107 research outputs found
The attitudes of students of psychology in grading knowledge and creativity
Starting from Gilford’s differentiation of thinking into convergent and divergent, research was carried out into the attitudes of the students of psychology towards quality and the objectivity of professor’s gradings, representation of certain elements of grading, as well as the ways of forming the final grade on an exa
Molecular characterization of old local grapevine varieties from South East European countries
South East European (SEE) viticulture partially relies on native grapevine varieties, previously scarcely described. In order to characterize old local grapevine varieties and assess the level of synonymy and genetic diversity from SEE countries, we described and genotyped 122 accessions from Albania, Federation of Bosnia and Herzegovina (B&H), Croatia, Macedonia, Moldova, Montenegro, Republika Srpska (Bosnia and Herzegovina) and Romania on nine most commonly used microsatellite loci. As a result of the study a total of 86 different genotypes were identified. All loci were very polymorphic and a total of 96 alleles were detected, ranging from 8 to 14 alleles per locus, with an average allele number of 10.67. Overall observed heterozygosity was 0.759 and slightly lower than expected (0.789) while gene diversity per locus varied between 0.600 (VVMD27) and 0.906 (VVMD28). Eleven cases of synonymy and three of homonymy have been recorded for samples harvested from different countries. Cultivars with identical genotypes were mostly detected between neighboring countries. No clear differentiation between countries was detected although several specific alleles were detected. The integration of the obtained genetic data with ampelographic ones is very important for accurate identification of the SEE cultivars and provides a significant tool in cultivar preservation and utilization.
Population structure and genetic diversity in a commercial maize breeding program assessed with SSR and SNP markers
Information about the genetic diversity and population structure in elite breeding material is of fundamental importance for the improvement of crops. The objectives of our study were to (a) examine the population structure and the genetic diversity in elite maize germplasm based on simple sequence repeat (SSR) markers, (b) compare these results with those obtained from single nucleotide polymorphism (SNP) markers, and (c) compare the coancestry coefficient calculated from pedigree records with genetic distance estimates calculated from SSR and SNP markers. Our study was based on 1,537 elite maize inbred lines genotyped with 359 SSR and 8,244 SNP markers. The average number of alleles per locus, of group specific alleles, and the gene diversity (D) were higher for SSRs than for SNPs. Modified Roger’s distance (MRD) estimates and membership probabilities of the STRUCTURE matrices were higher for SSR than for SNP markers but the germplasm organization in four heterotic pools was consistent with STRUCTURE results based on SSRs and SNPs. MRD estimates calculated for the two marker systems were highly correlated (0.87). Our results suggested that the same conclusions regarding the structure and the diversity of heterotic pools could be drawn from both markers types. Furthermore, although our results suggested that the ratio of the number of SSRs and SNPs required to obtain MRD or D estimates with similar precision is not constant across the various precision levels, we propose that between 7 and 11 times more SNPs than SSRs should be used for analyzing population structure and genetic diversity
The European Vitis Database (www.eu-vitis.de) – a technical innovation through an online uploading and interactive modification system
The objective of the European Vitis Database is to safeguard and enhance germplasm by monitoring its preservation. Two issues are strongly related to that purpose: (1) participation of collections covering almost all grape biodiversity and (2) assessment of accessions trueness to type. In the scope of the European project GrapeGen06 efforts have been made towards both objectives. The 35 participating grape germplasm repositories are found between the Iberian Peninsula and Transcaucasia, thus covering a broad range of grape diversity. Altogether they maintain 32,410 accessions. However with respect to biodiversity, gaps are still evident and further collections need to be included and trueness to type assessment absolutely needs to be pursued to organize duplication of endangered genotypes. Within the GrapeGen06 project focus was laid on the establishment of a database conferring the collection holders a high degree of responsibility and independence. Hence for the first time in a European Central Crop Database an on-line uploading application and an interactive modification system for data administration was implemented. These innovations disburden the database manager and offer the curators of collections more flexibility. Prerequisites for data import, descriptors applied, access levels, database contents, uploading, export and search functions are described
Genetic diversity in cultivated carioca common beans based on molecular marker analysis
A wide array of molecular markers has been used to investigate the genetic diversity among common bean species. However, the best combination of markers for studying such diversity among common bean cultivars has yet to be determined. Few reports have examined the genetic diversity of the carioca bean, commercially one of the most important common beans in Brazil. In this study, we examined the usefulness of two molecular marker systems (simple sequence repeats – SSRs and amplified fragment length polymorphisms – AFLPs) for assessing the genetic diversity of carioca beans. The amount of information provided by Roger’s modified genetic distance was used to analyze SSR data and Jaccards similarity coefficient was used for AFLP data. Seventy SSRs were polymorphic and 20 AFLP primer combinations produced 635 polymorphic bands. Molecular analysis showed that carioca genotypes were quite diverse. AFLPs revealed greater genetic differentiation and variation within the carioca genotypes (Gst = 98% and Fst = 0.83, respectively) than SSRs and provided better resolution for clustering the carioca genotypes. SSRs and AFLPs were both suitable for assessing the genetic diversity of Brazilian carioca genotypes since the number of markers used in each system provided a low coefficient of variation. However, fingerprint profiles were generated faster with AFLPs, making them a better choice for assessing genetic diversity in the carioca germplasm
Lipid and lipoprotein responses of dyslipidemic patients to exclusive nutritional counseling by gender and age
Multiple origins of cultivated grapevine (Vitis vinifera L. ssp. sativa) based on chloroplast DNA polymorphisms
- …