Discriminant analysis of principal components and pedigree assessment of genetic diversity and population structure in a tetraploid potato panel using SNPs

The reported narrow genetic base of cultivated potato (Solanum tuberosum) can be expanded by the introgression of many related species with large genetic diversity. The analysis of the genetic structure of a potato population is important to broaden the genetic base of breeding programs by the identification of different genetic pools. A panel composed by 231 diverse genotypes was characterized using single nucleotide polymorphism (SNP) markers of the Illumina Infinium Potato SNP Array V2 to identify population structure and assess genetic diversity using discriminant analysis of principal components (DAPC) and pedigree analysis. Results revealed the presence of five clusters within the populations differentiated principally by ploidy, taxonomy, origin and breeding program. The information obtained in this work could be readily used as a guide for parental introduction in new breeding programs that want to maximize variability by combination of contrasting variability sources such as those presented here.Fil: Deperi, Sofía Irene. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; ArgentinaFil: Tagliotti, Martin Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; ArgentinaFil: Bedogni, María Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Manrique Carpintero, Norma C.. Michigan State University; Estados UnidosFil: Coombs, Joseph. Michigan State University; Estados UnidosFil: Zhang, Ruofang. Inner Mongolia University; ChinaFil: Douches, David. Michigan State University; Estados UnidosFil: Huarte, Marcelo Atilio. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; Argentin

Use of easy measurable phenotypic traits as a complementary approach to evaluate the population structure and diversity in a high heterozygous panel of tetraploid clones and cultivars

Diversity in crops is fundamental for plant breeding efforts. An accurate assessment of genetic diversity, using molecular markers, such as single nucleotide polymorphism (SNP), must be able to reveal the structure of the population under study. A characterization of population structure using easy measurable phenotypic traits could be a preliminary and low-cost approach to elucidate the genetic structure of a population. A potato population of 183 genotypes was evaluated using 4859 high-quality SNPs and 19 phenotypic traits commonly recorded in potato breeding programs. A Bayesian approach, Minimum Spanning Tree (MST) and diversity estimator, as well as multivariate analysis based on phenotypic traits, were adopted to assess the population structure. Results: Analysis based on molecular markers showed groups linked to the phylogenetic relationship among the germplasm as well as the link with the breeding program that provided the material. Diversity estimators consistently structured the population according to a priori group estimation. The phenotypic traits only discriminated main groups with contrasting characteristics, as different subspecies, ploidy level or membership in a breeding program, but were not able to discriminate within groups. A joint molecular and phenotypic characterization analysis discriminated groups based on phenotypic classification, taxonomic category, provenance source of genotypes and genetic background. Conclusions: This paper shows the significant level of diversity existing in a parental population of potato as well as the putative phylogenetic relationships among the genotypes. The use of easily measurable phenotypic traits among highly contrasting genotypes could be a reasonable approach to estimate population structure in the initial phases of a potato breeding program.Fil: Tagliotti, Martin Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Deperi, Sofía Irene. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; ArgentinaFil: Bedogni, María Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Zhang, Ruofang. Inner Mongolia University; ChileFil: Manrique Carpintero, Norma C.. Michigan State University; Estados UnidosFil: Coombs, Joseph. Michigan State University; Estados UnidosFil: Douches, David. Michigan State University; Estados UnidosFil: Huarte, Marcelo Atilio. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; Argentin

Association mapping to detect Phytophthora infestans Mont. De Bary resistance in tetraploid potato

Phytophthora infestans (Mont.) de Baryis found in all areas of potato (Solanum tuberosum L.) production in Argentine. Association mapping uses the existing diversity in a a population to identify loci responsible of phenotypic variation of a character. The studied population was formed by 159 genotypes of the germplasm collection of the Instituto Nacional de Tecnología Agropecuaria (INTA) Estación Experimental Agropecuaria (EEA) Balcarce potato breeding program. These genotypes are part of a larger population that was previously analyzed using single-nucleotide polymorphism (SNP). Phenotypic assessment was carried out in two locations over 3 yr. Environmental conditions allowed the presence of the disease in all year × location combination. Phenotypic variability was found for relative area under disease progress curve (RAUDPC) and yield parameters as, Total weight and Seed weight. Association mapping was carried out on 159 genotypes. Eight significant associations were found using Bonferroni methodology, with values of −log(p) ranging between 4.61 and 5.42 located at chromosomes 3 (solcap_snp_c2_16679), 4 (solcap_snp_c1_6126 and solcap_snp_c2_38243, solcap_snp_c2_54077), 5 (solcap_snp_c2_42374), 6 (solcap_snp_c2_33228), 7 (solcap_snp_c1_7407), and 10 (solcap_snp_c2_63) and eleven significant associations using permutation tests with values of −log(p) between 4.5 and 6.42 located at chromosomes 1(solcap_snp_c1_5150), 2 (solcap_snp_c1_13923), 4 (solcap_snp_c1_4178, and solcap_snp_c2_50004), 5 (solcap_snp_c2_11829 and solcap_snp_c2_50532), 7 (solcap_snp_c2_35057 and solcap_snp_c1_10011), and 9 (solcap_snp_c2_1915). Some of the SNPs detected are adjacent to genes that encode enzymes that participate in metabolic pathways that are activated in response to interaction with pathogens. Those markers might be included in breeding programs related to improve late blight resistance in potato cultivars.Fil: Deperi, Sofía Irene. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Tagliotti, Martin Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Bedogni, María Cecilia. Universidad Nacional de Mar del Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Huarte, Marcelo Atilio. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; Argentin

Genome‐wide association analysis of agronomical and physiological traits linked to drought tolerance in a diverse potatoes ( Solanum tuberosum ) panel

Potatoes is often considered a drought-sensitive crop and its sustainable production is threatened due to frequent drought episodes. Drought tolerance is a complex trait of increasing importance in potatoes therefore its yield is threatened. The differential response of several physiological and agronomical traits was evaluated in a diverse potatoes panel under contrasting water regimes to identify quantitative trait loci (QTL) associated with drought tolerance using genome-wide association analysis with 4859 high-quality SNP markers. Phenotypic data were collected from multiple environments and years. QTL with diverse linkage disequilibrium blocks for proline concentration, water consumption and yield were detected on chromosomes 1, 4 and 10. These QTL detected were associated with known gene functions. The current study provides insights into the putative genes that controlled the responses to the drought tolerance in potatoes at physiological and agronomical levels. The QTL described in this work might be included in future marker-assisted selection programmes linked with drought tolerance in potatoes.Fil: Tagliotti, Martin Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible - Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible; ArgentinaFil: Deperi, Sofía Irene. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible - Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible; ArgentinaFil: Bedogni, María Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible - Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; ArgentinaFil: Huarte, Marcelo Atilio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible - Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible; Argentin

Homoploid hybridization in the origin and evolution of wild diploid potato species

The potatoes, Solanum L. section Petota Dumortier, are a group of species that possess a very broad range of biological diversity, and a wide geographical distribution in the Americas. These species constitute euploid series with somatic chromosome numbers ranging from 2n = 2x = 24 to 2n = 6x = 72. Although special attention has been given to the origin of polyploid potato species, principally the cultivated forms, that are major food crops, and hybridization has been accepted as an important evolutionary force in the section, the mechanisms involved in the origin and evolution of the diploid species have not been elucidated. Herein, we propose that homoploid hybridization is the main mechanism involved in the origin and evolution of the diploid potato species, and discuss the evidences that support our proposal.Fil: Masuelli, Ricardo Williams. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Mendoza-San Juan. Estación Experimental Agropecuaria La Consulta; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; ArgentinaFil: Camadro, Elsa Lucila. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; Argentina. Universidad Nacional de Mar del Plata; ArgentinaFil: Erazzú, Luis Ernesto. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucuman-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; ArgentinaFil: Bedogni, María Cecilia. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; Argentina. Universidad Nacional de Mar del Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Marfil, Carlos Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; Argentin