Examinando por Materia "Conservation genetics"

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Genetic diversity and population structure of Myrciaria dubia from the Peruvian Amazon: implications for germplasm conservation and crop improvement
(Springer Nature, 2026-03-27) Mejía de Loayza, Eduardo; Estivals, Guillain; Castro Ruiz, Diana; Chota Macuyama, Werner; Angulo Chávez, Carlos; Corazon Guivin, Mike; Rodríguez del Castillo, Ángel Martín; Alvarado Reategui, Jhon; Angulo Villacorta, Carlos; Mejía, Kember; Del Castillo Torres, Dennis; García Dávila, Carmen
Myrciaria dubia (camu-camu) is a shrubby fruit tree native to the continental Amazon whose fruits have been intensively harvested from wild stands, potentially reducing effective population sizes. We quantified genetic diversity and population structure across seven wild Peruvian Amazon populations and delineated river-basin genetic units to guide provenance-aware germplasm conservation and breeding. We genotyped 254 individuals from the Napo, Ucayali, Nanay, Tahuayo, Putumayo, Tigre, and Curaray basins using six polymorphic microsatellite loci. Overall, 48 alleles were detected. Observed heterozygosity (0.149–0.483) was generally lower than expected heterozygosity (0.220–0.531), and population-level inbreeding coefficients (FIS=−0.038– 0.560) indicated significant heterozygote deficits in Napo, Curaray, and Tahuayo. The Putumayo population harbored nine private alleles, representing a unique genetic reservoir. Pairwise differentiation was substantial (FST=0.093–0.660; Nei’s distance=0.068–1.734), with the strongest divergence between Tigre and Ucayali. Neighbor-joining, Bayesian assignment, and Discriminant Analysis of Principal Components (DAPC) initially supported three major genetic units and highlighted Putumayo as genetically isolated; additionally, hierarchical STRU CTURE analyses resolved eight clusters, and DAPC distinguished seven population-specific groups. Analysis of molecular variance attributed 56.5% of the variation within individuals and 34.7% among populations. Mantel tests supported isolation by distance based on straight-line geographic distances (r=0.53– 0.56; p≤0.017), whereas river-network distances were not significant. Overall, the data indicate a geographically structured genetic architecture shaped by dispersal limitation and basin-scale differentiation, supporting three provenance units for germplasm banking and breeding: (i) Napo–Ucayali–Nanay– Tahuayo, (ii) Tigre–Curaray, and (iii) Putumayo.
Genomic characterization of Peruvian Creole goats: insights into population structure and runs of homozygosity
(Animals, 2025-09-02) Corredor Arizapana, Flor Anita; Godoy Padilla, David José; Sessarego Dávila, Emmanuel Alexander; Temoche Socola, Victor Alexander; Paredes Chocce, Miguel Enrique; Escobar Robledo, Héctor Manuel; Ramírez Antaurco, Máximo Fabricio; Burgos Paz, William; Ruiz Chamorro, José Antonio; Cruz Luis, Juancarlos Alejandro; Mulim, Enrique A.; Rojas de Oliveira, Hinayah
Peruvian Creole goats (PCGs) represent a unique genetic resource shaped by adaptation to diverse environments and traditional breeding practices. In this study, we performed a genomic analysis of six regional populations (Ancash, Ica, Lambayeque, Lima, Piura, and Tumbes) using high-density SNP genotype data. Principal component analysis revealed a moderate genetic structure, with the Ica population showing clear separation and northern populations exhibiting overlap. Runs of homozygosity were predominantly short, and specific regions on chromosome 6 were shared across populations. Inbreeding coefficients were generally low, with Ancash showing the highest values. Linkage disequilibrium decayed rapidly over genetic distance, especially in Piura, indicating higher genetic diversity. Estimates of effective population size revealed decreasing trends across populations, with Piura maintaining the largest recent population size. These findings offer valuable insights into the population structure of Peruvian Creole goats, providing guidance for conservation and sustainable breeding efforts.