Quantitative trait locus mapping associated with earliness and fruit weight in tomato

The flowering time is regarded as an important factor that affects yield in various crops. In order to understand how the molecular basis controlling main components of earliness in tomato (Solanum lycopersicum L.), and to deduce whether the correlation between fruit weight, days to flowering and seed weight, is caused by pleiotropic effects or genetic linkage, a QTLs analysis was carried out using an F2 interspecific population derived from the cross of S. lycopersicum and S. pimpinellifolium. The analysis revealed that most of the components related to earliness were independent due to the absence of phenotypic correlation and lack of co-localization of their QTLs. QTLs affecting the flowering time showed considerable variation over time in values of explained phenotypic variation and average effects, which suggested dominance becomes more evident over time. The path analysis showed that traits such as days to flowering, seed weight, and length of the first leaf had a significant effect on the expression of fruit weight, confirming that their correlations were due to linkage. This result was also confirmed in two genomic regions located on chromosomes 1 and 4, where despite showing high co-localization of QTLs associated to days to flowering, seed weight and fruit weight, the presence and absence of epistasis in dfft1.1 × dftt4.1 and fw1.1 × fw4.1, suggested that the linkage was the main cause of the co-localization

Validation of QTL HAP-6A-13 associated with grain weight in spring bread wheats

Este estudio se realizó para validar el locus de carácter cuantitativo (QTL- quantitative trait locus) HAP-6A-13, el cual fue reportado con asociación a peso de grano en trigos harineros de primavera del Centro Internacional de Mejoramiento de Maíz y Trigo (CIMMYT). Para realizar la validación se diseñaron dos marcadores de competencia alelo específica (KASP- kompetitive allele specific PCR) para los polimorfismos de un solo nucleótido (SNP) T/C y A/G integrados en el QTL. La asociación de los marcadores KASP con el peso de mil granos y rendimiento se verificó mediante estudio de asociación del genoma completo (GWAS) en cuatro colecciones de trigo. Los dos marcadores KASP mostraron asociación significativa con el peso de mil granos y rendimiento (P ≤ 0.05); adicionalmente, se generaron 10 familias endogámicas heterogéneas (HIF-heterogeneous inbred families) y se evaluó el peso de mil granos, rendimiento y otros caracteres morfométricos del grano. En contraste con los resultados de GWAS, en las evaluaciones de las HIF el efecto del QTL HAP-6A-13 fue significativo (P ≤ 0.05) sólo en una HIF para peso de mil granos y en tres HIF para longitud de grano, lo que demuestra la dificultad de validar un QTL de efecto menor en trigo

Route Analysis Through Filial Generations of Modern Varieties of Tomato (Solanum lycopersicum L.)

In Mexico, to reduce production costs, small producers use tomato seeds of advanced generations such as F2 and F3. The objectives of this study were to measure the efficiency of using advanced populations of some commercial tomato hybrids and to identify the most important yield components associated with yield. Seven saladette-type hybrids of indeterminate growth were evaluated, as well as their respective generations F2s and F3s under greenhouse conditions. The evaluation of the three generations was carried out during the 2013 agricultural cycle. Three harvests were made at 82, 94 and 136 days after transplanting. The experiment was carried out under a randomized complete block experimental design, with 4 replications and 10 individuals per repletion. The obtained results indicated that there were significant differences for few traits in F2 and F3. Path analysis showed that the total number of fruits had the highest direct and indirect effects on yield through generations. Based on our analysis, the advanced generations of ‘LORETO’, ‘CUAUHTÉMOC’ and ‘ESPARTACO’ could be used by the small growers since low values of inbreeding depression was observed in F2 and F3.Objective: To measure the efficiency of using advanced generations of some commercial tomato hybrids for small farmers and to identify the most important yield components associated with yield. Design/Methodology/Approach: Seven saladette-type hybrids of indeterminate growth were evaluated, as well as their respective generations F2s and F3s under greenhouse conditions. The evaluation of the three generations was carried out during the 2013 agricultural cycle. Three harvests were made at 82, 94 and 136 days after transplanting. The experiment was a randomized complete block design, with 4 replications and 10 plants per replication. Results: Results indicated that there were significant differences for a few traits in F2 and F3. Path analysis showed that the total number of fruits had the highest direct and indirect effects on yield through generations. Limitations of the study/implications: The usefulness of advanced generations of tomato commercial hybrids would depend on the genetic background of the parental lines that take part in such as hybrids, as some hybrids would present high inbreeding depression depending on the genetic composition of their progenitors. Findings/Conclusions: Advanced generations of ‘LORETO’, ‘CUAUHTÉMOC’ and ‘ESPARTACO’ could be used by the small growers since low values of inbreeding depression were observed in F2 and F3 familie

A greve, o carnaval e os comícios: O mundo do trabalho portuário em Buenos Aires e a configuração de uma comunidade obreira, verão de 1904

Objetivo/contexto: El presente trabajo indaga sobre el proceso de configuración de una comunidad obrera en el puerto de Buenos Aires, resultado de la acción de los trabajadores y habitantes del barrio obrero a inicios del siglo XX. Originalidad: En el cruce de diversas historiografías (historia social, cultural y política), aquí se propone mirar de manera conjunta la dimensión laboral, la conflictividad obrera, el tiempo de la fiesta o carnaval y la participación electoral, para pensar, desde esta multiplicidad de eventos y experiencias, la aparición de una comunidad obrera radicalizada y con una particular identificación gestada en la movilización durante una época específica a comienzos del siglo XX. Metodología: A partir de una coyuntura significativa, como fueron los meses de fines de 1903 e inicios de 1904 en el barrio portuario, y basado en un variado conjunto de documentos (periódicos comerciales, barriales, gremiales, de las izquierdas, revistas de actualidad, informes policiales, fotografías, entre otros), el artículo reconstruye la experiencia obrera en los escenarios de la protesta, el carnaval y la votación para diputados celebrada durante ese verano. Al mismo tiempo, se ponderan aquí la dimensión territorial de la configuración comunitaria y los lugares centrales de la trama conformada por la protesta, la fiesta y las elecciones. Conclusiones: El análisis permite identificar que las sociabilidades obreras en el puerto consolidaron una comunidad, afincada en solidaridades familiares, corporativas, partidistas y vecinales obreras, en tiempos de movilización gremial, política y festiva, y de confrontación radicalizada con el Estado y las empresas.Objective/context: This paper inquires about the process of emergence of a working-class community in the port of Buenos Aires, resulting from actions by workers and inhabitants of the working-class neighborhood at the beginning of the 20th century. Originality: At the crossroads of diverse historiographies (social, cultural and political history), this paper proposes a joint regard at the labor dimension, worker disputes, carnival celebrations and electoral participation, and to use this multiplicity of events and experiences to think about the emergence of a radicalized worker community, with a particular identity gestated in the mobilization during a specific time at the beginning of the 20th century. Methodology: The months from late 1903 to early 1904 were an important juncture in the port district, and based on a diverse set of documents (commercial, neighborhood, trade and left-wing newspapers, news magazines, police reports, photographs, among others), this paper reconstructs the worker experience in three settings converging in the summer months: protest, carnival and legislative polls. At the same time, it ponders the territorial dimension of community configuration and the key places that formed the backdrop to a story of protest, celebration, and elections. Conclusions: This analysis shows us that worker sociabilities around the port consolidated a community based on family, corporate, partisan, neighborhood and worker solidarities, in times of labor, political and festive mobilization, and of radicalized confrontation with the State and with corporations.Objetivo/contexto: O presente trabalho indaga sobre o processo de configuração de uma comunidade obreira no porto de Buenos Aires, resultado da ação dos trabalhadores e habitantes do bairro obreiro no início do século XX. Originalidade: No cruzamento de diversas historiografias (história social, cultural e política), propõe-se aqui observar, de maneira conjunta, a dimensão laboral, a conflituosidade obreira, o tempo da festa ou carnaval e a participação eleitoral para pensar, a partir dessa multiplicidade de eventos e experiências, a aparição de uma comunidade obreira radicalizada e com uma identificação particular gestada na mobilização durante uma época específica no começo do século XX. Metodologia: A partir de uma conjuntura significativa, como foi o final de 1903 e início de 1904 no bairro portuário e baseado em um variado conjunto de documentos (jornais comerciais, de bairros, de grêmios, das esquerdas, revistas de atualidades, relatórios policiais, fotografias, entre outros), o artigo reconstrói a experiência obreira nos cenários do protesto, do carnaval e da votação para deputados celebrada nesse verão. Ao mesmo tempo, ponderam-se aqui a dimensão territorial da configuração comunitária e os lugares centrais da trama formada pelo protesto, pela festa e pelas eleições. Conclusões: A análise permite identificar que as sociabilidades obreiras no porto consolidaram uma comunidade, estabelecida em solidariedades familiares, corporativas, partidaristas e de vizinhanças obreiras, em tempos de mobilização gremial, política e festiva, e de confronto radicalizado com o Estado e com as empresas.Fil: Caruso, Laura Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Martin. Instituto de Altos Estudios Sociales. Centro de Estudios de Historia E Historia del Arte.; Argentin

Marker development for quality protein maize breeding and an interaction study between Opaque-2 and Ask2 genes

Quality Protein Maize (QPM) kernels contain twice the amounts of lysine and tryptophan compared to normal corn kernels. Although the opaque-2 (o2) mutation is the underlying cause of this beneficial change, other genes such as Aspartate kinase-2 (Ask2) affect the amino acid content in the endosperm to a lesser degree. To date, reports on the interaction between both loci are scarce and there are no high-throughput assays for the identification of the alleles of these genes. The objectives of this research were: 1) to study the interaction between the o2 and Ask2 genes with respect to the accumulation of amino acids in the endosperm in an F2 population, 2) to identify conserved SNPs into the o2 gene that can be used as markers, 3) to estimate the frequency of an SNP of Ask2 associated with the accumulation of lysine in the endosperm in CIMMYT germplasm, and 4) to develop high-throughput marker assays for these SNPs. The interaction study showed a preponderant effect of o2 on the accumulation of 11 amino acids (P ≤ 0.01). Ask2 appeared only to act with o2 to enhance marginally lysine, histidine and methionine levels in the double recessive homozygotes. Sequencing of amplicons at the o2 locus led to the identification of an SNP in exon 1 that discriminated all QPM (C) genotypes from non-QPM (T) genotypes. Validation of this SNP through KASP™ assays indicated that it was 92 % assertive in differentiating the o2 genotypes. In contrast, the frequency of the Ask2 SNP in CIMMYT QPM germplasm was low; however, an SSCP marker developed using this SNP detected five variants indicating that other unknown base changes may confer positive lysine-increasing responses. These markers could aid the marker-assisted selection of QPM cultivars

Quantitative trait locus mapping associated with earliness and fruit weight in tomato

ABSTRACT The flowering time is regarded as an important factor that affects yield in various crops. In order to understand how the molecular basis controlling main components of earliness in tomato (Solanum lycopersicum L.), and to deduce whether the correlation between fruit weight, days to flowering and seed weight, is caused by pleiotropic effects or genetic linkage, a QTLs analysis was carried out using an F2 interspecific population derived from the cross of S. lycopersicum and S. pimpinellifolium. The analysis revealed that most of the components related to earliness were independent due to the absence of phenotypic correlation and lack of co-localization of their QTLs. QTLs affecting the flowering time showed considerable variation over time in values of explained phenotypic variation and average effects, which suggested dominance becomes more evident over time. The path analysis showed that traits such as days to flowering, seed weight, and length of the first leaf had a significant effect on the expression of fruit weight, confirming that their correlations were due to linkage. This result was also confirmed in two genomic regions located on chromosomes 1 and 4, where despite showing high co-localization of QTLs associated to days to flowering, seed weight and fruit weight, the presence and absence of epistasis in dfft1.1 × dftt4.1 and fw1.1 × fw4.1, suggested that the linkage was the main cause of the co-localization

How do people understand the causes of poverty and wealth? A revised structural dimensionality of the attributions about poverty and wealth scales

The attributional process, defined as the process of inferring the causes of the events that surround individuals in their daily lives, can potentially shape the understanding of poverty and wealth. For instance, it might influence how people behave, what they expect from poor and wealthy groups in their society, and how they judge them. However, the existing measures that capture these attributional phenomena have several limitations. Some attributional factors lack empirical support, or some implemented items lack relevance in contemporary society. Therefore, the present study is aimed to deepen the understanding of the attributional process by reviewing the factor structure of the poverty (Cozzarelli et al, 2001) and wealth attribution scales (Bullock et al, 2003), as well as adapting and verifying the validity of these scales among the Mexican population. To do so, we revised the factor structure of the poverty and wealth attribution scales to create a unified scale. We back-translated the original items, conducted exploratory and confirmatory analyses, restructured the scale’s factors, and related them with other covariates. Our results indicate that these scales uniquely differentiate between internal and external attributions, demonstrating that the new factor structure is better for measuring attributional processes regarding the perceived causes of poverty and wealth than those used in previous research.UCR::Sedes Regionales::Sede de Occidente::Recinto San Ramó

Diagnóstico ecológico para la conservación de Jatropha spp. (Euphorbiaceae) y sus hábitats, en la Reserva Tehuacán-Cuicatlán, México

Jatropha spp., es un importante recurso fitogenético usado como alimento, medicina y biocombustible. En este estudio verificamos la identidad taxonómica de las especies de Jatropha para la Reserva de la Biosfera Tehuacán-Cuicatlán, y las unidades ambientales (UA) que ocupan. Evaluamos el estado de conservación de sus hábitats y la vulnerabilidad de las poblaciones de Jatropha. Los sitios de muestreo seleccionados en la Reserva fueron 15. El trabajo taxonómico estuvo basado en especímenes, descripciones originales y material tipo de herbarios y aquellos en línea. Las UA fueron clasificadas mediante variables biofísicas y el software gvSIG. Los atributos ecológicos fueron determinados con análisis cuantitativo por el método de cuadrado centrado en un punto; el disturbio fue estimado a través de indicadores de sitio, y el estado de conservación de las poblaciones de Jatropha con el Método para la Evaluación de Riesgo de Extinción de Plantas en México (MER). Jatropha frecuentemente dominó la fisonomía de las comunidades vegetales. La distribución actual de las especies de Jatropha en la Reserva estuvo principalmente determinada por las variables altitud, temperatura y precipitación. Las especies confirmadas fueron: Jatropha ciliata Sessé ex Cerv., Jatropha neopauciflora Pax, Jatropha oaxacana J. Jiménez Ram. & R. Torres, Jatropha rufescens Brandegee, y Jatropha rzedowskii J. Jiménez Ram., las cuales estuvieron distribuidas en cuatro de las seis UA definidas. J. neopauciflora y J. rzedowskii son las especies más ampliamente distribuidas; estas últimas especies concurrieron en cuatro, J. oaxacana en dos, mientras que J. rufescens y J. ciliata en una UA, siendo ésta la especie más restringida. La riqueza de géneros en las comunidades asociadas varió entre 16 y 42. Los máximos y mínimos Índices de Valores de Importancia fueron observados en San Nicolás Tepoxtitlan para J. neopauciflora (53.75%) y J. rzedowskii (1.50%). El índice de disturbio varió entre 0.22 y 0.82, con promedio de 0.51, mientras que la variable ganado tuvo mayor contribución. Considerando las categorías de riesgo del MER, concluimos que J. oaxacana requiere protección especial, mientras que J. ciliata y J. rufescens fueron especies en riesgo de extinción. El estado de conservación de los hábitats ocupados por poblaciones de Jatropha spp. es moderado, tomando en cuenta la tasa de disturbio. Los principales factores que afectan a los hábitats de Jatropha son el ganado y las actividades humanas; la composición florística de las comunidades vegetales tuvo baja riqueza. Estos resultados apoyan la necesidad de establecer estrategias de conservación para evitar la pérdida de importantes poblaciones silvestres de Jatropha

Caracterización estomática de cinco especies del género Vanilla.

The objective was to characterize the stomata of five species of vanilla. Throughout 2012, leaf samples of V. planifolia G. Jackson, V. pompona Schiede, V. indora Schiede, V. insignis Ames and V. odorota Presl were taken from the vanilla germplasm bank at the Benemérita Universidad Autónoma de Puebla. The stomata size was obtained considering their length and width, as well as the index and stomata number of the abaxial and adaxial leaf surfaces in a randomized complete block design with three replications. V. pompona Schiede and V. inodora Schiede showed the highest stomatal index with 8713 and 8246 stomata per mm2, respectively, followed by V. odorata Presl with 4412 stomata per mm2. V. insignis Ames and V. planifolia G. Jackson showed the lowest stomata index with 2968 and 1378 stomata per mm2, respectively, in the abaxial leaf surface, these differences were statistically significant (P≤0.05). According to the position of the leaf stomata, V. planifolia G. Jackson and V. inodora Schiede can be considered to be hypostomatics since they showed stomata only in the abaxial leaf surface. V. insignis Ames, V. inodora Schiede and V. odorata Presl. can be considered to be anfiestomatic because they showed stomata in both the abaxial and adaxial leaf surfaces. V. inodora Schiede had smaller stomata compared with the other species.That is an important feature to be included in the genetic improvement of the genus Vanilla, because due to climate change, temperature will increase and precipitation will decrease, so Vainilla will require more efficient genotypes for water use.El objetivo de este estudio fue caracterizar los estomas de cinco especies de vainilla. Durante el año 2012 se tomaron muestras de hoja de Vanilla planifolia G. Jackson, V. pompona Schiede, V. inodora Schiede, V. insignis Ames y V. odorata Presl, del banco de germoplasma de vainilla de la Benemérita Universidad Autónoma de Puebla. Se obtuvo el tamaño de estomas al considerar el largo y ancho de estos, índice y número estomático de la parte abaxial y adaxial de la hoja, en un diseño de bloques completos al azar con tres repeticiones. V. pompona Schiede y V. inodora Schiede presentaron mayor índice estomático con 8713 y 8246 estomas por mm2, respectivamente, seguido por V. odorata Presl con 4412 estomas por mm2. V. insignis Ames y V. planifolia G. Jackson tuvieron el menor índice estomático con 2968 y 1378 estomas por mm2, respectivamente, en la superficie abaxial de la hoja, diferencias que fueron estadísticamente significativas (p≤ 0,05). Por la posición de los estomas en la hoja, V. planifolia G. Jackson y V. pompona Schiede se pueden considerar hipoestomáticas por presentar estomas solamente en la parte abaxial de la hoja. V. insignis Ames, V. inodora Schiede y V. odorata Presl se pueden considerar anfiestomáticas por presentar estomas en la parte abaxial y adaxial de la hoja. V. inodora Schiede presentó estomas más pequeños en comparación con las demás especies, característica importante para ser integrada en el mejoramiento genético del género Vanilla, al considerar el cambio climático, donde el aumento de temperatura y disminución de la precipitación requieren de genotipos con mayor eficiencia en el uso de agua