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Climate-smart agricultural practices influence the fungal communities and soil properties under major agri-food systems

madhu choudhary ML JAT Parbodh Chander Sharma (2022, [Artículo])

Fungal communities in agricultural soils are assumed to be affected by climate, weather, and anthropogenic activities, and magnitude of their effect depends on the agricultural activities. Therefore, a study was conducted to investigate the impact of the portfolio of management practices on fungal communities and soil physical–chemical properties. The study comprised different climate-smart agriculture (CSA)-based management scenarios (Sc) established on the principles of conservation agriculture (CA), namely, ScI is conventional tillage-based rice–wheat rotation, ScII is partial CA-based rice–wheat–mungbean, ScIII is partial CSA-based rice–wheat–mungbean, ScIV is partial CSA-based maize–wheat–mungbean, and ScV and ScVI are CSA-based scenarios and similar to ScIII and ScIV, respectively, except for fertigation method. All the scenarios were flood irrigated except the ScV and ScVI where water and nitrogen were given through subsurface drip irrigation. Soils of these scenarios were collected from 0 to 15 cm depth and analyzed by Illumina paired-end sequencing of Internal Transcribed Spacer regions (ITS1 and ITS2) for the study of fungal community composition. Analysis of 5 million processed sequences showed a higher Shannon diversity index of 1.47 times and a Simpson index of 1.12 times in maize-based CSA scenarios (ScIV and ScVI) compared with rice-based CSA scenarios (ScIII and ScV). Seven phyla were present in all the scenarios, where Ascomycota was the most abundant phyla and it was followed by Basidiomycota and Zygomycota. Ascomycota was found more abundant in rice-based CSA scenarios as compared to maize-based CSA scenarios. Soil organic carbon and nitrogen were found to be 1.62 and 1.25 times higher in CSA scenarios compared with other scenarios. Bulk density was found highest in farmers' practice (Sc1); however, mean weight diameter and water-stable aggregates were found lowest in ScI. Soil physical, chemical, and biological properties were found better under CSA-based practices, which also increased the wheat grain yield by 12.5% and system yield by 18.8%. These results indicate that bundling/layering of smart agricultural practices over farmers' practices has tremendous effects on soil properties, and hence play an important role in sustaining soil quality/health.

Agriculture Management Fungal Community Diversity Indices Climate-Smart Agricultural Practices CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA AGRICULTURE TILLAGE CLIMATE-SMART AGRICULTURE SOIL ORGANIC CARBON

Estudios de genética en poblaciones de abulón y sus aplicaciones en ordenamiento pesquero

RICARDO PEREZ ENRIQUEZ NOE DIAZ VILORIA JOSE LUIS GUTIERREZ GONZALEZ ALEJANDRA ARCINIEGA DE LOS SANTOS ADRIANA MAX AGUILAR Pedro Cruz Hernández Fernando Aranceta Garza (2016, [Artículo])

"Se presenta la integración de más de 10 años de investigación científica en genética de las poblaciones de abulón en México realizada en el CIBNOR. Esta investigación muestra cómo se pueden aplicar los marcadores genéticos tanto en estudios de genética poblacional como en identificación forense con la finalidad de contribuir al conocimiento aplicado para manejo de la pesquería. Se desarrollaron marcadores genéticos tipo microsatélites de ADN enfocados tanto al abulón azul Haliotis fulgens como amarillo Haliotis corrugata para diferenciación de poblaciones y análisis de parentesco. Un análisis de estructura genética de las poblaciones silvestres de ambas especies de abulón mostró homogeneidad genética en la costa del Pacífico en la región centro-sur de la Península de Baja California, México, pero con diferenciación genética en localidades distantes debido a un flujo genético limitado producto del aislamiento reproductivo. Por ello, no existen elementos que den soporte a un manejo pesquero delimitado por bancos en ambas especies. De manera particular, el abulón amarillo mostró una menor de diversidad genética que el azul, posiblemente debido a una mayor explotación pesquera histórica. Los resultados obtenidos en pruebas de parentesco han indicado que la retención larvaria en bancos específicos es reducida, por lo que ni la agregación de reproductores ni la liberación de larvas han mostrado ser estrategias eficientes para favorecer el incremento de reclutas en bancos definidos. Un análisis de perfiles genéticos con el gen de la lisina permitió la identificación de las especies de abulón que se capturan y enlatan en México. El análisis comparativo de perfi les genéticos, basado en el gen nuclear 18S de abulón y otros moluscos, detectó producto enlatado conteniendo especies de moluscos comercializadas falsamente como abulón, lo que puede constituirse como una herramienta forense en futuras disputas legales. Este tipo de aplicación es potencialmente utilizable con otros productos comestibles en los cuales se sospecha de prácticas fraudulentas, ya sea por captura o comercialización ilegal o por sustitución de contenidos en productos procesados."

"This is an integrative work of more than 10 years of research in population genetics of abalone in Mexico performed at CIBNOR. It shows how molecular tools have the potential to support abalone fisheries management through population genetics and forensic analyses. Microsatellite DNA markers were developed on blue (green for its name in English) Haliotis fulgens and yellow abalone (pink for its name in English) H. corrugata to be used for genetic differentiation on populations and for parentage analysis. The analysis of genetic structure on wild populations of both species revealed genetic homogeneity in the Pacific coast of the central region of the Baja California Peninsula, Mexico, with genetic differentiation on distant localities due to a limited gene flow as a result of reproduction isolation. From this result we suggest that no evidences were found supporting the management of the fishery based on individual abalone beds. Pink abalone shows lower genetic diversity than green abalone, possibly due to higher historical fishery exploitation. The parentage analysis suggested that larval retention within beds is reduced, indicating that neither broodstockaggregation nor the release of abalone larvae for stock enhancement are efficient strategies to increase recruitment in specific beds.

An analysis of the genetic profiles with the lysine gene allowed the identification of abalone species captured and processed in Mexico. The comparative analysis, based on the 18S gene, among abalone and other mollusks, detected canned product containing mollusks that are commercialized allegedly as abalone or ‘abalone type’, which could constitute a forensic tool in future legal disputes. This type of application can also be used with other edible products in which fraudulent practices are suspected either because of illegal catch or commercialization or substitution in processed products."

Análisis forense, diversidad genética, gen 18S, genética de poblaciones, marcadores genéticos, retención larvaria Forensic analysis, genetic diversity, 18S gene, genetic markers, population genetics, larval retention BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA GENÉTICA GENÉTICA DE POBLACIONES GENÉTICA DE POBLACIONES

Relación de adenovirus 36 con la obesidad, expresión de genes (c/ebpB y hif-1A) y la morfologia del tejido adiposo.

JORGE BARRERA ALCOCER (2021, [Tesis de doctorado])

Introducción: Al origen infeccioso de la obesidad se le conoce como ¿infectobesidad¿. Los primeros estudios realizados en modelos animales, como pollos, ratones y primates no humanos, asociaron la presencia de anticuerpos contra HAd36 con el desarrollo de la obesidad y la ganancia de peso, de igual manera los ensayos realizados en preadipocitos (3T3-L1) y células madre adiposas humanas (hASCc) han demostrado que HAd36 se asocia con la expresión de genes implicados en la diferenciación celular y el metabolismo de lípidos. Los estudios realizados para identificar el DNA viral en tejido adiposo son pocos y los resultados inconsistentes. Objetivo: Analizar la presencia del DNA de HAd36 en biopsias de tejido adiposo subcutáneo y su relación con la obesidad, cambios morfológicos de los adipocitos y la expresión de genes adipogénicos y de metabolismo celular. Materiales y Métodos: Se recolectaron un total de 52 biopsias de tejido adiposo subcutáneo de mujeres sometidas a liposucción y/o lipectomia. Se realizó una evaluación antropométrica y clínico-bioquímica. La identificación del DNA de HAd36 se realizó por PCR convencional, la expresión de los genes C/EBPB, HIF-1A y ¿-actina se determinó utilizando sondas TaqMan. La morfología celular se analizó en secciones de tejido adiposo teñidas con H&E, la estimación del número y tamaño de las células se realizó con el software Image J Fiji. Resultados: Se identificó el DNA de HAd36 en 16 muestras de tejido adiposo subcutáneo (31%). La presencia del DNA viral no se asoció con los parámetros antropométricos o metabólicos, tampoco con cambios en la morfología del tejido adiposo. Los niveles de expresión de mRNA para C/EBPB y HIF-1A no mostraron diferencias significativas entre las muestras positivas y negativas al DNA viral (p>0.05). Conclusión: El DNA de HAd36 puede estar presente en el tejido adiposo subcutáneo, pero la presencia del DNA viral no se encontró relacionado con los cambios morfológicos en este tejido, ni con la expresión de genes como C/EBPB y HIF-1A.

BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA GENÉTICA GENÉTICA CLÍNICA

Using an incomplete block design to allocate lines to environments improves sparse genome-based prediction in plant breeding

Osval Antonio Montesinos-Lopez ABELARDO MONTESINOS LOPEZ RICARDO ACOSTA DIAZ Rajeev Varshney Jose Crossa ALISON BENTLEY (2022, [Artículo])

Genomic selection (GS) is a predictive methodology that trains statistical machine-learning models with a reference population that is used to perform genome-enabled predictions of new lines. In plant breeding, it has the potential to increase the speed and reduce the cost of selection. However, to optimize resources, sparse testing methods have been proposed. A common approach is to guarantee a proportion of nonoverlapping and overlapping lines allocated randomly in locations, that is, lines appearing in some locations but not in all. In this study we propose using incomplete block designs (IBD), principally, for the allocation of lines to locations in such a way that not all lines are observed in all locations. We compare this allocation with a random allocation of lines to locations guaranteeing that the lines are allocated to

the same number of locations as under the IBD design. We implemented this benchmarking on several crop data sets under the Bayesian genomic best linear unbiased predictor (GBLUP) model, finding that allocation under the principle of IBD outperformed random allocation by between 1.4% and 26.5% across locations, traits, and data sets in terms of mean square error. Although a wide range of performance improvements were observed, our results provide evidence that using IBD for the allocation of lines to locations can help improve predictive performance compared with random allocation. This has the potential to be applied to large-scale plant breeding programs.

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA Bayes Theorem Genome Inflammatory Bowel Diseases Models, Genetic Plant Breeding

Bacterial communities in the rhizosphere at different growth stages of maize cultivated in soil under conventional and conservation agricultural practices

Yendi Navarro-Noya Bram Govaerts Nele Verhulst Luc Dendooven (2022, [Artículo])

Farmers in Mexico till soil intensively, remove crop residues for fodder and grow maize often in monoculture. Conservation agriculture (CA), including minimal tillage, crop residue retention and crop diversification, is proposed as a more sustainable alternative. In this study, we determined the effect of agricultural practices and the developing maize rhizosphere on soil bacterial communities. Bulk and maize (Zea mays L.) rhizosphere soil under conventional practices (CP) and CA were sampled during the vegetative, flowering and grain filling stage, and 16S rRNA metabarcoding was used to assess bacterial diversity and community structure. The functional diversity was inferred from the bacterial taxa using PICRUSt. Conservation agriculture positively affected taxonomic and functional diversity compared to CP. The agricultural practice was the most important factor in defining the structure of bacterial communities, even more so than rhizosphere and plant growth stage. The rhizosphere enriched fast growing copiotrophic bacteria, such as Rhizobiales, Sphingomonadales, Xanthomonadales, and Burkholderiales, while in the bulk soil of CP other copiotrophs were enriched, e.g., Halomonas and Bacillus. The bacterial community in the maize bulk soil resembled each other more than in the rhizosphere of CA and CP. The bacterial community structure, and taxonomic and functional diversity in the maize rhizosphere changed with maize development and the differences between the bulk soil and the rhizosphere were more accentuated when the plant aged. Although agricultural practices did not alter the effect of the rhizosphere on the soil bacterial communities in the flowering and grain filling stage, they did in the vegetative stage.

Community Assembly Functional Diversity Intensive Agricultural Practices Plant Microbiome CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA SUSTAINABLE AGRICULTURE TILLAGE SOIL BACTERIA MAIZE