019 ◽  
Vol 51 (1) ◽  
pp. 1-15 ◽  
Author(s):  
Aleksandra Savic ◽  
Milka Brdar-Jokanovic ◽  
Miodrag Dimitrijevic ◽  
Sofija Petrovic ◽  
Milan Zdravkovic ◽  
...  
Keyword(s):  
Common Bean ◽  
Gene Pool ◽  
Gene Diversity ◽  
Principal Component ◽  
Molecular Data ◽  
Phenotypic Traits ◽  
Gene Pools ◽  
Vegetable Crops ◽  
Novi Sad

The characterization of 41 common bean cultivars and landraces from breeding collection of Institute of Field and Vegetable Crops, Novi Sad, Serbia, was done based on phenotypic traits and microsatellite markers. Phenotypic traits were chosen from Bioversity International descriptor list. In addition, main yield components were investigated. Analysis of phaseolin type revealed affiliation of cultivars and landraces to Mesoamerican or Andean gene pool. Cultivars and landraces demonstrated significant diversity level with regard to studied phenotypic traits. Identified variation showed high potential for developing new cultivars with desirable combination of traits. Principal component analysis based on phenotypic traits separated bean cultivars and landraces in two groups, which corresponded to Mesoamerican and Andean determined according to phaseolin type. Putative hybrids, with combination of traits between gene pools were also identified. Analysis of microsatellite data, using twenty-two SSR primer pairs, showed medium gene diversity in studied material. Microsatellite-based cluster analysis separated genotypes in two discrete clusters and several subclusters. No clear separation according to gene pool was found between the clusters, however grouping according to gene pool and patterns of phenotypic variation, following these gene pools, were observed within subclusters. Knowledge on detailed relationships of cultivars and landraces based on phenotypic and molecular data would facilitate identification of candidates for future breeding.

scholarly journals Financial contagion and 2016 oil crisis: a factor analysis

2020 ◽  
Author(s):  
Turki Maya
Keyword(s):  
Stock Market ◽  
Stock Markets ◽  
Principal Component ◽  
Financial Contagion ◽  
Market Returns ◽  
Component Structure ◽  
Stock Market Returns ◽  
Oil Crisis ◽  
Market Indexes ◽  
Variance Explained

<p>The paper tries to answer the following question: could the 2016 oil price crisis generate financial contagion among stock markets? </p> <p>The study period is composed of two sub-periods; a quiet one from 3/01/2012 to 01/08/2014 and turbulent one from 04/08/2014 to 25/05/2016. Raw data consists of daily international stock market indexes prices. The co-movements of the stock market returns are analyzed through a principal component analysis (PCA).</p> <p>The results revealed that the <em>KMO</em> index (Kaiser-Mayer-Olkin) is higher during the turbulent period than during the quiet one and that the proportion of variance explained by the first component during the turbulent period reached 35% while during the quiet one it represented only 26,7%.Regarding the component structure, for the turbulent period, three factors are able to explain the stock markets indexes movements while for the quiet period four factors are required. </p> <p>The findings give more credit to the thesis supporting the linkage between cross correlation and financial contagion and classify the 2016 oil crisis, as just a coupling episode and not an extreme one.</p>

scholarly journals Variation of Phenotypic Traits in Twelve Bambara Groundnut (Vigna subterranea (L.) Verdc.) Genotypes and Two F2 Bi-Parental Segregating Populations

Agronomy ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1451
Author(s):  
Xiuqing Gao ◽  
Aliyu Siise Abdullah Bamba ◽  
Aloyce Callist Kundy ◽  
Kumbirai Ivyne Mateva ◽  
Hui Hui Chai ◽  
...  
Keyword(s):  
Southern Africa ◽  
Negative Relationship ◽  
Principal Component ◽  
Bambara Groundnut ◽  
Structured Populations ◽  
Phenotypic Trait ◽  
Phenotypic Traits ◽  
Potential Contribution ◽  
Vigna Subterranea ◽  
East West

Underutilised species such as bambara groundnut (Vigna subterranea (L.) Verdc.) have the potential to contribute significantly to meeting food and nutritional needs worldwide. We evaluated phenotypic traits in twelve bambara groundnut genotypes from East, West and Southern Africa and Southeast Asia and two F2 bi-parental segregating populations derived from IITA-686 ×Tiga Nicuru and S19-3 ×DodR to determine phenotypic trait variation and their potential contribution to the development of improved crop varieties. All phenotypic traits in twelve genotypes were significantly influenced (p < 0.01) by genotypes. Principal component analysis (PCA) showed that PC1 accounted for 97.33% variation and was associated with four genotypes collected from East and Southern Africa. PC2 accounted for 2.48% of the variation and was associated with five genotypes collected from East, West and Southern Africa. Transgressive segregation for a number of traits was observed in the two F2 bi-parental populations, as some individual lines in the segregating populations showed trait values greater or less than their parents. The variability between twelve genotypes and the two F2 bi-parental segregating populations and the negative relationship between plant architectural traits and yield related traits provide resources for development of structured populations and breeding lines for bambara groundnut breeding programme.

Genotypic variation for seed yield components in white clover (Trifolium repens L.)

2000 ◽  
Vol 51 (6) ◽  
pp. 657 ◽  
Author(s):  
M. Z. Z. Jahufer ◽  
F. I. Gawler
Keyword(s):  
Seed Yield ◽  
White Clover ◽  
Yield Components ◽  
Early Stage ◽  
Genotypic Variation ◽  
Principal Component ◽  
Positive Association ◽  
Genotypic Correlation ◽  
Yield Attributes ◽  
Seed Yield Components

Seed yield is an important criterion that determines the commercial acceptability of new cultivars. Often, the seed yielding capacity of a forage cultivar is tested only in the final stages of its development. A more efficient strategy would be to screen and select plants for seed yield at an early stage of breeding. An important objective of the National White Clover Breeding Program based at the Agriculture Victoria Pastoral and Veterinary Institute, Hamilton, is to assess the genetic diversity for important morphological attributes among germplasm accessions. A set of 53 accessions, which included germplasm collected from Morocco and Tunisia and a range of commercial cultivars, was characterised for seed yield components. The seed yield components were number of ripe inflorescences, number of florets per ripe inflorescence, number of seeds per pod, floret size, and inflorescence height. Potential seed yield was estimated. The magnitude of genotypic variation, together with the accession mean repeatability estimates, indicated the presence of genetic variation among the 53 accessions for all attributes. Both phenotypic and genotypic correlation coefficients indicated a strong positive association between total number of ripe inflorescences and seed yield. There was also a positive phenotypic and genotypic correlation between seed yield and number of florets per inflorescence. Cluster analysis of the 53 accessions based on seed yield components resulted in the generation of 6 groups. Principal component analysis helped to identify 5 accessions that could be potentially useful in improving the seed yield of white clover germplasm selected for superior agronomic and herbage yield attributes.

scholarly journals Comprehensive phenotypic and statistical based analysis of foxtail millet (Setaria italic L.) lines for parental line selection

2017 ◽  
Vol 6 (11) ◽  
pp. 1736 ◽  
Author(s):  
Chandra Sekhar Akila ◽  
Palakurthi Ramesh ◽  
Gurulakshmi Kola ◽  
Mallikarjuna Gunti ◽  
Puli Chandra Obul Reddy ◽  
...  
Keyword(s):  
Phenotypic Variability ◽  
Foxtail Millet ◽  
Principal Component ◽  
Breeding Systems ◽  
Phenotypic Traits ◽  
Parental Line ◽  
Panicle Length ◽  
Pure Lines ◽  
Total Seed ◽  
Panicle Weight

Minor millets are the small-grained cereals that belong to family Poaceae, with local importance as a food source but are often called as underutilized plant species.   Foxtail millet is one among  the oldest cultivated small diploid, C4 Panicoid, with short life cycle, and inbreeding nature. The genetic diversity of the foxtail millet is important for breeding systems, geographical distribution studies, assist in conservation of genetic resources for high yielding varietal development in breeding programs, expansion of the genetic base and for identification of genes for various phenotypic traits. Keeping in view of this an attempt has made to develop pure lines from local farmers preserved populations and phenotypically characterize them along with four released cultivars.  A total of eleven farmers varieties and four released cultivars were evaluated for seven quantitative traits in complete random block desing at net house conditions.  The maximum coefficient of variation was observed for panicle exertion, followed by number of tillers/plant and panicle weight. High positive significant correlations was observed for Plant height, panicle length, panicle weight and total seed weight with other traits under study. Panicle exertion exhibit negative correlations with panicle length, panicle weight and no of tillers. The results of principal component analysis (PCA) explains variability of 95.43% in the fifteen genotypes for the traits under study that corresponds to first 4 eigen values with greater than 0.60.  The proportions of the total variance explained by the first 4 principal components (PCs) were 42.98%, 71.02%, 85.43% and 95.43% respectively. Wards method based genetic similarity or dissimilarity clustering based on seven morphological traits among the fifteen foxtail millet genotypes was able to separate and grouped them into 2 major clusters I and II.  The genetic and phenotypic variability present in the foxtail millet genotypes give opportunity for plant breeders for effective selection of specific donor lines for foxtail millet improvement.

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