Abstract Background China is the largest producer of sweet potato in the world, accounting for 57.0% of the global output. Germplasm resources are the basis for promoting innovations in the seed industry and ensuring food security. Individual and accurate identification of sweet potato germplasm is an important part of conservation and efficient utilization. Results In this study, nine pairs of simple sequence repeat molecular markers and 16 morphological markers were used to construct genetic fingerprints for sweet potato individual identification. Combined with basic information, typical phenotypic photographs, genotype peak graphs, and a two-dimensional code for detection and identification were generated. Finally, a genetic fingerprint database containing 1021 sweet potato germplasm resources in the “National Germplasm Guangzhou Sweet Potato Nursery Genebank in China” was constructed. Genetic diversity analysis of the 1021 sweet potato genotypes using the nine pairs of simple sequence repeat markers revealed a narrow genetic variation range of Chinese native sweet potato germplasm resources, and Chinese germplasm was close to that from Japan and the United States, far from that from the Philippines and Thailand, and the furthest from that from Peru. Sweet potato germplasm resources from Peru had the richest genetic diversity, supporting the view that Peru is the center of origin and domestication of sweet potato varieties. Conclusions Overall, this study provides scientific guidance for the conservation, identification, and utilization of sweet potato germplasm resources and offers a reference to facilitate the discovery of important genes to boost sweet potato breeding.

The experiment was conducted to ascertain the level of genetic diversity in sweet potato accessions using microsatellites. Thirty sweet potato accessions obtained from the International Potato Center (CIP), Kumasi, Ghana, Mozambique, and local germplasm of the National Root Crops Research Institute (NRCRI), Umudike, Abia State, Nigeria, as well as sweet potato vines from local farmers' fields in Jos, Plateau State, and Bauchi State, Nigeria, were analyzed for genetic diversity using five microsatellite markers. The results showed that the polymorphic SSR loci revealed diverse relationship among the sweet potato cultivars, which was grouped into four major clusters by unweighted pair group method analysis (UPGMA) method. Cluster analysis showed a Jaccard co-efficient ranging from 0.0 to 3.0 indicating high genetic diversity. The primers detected a total of 18 alleles and the number of alleles per locus was 4 for IBR-19, IBR-286, IBR-297 and 3 for IBR-16 and IBR-242 with an average of 3.67 alleles per locus. The polymorphic information content (PIC) of the markers varied from 0.35 to 0.72 with an average of 0.497. Marker IBR-19 revealed the highest PIC of 0.72, while marker IBR-297 had the lowest PIC of 0.35. Observed heterozygosity ranged from 0.32 to 0.89 with a mean of 0.675 across the five SSR loci. The results from the Analysis of molecular variance (AMOVA) which was used to quantify the diversity level and genetic relationship among the thirty sweet potato accessions indicated that a high diversity was mostly distributed within the populations for sweet potato accessions (75.12%) and (15.67%) among the populations.

Cultivated potato varieties are tetraploid and vegetatively propagated. Therefore genetic improvement for new traits is less effective through hybridization. The mutation is considered an alternative method for crop improvement of those varieties. This study aimed to evaluate the effects of gamma-ray irradiation on increasing genetic diversity among the somaclones and the changes in population structure. Forty-four somaclones were used as observed materials. The population was grown in a screen house using a completely randomized design with genotype (somaclone) as a single factor. Thirteen qualitatively and quantitatively morphological characters were observed. Six SSR markers were used for analyzing the population structure. The selection process was based on a weighting method divided into quartiles. Selected numbers were taken from quartile 3. Morphological analysis of stems and leaves resulted in five different somaclones, with significant differences in anthocyanin appearance and intensity of the green color of the leaflets. Diversity criteria based on quantitative characteristics showed a high level of diversity with a high heritability for tuber weight, length, and diameter and a moderate heritability for tuber number. Analyzing the population structure has offered insight into how gamma irradiation affected the somaclones. As a result of the selection, 12 somaclones met the requirements to serve as seed sources for field testing. It is expected that the results of this study will provide information about the diversity caused by gamma-ray irradiation treatment on potato somaclones and a method for improving the efficiency of the initial selection of potato populations.

Information about the morphological and genetic characteristics of sweet potato (Ipomoea batatas) is important in the variety development program. This experiment aimed to determine the diversity and genetic relationship of sweet potato accessions from NTT based on morphological character data. The research was carried out at Kendalpayak Research Station, Malang, East Java from April - September 2019. The materials used were seventy-one sweet potato germplasm from the ILETRI collection (collected from NTT). Each accession was planted on a 1 m × 5 m plot size, with a spacing of 100 × 20 cm (single row). Fertilization was carried out using a dose of “100 kg urea + 100 kg SP36 + 200 kg KCl ha-1”. The observed characters were the vines length, growth type, internode length, leaf length, leaf width, leaf size, leaf bone color, leaf shape, leaf characteristics, lobes number, lobe shape, mature leaf color, shoot color, pigmentation of petiole, young stems pigmentation (dominant and secondary color), young leaves feathers, tuber skin color, tuber flesh color, weight of canopy, number of tubers perplot, weight of tubers perplot, number and weight of tubers perplot. Cluster analysis was carried out using the Minitab 17 program. There was morphological diversity in seventy-one accessions of sweet potato germplasm from NTT. Principal component analysis resulted in seven main components with the proportion of diversity 76.3%. cluster analysis, seventy-one accessions of sweet potato germplasm were divided into fifteen accession groups on the basis of 80% degree. Characteristics of shoot color, mature leaf color, leaf size, petiole pigmentation, and leaf bone color contributed greatly to the total diversity.

International audience | The development of marker-assisted selection in the 1990s offered new possibilities to fasten potato breeding and make it more efficient. A turning point in molecular potato breeding was the release of the first potato reference genome in 2011. The aim of this chapter is to give a comprehensive overview of the progress made in potato genetic studies and molecular breeding since the publication of the first potato genome. With the continuous progress made in sequencing technologies, the number of potato genomic datasets made available to the scientific community is blooming, opening new possibilities for a better comprehension and an optimized utilization of the large potato genetic diversity. The development of high-throughput genotyping methods and of software and tools especially designed for autopolyploid species also led to an important leap forward in potato genetic studies. These important developments caused changes in the plant material used in potato genetic studies, allowing switching from less complex diploid biparental populations to tetraploid panels less distant from the breeding material. Finally, an overview of the recent advances made in marker-assisted selection for resistance to potato cyst nematodes, potato virus Y, wart disease, and late blight is given. For each of these economically important traits, the lastly developed diagnostic markers at hand for potato breeders are described

International audience | The development of marker-assisted selection in the 1990s offered new possibilities to fasten potato breeding and make it more efficient. A turning point in molecular potato breeding was the release of the first potato reference genome in 2011. The aim of this chapter is to give a comprehensive overview of the progress made in potato genetic studies and molecular breeding since the publication of the first potato genome. With the continuous progress made in sequencing technologies, the number of potato genomic datasets made available to the scientific community is blooming, opening new possibilities for a better comprehension and an optimized utilization of the large potato genetic diversity. The development of high-throughput genotyping methods and of software and tools especially designed for autopolyploid species also led to an important leap forward in potato genetic studies. These important developments caused changes in the plant material used in potato genetic studies, allowing switching from less complex diploid biparental populations to tetraploid panels less distant from the breeding material. Finally, an overview of the recent advances made in marker-assisted selection for resistance to potato cyst nematodes, potato virus Y, wart disease, and late blight is given. For each of these economically important traits, the lastly developed diagnostic markers at hand for potato breeders are described