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La investigación tiene como objetivo implementar el enfoque de producción social del hábitat (PSH) en la construcción de la vivienda “Guenda Racaneé Saá” (ayuda mutua en lengua zapoteca) para una familia afectada durante los sismos del 2017 en el Istmo de Oaxaca, México. La metodología se adaptó de la propuesta de intervención comunitaria de Mori que la plantea en cuatro fases; diagnóstico, planeación, implementación y evaluación. En este trabajo se reportan los resultados del diagnóstico, que comprendió la caracterización del sitio, los agentes y la familia beneficiada del proyecto. Para la recolección de los datos se emplearon técnicas de la metodología etnográfica como observación simple, participativa, fotoetnografía y entrevistas. Se identificó que las condiciones del sitio son favorables para implementar el proyecto, así como la disposición de actores (academia, organización civil y familia beneficiada) para aportar soluciones técnicas y de gestión social. Se concluye que aplicando el enfoque PSH se pueden solucionar problemas del hábitat afectado por desastres naturales como los sismos tan frecuentes en el sur de México.

El aprovechamiento de la biomasa con fines energéticos es una alternativa atractiva para reducir la dependencia de los combustibles fósiles y su impacto ambiental. En este sentido, la ubicación geográfica de los sitios de producción y consumo de biomasa, su logística, así como la planificación de la cadena productiva, son factores indispensables para la evaluación y puesta en marcha de proyectos biomásicos con fines energéticos. Aunque diversos estudios han abordado estos problemas de forma separada, son pocos los trabajos que integran todos estos aspectos. En este trabajo se describe la integración de una serie de análisis espaciales, con un modelo matemático para la optimización de costos de transporte entre diferentes nodos de la cadena productiva de la biomasa. Mediante un caso de estudio y el análisis de diferentes escenarios de oferta y demanda, se evalúa el funcionamiento del módulo de optimización. Los resultados obtenidos permiten estimar de manera óptima la distribución de biomasa desde diferentes centros de oferta (nodos de almacenamiento), hacia diferentes usuarios (nodos de demanda), tomando al costo de transporte como función objetivo. La distribución óptima de biomasa permite planificar su uso para diferentes regiones de interés a nivel nacional.

Aquaculture is considered the fastest-growing food supply, invertebrates being a key element; in particular, whiteleg shrimp (Litopenaeus vannamei). They contribute to human welfare, albeit potenti...

El ovino de pelo criollo (OPC) es un recurso zoogenético de gran importancia para Colombia, no existen programas de mejoramiento genético en el OPC, por lo que los cruzamientos absorbentes son los más comunes con el fin de aumentar la prolificidad. No se han estudiado los genes con efecto mayor sobre la prolificidad en el OPC, por lo que el objetivo de esta investigación fue caracterizar el polimorfismo genético en el locus FecXR del gen BMP15 y los loci FecGH y FecGI del gen GDF9. Para ello, se genotiparon 150 ovinos por PCR directa para el locus FecXR y por PCR-RFLP para los loci FecGH y FecGI. Se estimaron las frecuencias genotípicas y alélicas, se calculó la heterocigocidad observada (Ho) y esperada (He), los valores de F, el equilibrio de Hardy-Weinberg (EHW) y un análisis de varianza molecular (AMOVA). Los loci FecXR y FecGH fueron monomórficos, solo se encontró el genotipo y alelo silvestre en cada uno. El locus FecGI presentó frecuencias de 0,76 y 0,24 en los genotipos GG y GA, respectivamente. No se encontró el genotipo AA. Las frecuencias alélicas fueron G = 0,89 y A = 0,11. Las frecuencias aquí presentadas concuerdan con varios reportes en razas al rededor del mundo. La Ho fue mayor (0,226±0,15) que la He (0,189±0,12), con exceso de heterocigotos dentro (FIS = -0,127, p>0,05) y entre los rebaños (FIT = -0,119, p>0,05). La variación entre rebaños fue baja (1%) y el FST fue de 0,008 (p>0,05). La población se encontró en EHW. Este es el primer reporte de estos polimorfismos en el OPC que podrían ser utilizados en esquemas de selección para mejorar la prolificidad en esta raza.

The plant VQ motif-containing proteins are a recently discovered class of plant regulatory proteins interacting with WRKY transcription factors capable of modulate their activity as transcriptional regulators. The short VQ motif (FxxhVQxhTG) is the main element in the WRKY-VQ interaction, whereas a newly identified variable upstream amino acid motif appears to be determinant for the WRKY specificity. The VQ family has been studied in several species and seems to play important roles in a variety of biological processes, including response to biotic and abiotic stresses. Here, we present a systematic study of the VQ family in both diploid (Fragaria vesca) and octoploid (Fragaria x ananassa) strawberry species. Thus, twenty-five VQ-encoding genes were identified and twenty-three were further confirmed by gene expression analysis in different tissues and fruit ripening stages. Their expression profiles were also studied in F. ananassa fruits affected by anthracnose, caused by the ascomycete fungus Colletotrichum, a major pathogen of strawberry, and in response to the phytohormones salicylic acid and methyl-jasmonate, which are well established as central stress signals to regulate defence responses to pathogens. This comprehensive analysis sheds light for a better understanding of putative implications of members of the VQ family in the defence mechanisms against this major pathogen in strawberry.

PACLOBUTRAZOL RESISTANCE (PRE) genes code atypical HLH transcriptional regulators characterized by the absence of a DNA-binding domain but present an HLH dimerization domain. In vegetative tissues, the function of these HLH proteins has been related with cell elongation processes. In strawberry, three FaPRE genes are expressed, two of them (FaPRE2 and FaPRE3) in vegetative tissues while FaPRE1 is fruit receptacle-specific. Ubiquitous FaPRE1 accumulation produced elongated flower receptacles and plants due to the elongation of the main aerial vegetative organs, with the exception of leaves. Histological analysis clearly demonstrated that the observed phenotype was due to significant changes in the parenchymal cell's morphology. In addition, transcriptomic studies of the transgenic elongated flower receptacles allowed to identify a small group of differentially expressed genes that encode cell wall-modifying enzymes. Together, the data seem to indicate that, in the strawberry plant vegetative organs, FaPRE proteins could modulate the expression of genes related with the determination of the size and shape of the parenchymal cells.

Background In soft fruits, the differential expression of many genes during development and ripening is responsible for changing their organoleptic properties. In strawberry fruit, although some genes involved in the metabolic regulation of the ripening process have been functionally characterized, some of the most studied genes correspond to transcription factors. High throughput transcriptomics analyses performed in strawberry red receptacle (Fragaria x ananassa) allowed us to identify a ripening-related gene that codes an atypical HLH (FaPRE1) with high sequence homology with the PACLOBUTRAZOL RESISTANCE (PRE) genes. PRE genes are atypical bHLH proteins characterized by the lack of a DNA-binding domain and whose function has been linked to the regulation of cell elongation processes. Results FaPRE1 sequence analysis indicates that this gene belongs to the subfamily of atypical bHLHs that also includes ILI-1 from rice, SlPRE2 from tomato and AtPRE1 from Arabidopsis, which are involved in transcriptional regulatory processes as repressors, through the blockage by heterodimerization of bHLH transcription factors. FaPRE1 presented a transcriptional model characteristic of a ripening-related gene with receptacle-specific expression, being repressed by auxins and activated by abscisic acid (ABA). However, its expression was not affected by gibberellic acid (GA3). On the other hand, the transitory silencing of FaPRE1 transcription by agroinfiltration in receptacle produced the down-regulation of a group of genes related to the ripening process while inducing the transcription of genes involved in receptacle growth and development. Conclusions In summary, this work presents for the first time experimental data that support an important novel function for the atypical HLH FaPRE1 during the strawberry fruit ripening. We hypothesize that FaPRE1 modulates antagonistically the transcription of genes related to both receptacle growth and ripening. Thus, FaPRE1 would repress the expression of receptacle growth promoting genes in the ripened receptacle, while it would activate the expression of those genes related to the receptacle ripening process.

Plant nonspecific lipid transfer proteins (nsLTPs) are widely distributed through plant kingdom and are characterized by the presence of a central hydrophobic cavity, suitable for binding various hydrophobic molecules. Despite extensive research on nsLTP in different plant species, mostly angiosperm, and the great diversity of physiological processes in which they seem to be involved, their exact functions still remain unclear. Also, very limited experimental data are available on nsLTP in gymnosperm. In this study, we report for the first time on the molecular cloning of nsLTP, from Pinus sylvestris L. (PsLTP1, GenBank accession JN980402.1) and the expression pattern of PsLTP1 during ontogenesis and in response to environmental stress conditions. Total RNA from roots of 7-day old pine seedlings was used to isolate the cDNA clone, corresponding to Scots pine lipid transfer protein. The open reading frame of PsLTP1 consists of 372 bp encoding a protein of 123 amino acids. Amino acid sequence alignment revealed that mature PsLTP1 shares high level of similarity with nsLTP from other conifers and with well-studied nsLTPs from angiosperms. The PsLTP1 contains a 27-amino-acid N-terminal signal sequence and presents all the features of a plant nsLTP. Amino acid comparison analysis and 3D structure prediction showed that PsLTP1 is a type 1 nsLTP. The results of the expression analysis of Scots pine PsLTP1 gene revealed that its transcripts accumulate in actively growing tissues. Furthermore, transcription of PsLTP1 was upregulated in response to cold and salt treatments, and downregulated during acidic, osmotic and water stresses.

Only a few transcription factors have been described in the regulation of the strawberry (Fragaria x ananassa) fruit ripening process. Using a transcriptomic approach, we identified and functionally characterized FaDOF2, a DOF-type ripening-related transcription factor, which is hormonally regulated and specific to the receptacle, though high expression levels were also found in petals. The expression pattern of FaDOF2 correlated with eugenol content, a phenylpropanoid volatile, in both fruit receptacles and petals. When FaDOF2 expression was silenced in ripe strawberry receptacles, the expression of FaEOBII and FaEGS2, two key genes involved in eugenol production, were down-regulated. These fruits showed a concomitant decrease in eugenol content, which confirmed that FaDOF2 is a transcription factor that is involved in eugenol production in ripe fruit receptacles. By using the yeast two-hybrid system and bimolecular fluorescence complementation, we demonstrated that FaDOF2 interacts with FaEOBII, a previously reported regulator of eugenol production, which determines fine-tuning of the expression of key genes that are involved in eugenol production. These results provide evidence that FaDOF2 plays a subsidiary regulatory role with FaEOBII in the expression of genes encoding enzymes that control eugenol production. Taken together, our results provide new insights into the regulation of the volatile phenylpropanoid pathway in ripe strawberry receptacles.

The protection of author's rights in Mexico has historical references to the Colonial Period, because the Spanish legal system established our legal foundations. Protection was granted during the author's life plus thirty years after his death, at which time his successors became entitled to royalties. Protection under Mexican law is obtained merely from the creation of the intellectual work itself, and no further step or formality is necessary. For some commentators, the publication of the said Decree meant the recognition that author's rights protection extended to computer software. In 1846, a Decree on Literary Property was enacted, treating author's rights as property rights, but limiting them in time to the author's life plus thirty years. The rights inherent in the person cannot be the subject of property rights because they have no value or economic importance, being non-commercial, not unlike the right of individual freedom, the right to life, and freedom of thought and expression.

Strawberry (Fragaria ×ananassa) is a major food crop worldwide, due to the flavor, aroma and health benefits of the fruit, but its productivity and quality are seriously limited by a large variety of phytopathogens, including Colletotrichum spp. So far, key factors regulating strawberry immune response remain unknown. The FaWRKY1 gene has been previously proposed as an important element mediating defense responses in strawberry to Colletotrichum acutatum. To get further insight into the functional role that FaWRKY1 plays in the defense mechanism, Agrobacterium-mediated transient transformation was used both to silence and overexpress the FaWRKY1 gene in strawberry fruits (Fragaria ×ananassa cv. Primoris), which were later analyzed upon C. acutatum inoculation. Susceptibility tests were performed after pathogen infection comparing the severity of disease between the two agroinfiltrated opposite halves of the same fruit, one half bearing a construct either for FaWRKY1 overexpression or RNAi-mediated silencing and the other half bearing the empty vector, as control. The severity of tissue damage was monitored and found to be visibly reduced at five days after pathogen inoculation in the fruit half where FaWRKY1 was transiently silenced compared to that of the opposite control half and statistical analysis corroborated a significant reduction in disease susceptibility. Contrarily, a similar level of susceptibility was found when FaWRKY1 overexpression and control fruit samples, was compared. These results unravel a negative regulatory role of FaWRKY1 in resistance to the phytopathogenic fungus C. acutatum in strawberry fruit and contrast with the previous role described for this gene in Arabidopsis as positive regulator of resistance against the bacteria Pseudomonas syringae. Based on previous results, a tentative working model for WRKY75 like genes after pathogen infection is proposed and the expression pattern of potential downstream FaWRKY1 target genes was also analyzed in strawberry fruit upon C. acutatum infection. Our results highlight that FaWRKY1 might display different function according to species, plant tissue and/or type of pathogen and underline the intricate FaWRKY1 responsive defense regulatory mechanism taking place in strawberry against this important crop pathogen., This work was supported by Junta de Andalucía, Spain (Proyectos de Excelencia P12-AGR2174, and grants to Grupo-BIO278).

In the last years, people has become aware of energy saving and thermal comfort requirements for home buildings in hot and cold seasons. In the present study, hybrid multifunctional constructive components made of a reinforced mortar channel filled with cement–soil–sawdust (CL2MSCAL) were evaluated to experimentally determine their thermal performance (thermal conductivity, thermal time lag and decrement factor). The experimental analysis performed in this study was based on dynamic climatology. Measurements of components surface temperature were conducted to determine temperature damping and temperature wave lag. Monthly average temperature and direct solar radiation data of the site was considered. Measurements of real-scale constructive components were conducted on a fully equipped thermal conductive system and thermal chambers (test cells) built for this purpose. Results are compared to concrete components (CCL) that account for approximately 71.6% of the houses built in Mexico and 43.2% in Oaxaca and reinforced mortar (CML) used as prefabricated housing systems. Best results were found for component CL2MSCAL that has a thermal conductivity of 0.81 W·m−1·K−1, a thermal damping of 81.5% (decrement factor of 0.166) and time lag of 7:37 h compared to CCL that present a time lag of 1 h and decrement factor of 0.9. Thus, it is concluded that CL2MSCAL roofing channel components are an alternative for energy saving and thermal comfort.

Uno de los materiales más usados como biomaterial es el acero 316LVM, sin embargo, presenta complicaciones al trabajarlo como reemplazo permanente, debido a que libera iones metálicos a los tejidos, generando aumento en el número de intervenciones que deben realizarse, ante esto, se estudia cómo mejorar el comportamiento de materiales convencionales mediante recubrimientos que elevan sus propiedades mecánicas y anticorrosivas, incrementando su vida útil. Se evaluó el comportamiento ante el fenómeno de micro-abrasión-corrosión de recubrimientos DLC/Si depositados mediante la técnica de deposición química de vapor asistida por plasma en contacto con solución de Ringer, simulando un ambiente biológico. Los resultados indican que el recubrimiento experimenta un aumento en el volumen de desgaste cuando se encuentra sometido al mecanismo de micro-abrasión-corrosión en relación con la prueba de solo microabrasión, además, la pérdida más significativa se encuentra en el sustrato sin recubrimiento, esto demuestra el efecto protector del recubrimiento.

NAC proteins are a family of transcription factors which have a variety of important regulatory roles in plants. They present a very well conserved group of NAC subdomains in the N-terminal region and a highly variable domain at the C-terminus. Currently, knowledge concerning NAC family in the strawberry plant remains very limited. In this work, we analyzed the NAC family of Fragaria vesca, and a total of 112 NAC proteins were identified after we curated the annotations from the version 4.0.a1 genome. They were placed into the ligation groups (pseudo-chromosomes) and described its physicochemical and genetic features. A microarray transcriptomic analysis showed six of them expressed during the development and ripening of the Fragaria x ananassa fruit. Their expression patterns were studied in fruit (receptacle and achenes) in different stages of development and in vegetative tissues. Also, the expression level under different hormonal treatments (auxins, ABA) and drought stress was investigated. In addition, they were clustered with other NAC transcription factor with known function related to growth and development, senescence, fruit ripening, stress response, and secondary cell wall and vascular development. Our results indicate that these six strawberry NAC proteins could play different important regulatory roles in the process of development and ripening of the fruit, providing the basis for further functional studies and the selection for NAC candidates suitable for biotechnological applications.

Strawberry fruit (Fragaria × ananassa) is a soft fruit with high water content at ripe stage (more than 90% of its fresh weight). Aquaporins play an important role in plant water homeostasis, through the facilitation of water transport and solutes. We report the role played by FaNIP1;1 in the receptacle ripening process. The analysis by qRT-PCR of FaNIP1;1 showed that this gene is mainly expressed in fruit receptacle and has a ripening-related expression pattern that was accompanied by an increase in both the abscisic acid and water content of the receptacle throughout fruit ripening. Moreover, FaNIP1;1 was induced in situations of water deficit. Additionally, we show that FaNIP1;1 expression was positively regulated by abscisic acid and negatively regulated by auxins. The water transport capacity of FaNIP1;1 was determined by a stopped-flow spectroscopy in yeast over-expressing FaNIP1;1. Glycerol, H2O2 and boron transport were also demonstrated in yeast. On the other hand, GFP-FaNIP1;1 fusion protein was located in plasma membrane. In conclusion, FaNIP1;1 seems to play an important role increasing the plasma membrane permeability, that allows the water accumulation in the strawberry fruit receptacle throughout the ripening process.

Natural substances such as elicitors of plant defense response, has become a promising option for effective management of plant diseases and are a prerequisite for sustainable and ecological agriculture. Recognition of diverse elicitors, effectors and modulators by specific and nonspecific plant receptors activates signalling cascades eventually leading to gene expression and defense responses. Elicited plants or "primed plants" display either faster, stronger, or both activation of the various cellular defense responses that are induced following attack by either pathogens or insects or in response to abiotic stress. The aim of this work has been to develop new elicitor compounds from natural vegetal substrates, and predict its effectiveness in the field by using robust molecular techniques and appropriate biomarkers of plant defense. Thus, Fragaria x ananassa Duch. cv. Chandler cell suspension cultures, and real-time, quantitative PCR analysis (RTqPCR) were utilized to test the elicitor capability of new natural elicitors. This experimental approach was applied to analyze the pattern of gene expression of specific strawberry genes already known to be good markers of SA- and JA-dependent signalling pathways, which were used as defense induced biomarkers in plants. In addition, determination of total phenols and antioxidant activity, and HPLC-DAD-MS analysis of polyphenolic compounds was performed in these cell suspension samples. Susceptibility to C. acutatum of strawberry plants treated with the new elicitor was performed in greenhouse under controlled conditions. In collaboration with AGROMETODOS, S.A., we have produced new natural compounds that can act as elicitors. We have compared the elicitor activity of a new compound (EH) with the commercial product BROTOMAX ® . The new product EH and BROTOMAX ® activate plant defense related genes in cell suspension cultures. Also, both products induce polyphenol production in this assay. The new product EH and BROTOMAX ® increased the strawberry (Fragaria x ananassa Duch. cv. Camarosa) and olive (Olea europaea L. cv. Picual) resistance against Colletotrichum acutatum and Fusicladium oleaginum plant infections, respectively. We can conclude that new natural bioelicitors can be produced by low-cost procedures based on fermentation of natural substrates derived from plants. The use of suitable, sensitive, appropriate and robust molecular biomarkers also provide an excellent molecular tool to predict the effectiveness in the field of natural compounds with potential eliciting ability, which may be conveniently exploited as ecological bioinducers of plant defense response in strawberry and in many other important crops.

Pectins are essential components of primary plant cell walls and middle lamellae, and are related to the consistency of the fruit and its textural changes during ripening. In fact, strawberries become soft as the middle lamellae of cortical parenchyma cells are extensively degraded during ripening, leading to the observed short post-harvest shelf life. Using a custom-made oligonucleotide-based strawberry microarray platform, a putative rhamnogalacturonate lyase gene (FaRGlyase1) was identified. Bioinformatic analysis of the FaRGlyase1 sequence allowed the identification of a conserved rhamnogalacturonate lyase domain, which was also present in other putative RGlyase sequences deposited in the databases. Expression of FaRGlyase1 occurred mainly in the receptacle, concurrently with ripening, and it was positively regulated by abscisic acid and negatively by auxins. FaRGLyase1 gene expression was transiently silenced by injecting live Agrobacterium cells harbouring RNA interference constructs into fruit receptacles. Light and electron microscopy analyses of these transiently silenced fruits revealed that this gene is involved in the degradation of pectins present in the middle lamella region between parenchymatic cells. In addition, genetic linkage association analyses in a strawberry-segregating population showed that FaRGLyase1 is linked to a quantitative trait loci linkage group related to fruit hardness and firmness. The results showed that FaRGlyase1 could play an important role in the fruit ripening-related softening process that reduces strawberry firmness and post-harvest life., R.B.-P. is grateful for the award of a post-doctoral contract of Campus de Excelencia Internacional Agroalimentario CeiA3 kindly provided by Córdoba University (Spain). C.V. and A.M. thank EUI2008-03770 of Euroinvestigacion Subprogram from PLANT_KBBE Call, provided by the Science and Technology Spanish Minister, and the Centre CONSOLIDER on Agrigenomics and the Xarxa de Referencia en Biotecnología of the Generalitat de Catalunya. This work was supported by the Spanish Ministry of Science and Innovation (MICINN) (BIO2010-19322 and EUI2008-03668).

Understanding the nature of pathogen host interaction may help improve strawberry (Fragaria × ananassa) cultivars. Plant resistance to pathogenic agents usually operates through a complex network of defense mechanisms mediated by a diverse array of signaling molecules. In strawberry, resistance to a variety of pathogens has been reported to be mostly polygenic and quantitatively inherited, making it difficult to associate molecular markers with disease resistance genes. Colletotrichum acutatum spp. is a major strawberry pathogen, and completely resistant cultivars have not been reported. Moreover, strawberry defense network components and mechanisms remain largely unknown and poorly understood. Assessment of the strawberry response to C. acutatum included a global transcript analysis, and acidic hormones SA and JA measurements were analyzed after challenge with the pathogen. Induction of transcripts corresponding to the SA and JA signaling pathways and key genes controlling major steps within these defense pathways was detected. Accordingly, SA and JA accumulated in strawberry after infection. Contrastingly, induction of several important SA, JA, and oxidative stress-responsive defense genes, including FaPR1-1, FaLOX2, FaJAR1, FaPDF1, and FaGST1, was not detected, which suggests that specific branches in these defense pathways (those leading to FaPR1-2, FaPR2-1, FaPR2-2, FaAOS, FaPR5, and FaPR10) were activated. Our results reveal that specific aspects in SA and JA dependent signaling pathways are activated in strawberry upon interaction with C. acutatum. Certain described defense-associated transcripts related to these two known signaling pathways do not increase in abundance following infection. This finding suggests new insight into a specific putative molecular strategy for defense against this pathogen., This work was supported by Junta de Andalucía, Spain [Proyectos de Excelencia P07-AGR-02482/P12-AGR-2174, and grants to Grupo-BIO278].

Strawberry, a small fruit crop of great importance throughout the world, has been considered a model plant system for Rosaceae, and is susceptible to a large variety of phytopathogenic organisms. Most components and mechanisms of the strawberry defense network remain poorly understood. However, from current knowledge, it seems clear that the ability of a strawberry plant to respond efficiently to pathogens relies first on the physiological status of injured tissue (pre-formed mechanisms of defense) and secondly on the general ability to recognize and identify the invaders by surface plant receptors, followed by a broad range of induced mechanisms, which include cell wall reinforcement, production of reactive oxygen species, phytoalexin generation and pathogenesis-related protein accumulation. Dissection of these physiological responses at a molecular level will provide valuable information to improve future breeding strategies for new strawberry varieties and to engineer strawberry plants for durable and broad-spectrum disease resistance. In turn, this will lead to a reduction in use of chemicals and in environmental risks. Advances in the understanding of the molecular interplay between plant (mainly those considered model systems) and various classes of microbial pathogens have been made in the last two decades. However, major progress in the genetics and molecular biology of strawberry is still needed to uncover fully the way in which this elaborate plant innate immune system works. These fundamental insights will provide a conceptual framework for rational human intervention through new strawberry research approaches. In this review, we will provide a comprehensive overview and discuss recent advances in molecular research on strawberry defense mechanisms against pathogens.