Characterization of Ugandan Sweetpotato Germplasm Using Fluorescent Labeled Simple Sequence Repeat Markers (original) (raw)
Related papers
Dna Sequence Polymorphism Based Genetic Diversity Studies in Sweetpotato Germplasm
HortScience
Highly polymorphic DNA markers were identified in sweetpotato (Ipomoea batatas) using PCR amplification and arbitrary primers. More than 100 accessions representing US cultivars and their progenitors, and germplasm lines from around the world were analyzed. Sweetpotato germplasm exhibited high genetic variability and individual-specific profiles were obtained for all accessions. US cultivars formed a tight cluster in the principal coordinate analysis suggesting a narrow genetic base. The genetic relationship data of US cultivars and their progenitors based on DNA polymorphisms was in agreement with their known pedigree. The putative paternal parents of certain cultivars selected through open pollination were identified based on shared polymorphisms. The PCR-based markers are valuable in the characterization of sweetpotato germplasm and in ensuring a broad genetic base for future cultivars.
Selection of Sweetpotato Parental Genotypes Using Simple Sequence Repeat Markers
Plants
Knowledge of the genetic diversity and genetic relationship is important in crop improvement. The objective of this study was to determine the genetic diversity of 31 sweetpotato genotypes and furthermore to select distantly related individuals for breeding of superior parental clones. The genotypes (sourced from the Agricultural Research Council, South Africa) originating from Africa and American continent were genotyped using eight highly polymorphic SSR markers. The SSR markers generated a total of 83 putative alleles. The polymorphic information content (PIC) of the tested simple sequence markers varied from 0.73 to 0.91, with a mean of 0.85. At least 11 different alleles were found in 8 loci within the population, with 7 effective alleles per locus. Although high diversity was found among the genotypes, genetic distances among the genotypes were relatively low. Cluster analysis revealed the existence of three distinct genetic groups, and the clustering patterns follow to some e...
Crop Science, 2011
Sweetpotato [Ipomoea batatas (L.) Lam] farmer varieties are still the backbone of production and breeding programs in Sub-Sahara Africa. Usually, farmer varieties in Sub-Sahara Africa are white-or cream-fleshed sweetpotato (WFSP), but recently orange-fleshed sweetpotato (OFSP) were found in East Africa. The objective of the study was to characterize WFSP and OFSP germplasm from East Africa. Eighty-five East African farmer varieties (29 OFSPs and 56 WFSPs) and seven varieties of non-African origin as check clones were analyzed for diversity using 26 simple sequence repeat (SSR) markers. A total of 158 alíeles were scored with an average of 6.1 alíeles per SSR loci. The mean of Jaccard's similarity coefficients was 0.54. The unweighted pair group method analysis (UPGMA) revealed a main cluster for East Africa germplasm at a similarity coefficient of 0.52. At a similarity coefficient of about 0.55 subclusters within the East African germplasm were observed, but these were neither country nor flesh color specific. Analysis of molecular variance (AMOVA) found a significant difference between East African and non-African germplasm and a nonsignificant difference between OFSP and WFSP germplasm. In conclusion, the East African germplasm appears to be distinct from non-African germplasm, and OFSP and WFSP farmer varieties from East Africa are closely related. Orange-fleshed sweetpotato farmer varieties from East Africa might show similar adaptation to Sub-Sahara African environments as WFSP and a big potential in alleviating vitamin A deficiency.
HortScience
Fifteen sweetpotato [Ipomoea batatas (L.) Lam] accessions grown on Guam were studied for morphological and genetic characteristics. Accessions, obtained from AVRDC (Asian Vegetable Research and Development Center) in Taiwan, Saipan, Rota, and Guam, were investigated for marketable yield, growth habit and characteristics of tuberous roots (color, shape, sugar content and moisture content). Results of this study were used to determine the morphological relationship of the accessions of sweetpotato. Phenetic analysis revealed four major clusters according to tuberous root characteristics. The genetic relationship of these sweetpotato accessions was also evaluated for genetic differences among accessions. DNA was extracted and went through polymerase chain reaction (PCR). PCR products were analyzed by random amplified polymorphic DNA (RAPD) fingerprinting. Result of the genetic relationship among the sweetpotatoes was compared with the morphology of accessions using UPGMA cluster analys...
Genetic Resources and Crop Evolution, 2014
Knowledge about the genetic diversity and structure of crop cultivars can help make better conservation decisions, and guide crop improvement efforts. Diversity analysis using microsatellite markers was performed to assess the level of genetic diversity in sweet potato in Uganda, and evaluate the genetic relationship between the Uganda's germplasm and some genotypes obtained from Kenya, Tanzania, Ghana, Brazil and Peru. A total of 260 sweet potato cultivars were characterized using 93 microsatellite loci. The Ugandan collection showed a large number of distinct landraces, and very low (3 %) levels of genetic diversity between genotypes obtained from the different agro-ecological zones. There was low (6 %) levels of genetic diversity observed between the East African genotypes; however unique alleles were present in collections from the various sources. Pairwise comparisons of genetic differentiation indicated that Uganda's germplasm was significantly different (P \ 0.001) from cultivars from Tanzania, Ghana, Brazil and Peru. The presence of unique alleles in populations from various Uganda's agro-ecological zones and other global regions, as well as the regional diversity patterns, suggest that efforts should be made to further collect and characterize the germplasm in more depth.
Hortscience, 2015
Genetic diversity is critical in sweetpotato improvement as it is the source of genes for desired genetic gains. Knowledge of the level of genetic diversity in a segregating family contributes to our understanding of the genetic diversity present in crosses and helps breeders to make selections for population improvement and cultivar release. Simple sequence repeat (SSR) markers have become widely used markers for diversity and linkage analysis in plants. In this study, we screened 405 sweetpotato SSR markers for polymorphism on the parents and progeny of a biparental cross of New Kawogo 3 Beauregard cultivars. Thereafter, we used the informative markers to analyze the diversity in this population. A total of 250 markers were polymorphic on the parents and selected progeny; of these, 133 were informative and used for diversity analysis. The polymorphic information content (PIC) values of the 133 markers ranged from 0.1 to 0.9 with an average of 0.7, an indication of high level of informativeness. The pairwise genetic distances among the progeny and parents ranged from 0.2 to 0.9, and they were grouped into five main clusters. The 133 SSR primers were informative and are recommended for use in sweetpotato diversity and linkage analysis.