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Genetic studies of new grains improved with quality traits
Full text linkIn a global context increasingly focused on sustainability and food quality, the search for sustainable and nutrient-rich raw materials is gaining growing interest. In cereal cultivation, worldwide researchers are shifting their focus to ancient cereals and wild species of domesticated crops. Among these, Aegilops caudata, a wild species, represents a promising genetic resource due to its nutritional characteristics that make it valuable for wheat improvement. Specifically, Aegilops caudata has been used to create amphiploid lines useful for studying qualitative traits such as β-glucan content, a key compounds for human health. Chapter I of this thesis analyzes a key gene in β-glucan synthesis, the cellulose synthase CslF6 gene, by determining the gene sequence and protein structure in Ae. caudata, highlighting evolutionary differences compared to other grass species and examining how variations in the amino acid sequence may influence the β-glucan content. Comparative analysis with other monocots revealed significant similarities with the wheat genome, with variations in amino acid motifs within the catalytic portions of the polypeptide chain, suggesting potential unique functional adaptations for Ae. caudata.
Chapter II explores the role of the CslF6 gene in β-glucan synthesis, the total β-glucan content, the glycosidic linkages within the β-glucan structure, and the profile of major oligosaccharides in bread and durum wheat genotypes, wild parental species (Aegilops caudata and Dasypyrum villosum), and their hybrids. The analysis of CslF6 gene expression revealed a correlation between gene expression and β-glucan accumulation. The results indicate that wild species, such as Ae. caudata and Dasypyrum villosum, have a higher β-glucan content compared to wheat, and hybrids show a significant increase in β-glucan levels. Additionally, through glycomics analysis, the study highlighted differences in the monosaccharide composition of the cell wall and the glycosidic linkages in the analyzed genotypes, providing new tools for the selection of wheat lines with high β-glucan content.
Chapter III shifts the focus on two important wheat qualitative traits: protein content (GPC) and yellow index (YI), which are critical for pasta production. The study, conducted on 144 tetraploid wheat accessions (Triticum turgidum L.), identified superior alleles associated with these qualitative traits through a Genome-Wide Association Study (GWAS). The analysis identified several association regions (QTLs) between SNP markers and the traits considered (GPC and YI). Bioinformatics analysis revealed candidate gene sequences co-localized within these QTL regions. Notably, a key gene involved in nitrogen metabolism, Glutamine synthetase 2 (GS2), and a key gene for carotenoid biosynthesis, Phytoene synthase 1 (Psy-A1), were identified. Furthermore, the analysis led to the identification of new haplotypes, contributing to a better understanding of the genetic mechanisms controlling protein content and yellow color in wheat, facilitating the development of superior wheat varieties.
These three studies, while addressing different aspects of wheat genetics and its wild relatives, are interconnected within a research framework aimed at improving the nutritional and qualitative traits of wheat. The exploration of the CslF6 gene and its role in β-glucan biosynthesis, alongside the characterization of qualitative traits such as protein content and yellow index, contributes to a deeper understanding of the genetic potential of wheat species, particularly those from wild genotypes such as Ae. caudata. The information obtained from this research offers new opportunities for the selection and development of more nutritious, sustainable, and consumer-oriented wheat varieties worldwide
Effect of mineral and organic fertilization on desi and kabuli chickpea (Cicer arietinum l.): Plant growth and production, hydration properties, bioactive compounds, and antioxidant activity
Full text linkComposting is a strategic technology to convert organic waste into environmentally friendly soil improvers, mitigating the pressure on landfills and contributing to sustainability. This research evaluates the effects of different doses of mineral/organic fertilizers on two chickpea types: desi and kabuli. A randomized block design with three replications and six conditions was adopted: non-fertilized control, two mineral fertilizations (M1, M2), and three organic fertilizations (B1, B2, B3). M1 and B1 provided for comparable NPK amounts. Fertilization and variety significantly influenced plant growth and production, and seed hydration. Fertilization had a lower influence on bioactive compounds. The highest seed yields were obtained with M2 (30–40–100 kg ha−1 of N, P2O5, and K2O, respectively. An addition of 40 kg ha−1 of P2O5 (M1) had no effect on seed yield. B1 (10 Mg ha−1 of Bio Vegetal) and M1 led to the same yield, which did not increase using higher doses of green compost. Mineral and organic fertilizations favored hydration and swelling of chickpeas. Desi chickpea showed a significantly higher seed yield but a lower seed weight than kabuli. Organic fertilization, combined with the recovery of peculiar chickpeas, which are more productive and richer in bioactive compounds, promotes a more sustainable food system
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Maize Yield Response, Root Distribution and Soil Desiccation Crack Features as Affected by Row Spacing
Full text linkPlant density is among the most critical factors affecting plant yields and resource use efficiency since it drives the exploitation of the available resources per unit area, root distribution and soil water losses by direct evaporation from the soil. Consequently, in fine-textured soils, it can also affect the formation and development of desiccation cracks. The aim of this study, carried out on a sandy clay loam soil in a typical Mediterranean environment, was to investigate the effects of different row spacings of maize (Zea mais L.) on yield response, root distribution and the main features of desiccation cracks. The field experiment compared bare soil and soil cropped with maize using three plant densities (6, 4 and 3 plants m−2), obtained by keeping the number of plants in a row constant and varying the distance between the rows (0.5–0.75–1.0 m). The highest kernel yield (16.57 Mg ha−1) was obtained with the greatest planting density (6 plants m−2) with a row spacing of 0.5 m; significantly lower yields were recorded with spacings of 0.75 and 1 m, with a decrease of 8.09% and 18.24%, respectively. At the end of the growing season, soil moisture in the bare soil was on average 4% greater in comparison to the cropped soil and was also affected by row spacing, decreasing with the decrease in the inter-row distance. An inverse behaviour was observed between soil moisture and both root density and desiccation crack size. Root density decreased to the increase in soil depth and to the increase in distance from the row. The pluviometric regime occurred during the growing season (total rainfall of 343 mm)-resulted in the formation of cracks of reduced size and with an isotropic behaviour in the bare soil, whereas in the cultivated soil, the cracks were parallel to the maize rows and increased in size with decreasing inter-row distance. The total volume of the soil cracks reached a value of 135.65 m3 ha−1 in the soil cropped with a row distance of 0.5 m, and was about ten times greater in comparison to the bare soil and three times greater in comparison to a row spacing of 1 m. Such a volume would allow a recharge of 14 mm in the case of intense rainy events on soil characterised by low permeability
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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