Estrategias para la adaptación de la producción de maní al cambio climático y a la variabilidad climática en el sur de Córdoba

El cambio climático y la variabilidad climática ocasionan una variabilidad substancial en la producción y graves consecuencias sobre los agricultores, tanto en forma individual como sobre las economías regionales del centro de Argentina. El objetivo de este trabajo es evaluar, mediante la utilización del modelo de simulación de cultivos CROPGRO v3.5, el cambio en la fecha de siembra como estrategia de adaptación con el propósito de disminuir las posibles consecuencias negativas de la variabilidad y los cambios del clima sobre el cultivo de maní. Para la zona en estudio, que abarcó la mitad sur de la provincia de Córdoba, Argentina, se construyeron escenarios climáticos derivados de los Modelos de Circulación Global ECHAM4/OPY3 y HadCM3 y Escenarios de Emisiones A2 y B2 con y sin cambios en la concentración de CO2 para el año 2050. El adelantamiento de la fecha de siembra en 15 y 30 días produjo rendimientos más elevados al alargarse el ciclo del cultivo y por menor exposición a las heladas tempranas aunque no debe descartarse el efecto negativo de heladas al inicio de la estación de crecimiento. Los resultados obtenidos pueden proveer una visión de las posibles modificaciones que será necesario realizar en la producción agropecuaria de la región para ayudar a enfrentar los cambios futuros.Eje: Economía, producción y tecnología.Universidad Nacional de La Plat

Estrategias para la adaptación de la producción de maní al cambio climático y a la variabilidad climática en el sur de Córdoba

El cambio climático y la variabilidad climática ocasionan una variabilidad substancial en la producción y graves consecuencias sobre los agricultores, tanto en forma individual como sobre las economías regionales del centro de Argentina. El objetivo de este trabajo es evaluar, mediante la utilización del modelo de simulación de cultivos CROPGRO v3.5, el cambio en la fecha de siembra como estrategia de adaptación con el propósito de disminuir las posibles consecuencias negativas de la variabilidad y los cambios del clima sobre el cultivo de maní. Para la zona en estudio, que abarcó la mitad sur de la provincia de Córdoba, Argentina, se construyeron escenarios climáticos derivados de los Modelos de Circulación Global ECHAM4/OPY3 y HadCM3 y Escenarios de Emisiones A2 y B2 con y sin cambios en la concentración de CO2 para el año 2050. El adelantamiento de la fecha de siembra en 15 y 30 días produjo rendimientos más elevados al alargarse el ciclo del cultivo y por menor exposición a las heladas tempranas aunque no debe descartarse el efecto negativo de heladas al inicio de la estación de crecimiento. Los resultados obtenidos pueden proveer una visión de las posibles modificaciones que será necesario realizar en la producción agropecuaria de la región para ayudar a enfrentar los cambios futuros.Eje: Economía, producción y tecnología.Universidad Nacional de La Plat

Transferencias monetarias condicionadas e inclusión financiera en América Latina: una primera aproximación regional

The objective of this paper is to study the relationship between conditional cash transfer (CCT) and financial inclusion in Latin American countries. To achieve this objective, we use an unbalanced panel of 16 Latin American countries for the period 2003-2013. After accounting for country and time effects in a panel data model, our results show that the impact of CCT on financial inclusion is slight but positive and statistically significant. Our analysis then suggests a greater impact if the number of CCT offering financial services in the region increases. El objetivo de este trabajo es estudiar la relación entre las trasferencias monetarias condicionadas (CCT) y la inclusión financiera en América Latina. Para alcanzar dicho objetivo, se utilizó un panel no balanceado de 16 países para el periodo 2003-2013. Tras controlar por los efectos fijos de país y de tiempo en un modelo de datos de panel, nuestros resultados muestran que el impacto de las CCT en la inclusión financiera es leve pero positivo y estadísticamente significativo. Nuestro análisis sugiere entonces, un impacto mayor si el número de CCT que ofrecen servicios financieros en la región se incrementase

Equine protease inhibitor system as a marker for the diagnosis of chronic obstructive pulmonary disease (COPD).

Polymorphism in programming languages enables code reuse. Here, we show that polymorphism has broad applicability far beyond computations for technical computing: parallelism in distributed computing, presentation of visualizations of runtime data flow, and proofs for formal verification of correctness. The ability to reuse a single codebase for all these purposes provides new ways to understand and verify parallel programs.Comment: 10 pages, 3 figures. Proceedings of HPTCDL, the 1st Workshop on High Performance Technical Computing in Dynamic Languages, November 17, 2014, New Orleans, Louisiana, USA. Supporting Information available at http://jiahao.github.io/parallel-prefi

Intraspecfic variation in cold-temperature metabolic phenotypes of Arabidopsis lyrata ssp petraea

Atmospheric temperature is a key factor in determining the distribution of a plant species. Alongside this, plant populations growing at the margin of their range may exhibit traits that indicate genetic differentiation and adaptation to their local abiotic environment. We investigated whether geographically separated marginal populations of Arabidopsis lyrata ssp. petraea have distinct metabolic phenotypes associated with exposure to cold temperatures. Seeds of A. petraea were obtained from populations along a latitudinal gradient, namely Wales, Sweden and Iceland and grown in a controlled cabinet environment. Mannose, glucose, fructose, sucrose and raffinose concentrations were different between cold treatments and populations, especially in the Welsh population, but polyhydric alcohol concentrations were not. The free amino acid compositions were population specific, with fold differences in most amino acids, especially in the Icelandic populations, with gross changes in amino acids, particularly those associated with glutamine metabolism. Metabolic fingerprints and profiles were obtained. Principal component analysis (PCA) of metabolite fingerprints revealed metabolic characteristic phenotypes for each population and temperature. It is suggested that amino acids and carbohydrates were responsible for discriminating populations within the PCA. Metabolite fingerprinting and profiling has proved to be sufficiently sensitive to identify metabolic differences between plant populations at different atmospheric temperatures. These findings show that there is significant natural variation in cold metabolism among populations of A. l. petraea which may signify plant adaptation to local climates

Gene expression and metabolite profiling of Populus euphratica growing in the Negev desert

BACKGROUND: Plants growing in their natural habitat represent a valuable resource for elucidating mechanisms of acclimation to environmental constraints. Populus euphratica is a salt-tolerant tree species growing in saline semi-arid areas. To identify genes involved in abiotic stress responses under natural conditions we constructed several normalized and subtracted cDNA libraries from control, stress-exposed and desert-grown P. euphratica trees. In addition, we identified several metabolites in desert-grown P. euphratica trees. RESULTS: About 14,000 expressed sequence tag (EST) sequences were obtained with a good representation of genes putatively involved in resistance and tolerance to salt and other abiotic stresses. A P. euphratica DNA microarray with a uni-gene set of ESTs representing approximately 6,340 different genes was constructed. The microarray was used to study gene expression in adult P. euphratica trees growing in the desert canyon of Ein Avdat in Israel. In parallel, 22 selected metabolites were profiled in the same trees. CONCLUSION: Of the obtained ESTs, 98% were found in the sequenced P. trichocarpa genome and 74% in other Populus EST collections. This implies that the P. euphratica genome does not contain different genes per se, but that regulation of gene expression might be different and that P. euphratica expresses a different set of genes that contribute to adaptation to saline growth conditions. Also, all of the five measured amino acids show increased levels in trees growing in the more saline soil

Rising from the Sea: Correlations between Sulfated Polysaccharides and Salinity in Plants

High salinity soils inhibit crop production worldwide and represent a serious agricultural problem. To meet our ever-increasing demand for food, it is essential to understand and engineer salt-resistant crops. In this study, we evaluated the occurrence and function of sulfated polysaccharides in plants. Although ubiquitously present in marine algae, the presence of sulfated polysaccharides among the species tested was restricted to halophytes, suggesting a possible correlation with salt stress or resistance. To test this hypothesis, sulfated polysaccharides from plants artificially and naturally exposed to different salinities were analyzed. Our results revealed that the sulfated polysaccharide concentration, as well as the degree to which these compounds were sulfated in halophytic species, were positively correlated with salinity. We found that sulfated polysaccharides produced by Ruppia maritima Loisel disappeared when the plant was cultivated in the absence of salt. However, subjecting the glycophyte Oryza sativa Linnaeus to salt stress did not induce the biosynthesis of sulfated polysaccharides but increased the concentration of the carboxylated polysaccharides; this finding suggests that negatively charged cell wall polysaccharides might play a role in coping with salt stress. These data suggest that the presence of sulfated polysaccharides in plants is an adaptation to high salt environments, which may have been conserved during plant evolution from marine green algae. Our results address a practical biological concept; additionally, we suggest future strategies that may be beneficial when engineering salt-resistant crops

Prediction of Drought-Resistant Genes in Arabidopsis thaliana Using SVM-RFE

Background: Identifying genes with essential roles in resisting environmental stress rates high in agronomic importance. Although massive DNA microarray gene expression data have been generated for plants, current computational approaches underutilize these data for studying genotype-trait relationships. Some advanced gene identification methods have been explored for human diseases, but typically these methods have not been converted into publicly available software tools and cannot be applied to plants for identifying genes with agronomic traits. Methodology: In this study, we used 22 sets of Arabidopsis thaliana gene expression data from GEO to predict the key genes involved in water tolerance. We applied an SVM-RFE (Support Vector Machine-Recursive Feature Elimination) feature selection method for the prediction. To address small sample sizes, we developed a modified approach for SVM-RFE by using bootstrapping and leave-one-out cross-validation. We also expanded our study to predict genes involved in water susceptibility. Conclusions: We analyzed the top 10 genes predicted to be involved in water tolerance. Seven of them are connected to known biological processes in drought resistance. We also analyzed the top 100 genes in terms of their biological functions. Our study shows that the SVM-RFE method is a highly promising method in analyzing plant microarray data for studyin

Is callose a barrier for lead ions entering Lemna minor L. root cells?

Plants have developed a range of strategies for resisting environmental stresses. One of the most common is the synthesis and deposition of callose, which functions as a barrier against stress factor penetration. The aim of our study was to examine whether callose forms an efficient barrier against Pb penetration in the roots of Lemna minor L. exposed to this metal. The obtained results showed that Pb induced callose synthesis in L. minor roots, but it was not deposited regularly in all tissues and cells. Callose occurred mainly in the protoderm and in the centre of the root tip (procambial central cylinder). Moreover, continuous callose bands, which could form an efficient barrier for Pb penetration, were formed only in the newly formed and anticlinal cell walls (CWs); while in other CWs, callose formed only small clusters or incomplete bands. Such an arrangement of callose within root CWs inefficiently protected the protoplast from Pb penetration. As a result, Pb was commonly present inside the root cells. In the light of the results, the barrier role of callose against metal ion penetration appears to be less obvious than previously believed. It was indicated that induction of callose synthesis is not enough for a successful blockade of the stress factor penetration. Furthermore, it would appear that the pattern of callose distribution has an important role in this defence strategy