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Data from: Genetic Diversity and Population Structure of the USDA Sweetpotato (Ipomoea batatas) Germplasm Collections Using GBSpoly

    Population structure and genetic diversity of 417 USDA sweetpotato (*Ipomoea batatas*) accessions originating from 8 broad geographical regions (Africa, Australia, Caribbean, Central America, Far East, North America, Pacific Islands, and South America) were determined using single nucleotide polymorphisms (SNPs) identified with a genotyping-by-sequencing (GBS) protocol, GBSpoly, optimized for highly heterozygous and polyploid species.

    Data from: Genetic Architecture of Resistance to Stripe Rust in a Global Winter Wheat Germplasm Collection

      Virulence shifts in populations of *Puccinia striiformis* f. sp. *tritici* (*Pst*), the causal pathogen of wheat stripe rust, are a major challenge to resistance breeding. The majority of known resistance genes are already ineffective against current races of *Pst*, necessitating the identification and introgression of new sources of resistance. Germplasm core collections that reflect the range of genetic and phenotypic diversity of crop species are ideal platforms for examining the genetic architecture of complex traits such as resistance to stripe rust. We report the results of genetic characterization and genome-wide association analysis (GWAS) for resistance to stripe rust in a core subset of 1175 accessions in the National Small Grains Collection (NSGC) winter wheat germplasm collection, based on genotyping with the wheat 9K single nucleotide polymorphism (SNP) iSelect assay and phenotyping of seedling and adult plants under natural disease epidemics in four environments.

      Data from: Geography of Genetic Structure in Barley Wild Relative Hordeum vulgare subsp. spontaneum in Jordan

        Informed collecting, conservation, monitoring and utilization of genetic diversity requires knowledge of the distribution and structure of the variation occurring in a species. *Hordeum vulgare* subsp. spontaneum (K. Koch) Thell., a primary wild relative of barley, is an important source of genetic diversity for barley improvement and co-occurs with the domesticate within the center of origin. We studied the current distribution of genetic diversity and population structure in *H. vulgare* subsp. spontaneum in Jordan and investigated whether it is correlated with either spatial or climatic variation inferred from publically available climate layers commonly used in conservation and ecogeographical studies. The genetic structure of 32 populations collected in 2012 was analyzed with 37 SSRs. Three distinct genetic clusters were identified. Populations were characterized by admixture and high allelic richness, and genetic diversity was concentrated in the northern part of the study area. Genetic structure, spatial location and climate were not correlated. This may point out a limitation in using large scale climatic data layers to predict genetic diversity, especially as it is applied to regional genetic resources collections in *H. vulgare* subsp. spontaneum.

        Environmental Association Analyses Identify Candidates for Abiotic Stress Tolerance in Glycine soja, the Wild Progenitor of Cultivated Soybeans

          The present study explores an ex situ conservation collection, the USDA germplasm collection, genotyped at 32,416 SNPs, to identify population structure and test for associations with bioclimatic and biophysical variables in Glycine soja, the wild progenitor of Glycine max (soybean). Candidate loci were detected that putatively contribute to adaptation to abiotic stresses.

          SNP Genotyping Data from the Barley Experimental Population from "Two Genomic Regions Contribute Disproportionately to Geographic Differentiation in Wild Barley"

            The 318 sampled wild barley accensions, known as the Wild Barley Diversity Collection (WBDC), were genotyped using the Illumina Golden Gate Genotyping Assay with two Barley Oligo Pool assay chips (BOPA1 and BOPA2). The genotype calls were based on machine-scored data using the program ALCHEMY and the SNPs were annotated using the program SNPMeta. The BOPA1 & 2 files contains the output of the ALCHEMY program.

            Data from: Exome genotyping, linkage disequilibrium and population structure in loblolly pine (Pinus taeda L.)

              Loblolly pine (*Pinus taeda* L.) is one of the most widely planted and commercially important forest tree species in the USA and worldwide, and is an object of intense genomic research. However, whole genome resequencing in loblolly pine is hampered by its large size and complexity and a lack of a good reference. As a valid and more feasible alternative, entire exome sequencing was hence employed to identify the gene-associated single nucleotide polymorphisms (SNPs) and to genotype the sampled trees.

              Data from: Population structure and genetic diversity within the endangered species Pityopsis ruthii (Asteraceae)

                *Pityopsis ruthii* (Ruth’s golden aster) is a federally endangered herbaceous perennial endemic to the Hiwassee and Ocoee Rivers in southeastern Tennessee, USA. Comprehensive genetic studies providing novel information to conservationists for preservation of the species are lacking. Genetic variation and gene flow were evaluated for 814 individuals from 33 discrete locations using polymorphic microsatellites: seven chloroplast and twelve nuclear. A total of 198 alleles were detected with the nuclear loci and 79 alleles with the chloroplast loci.