Sweet potato (Ipomoea batatas L. Lam) is a dicotyledonous tuber crop belonging to the morning glory family, Convolvulaceae. It is one of the staple foods because it is easy to propagate and maintain, and yield well under a variety of adverse conditions. Constructing genetic maps in polyploids has historically been challenging, and has most successfully been accomplished for allopolyploid species. In this study, the parental analysis with 90 SSR primer pairs identified 43.3 per cent polymorphism. The polymorphic SSR primer pairs were used for genotyping the F1 mapping population and their segregation among mapping population produced 138 segregating loci using SDRF method. From the segregating loci, 69 SSR loci were found to be linked into six different linkage groups and the rest of 69 SSR loci remained unlinked. These segregating markers were used for linkage map construction and the markers were randomly distributed onto the six linkage groups with a total length of 1957.1 cM and the average marker interval of 133.44 cM. Single marker analysis (SMA) was carried out by one-way ANOVA using the phenotypic and genotypic data segregated in the F1 progenies. The SMA between marker and phenotype resulted in the identification of sixteen SSR marker alleles having association with the β-carotene. SSR markers associated with QTLs related to β-carotene, dry matter and starch content were identified by single marker analysis (SMA), simple interval mapping (SIM) and composite interval mapping (CIM) using Windows QTL Cartographer.

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