Aplicación y desarrollo de herramientas moleculares modernas para el estudio genético especies forestales nativas de la Amazonía peruana

Se presentó un resumen de las investigaciones que se han ido publicando, así como, las tecnologías y metodologías que se viene utilizando en cuanto al estudio genético de especies forestales nativas de la Amazonía peruana. Se expuso sobre la problemática que es principalmente la falta de secuenciamiento de genoma de las distintas especies forestales. Se detalló el esquema de un proyecto de secuenciamiento que consta de los siguientes pasos: Obtención de la muestra, purificación del ADN genómico, fragmentación del ADN genómico, secuenciamiento de los fragmentos en la biblioteca, ensamblaje de las secuencias obtenidas y finalmente la anotación de genoma

Genetic structure and diversity of a peruvian collection of a high-quality wood tree species, Ulcumano (Retrophyllum rospigliosii, Podocarpaceae

Ulcumano, which is native to South America, is an important conifer in Peru. Molecular studies are scarce, limiting modern breeding and appropriate conservation activities. Currently, molecular markers are widely employed to explore genetic structure and diversity parameters of plant species in a fast and precise manner. The objective of this study was to analyze the genetic diversity and population structure of ulcumano in Peru by using DNA-based molecular markers. Nine Randomly Amplified Polymorphic DNA (RAPD) markers were used, while 95 individuals of ulcumano were sampled from three departments of Peru. A total of 265 DNA fragments were manually scored, but 247 of them were kept after removing the non-polymorphic markers. Genetic distances were calculated using R software based on Provesti´s coefficient. A dendrogram was obtained using the UPGMA clustering algorithm, showing no clear clustering. The principal coordinate analysis agreed with two population structure analyses, demonstrating that ulcumano is contained within two clusters, (i) Junín + Pasco, and (ii) Cajamarca, while very few individuals are intermixed. Genetic diversity parameters were estimated considering the two groups (populations) identified by STRUCTURE software. Nei’s genetic diversity estimate varied between 0.22 and 0.28, while Shannon index ranged from 3.43 to 4.16. Population divergence (Fst) between the two clusters revealed low genetic differentiation (0.064). AMOVA analysis revealed that 87.31 and 12.69% of the total genetic variation were found within populations and between individuals, respectively. To the best of our knowledge, this is the first molecular study in ulcumano in Peru, and provides valuable information for the genetic improvement and sustainable management of this conifer in the country

Genetic Diversity and Population Structure of Capirona (Calycophyllum spruceanum Benth.) from the Peruvian Amazon Revealed by RAPD Markers

Capirona (Calycophyllum spruceanum Benth.) is a tree species of commercial importance widely distributed in South American forests that is traditionally used for its medicinal properties and wood quality. Studies on this tree species have been focused mainly on wood properties, propagation, and growth. However, genetic studies on capirona have been very limited to date. Currently, it is possible to explore genetic diversity and population structure in a fast and reliable manner by using molecular markers. We here used 10 random amplified polymorphic DNA (RAPD) markers to analyze the genetic diversity and population structure of 59 samples of capirona that were sampled from four provinces located in the eastern region of the Peruvian amazon. A total of 186 bands were manually scored, generating a 59 × 186 presence/absence matrix. A dendrogram was generated using the UPGMA clustering algorithm, and, similar to the principal coordinate analysis (PCoA), it showed four groups that correspond to the geographic origin of the capirona samples (LBS, Irazola, Masisea, Iñapari). Similarly, a discriminant analysis of principal components (DAPC) and STRUCTURE analysis confirmed that capirona is grouped into four clusters. However, we also noticed that a few samples were intermingled. Genetic diversity estimation was conducted considering the four groups (populations) identified by STRUCTURE software. AMOVA revealed the greatest variation within populations (71.56%) and indicated that variability among populations is 28.44%. Population divergence (Fst) between clusters 1 and 4 revealed the highest genetic difference (0.269), and the lowest Fst was observed between clusters 3 and 4 (0.123). RAPD markers were successful and effective. However, more studies are needed, employing other molecular tools. To the best of our knowledge, this is the first investigation employing molecular markers in capirona in Peru considering its natural distribution, and as such it is hoped that this helps to pave the way towards its genetic improvement and the urgent sustainable management of forests in Peru

Unlocking the Complete Chloroplast Genome of a Native Tree Species from the Amazon Basin, Capirona (Calycophyllum spruceanum Benth., Rubiaceae), and Its Comparative Analysis with Other Ixoroideae Species

Capirona (Calycophyllum spruceanum Benth.) belongs to subfamily Ixoroideae, one of de major lineages in the Rubiaceae family, and is an important timber tree, with origin in the Amazon Basin and has widespread distribution in Bolivia, Peru, Colombia, and Brazil. In this study, we obtained the first complete chloroplast (cp) genome of capirona from department of Madre de Dios located in the Peruvian Amazon. High-quality genomic DNA was used to construct librar-ies. Pair-end clean reads were obtained by PE 150 library and the Illumina HiSeq 2500 platform. The complete cp genome of C. spruceanum has a 154,480 bp in length with typical quadripartite structure, containing a large single copy (LSC) region (84,813 bp) and a small single-copy (SSC) region (18,101 bp), separated by two inverted repeat (IR) regions (25,783 bp). The annotation of C. spruceanum cp genome predicted 87 protein-coding genes (CDS), 8 ribosomal RNA (rRNA) genes, 37 transfer RNA (tRNA) genes and 01 pseudogene. A total of 41 simple sequence repeats (SSR) of this cp genome were divided into mononucleotides (29), dinucleotides (5), trinucleotides (3), and tetranucleotide (4). Most of these repeats were distributed in the noncoding regions. Whole chloroplast genome comparison with the other six Ixoroideae species revealed that the small single copy and large single copy regions showed more divergence than invert regions. Finally, phylogenetic analysis resolved that C. spruceanum is a sister species to Emmenopterys henryi, and confirms its position within the subfamily Ixoroideae. This study reports for the first time the genome organization, gene content, and structural features of the chloroplast genome of C. spruceanum, providing valuable information for genetic and evolutionary studies in the genus Calycophyllum and beyond

Characterization of the complete chloroplast genome of a Peruvian landrace of Capsicum chinense Jacq. (Solanaceae), arnaucho chili pepper

In this study, we sequenced the first complete chloroplast (cp) genome of a Peruvian chili pepper landrace, “arnacucho” (Capsicum chinense). This cp genome has a 156,931 bp in length with typical quadripartite structure, containing a large single copy (LSC) region (87,325 bp) and a 17,912 bp small single-copy (SSC) region, separated by two inverted repeat (IR) regions (25,847 bp); and the percentage of GC content was 37.71%. Arnaucho chili pepper chloroplast genome possesses 133 genes that consists of 86 protein-coding genes, 37 tRNA, eight rRNA, and two pseudogenes. Phylogenetic analysis revealed that this Peruvian chili pepper landrace is closely related to the undomesticated species C. galapagoense; all belong to the Capsiceae tribe

Characterization of the complete chloroplast genome of a Peruvian landrace of Capsicum chinense Jacq. (Solanaceae), arnaucho chili pepper

In this study, we sequenced the first complete chloroplast (cp) genome of a Peruvian chili pepper landrace, “arnacucho” (Capsicum chinense). This cp genome has a 156,931 bp in length with typical quadripartite structure, containing a large single copy (LSC) region (87,325 bp) and a 17,912 bp small single-copy (SSC) region, separated by two inverted repeat (IR) regions (25,847 bp); and the percentage of GC content was 37.71%. Arnaucho chili pepper chloroplast genome possesses 133 genes that consists of 86 protein-coding genes, 37 tRNA, eight rRNA, and two pseudogenes. Phylogenetic analysis revealed that this Peruvian chili pepper landrace is closely related to the undomesticated species C. galapagoense; all belong to the Capsiceae tribe

Revealing the Complete Chloroplast Genome of an Andean Horticultural Crop, Sweet Cucumber (Solanum muricatum), and Its Comparison with Other Solanaceae Species

Sweet cucumber (Solanum muricatum) sect. Basarthrum is a neglected horticultural crop native of the Andean region. It is naturally distributed very close to other two Solanum crops of high importance, potatoes and tomatoes. To date, molecular tools for this crop are still undetermined. In this study, the complete sweet cucumber chloroplast (cp) genome was obtained and compared with seven Solanaceae species. The cp genome of S. muricatum had a 155,681 bp in length with included a large single copy (LSC) region of 86,182 bp and a small single-copy (SSC) region of 18,360 bp, separated by a pair of inverted repeats (IR) regions of 25,568 bp. The cp genome possessed 88 protein-coding genes (CDS), 37 transfer RNA (tRNA) genes, eight ribosomal RNA (rRNA) genes, and one pseudogene. Furthermore, 48 perfect microsatellites were identified, divided in mononucleotide repeats (32), followed by tetranucleotide (6) and dinucleotides (5). Microsatellites with trinucleotides repeats (3), pentanucleotide (1) and hexanucleotide (1) repeats motifs in these genomes were also identified, but in lower quantity. These repeats were mainly located in the noncoding regions. Whole cp genome comparative analysis revealed that the SSC and LSC regions showed more divergence than IR regions. Our phylogenetic analysis showed that S. muricatum is a sister species to members of sections Petota + Lycopersicum + Etuberosum. We expect to provide useful molecular data to shed light on the genetic diversity within sweet cucumber landrace, and also to determine the evolutionary processes in S. muricatum

Caracterización genética de Cedrelinga Cateniformis ‟tornillo” provenientes de cinco regiones del Perú utilizando marcadores moleculares RAPDS (Random Amplified Polymorphic Dna)

Cedrelinga cateniformis Ducke, “tornillo”, es una especie árborea con centro de distribución natural en la Amazonía Peruana. Presenta buen crecimiento y una alta productividad en plantaciones, por lo que es considerada como una especie promisoria para los trabajos de reforestación, además produce una madera que tiene alta demanda en el mercado nacional e internacional debido a sus buenas características de manejabilidad y resistencia. El limitado conocimiento de las características genotípicas, de la estructura poblacional y diversidad genética de “tornillo” son el principal problema para el establecimiento de plantaciones masivas con características genéticas de interés y para el diseño de estrategias de uso sostenible, conservación y reforestación de la especie. El objetivo de la presente investigación fue caracterizar genéticamente a los individuos de ״tornillo״ provenientes de cinco regiones del Perú basada en la amplificación de marcadores moleculares RAPDs (Random Amplified Polymorphic DNA) para lo cual se diseñó un experimento con 44 marcadores genéticos, cuyos protocolos fueron previamente estandarizados para extracción de ADN, PCR, y electroforesis. Se seleccionaron cinco iniciadores que generaron productos de amplificación reproducibles, siendo un total de 95 loci, de los cuales 86 fueron polimórficos con un índice de polimorfismo de 90.5 % y coeficiente de similardad (Simple Matching) de 0.78. Con el paquete estadístico NTSYSpc v2.1p y con el análisis de agrupamiento UPGMA (Unweighted Pair Group Method using Arithmetic Averages) se generó un dendograma en el que se observaron tres agrupamientos principales con un 56 % de similitud. Según estos resultados, existe variabilidad dentro de las poblaciones de C. Cateniformis, además los marcadores RAPDs podrían usarse como herramientas de bajo costo para facilitar la caracterización genéticaTesi