El departamento de Cundinamarca participa con aproximadamente 27% de la producción de leche en Colombia, con desventajas competitivas en cuanto a la calidad del producto (proteína, grasa y sólidos totales); lo cual influye en su participación en el mercado, ya que las empresas lácteas elaboran sus esquemas de pago basándose en estas características de producción. Debido a esta situación, Corpoica ha implementado programas de mejoramiento basados en la selección asistida por marcadores moleculares. Bajo este esquema, se han encontrado diversos polimorfismos genéticos asociados con características de producción de leche bovina; particularmente, en el exón 4 del gen de β-lactoglobulina, donde se ha descrito una variante asociada con producción de caseínas y grasa. El objetivo del presente estudio fue estimar las frecuencias alélicas y genotípicas de β-lactoglobulina en seis poblaciones Holstein de la sabana de Bogotá, mediante la técnica de PCR-RFLP. Para la genotipificación se amplificó un fragmento de 247 pb, digerido con la enzima de restricción Hae III. Las frecuencias de los alelos A y B encontradas en la población son similares (0,51 y 0,49 respectivamente). Estos valores coinciden con los reportados en ganado Holstein europeo. Sin embargo, la distribución de frecuencias genotípicas varía de las frecuencias reportadas mundialmente para ganado lechero. El principal genotipo encontrado fue el AA (0,35), seguido por el BB (0,31). La distribución de los genotipos y de los alelos en la población fue muy similar, lo cual puede estar relacionado con la falta de implementación de programas de mejoramiento en la sabana de Bogotá.

Background The genus Elaeis has two species of economic importance for the oil palm agroindustry: Elaeis oleifera (O), native to the Americas, and Elaeis guineensis (G), native to Africa. The work presented herein provides, to our knowledge, the first association mapping study in an interspecific OxG hybrid population of oil palm which presents tolerance to pests and diseases, high oil quality, and acceptable fruit bunch production. Results Using genotyping-by-sequencing (GBS), we identified a total of 3,776 single nucleotide polymorphisms (SNPs) that were used to perform a genome-wide association analysis (GWAS) in 378 OxG hybrids for 10 agronomic traits. Twelve genomic regions were located near candidate genes implicated in multiple functional categories, such as tissue growth, cellular trafficking, and physiological processes. Conclusions We provide new insights on candidate genes that mapped on genomic regions involved in plant architecture and yield; however, these potential candidate genes need to be confirmed for future targeted functional analysis. The associated markers may be valuable resources for the development of marker-assisted selection in oil palm breeding. Keywords: Association mapping, Elaeis guineensis, Elaeis oleifera, genotyping-by-sequencing, plant architecture, yield.

Background The genus Elaeis has two species of economic importance for the oil palm agroindustry: Elaeis oleifera (O), native to the Americas, and Elaeis guineensis (G), native to Africa. The breeding program in Colombia relies on interspecific OxG crossing populations with tolerance to pests and diseases, high oil quality, and acceptable fruit bunch production. The identification of loci associated to morphological and yield-related traits and the dissection of their genetic architecture will provide essential insights for oil palm breeding strategies. Results The genotypes of 471 oil palms, including 62 E. oleifera (O), 31 E. guineensis (G) and 378 OxG samples were analyzed in this study. A total of 3,776 single nucleotide polymorphisms (SNP) were detected across the 16 oil palm chromosomes using the genotyping-by-sequencing (GBS) technique. The genetic variation and population structure analyses grouped the samples into two clades according to the parental relatedness. A genome wide association analysis (GWAS) was conducting using the OxG hybrid population, resulting in 12 SNPs significantly associated with ten different morphological and yield-related traits. Conclusions The work presented herein provides to our knowledge the first association mapping study in an interspecific OxG hybrid population of oil palm. We provide new insights on candidate genes involved in tissue development and plant architecture associated to traits such as: rachis length, trunk diameter, bunch number, and bunch weight. The genes identified in our analysis are putative candidates for future targeted functional analysis. They are valuable resources for the development of marker-assisted selection in oil palm breeding. Keywords: Association mapping, Elaeis guineensis, Elaeis oleifera, genotyping-by-sequencing, plant architecture, yield.

Background The genus Elaeis has two species of economic importance for the oil palm agroindustry: Elaeis oleifera (O), native to the Americas, and Elaeis guineensis (G), native to Africa. This work provides to our knowledge, the first association mapping study in an interspecific OxG oil palm population, which shows tolerance to pests and diseases, high oil quality, and acceptable fruit bunch production. Results Using genotyping-by-sequencing (GBS), we identified a total of 3,776 single nucleotide polymorphisms (SNPs) that were used to perform a genome-wide association analysis (GWAS) in 378 OxG hybrid population for 10 agronomic traits. Twelve genomic regions (SNPs) were located near candidate genes implicated in multiple functional categories, such as tissue growth, cellular trafficking, and physiological processes. Conclusions We provide new insights on genomic regions that mapped on candidate genes involved in plant architecture and yield. These potential candidate genes need to be confirmed for future targeted functional analyses. Associated markers to the traits of interest may be valuable resources for the development of marker-assisted selection in oil palm breeding. Keywords: Association mapping, Elaeis guineensis , Elaeis oleifera , genotyping-by-sequencing, plant architecture, yield.

Background The genus Elaeis has two species of economic importance for the oil palm agroindustry: Elaeis oleifera (O), native to the Americas, and Elaeis guineensis (G), native to Africa. This work provides to our knowledge, the first association mapping study in an interspecific OxG oil palm population, which shows tolerance to pests and diseases, high oil quality, and acceptable fruit bunch production. Results Using genotyping-by-sequencing (GBS), we identified a total of 3,776 single nucleotide polymorphisms (SNPs) that were used to perform a genome-wide association analysis (GWAS) in 378 OxG hybrid population for 10 agronomic traits. Twelve genomic regions (SNPs) were located near candidate genes implicated in multiple functional categories, such as tissue growth, cellular trafficking, and physiological processes. Conclusions We provide new insights on genomic regions that mapped on candidate genes involved in plant architecture and yield. These potential candidate genes need to be confirmed for future targeted functional analyses. Associated markers to the traits of interest may be valuable resources for the development of marker-assisted selection in oil palm breeding. Keywords: Association mapping, Elaeis guineensis , Elaeis oleifera , genotyping-by-sequencing, plant architecture, yield.