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Germplasm evaluation, classification, characterization, and preservation are the initial requirements for any crop genetic improvement programs meant to promote economically important traits. Mean performance and range of different expressible traits through ANOVA showed highly significant differences within the various genotypes and helped to evaluate several promising carrot genotypes. The multivariate analysis method was used in this study, which was helpful in resolving different phenotypic and genotypic parameters/measurements of big collections into easy interpretable dimensions.The research work was carried out with eighty-one genotypes to evaluate genetic diversity in a germplasm collection through multivariate analysis.The divergence analysis grouped all eighty-one genotypes into ten clusters and cluster VI was found to be the biggest, comprised of 30 genotypes, followed by IV, which was comprised of 16 genotypes. Cluster X exhibited a high mean value for root weight and anthocyanin content; cluster III showed high value for days to 1st root harvest and root girth, and cluster V for dry matter content, total sugar content, and carotene content; respectively. The maximum distance between clusters was recorded among II and X cluster (43,678.5) follow by I and X (43,199.7), and it indicated that genotypes from these far away clusters could be used efficiently in breeding programs to obtain superior hybrids. Total sugar content (36.14%) contributed most to genetic divergence, followed by anthocyanin content (35.74%). Out of four principal components, PC1 largely contributed towards total variation, followed by PC2. The partial variances (%) from the first to fourth PC-axes were 36.77, 25.50, 12.67, and 10.17, respectively. Genotypes like PC-161, PC-173, PAU-J-15, PC-103, and PC-43 were considered superior with respect to marketable yield and its associated traits such as root length and root weight, and hence can be released directly as a variety. [ABSTRACT FROM AUTHOR]

Knowledge of the natural patterns of genetic variation and their evolutionary basis is required for sustainable management and conservation of wheat germplasm. In the current study, the genetic diversity and population structure of 100 individuals from four Triticum and Aegilops species (including T. aestivum, Ae. tauschii, Ae. cylindrica, and Ae. crassa) were investigated using two gene-based markers (start codon targeted (SCoT) polymorphism and CAAT-box derived polymorphism (CBDP)) and simple-sequence repeats (SSRs). The SCoT, CBDP, and SSR markers yielded 76, 116, and 48 polymorphism fragments, respectively. The CBDP marker had greater efficiency than the SCoT and SSR markers due to its higher polymorphism content information (PIC), resolving power (Rp), and marker index (MI). Based on an analysis of molecular variance (AMOVA) performed using all marker systems and combined data, there was a higher distribution of genetic variation within species than among them. Ae. cylindrica and Ae. tauschii had the highest values for all genetic variation parameters. A cluster analysis using each marker system and combined data showed that the SSR marker had greater efficiency in grouping of tested accessions, such that the results of principal coordinate analysis (PCoA) and population structure confirmed the obtained clustering patterns. Hence, combining the SCoT and CBDP markers with polymorphic SSR markers may be useful in genetic fingerprinting and fine mapping and for association analysis in wheat and its germplasm for various agronomic traits or tolerance mechanisms to environmental stresses. [ABSTRACT FROM AUTHOR]

Among cereal crops, wheat has been identified as a major source for human food consumption. Wheat breeders require access to new genetic diversity resources to satisfy the demands of a growing human population for more food with a high quality that can be produced in variable environmental conditions. The close relatives of domesticated wheats represent an ideal gene pool for the use of breeders. The genera Aegilops and Triticum are known as the main gene pool of domesticated wheat, including numerous species with different and interesting genomic constitutions. According to the literature, each wild relative harbors useful alleles which can induce resistance to various environmental stresses. Furthermore, progress in genetic and biotechnology sciences has provided accurate information regarding the phylogenetic relationships among species, which consequently opened avenues to reconsider the potential of each wild relative and to provide a context for how we can employ them in future breeding programs. In the present review, we have sought to represent the level of genetic diversity among the wild relatives of wheat, as well as the breeding potential of each wild species that can be used in wheat-breeding programs. [ABSTRACT FROM AUTHOR]