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DNA markers have broad applications, including marker-assisted selection (MAS) for breeding new cultivars. Currently, single nucleotide polymorphisms (SNPs) have become a preferred choice of markers for molecular geneticists and breeders. They offer many advantages, such as high abundance and coverage in the genome, codominant inheritance, locus specificity, and flexibility for high-throughput genotyping/detection formats, and they are relatively inexpensive. The availability of reference genome sequences enables precise identification of candidate genes and SNPs associated with a trait of interest through quantitative trait loci mapping and genome-wide association studies. Such SNPs can be converted into markers for their application in MAS in crop breeding programs. Cleaved amplified polymorphic sequence (CAPS) markers amplify short genomic sequences around the polymorphic endonuclease restriction site. This review provides insight into the recent advancements made in the development and application of CAPS markers in several horticultural plants. We discussed many new tools that aid faster and more accurate design of CAPS markers from the whole genome resequencing data. The developed CAPS markers offer immense application in germplasm screening and field trials, genomic loci mapping, identifying candidate genes, and MAS of important horticultural traits such as disease resistance, fruit quality and morphology, and genetic purity. [ABSTRACT FROM AUTHOR]

Blueberry (Vaccinium spp.) is one of the most economically important berry crops worldwide. Validation of genetic mapping studies is often hindered by asynchronous marker technology. The development of a standardized genotyping platform that targets a specific set of polymorphic loci can be a practical solution to unify the scientific and breeding community toward blueberry improvement. The objective of this study was to develop and evaluate a targeted genotyping platform for cultivated blueberries that is affordable, reproducible, and sufficiently high density to warrant large-scale adoption for genomic studies. The Flex-Seq platform was developed in a two-step procedure that resulted in 22,000 loci that yielded 194,365 single nucleotide polymorphisms when assessed in a diversity set of 192 samples including cultivated and other related wild Vaccinium species. Locus recovery averaged 89.4% in the cultivated polyploid blueberry (northern highbush [NHB], southern highbush [SHB], and rabbiteye [RE]) and on average 88.8% were polymorphic. While recovery of these loci was lower in the other Vacciniumspecies assayed, recovery remained high and ranged between 60.8% and 70.4% depending on the taxonomic distance to the cultivated blueberry targeted in this platform. NHB had the highest mean number of variants per locus at 9.7, followed by RE with 9.1, SHB with 8.5, and a range between 7.7 and 8.5 in other species. As expected, the total number of unique-instate haplotypes exceeded the total number of variants in the domesticated blueberries. Phylogenetic analysis using a subset of the SNPs and haplotypes mostly conformed to known relationships. The platform also offers flexibility about the number of loci, depth of sequencing for accurate dosage calling, loci and haplotype reconstruction from increased fragment length. This genotyping platform will accelerate the development and improvement of blueberry cultivars through genomic-assisted breeding tools. [ABSTRACT FROM AUTHOR]