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Genetic structure of populations of Anastrepha ludens (Diptera: Tephritidae) in Mexico

Mayra Carolina Molina Nery Lorena Ruiz Montoya Cristina Silvia Zepeda Cisneros Pablo Liedo (2014)

Resumen en español: "La amplia distribución de Anastrepha ludens (Loew) (Diptera: Tephritidae) en México y el uso de diferentes plantas hospederas taxonómicamente no relacionadas sugiere que esta es una especie con alto potencial evolutivo y representa una plaga de alto riesgo. Se investigó la diversidad y estructura genética de poblaciones de Anastrepha ludens en siete estados de la República Mexicana (Chiapas, Yucatán, Morelos, Veracruz, San Luis Potosí, Tamaulipas y Durango). Las moscas se colectaron como larvas dentro de frutos de cítricos en cada estado, y se enviaron como pupas al Laboratorio de Sexado Genético de la planta “Moscafrut” en Metapa, Chiapas, en donde emergieron los adultos y se analizaron genéticamente. La diversidad genética de las poblaciones se estimó con base en la heterocigosidad observada y esperada, se obtuvo el número promedio de alelos y el polimorfismo, con base en las frecuencias alélicas y genotípicas de seis loci enzimáticos revelados en acetatos de celulosa. La heterocigosidad esperada (He) fue de 0.199 a 0.330, y el porcentaje de loci polimórficos (P) fue entre 50 y 67%. Se encontró un alto coeficiente de endogamia (Fis= 0.393, Fit = 0.456) y una diferenciación genética moderada entre poblaciones (Fis = 0.393, Fit = 0.456). La correlación entre la altitud y He fue negativa. Concluimos que las poblaciones de A. ludens son genéticamente diversas y con nivel de diferenciación moderado. La estructura genética no pudo ser atribuida a la distancia geográfica entre poblaciones. Probablemente, la diferenciación pueda ser resultado de la selección asociada al proceso de colonización. La deriva genetica y las prácticas de manejo posiblemente han contribuido a esta diferenciación en menor grado. "

Resumen en inglés: "The wide geographic range of Anastrepha ludens (Loew) (Diptera: Tephritidae) in Mexico and its ability to use various taxonomically unrelated host plant species suggests that this species has considerable evolutionary potential and represents a high risk pest. The genetic diversity and structure of A. ludens populations from 7 Mexican states (Chiapas, Yucatán, Morelos, Veracruz, San Luis Potosí, Tamaulipas and Durango) were investigated. Flies were collected as larvae from infested citrus fruits in each state, and sent as pupae to the Genetic Sexing Laboratory at the “Moscafrut ” facility in Metapa, Chiapas, where adults emerged and were used in isoenzymatic analysis. Genetic diversity was estimated based on expected and observed heterozygosity, mean number of alleles and polymorphism obtained from allelic and genotypic frequencies of 6 enzyme loci revealed in cellulose acetate. Expected heterozygosity (He) ranged from 0.199 to 0.330, and percentage of polymorphic loci (P) was between 50 and 67%. We found a high level of inbreeding (Fis = 0.393, Fit = 0.456) and moderate genetic differentiation among populations (Fst = 0.105). A negative correlation was found between elevation and He. We conclude that A. ludens populations are genetically diverse with moderate levels of differentiation. Genetic structure could not be attributed to the geographic distance among populations. Differentiation could be the result of natural selection associated with the colonization process. Genetic drift and pest management practices may have contributed to this differentiation to a lesser extent. "

Article

Moscas de la fruta;Variación genética;Genética de población;Citrus aurantium;Naranjas;Citrus paradisi Fruit flies;Genetic variation;Population genetics;Citrus aurantium;Oranges;Grapefruit BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA CIENCIAS DE LA VIDA

Diferenciación genética y demográfica de poblaciones de Anastrepha ludens (Diptera: Tephritidae) en México

Mayra Carolina Molina Nery (2011)

Resumen en español: "En este trabajo se estimó la variación aloenzimática y demográfica, y el flujo genético entre poblaciones de Anastrepha ludens en siete estados de la república (Chiapas, Durango, Morelos, San Luis Potosí, Tamaulipas, Veracruz y Yucatán) para reconocer el grado de conexión o aislamiento entre poblaciones separadas geográficamente. En cada estado se colectaron frutos de Citrus spp. infestados con larvas de A. ludens, una vez que se obtuvieron las pupas se enviaron al laboratorio de Sexado Genético- Programa MOSCAFRUT en Metapa de Domínguez, Chiapas. Se realizó el análisis genético con ejemplares adultos de cada población. Se estimó la variación aloenzimática en seis loci y el grado de diferenciación genética entre poblaciones y flujo genético (Nm). Mediante un análisis de asignación de genotipos multilocus se estimó el número probable de individuos inmigrantes. La heterocigosidad esperada (He) varió de 0.199 a 0.330, el polimorfismo (P) entre 50 y 66%. La diferenciación genética entre poblaciones fue de FST=0.09. El flujo genético (Nm) entre pares de poblaciones varió entre 0.8 y 37 individuos por generación y fue negativamente asociado con la distancia geográfica lineal que separa las poblaciones. El análisis de asignación multilocus reveló un patrón de flujo asimétrico entre poblaciones. Para el análisis demográfico se mantuvieron grupos de 50 parejas de adultos en jaulas a 24°C, durante dos generaciones. Se tomaron muestras de los huevecillos ovipositados a partir de estos se registró la supervivencia en cada uno de los diferentes estados fisiológicos (H-L, L1 a L3, L3-P, P-A). La supervivencia de la población de Morelos fue mayor y significativamente diferente al resto de las poblaciones en la generación parental. En la generación F1 las poblaciones de Chiapas y Durango alcanzaron los valores más altos de supervivencia y fueron significativamente diferentes al resto de las poblaciones. No se encontró relación entre la heterocigosidad (He) y la supervivencia. Se discute la implicación que estos resultados pueden tener sobre las acciones de manejo de la Campaña Nacional contra Moscas de la Fruta. "

Master thesis

Moscas de la fruta;Variación genética;Población de insectos;Morfología (Biología) Fruit flies;Genetic variation;Insect populations;Morphology BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA CIENCIAS DE LA VIDA

Respuesta olfativa de Anastrepha striata Schiner (Diptera: tephritidae) a volátiles de frutos de Psidium guajava y Citrus sinensis

Edvin Díaz Santiz (2014)

Resumen en español: "Se evaluó la respuesta olfativa de hembras vírgenes y apareadas de Anastrepha striata Schiner (Diptera: Tephritidae) a volátiles de frutos hospederos. La respuesta de las moscas a volátiles de frutos hospederos fue evaluada usando trampas Multilure cebadas con frutos no infestados de guayaba (Psidium guajava L.) y naranja dulce (Citrus sinensis L.), en pruebas de no elección en jaulas de campo, usando como control una trampa Multilure sin fruto. Los resultados indicaron que las moscas fueron igualmente atraídas a los volátiles de frutos de guayaba o naranja cuando fueron comparadas contra el control. Los volátiles emitidos por los frutos hospederos fueron capturados por aireación dinámica y analizada por cromatografía de gases acoplada a electroantenografia (CG-EAD) y cromatografía de gases-espectrometría de masas (CG-EM). Los compuestos antenalmente activos en los extractos de guayaba fueron identificados como butirato de etilo, (Z)-3-hexenol, hexanol, hexanoato de etilo, acetato de hexilo y octanoato de etilo, mientras que el linalol fue identificado como el único compuesto antenalmente activo en los extractos de naranja. La actividad biológica de los compuestos sintéticos identificados fue evaluada contra los extractos de frutos con hembras apareadas en pruebas en jaulas de campo. Los resultados mostraron que las hembras apareadas de A. striata responden de manera similar tanto al extracto de guayaba o la mezcla de seis componentes de guayaba, o al extracto de naranja y al linalol, lo que sugiere que los compuestos identificados son los responsables de la atracción. "

Master thesis

Anastrepha striata;Moscas de la fruta;Olfatometría;Compuestos volátiles;Huéspedes;Guayabas;Naranjas Guava fruitfly;Fruit flies;Olfactometry;Volatile compounds;Hosts;Guava;Oranges BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA CIENCIAS DE LA VIDA

First Report of Hop stunt viroid Infecting Citrus Trees in Morocco

Mohamed Afechtal fouad mokrini Abdelfattah DABABAT (2016)

Citrus fruits are an important contributor to the moroccan economy; the industry employs thousands of people and it also serves as a significant source of hard currency. During july 2014, a field survey for the presence of hop stunt viroid (hsvd) on citrus was conducted in the gharb region (northwestern morocco). Hsvd is a member of the pospiviroidae family and the hostuviroid genus. Its best known host is hop, but the viroid has a wide host range, including several woody and herbaceous crops. Forty samples without symptoms of viroid infection were randomly collected from four citrus orchards of different varieties: common and sidi aissa clementines (citrus clementina hort. ex tanaka), and valencia late and washington navel sweet oranges (c. sinensis (l.) Osbeck). Total rna extraction was performed on the samples using rneasy plant mini kit (qiagen, germany) and was then used for reverse transcription (rt)-pcr assays with primers specific to hsvd (kofalvi et al. 1997). The rt-pcr results showed that three samples tested positive to hsvd, yielding the expected size of 302 bp in agarose gel. Two positive samples were detected from two common clementine trees and the third was from a valencia late orange tree. Rt-pcr products from the positive samples from clementine were cloned to the puc18 plasmid vector (agilent technologies, usa), then one clone from each isolate was sequenced and deposited in genbank under accession numbers ku640953 and ku640954. Blast analysis of these sequences indicated 95 to 96% nucleotide identity with hsv-cit isolate from etrog citron (accession no. X06719). The positive results obtained by rt-pcr were confirmed by biological indexing for citrus cachexia using graft inoculation on parson’s special mandarin on rough lemon rootstock. After 16 months of incubation under greenhouse conditions (28 to 32°c), indicator plants graft-inoculated with bark tissue from hsvd-positive trees presented, at the bud-union, stem pitting and gumming affecting the parson’s special mandarin scion but not the rough lemon rootstock (roistacher et al. 1973). To our knowledge, this is the first report of hsvd in citrus trees in morocco, though this viroid was previously reported on apricot by amari et al. (2000). Cachexia is an economically important disease of citrus, and is included in the national health certification program for citrus. Researchers are currently studying the biological properties of these newly identified hsvd isolates, in addition to the field surveys for other viroids being undertaken in morocco’s main citrus growing areas.

Article

Citrus Fruit Sidi Aissa Clementines Hop Stunt Viroid CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Extreme genetic divergence in the endemic fish Chirostoma humboldtianum: implications for its conservation

Divergencia genética extrema en el pez endémico Chirostoma humboldtianum: implicaciones para su conservación

ROSA MARIA GARCIA MARTINEZ HECTOR OMAR MEJIA GUERRERO FRANCISCO JAVIER GARCIA DE LEON IRENE DE LOS ANGELES BARRIGA SOSA (2015)

"Chirostoma humboltianum is an endemic species widely distributed in isolated basins of Central México. However, habitat alteration had reduced the range of distribution and led to the local extinction of the species in some basins. During the Miocene these basins were connected, allowing dispersal and colonization of new hydrological systems. Later on, tectonic, volcanic and climatic events of the Plio-Pleistocene promoted continuous periods of isolation and reconnection allowing the species evolve through continuous cycles of expansion and contraction of its distribution. Therefore it is expected that these events have left signals in the geographical distribution and genetic diversity and divergence of existing populations. Although the analysis of genetic diversity and genetic structure in the population becomes an important factor for the conservation of a species, few studies have been made in this taxon. In this study we used a 341pb segment of the domain I of the hypervariable region of the mitochondrial control region to analyze the genetic diversity and their distribution in 20 individuals of each one of six lakes located in central México. The values of haplotypic (0 - 0.938) and nucleotide (0 - 0.0352) diversity suggested continuous periods of expansion and population contraction related with the formation of the lakes during the Pleistocene which is supported by the BSP and mismatch analysis, and recent anthropogenic factors. In addition, the large number of exclusive haplotypes (66%) and the highly significant genetic differentiation among populations suggests that each one of the population must be conserved because each one is an important component in the evolutionary legacy of the species. "

"Chirostoma humboltianum es una especie endémica ampliamente distribuida en cuencas aisladas del Centro de México. Sin embargo, la alteración del hábitat ha reducido drásticamente el área de distribución y llevado a la extinción local de la especie en algunas cuencas. Durante el Mioceno estas cuencas estuvieron conectadas, permitiendo la colonización y dispersión en nuevos sistemas hidrológicos. Posteriormente, los eventos tectónicos, volcánicos y climáticos del Plio-Pleistoceno promovieron continuos periodos de aislamiento y reconexión, permitiendo que la especie evolucionara a través de ciclos de expansión y contracción de su distribución. Por lo tanto, se espera que estos eventos hayan dejado huella en la distribución geográfica y diversidad genética de las poblaciones existentes. Si bien, el análisis de la diversidad genética en una población llega a ser un factor importante para la conservación de una especie, pocos estudios han sido realizados en este taxón. En este trabajo usamos un segmento de 341pb del dominio I hipervariable de la región control mitocondrial, para analizar la diversidad genética y su distribución para 20 individuos de cada uno de los seis lagos localizados en la región central de México. Los valores de diversidad haplotípica (0-0.938) y nucleotídica (0-0.0352) sugieren continuos periodos de expansión y contracción poblacional relacionado con la formación de los lagos en el Pleistoceno lo cual es soportado por los análisis BSP y mismatch; y de factores antropogénicos recientes. En adición, la gran cantidad de haplotipos exclusivos (66%) y la alta diferenciación genética significativa entre las poblaciones, sugiere que cada una de las poblaciones debe de ser conservada porque cada una es un componente importante en el legado evolutivo de la especie."

Article

Chirostoma humboldtinaum, control region, genetic diversity, population genetics diversidad genética, genética poblacional, región control BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA ANIMAL (ZOOLOGÍA) GENÉTICA ANIMAL GENÉTICA ANIMAL

Evaluation of agro-morphological diversity of groundnut (Arachis hypogaea L.) in Niger

Mainassara Zaman-Allah (2015)

This work evaluated a collection of hundred groundnut (Arachis hypogaea L.) varieties from different origin using twenty four (24) agro-morphological traits that can help to enhance selection efficiency in crop improvement. The experiment was carried out at the experimental station of INRAN-Tarna, in the region of Maradi (Niger) during the rainy season of 2010. Analysis of variance showed a large variability among varieties for the agro-morphological traits. Principal Component Analysis (PCA), Agglomerative Hierarchical Clustering (AHC) and Fisher Discriminant Analysis (FDA) revealed that this variability is structured into four distinct groups. Groups I and II consisted of early varieties that have a high emergence rate and high pods and seed weight. These groups included mainly local varieties and those introduced in Niger through seed dissemination. Groups III and IV are composed of late varieties with large pods while group III had mostly varieties with long leaflets. Understanding the genetic control of the most discriminating among the studied traits would bring significant contribution to the genetic improvement of this important crop.

Article

Arachis hypogaea Groundnuts Genetic variation CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Evaluation of agro-morphological diversity of groundnut (Arachis hypogaea L.) in Niger

Mainassara Zaman_Allah (2015)

This work evaluated a collection of hundred groundnut (Arachis hypogaea L.) varieties from different origin using twenty four (24) agro-morphological traits that can help to enhance selection efficiency in crop improvement. The experiment was carried out at the experimental station of INRAN-Tarna, in the region of Maradi (Niger) during the rainy season of 2010. Analysis of variance showed a large variability among varieties for the agro-morphological traits. Principal Component Analysis (PCA), Agglomerative Hierarchical Clustering (AHC) and Fisher Discriminant Analysis (FDA) revealed that this variability is structured into four distinct groups. Groups I and II consisted of early varieties that have a high emergence rate and high pods and seed weight. These groups included mainly local varieties and those introduced in Niger through seed dissemination. Groups III and IV are composed of late varieties with large pods while group III had mostly varieties with long leaflets. Understanding the genetic control of the most discriminating among the studied traits would bring significant contribution to the genetic improvement of this important crop.

Article

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA Arachis hypogaea Groundnuts Genetic variation

Genetic variation and population structure of maize inbred lines adapted to the mid-altitude sub-humid maize agro-ecology of Ethiopia using single nucleotide polymorphic (SNP) markers

Berhanu Tadesse Ertiro Kassa Semagn Biswanath Das Michael Olsen Maryke Labuschagne Mosisa Worku Regasa Dagne Wegary Gissa Veronica Ogugo Tolera Keno Abebe Menkir (2017)

Molecular characterization is important for efficient utilization of germplasm and development of improved varieties. In the present study, we investigated the genetic purity, relatedness and population structure of 265 maize inbred lines from the Ethiopian Institute of Agricultural Research (EIAR), the International Maize and Wheat Improvement Centre (CIMMYT) and the International Institute of Tropical Agriculture (IITA) using 220,878 single nucleotide polymorphic (SNP) markers obtained using genotyping by sequencing (GBS). Only 22% of the inbred lines were considered pure with <5% heterogeneity, while the remaining 78% of the inbred lines had a heterogeneity ranging from 5.1 to 31.5%. Pairwise genetic distances among the 265 inbred lines varied from 0.011 to 0.345, with 89% of the pairs falling between 0.301 and 0.345. Only <1% of the pairs had a genetic distance lower than 0.200, which included 14 pairs of sister lines that were nearly identical. Relative kinship analysis showed that the kinship coefficients for 59% of the pairs of lines was close to zero, which agrees with the genetic distance estimates. Principal coordinate analysis, discriminant analysis of principal components (DAPC) and the model-based population structure analysis consistently suggested the presence of three groups, which generally agreed with pedigree information (genetic background). Although not distinct enough, the SNP markers showed some level of separation between the two CIMMYT heterotic groups A and B established based on pedigree and combining ability information. The high level of heterogeneity detected in most of the inbred lines suggested the requirement for purification or further inbreeding except those deliberately maintained at early inbreeding level. The genetic distance and relative kinship analysis clearly indicated the uniqueness of most of the inbred lines in the maize germplasm available for breeders in the mid-altitude maize breeding program of Ethiopia. Results from the present study facilitate the maize breeding work in Ethiopia and germplasm exchange among breeding programs in Africa. We suggest the incorporation of high density molecular marker information in future heterotic group assignments.

Article

Maize Genetic variation Inbred lines CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

DIVERSIDAD GENETICA EN CERDOS CRIOLLOS MEXICANOS CON GENES CANDIDATOS ASOCIADOS A CARACTERISTICAS PRODUCTIVAS

ALBERTO BARRERAS SERRANO ALEJANDRO ANTONIO GONZALEZ SARABIA KARINA MEJIA MARTINEZ CLEMENTE LEMUS FLORES JAVIER GERMAN RODRIGUEZ CARPENA (2011)

The aim of this study was to compare the genetic variability and diversity, and genetic distances between Mexican Creole pigs – Pelón Mexicano (CPM) and Cuinos (CC) – with the commercial breed Yorkshire for the candidate genes CAST, DECR1, HAL, HFABP4, LEP, LIPE, MCR4, MYOG, RN and CHX, using the PCR-RFLP technique. One hundred eighty pigs (59 CPM, 65 CC and 56 Yorkshire) were evaluated. Gene and genotypic frequencies, heterozygosity, genetic distances and filogenetic trees between breed groups were analyzed. In the comparison among the three breeds, the allelic and genotypic frequencies were different for CAST, DECR1, HFABP4, LEP, MCR4 and CHX. For LIPE, CC pigs were similar to Yorkshire; while for MYOG, the CPM were similar to Yorkshire breeds. There were no differences in the genic and genotypic frequencies for HAL and RN genes between Creole and Yorkshire populations. The Yorkshire breed had higher favorable allele frequency for CAST, LIPE, MCR4 and MYOG, smaller for DECR1, HFABP4, and for CHX, and moderate for LEP genes. The heterozygosity average for all genes was higher in CPM (0.42±0.05) and similar in both the CC (0.33±0.06) and Yorkshire (0.35±0.05) breeds. In the estimation of genetic distances considering all genes, the CC breed are more distant from the Yorshire pigs.

El objetivo de este trabajo fue comparar la variabilidad, diversidad y distancias genéticas entre cerdos criollos, Pelón Mexicano (CPM) y Cuinos (CC), con Yorkshire, cuanto a los genes candidatos CAST, DECR1, HAL, HFABP4, LEP, LIPE, MCR4, MYOG, RN y CHX, a través de analysis por PCR-RFLP. Se evaluaron 180 cerdos: 59CPM, 65CC y 56Yorkshire. Se analizaron las frecuencias génicas y genotípicas, heterocigosidad, distancias genéticas y árboles filogenéticos entre grupos raciales. Para CAST, DECR1, HFABP4, LEP, MCR4 y CHX las frecuencias génicas y genotípicas fueron diferentes al comparar las tres razas. En LIPE, los CC fueron iguales a los Yorkshire; en cuanto a MYOG, los CPM fueron iguales a los Yorkshire. No hubo diferencias entre poblaciones criollas y Yorkshire en las frecuencias génicas y genotípicas para HAL y RN. Los cerdos Yorkshire presentaron mayor frecuencia en alelos favorables para CAST, LIPE, MCR4 y MYOG, menor frecuencia de DECR1, HFABP4, CHX, y moderada en LEP. La heterocigosidad promedio para todos los genes fue mayor en CPM (0,42±0,05) y similar en CC (0,33±0,06) y Yorkshire (0,35±0,05). Al calcular distancias genéticas con todos los genes, los CC se encuentran más distantes de los Yorkshire.

Article

calidad de la carne marcadores moleculares variación genética meat quality molecular markers genetic variation CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Unlocking the novel genetic diversity and population structure of synthetic Hexaploid wheat

Madhav Bhatta Alexey Morgounov Jesse Poland Peter Stephen Baenziger (2018)

Synthetic hexaploid wheat (shw) is a reconstitution of hexaploid wheat from its progenitors (triticum turgidum ssp. Durum l.; Aabb x aegilops tauschii coss.; Dd) and has novel sources of genetic diversity for broadening the genetic base of elite bread wheat (bw) germplasm (t. Aestivum l). Understanding the diversity and population structure of shws will facilitate their use in wheat breeding programs. Our objectives were to understand the genetic diversity and population structure of shws and compare the genetic diversity of shws with elite bw cultivars and demonstrate the potential of shws to broaden the genetic base of modern wheat germplasm. The genotyping-by-sequencing of shw provided 35,939 high-quality single nucleotide polymorphisms (snps) that were distributed across the a (33%), b (36%), and d (31%) genomes. The percentage of snps on the d genome was nearly same as the other two genomes, unlike in bw cultivars where the d genome polymorphism is generally much lower than the a and b genomes. This indicates the presence of high variation in the d genome in the shws. The d genome gene diversity of shws was 88.2% higher than that found in a sample of elite bw cultivars. Population structure analysis revealed that shws could be separated into two subgroups, mainly differentiated by geographical location of durum parents and growth habit of the crop (spring and winter type). Further population structure analysis of durum and ae. Parents separately identified two subgroups, mainly based on type of parents used. Although ae. Tauschii parents were divided into two sub-species: ae. Tauschii ssp. Tauschii and ssp. Strangulate, they were not clearly distinguished in the diversity analysis outcome. Population differentiation between shws (spring_shw and winter_shw) samples using analysis of molecular variance indicated 17.43% of genetic variance between populations and the remainder within populations. Shws were diverse and had a clearly distinguished population structure identified through gbs-derived snps. The results of this study will provide valuable information for wheat genetic improvement through inclusion of novel genetic variation and is a prerequisite for association mapping and genomic selection to unravel economically important marker-trait associations and for cultivar development.

Article

Genetic variation Hexaploidy Wheats Aegilops Tauschii D-Genome Diversity Genotype-By-Sequencing Single Nucleotide Polymorphism Bread Wheat AEGILOPS SOFT WHEAT TRITICUM TURGIDUM DNA SEQUENCE AGRICULTURAL SCIENCES AND BIOTECHNOLOGY CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA