ABSTRACT: Based on the data of China’s overseas arable land investment in 47 countries along the “Belt and Road”, the Tobit model is used to analyze the effects of cultural distance and friendship cities on the production rates of contracted arable land in China’s overseas arable land investment. This study provided theoretical basis and empirical support for promoting China’s agricultural “going abroad” and improving the production rates of contracted arable land in China’s overseas arable land investment. The results show that differences in cultural distance, power distance and the degree of uncertainty avoidance have significant positive effects on the production rates of contracted arable land in China’s overseas arable land investment, and differences in individualism have a significant negative effect on the production rates. Friendship city has a positive but insignificant effect on the production rates, meanwhile, it also weaken the positive impact of cultural distance on production rates of contracted arable land in China’s overseas arable land investment. The proportion of joint ventures with host country, the economic level and institutional environment of the host country will all have an impact on the production rates. Finally, recommendations are proposed to promote the production rates of contracted arable land, such as focusing on the positive role of cultural distance, establishing friendship cities, and investing host countries with high potential precisely. ABSTRACT Chinas China s 4 Belt Road, Road , Road” going abroad meanwhile Finally precisely

RESUMO: Com base nos dados do investimento da China em terras aráveis no exterior em 47 países ao longo do “Cinturão e Rota”, o modelo Tobit é utilizado para analisar os efeitos da distância cultural e das cidades amigas nas taxas de produção de terras aráveis contratadas no investimento da China em terras aráveis no exterior. Os resultados mostram que as diferenças na distância cultural, na distância de poder e no grau de prevenção de incertezas têm efeitos positivos significativos sobre as taxas de produção de terras aráveis contratadas no investimento em terras aráveis no exterior da China, e as diferenças no individualismo têm um efeito negativo significativo sobre as taxas de produção. As cidades amigas têm um efeito positivo, mas insignificante, sobre as taxas de produção, enquanto estas podem enfraquecer o impacto positivo da distância cultural sobre as taxas de produção de terras aráveis contratadas no investimento em terras aráveis no exterior da China. A proporção de investimento cooperativo entre a China e o país anfitrião, o nível econômico e o ambiente institucional do país anfitrião terão um impacto sobre as taxas de produção. Por fim, são propostas recomendações para promover as taxas de produção das terras aráveis contratadas, tais como a concentração no papel positivo da distância cultural, a criação de cidades da amizade e o investimento em países de acolhimento com elevado potencial. RESUMO 4 Cinturão Rota, Rota , Rota” insignificante fim potencial

The present study analyzed the chemical composition and phytotoxic activity of Artemisia lancea essential oil (EO). Gas chromatography-mass spectrometry (GC-MS) results showed the presence of 55 compounds, representing 82.36% of the entire EO, with eucalyptol (18.7%) being the most abundant constituent. Phytotoxic bioassay results indicated that the EO (concentration ranging from 0.25-5 mg mL−1) inhibited the growth of Amaranthus retroflexus and Setaria viridis. Root length of A. retroflexus and S. viridis were reduced with the increasing concentration of the EO, especially when the EO was applied at 1-5 mg mL−1. When treated with 1-5 mg mL−1 EO, shoot length of A. retroflexus and S. viridis were also significantly suppressed. The half maximal inhibitory concentration (IC50) values for inhibiting root and shoot growth of A. retroflexus by the EO were 0.284 and 0.246 mg mL−1; for S. viridis, the EO showed IC50 values of 0.44 and 0.262 mg mL−1 for root and shoot inhibition, respectively. The most promising findings were observed when A. lancea EO concentration reached 1 mg mL−1 and higher, which completely inhibited seed germination of A. retroflexus and S. viridis. These findings suggest A. lancea EO has potential as an eco-friendly bioherbicide for agricultural weed control. EO. . (EO) chromatographymass chromatography mass GCMS GC MS (GC-MS 5 compounds 8236 82 36 82.36 18.7% 187 18 7 (18.7% constituent 0.255 0255 0.25 0 25 0.25- mL1 mL A S 15 1- mL− suppressed IC (IC50 0284 284 0.28 0246 246 0.24 IC5 044 44 0.4 0262 262 0.26 inhibition respectively higher ecofriendly eco friendly control (EO 823 8 3 82.3 18.7 (18.7 255 025 0.2 2 (IC5 028 28 024 24 04 4 0. 026 26 82. 18. (18. 02 (IC (18 (1 (

Resumen Antecedentes: Los mapas de bosques perturbados son útiles para identificar afectaciones sobre la biodiversidad y los servicios ecosistémicos. Los métodos que emplean únicamente datos espectrales para detectar las perturbaciones a nivel regional tienen limitaciones. El conocimiento de expertos y el análisis de fragmentación puede mejorar la estimación. Preguntas: ¿Cuál es la distribución de los bosques perturbados en una región de alta biodiversidad? ¿Qué tipos de vegetación y regiones son las más afectadas? Descripción de los datos: imágenes satelitales SPOT 2015, Sentinel-2 de 2019. Se colectó información de la vegetación en 653 sitios. Además, se usaron datos de herbario, censos agrícolas y del Inventario Nacional Forestal. Lugar y fecha del estudio: Estado de Chiapas, durante 2018-2022. Métodos: Se elaboró un mapa híbrido de los tipos de vegetación enfatizando la identificación de bosques secundarios, también se realizó un análisis de fragmentación y se calculó la biomasa leñosa por tipo de bosque. Resultados: El 40 % de la superficie del Estado mantiene una cobertura arbórea; pero solo en el 18 % no se aprecia perturbación; la mayor parte de los bosques no perturbados se encuentran en tres regiones: Selva Lacandona, Sierra Madre y Planicie del Golfo. En general la biomasa de los bosques perturbados es significativamente menor que la de su contraparte madura. Conclusiones: En Chiapas la distribución de los bosques en buen estado de conservación está restringida; casi la mitad de ellos se encuentran fuera de las ANP, por lo que es imperativo promover estrategias adicionales para su manejo y conservación.

Abstract Background: Maps of disturbed forests help to identify impacts on biodiversity and ecosystem services. Methods using only spectral data to detect disturbance at the regional level have limitations, but expert knowledge and fragmentation analysis can improve estimation. Questions: What is the distribution of disturbed forests in a region of high biodiversity, and which vegetation types and regions are most affected? Data description: SPOT 2015, Sentinel-2 satellite imagery from 2019. Vegetation data were collected at 653 sites. In addition, herbarium, agricultural census, and National Forest Inventory data were used. Study site and dates: Chiapas State, during 2018-2022. Methods: We elaborated a hybrid map of vegetation types, emphasizing identifying secondary forests. Also, we carried out a fragmentation analysis and calculated the woody biomass per forest type. Results: 40 % of the State still maintains tree cover, but only 18 % is undisturbed; most undisturbed forests are in three regions: Selva Lacandona, Sierra Madre, and Gulf Plain. Overall, the biomass of disturbed forests is significantly lower than that of their mature counterparts. Conclusions: In Chiapas, the distribution of forests with good conservation status is restricted; almost half of them are outside NPAs, so it is imperative to promote additional strategies for their conservation and management.

Resumen Antecedentes: Los sistemas agrícolas tradicionales en Mesoamérica son adaptaciones ancestrales a los diversos y complejos ambientes. La tezcalera representa uno de ellos. Preguntas: ¿En qué contexto ambiental se desarrolla la tezcalera? ¿Cuáles son las prácticas de manejo que se llevan a cabo en la tezcalera?¿Cómo afectan a la riqueza, composición y abundancia de las arvenses? ¿Cómo influyen en la resiliencia del sistema agrícola, de los bosques tropicales secos y al mantenimiento de los recursos para la subsitencia? Especies de estudio: Arvenses en tezcaleras con diferente manejo. Sitio y años de estudio: Zumpahuacán, Estado de México, 2020-2021 Métodos: Entrevistas sobre prácticas de manejo de la tezcalera. Registro de la riqueza, composición y abundancia de malezas en parcelas con diferente historia de manejo. Resultados: Las tezcaleras se originan de la roza-tumba-quema y siguen diferentes rutas: el tlacolol-milsol-regeneración o potrero, y recientemente, cultivo de Agave. Registramos 161 morfoespecies y 45 familias botánicas; 95 % nativas de la selva baja caducifolia. Veinticinco son endémicas de la región del Balsas y 34 están en alguna categoría de riesgo. La riqueza y abundancia de las arvenses varió entre tezcaleras. La composición florística fue similar; 65 % tuvieron valor tangible o intangible. Conclusiones: La tezcalera es una unidad biocultural y un agroecosistema resiliente. Las prácticas tradicionales favorecen la riqueza y composición de las especies nativas. Los herbicidas y la introducción del cultivo de Agave desplazan a los cultivos tradicionales, poniendo en riesgo la agrobiodiversidad local.

Abstract Background: Traditional agricultural systems in Mesoamerica are adaptations of ancient farmers to the complex and varied environments. Tezcalera represents one of them. Questions: How is the environmental context under which the tezcalera develop? Which management practices are followed in tezcalera? How do these management practices affect weeds' richness, composition, and abundance? How do these management practices contribute to the resilience of the agricultural system, the tropical dry forests, and to the maintenance of subsistence resources? Studied species: Weeds growing in tezcaleras with different management. Study site and dates: Zumpahuacán, Estado de México, 2020-2021. Methods: Twenty-four collaborators were interviewed about the environmental, technological, and cultural aspects of tezcalera. We recorded weeds' richness, composition, and abundance in seven plots with different management histories. Results: Tezcaleras originate from the slash-burn process and follow different paths: tlacolol-milsol-shallow plot, potrero, and recently, Agave crop. We recorded 161 morphospecies from 45 botanical families; 95 % were native to tropical dry forests. Twenty-five species are endemic to the Balsas region, and thirty-four are at risk. Richness and abundance varied between tezcaleras, where tlacolol plots exhibited the highest values. Plant composition was similar; 65 % had intangible or tangible values. Conclusions: Tezcalera is a biocultural unit and a resilient agroecosystem. Traditional practices remain and positively impact the richness and composition of native weeds. The uncontrolled use of herbicides and the introduction of Agave crop are displacing traditional crops and modifying traditional practices, risking local agrobiodiversity.

Abstract Background: Agroforestry systems integrate agricultural, forestry and cultural diversity and have been little studied in coastal regions of Mexico. The SA managed by mixtecs and afro-mexicans are unknown. Questions: Which agroforestry systems are found in Mixtec and Afro-Mexican communities? Which are the forms of management, agricultural and agroforestry practices and useful species in agroforestry systems? Studied species: Various. Study site and dates: Santa María Chicometepec, Cerro de la Esperanza, Collantes, Santa Elena Comaltepec, San Agustín Chayuco, Santiago Tetepec, Oaxaca. October 2021 to October 2022. Methods: Sixty semi-structured interviews were conducted with local specialists in three Mixtec and three Afro-Mexican communities. Questions were asked about traditional agroforestry systems, agricultural, agroforestry and management practices, and useful species. Tours and collections of herbarium specimens were carried out. Each system was described, management and agroforestry practices were categorized; and the number of useful species by category of use and cultural group was recorded. Results: Six agroforestry systems were recorded and described: milpa, pastures, plots, acahuales; piñal and coconut. Agricultural practices in Mixtec communities are carried out with basic tools and inputs and the production is for self-consumption and local sale, while in Afro-Mexican communities they are technical, and their destination is regional sale. The most common agroforestry practices were the boundaries and isolated trees. Conclusions: The cultural groups share agroforestry systems, forms of management, and number of useful species is similar, but they differ in agricultural practices. In the agroforestry systems, edible and timber species (firewood, poles, fences, construction) are mainly conserved.

Resumen Antecedentes: Los sistemas agrosilvícolas (SA) integran diversidad agrícola, forestal y cultural. En regiones costeras de México han sido poco estudiados, particularmente los manejados por mixtecos y afromexicanos de la costa de Oaxaca. Preguntas: ¿Qué SA se encuentran en comunidades mixtecas y afromexicanas?, ¿Cuáles son las especies útiles, formas de manejo, prácticas agrícolas y agroforestales de los SA? Especies de estudio: Diversas. Sitio y años de estudio: Santa María Chicometepec, Cerro de la Esperanza, Collantes, Santa Elena Comaltepec, San Agustín Chayuco, Santiago Tetepec, Oaxaca. Octubre 2021 a octubre 2022. Métodos: Se realizaron 60 entrevistas semiestructuradas a especialistas locales en tres comunidades mixtecas y tres afromexicanas. Se preguntó acerca de especies útiles, sistemas agrosilvícolas, prácticas agrícolas, agroforestales y de manejo. Se realizaron recorridos y colectas de ejemplares de herbario. Se describió cada sistema por sus prácticas agroforestales y de manejo. Se registró el número de especies útiles por categoría de uso y grupo cultural. Resultados: Se documentaron y describieron seis SA: milpa, potreros, solares, acahuales, piñal y cocotal. Las prácticas agrícolas en comunidades mixtecas se realizan con herramientas e insumos básicos y la producción tiene un fin de autoconsumo y venta local, mientras que en comunidades afromexicanas son tecnificadas y su destino es la venta regional. Linderos y árboles aislados fueron las prácticas agroforestales más comunes. Conclusiones: Mixtecos y Afromexicanos comparten SA, formas de manejo y prácticas agroforestales, difieren en las prácticas agrícolas. En los SA se conservan principalmente especies comestibles y maderables. El número de especies útiles es similar en comunidades mixtecas y afromexicanas.

Abstract The purpose of the present study was to define the professional competencies and subjects of the conservation and environmental protection axis of the new educational model of the Veterinary Medicine and Zootechnics career of the Autonomous University of Zacatecas, which establishes that the teacher and the student know the competencies by axes in order to make their educational processes more efficient from a global perspective. To do this, we worked with a core academic core of teachers from the academic unit, who were supported by a bibliographic methodology, synthesis and analysis, as well as the understanding of analyzed documents from the field of veterinary medicine. As a result of the teamwork of 50 teachers and 2 specialists in veterinary education, during workshops and based on the documentary review of research articles in veterinary education, through searching in databases such as Scopus, Web of Sciences , Google Schoolar and Dialnet, the following competencies were defined in the axis of conservation and protection of the environment, where the student must be competent in carrying out adequate management and disposal of hazardous infectious biological waste (RPBI), as well as corrosive, reactive, explosive, toxic, flammable and biological material infectious (CRETIB) generated by medical and agricultural activity to avoid environmental contamination and promote good public health. In addition, it must have the capacity to carry out integrated management of the waste produced as a result of agricultural activity to take advantage of it and avoid environmental contamination, as well as design and apply the methodology for the conservation and use of natural resources. The subjects contained in the curricular plan were defined from these competencies.

Resumo O objetivo do presente estudo foi definir as competências e disciplinas profissionais do eixo conservação e proteção ambiental do novo modelo educacional da carreira de Medicina Veterinária e Zootecnia da Universidade Autônoma de Zacatecas, que estabelece que o educador e o aluno conheçam o competências por eixos, com o objetivo de tornar os seus processos educativos mais eficientes numa perspectiva global. Para o que trabalhamos com um núcleo académico constituído por docentes da Unidade Académica, que se apoiaram numa metodologia bibliográfica, de síntese e análise, bem como na compreensão de documentos analisados da medicina veterinária. Como resultado do trabalho em equipe de 50 professores e 2 especialistas em educação veterinária durante oficinas e com base na revisão documental de artigos de pesquisa em educação veterinária por meio da busca nas bases de dados Scopus, Web of Sciences, Google Schoolar e Dialnet, foram definidas as seguintes competências no eixo de conservação e proteção do meio ambiente onde o aluno deve ter competência na realização de gestão e destinação adequada de resíduos biológicos infecciosos perigosos (RPBI), bem como de resíduos biológicos corrosivos, reativos, explosivos, tóxicos, inflamáveis e infecciosos (CRETIB) gerados pela atividade médica e agrícola para evitar a contaminação ambiental e promover a boa saúde pública. Da mesma forma, deve ter capacidade para realizar a gestão integrada dos resíduos produzidos pela actividade agrícola para aproveitá-los e evitar a contaminação ambiental, bem como conceber e aplicar a metodologia de conservação e aproveitamento dos recursos naturais. recursos. As disciplinas constantes do plano curricular são definidas a partir destas competências.

Resumen El propósito del presente estudio fue definir las competencias profesionales y las materias del eje de conservación y protección al medio ambiente del nuevo modelo educativo de la carrera de Medicina Veterinaria y Zootecnia de la Universidad Autónoma de Zacatecas, la cual establece que el docente y el educando conozcan las competencias por ejes con la finalidad de hacer mas eficientes sus procesos educativos desde una óptica global. Para ello, se trabajó con un núcleo académico base de docentes de la unidad académica, los cuales se apoyaron en una metodología bibliográfica, síntesis y análisis, así como en la comprensión de documentos analizados del ámbito de la medicina veterinaria. Como resultado del trabajo en equipo de 50 docentes y 2 especialistas en educación veterinaria, durante talleres de trabajo y con base en la revisión documental de artículos de investigación en educación veterinaria, a través de la búsqueda en bases de datos como Scopus, Web of Sciences, Google Schoolar y Dialnet, se definieron las siguientes competencias en el eje de conservación y protección al ambiente, donde el estudiante debe de ser competente en la realización de un manejo y disposición adecuada de los residuos peligrosos biológico infecciosos (RPBI), así como de material corrosivo, reactivo, explosivo, tóxico, inflamable y biológico infeccioso (CRETIB) generados por la actividad médica y agropecuaria para evitar la contaminación del ambiente y propiciar una buena salud pública. Además, debe tener la capacidad de realizar un manejo integrado de los residuos producidos como resultado por la actividad agropecuaria para aprovecharlos y evitar la contaminación del ambiente, así como diseñar y aplicar la metodología para la conservación y aprovechamiento de los recursos naturales. De estas competencias se definieron las asignaturas contenidas en el plan curricular.

Abstract The National Institute of Biodiversity of Costa Rica (INBio), the first institution of its kind worldwide, was created in 1989 as a civil society organization, with the mission of promoting greater awareness of the value of biodiversity, to achieve its conservation and promote human development. It operated within the framework of a national biodiversity conservation strategy consisting of three types of actions: “save, know and use”, forming a publicprivate alliance with the National System of Conservation Areas, whose work represented the first step of “saving”. INBio focused on the generation of scientific knowledge of Costa Rican biodiversity (knowing) and the search and promotion of its intelligent use (using). This article describes the genesis of the institution and its main contributions to the knowledge and use of Costa Rican biodiversity between 1989-2015. These include the results of the protected areas biodiversity inventory process and the development of the largest systematic collection of biological specimens in the country’s history, fully systematized; the development of an information management system that integrated all the information from the inventory and the specimens in its collection in digital format, allowing global access to this information or its correlation with that of other sources. The results of promoting and facilitating the use of information through five programs: Natural Sciences and Conservation Biology, for scientific purposes; Bioliteracy and Education, conceptually designed for the teaching and development of awareness about the value of biodiversity; Bioprospecting, the systematic search for economic uses of biodiversity for medicinal, agricultural and industrial purposes; Conservation for Development, the use of the information for wild areas conservation purposes, surrounding communities or nature tourism, among others; Technical Assistance and Training, program in charge of assisting public and private entities, inside and outside the country, in the development of initiatives in which Biodiversity was the central element. The main results of its work and the national and international awards that INBio received for its innovative approaches and contributions are described, as well as the financial and political reasons why INBio discontinued its activities in the period 2015-2016 are summarized. Viewing the work of INBio as a first stage, the importance and need to continue with a state program on the knowledge and use of Costa Rican biodiversity is raised, in addition to its protection, with the goal of creating awareness of its value before the serious threats to life on Earth.

Resumen El Instituto Nacional de Biodiversidad de Costa Rica (INBio), la primera institución en su género en el mundo, fue creado en 1989 como una organización de la sociedad civil, con la misión expresa de promover una mayor conciencia del valor de la biodiversidad, para lograr su conservación y fomentar el desarrollo humano. En el marco de una estrategia nacional de conservación de la biodiversidad consistente en tres tipos de acciones: “salvar, conocer y utilizar”, se conformó una alianza público-privada con el Sistema Nacional de Áreas de Conservación, cuya labor representó el primer paso de “salvar”. El INBio se centró en la generación de conocimiento científico de la biodiversidad costarricense (el “conocer”) y en la búsqueda y promoción de su uso inteligente (el “usar”). Este artículo describe la génesis de la institución y sus principales aportes al conocimiento y la utilización de la biodiversidad costarricense en el período 1989-2015. Estos incluyen los resultados del proceso de inventario de la biodiversidad de las áreas protegidas y el desarrollo de la colección sistemática de especímenes biológicos más grande en la historia del país, totalmente sistematizada; el desarrollo de un sistema de manejo de información que integró en formato digital toda la información del inventario y de los especímenes de su colección, permitiendo el acceso global a estos datos o su correlación con la de otras fuentes. Los resultados de la promoción y la facilitación del uso de la información se lograron mediante cinco programas: Ciencias Naturales y Biología de la Conservación, con fines científicos; Bioalfabetización y Educación, conceptualmente diseñados para la enseñanza y el desarrollo de la conciencia del valor de la biodiversidad; Bioprospección, la búsqueda sistemática de usos económicos de la biodiversidad para fines medicinales, agrícolas e industriales; Conservación para el Desarrollo, el empleo de la información para la conservación de áreas silvestres, comunidades circunvecinas o turismo naturalista, entre otros; y Asistencia Técnica y Capacitación, programa encargado de asistir a entidades públicas y privadas, dentro y fuera del país, en el desarrollo de iniciativas en que la biodiversidad fuera el elemento central. Se describen los principales resultados de su labor y los reconocimientos nacionales e internacionales que el INBio recibió por sus novedosos enfoques y aportes, al igual que se resumen las razones de carácter financiero y político por las cuales el INBio descontinuó sus actividades en el período 2015-2016. Vista la labor del INBio como una primera etapa, se plantea la importancia y necesidad de continuar con un programa estatal sobre el conocimiento y uso de la biodiversidad costarricense, en adición a su protección, con el fin último de que exista conciencia de su valor ante las serias amenazas para la vida en el planeta.

Abstract: In vitro propagation protocols for Theobroma cacao have focused on the multiplication of genotypes with the use of 2,4-diclorofenoxiacetic acid (2,4-D) and thidiazuron (TDZ) in the initial phase of the process. There are no reports of the use of indole-3-acetic acid (AIA) as a source of auxin. Due to risks for human health and the environment, international bans have been placed on the use of 2,4-D. The objective of this study was to evaluate the capacity of AIA in combination with TDZ as inducers of embryogenic usfrom staminodes and petals of the Creole and Trinitarian genotypes of T. cacao. The results showed that the combination of AIA 1.0 mg L-1 and TDZ0.005 mg L-1 induced callus in 100 % of explants; the rest of the combinations of AIA and TDZ induced callus in 50 % and 80 % of explants. In conclusion, the use of AIA is useful for the formation of friable callus in in vitro cultures of T. cacao.

Resumen: El nitrógeno en el suelo es crucial para la agricultura, pero a menudo es limitante, afectando el rendimiento de los cultivos. La deficiencia requiere fertilizantes sintéticos, pero su uso inadecuado causa daños ambientales y costos elevados. Las bacterias del género Rhizobium, simbiontes de leguminosas, ofrecen una solución al fijar nitrógeno de manera sostenible, reduciendo la dependencia de fertilizantes. Esta investigación determinó el número más probable (NMP) de células de Rhizobium spp. procedente de dos biofertilizantes comerciales de origen ecuatoriano y mexicano en condiciones de invernadero. Para esto, se realizó la inoculación directa con disoluciones seriadas (10-1 a 10-10) en macetas con pomina esterilizada al vapor, donde se germinaron plantas de frijol ejotero (Phaseolus vulgaris L.) de la variedad Blue Lake. A los 45 días después de siembra (DDS) se evaluaron los siguientes indicadores morfológicos: área foliar, peso de la planta en húmedo, altura de planta y número de flores, determinándose diferencias estadísticas entre el tipo de biofertilizante y la concentración de cada dilución. El experimento se adecuó a un diseño de bloques completos al azar con arreglo de parcela dividida con tres repeticiones por dilución, en consideración de las fluctuaciones de temperatura presentes en la zona de estudio. El NMP, al 95% de confianza, fue de 4,45x107 rizobios g-1 de pomina en una dilución 10-5 para el biofertilizante mexicano, y 1,48x105 rizobios g-1 de pomina en una dilución 10-4 para el biofertilizante ecuatoriano. La dilución óptima estimada para ambos productos fue de 10-8.

Abstract: Soil nitrogen is crucial for agriculture, but it is often limited, affecting crop yields. Deficiency requires synthetic fertilizers, but their improper use results in environmental damage and high costs. Bacteria of the genus Rhizobium, symbionts of legumes, offer a sustainable solution by fixing nitrogen, thus reducing dependence on fertilizers. This research determined the most probable number (MPN) of cells of Rhizobium spp. from two commercial biofertilizers of Ecuadorian and Mexican origin under greenhouse conditions. For this, direct inoculation with serial dilutions (10-1 to 10-10) was performed in pots with steam-sterilized pumice where Blue Lake variety snap bean (Phaseolus vulgaris L.) plants were germinated. The following morphological indicators were evaluated at 45 days after sowing (DAS): leaf area, plant wet weight, plant height, and number of flowers, determining statistical differences between the type of biofertilizer and the concentration of each dilution. The experiment followed a randomized complete block design with a split-plot arrangement, with three replicates per dilution, considering temperature fluctuations in the study area. The MPN at 95% confidence was 4.45x107 rhizobia g-1 of pumice at a 10-5 dilution for the Mexican biofertilizer, and 1.48x105 rhizobia g-1 of pumice at a 10-4 dilution for the Ecuadorian biofertilizer. The estimated optimal dilution for both products was 10-8.

Resumen La frutilla chilena (Fragaria chiloensis) es una especie nativa de Chile. Es un fruto apreciado por los consumidores por sus propiedades organolépticas, pero es altamente perecedero. Dado que es un fruto no climatérico, debe ser cosechado en el momento óptimo de maduración para asegurar su calidad durante la comercialización. La calidad de estos frutos se mide por apariencia, sabor, aroma, valor nutricional y firmeza, la cual experimenta cambios durante el proceso de maduración. La especie presenta una alta tasa de pérdida de firmeza o ablandamiento, que se asocia a la elevada actividad de enzimas de las fracciones hemicelulosa y pectina de la pared celular, como la poligalacturonasa, a-arabinofuranosidasa, p-galactosidasa, endo-glucanasa, p-xilosidasa, xiloglucano endotransglicosilasa/hidrolasa y ramnogalacturonano liasa en diversas etapas de maduración. La firmeza es un atributo clave para la comercialización y la mantención de la calidad organoléptica, por lo que su control es necesario durante el almacenamiento. Para ello, se han investigado los efectos de tratamientos pre o postcosecha, como atmósferas modificadas, y aplicaciones exógenas de calcio, auxina, metil jasmonato, quitosano y sulfuro de hidrógeno, que contribuyen a mantener este atributo al reducir la solubilización de las pectinas, así como otros aspectos de la calidad organoléptica y nutricional durante el almacenamiento. Esta revisión bibliográfica presenta hallazgos sobre la biología de maduración de Fragaria chiloensis, las investigaciones más recientes sobre el fenómeno de ablandamiento y sus bases bioquímicas y moleculares, así como intervenciones orientadas a mantener la calidad y extender la vida postcosecha de este fruto.

Abstract The Chilean strawberry (Fragaria chiloensis) is a native species to Chile. Consumers value this fruit for its organoleptic properties, but it is highly perishable. Since it is a non-climacteric fruit, harvesting at the optimum ripening stage is essential to ensure its quality during commercialization. In this fruit, quality is determined by appearance, flavor, aroma, nutritional value, and firmness, which changes during ripening. The species presents a high rate of firmness loss or softening, associated with the elevated enzymatic activity of cell wall-modifying enzymes of the pectin and hemicellulose fractions, such as polygalacturonase, a-arabinofuranosidase, p-galactosidase, endo- glucanase, p-xylosidase, xyloglucan endotransglycosilase/hydrolase and rhamnogalacturonan lyase at different ripening stages. Firmness is a key trait for commercialization and organoleptic quality; hence, its management during storage is necessary. Different studies have investigated the effects of pre or postharvest treatments, such as modified atmosphere packaging and exogenous applications of calcium, auxin, methyl jasmonate, chitosan, and hydrogen sulfide, which maintain fruit firmness by reducing pectin solubilization and improve other attributes responsible for organoleptic and nutritional quality during storage. This literature review focuses on the ripening biology of Fragaria chiloensis and recent findings regarding softening and its biochemical and molecular basis, as well as interventions oriented to maintain the quality and extend the shelf-life of this fruit.

Abstract: The expected population growth will increase global food consumption, particularly meat consumption, which is estimated to increase 14% by 2030. Hence, the efficient utilization of all the resources involved in meat production, predominantly feed additives in livestock, is important due to economic costs and the high environmental in terms of gas production and ammonia excretion. Efforts have been made to increase efficiency in livestock production and improve the absorption and utilization of nutrients. Nevertheless, advances in technology in the chemical, pharmaceutical, and food industries have barely been used by the livestock and poultry industry. The micro/nano encapsulation process has been used in animal nutrition to protect bioactive compounds or to control the release of feed additives into the animal gastrointestinal tract, avoiding rumen microbes attack, or monogastric digestion in swine and poultry, to be available in the small intestine. However, not all the encapsulation techniques are suitable for applications in animal feeding. For example, spray drying, emulsion and coacervation can be used to control the release of feed additives in ruminants. In this sense, micro encapsulation of different feed additives such as amino acids, fatty acids, and probiotics may face enormous challenges to help improve livestock and poultry nutrition. The objective of this review is to highlight and discuss the techniques, compounds, and key aspects involved in the encapsulation of feed additives and nutrients with potential applications in the livestock and poultry production.

Abstract: Solid and liquid formulations based on the plant growth-promoting bacteria Bacillus subtilis Bs006 were designed as biological inoculant for vegetable nursery production. Considering the importance of microbial survival from the production process to the soil application, spore viability (CFU) in each formulation was assessed during twelve months of storage at 20, 30, and 40°C. At the three temperature levels evaluated, survival was higher than 85 and 90% for solid and liquid formulations, respectively. The bacterial biological activity was evaluated as plant growth promotion on lettuce, broccoli, and tomato in nursery. The formulations were applied at three concentrations (1x107, 5x107, 1x108 CFU/mL) at sowing and 21 days after seeding. Root and aerial part length and dry weight were the response variables evaluated. A positive effect was observed, particularly with the liquid formulation at 1x108 spores/mL, showing the longest length of root and aerial part and the highest dry weight values in the root and foliar parts. Regarding the endophytism, B. subtilis colonized roots, stems, and leaves, achieving concentrations between 8x102 and 1x105 CFU/g.

Resumen: A pesar de todo el conocimiento generado en torno a las técnicas de injerto en especies vegetales, existe poca investigación que evalúe los resultados encontrados. El objetivo de este trabajo fue analizar, mediante técnicas bibliométricas, la información publicada en artículos científicos donde se evalúo alguna técnica de injerto, para identificar metodologías de análisis, tipos de injertos, especies vegetales y la aplicación de los resultados encontrados. La palabra clave utilizada para la búsqueda de los artículos científicos fue ‘grafting’, y se consideraron publicaciones hasta diciembre de 2022. De 1994 a 2022 se identificaron 293 artículos científicos, la frecuencia de su publicación mostró una tendencia exponencial (R2 = 0,54). Se encontró que se evalúan variables asociadas al portainjerto, injerto y sobrevivencia de la nueva planta formada, que son evaluadas cada vez con mayor frecuencia con técnicas multivariadas por el interés de detectar las variables más significativas a partir de un número elevado de variables analizadas. Se documentaron 11 técnicas de injerto: púa, hendidura, empalme, inglés, yema, in vitro, microinjerto, en T, chapado, chip y entube. Las especies de mayor análisis correspondieron a frutícolas (cítricos), hortícolas (tomate), forestal (nogal), y ornato (rosa). Sin embargo, el 63,47% de los artículos científicos se limitaron a hacer análisis descriptivos sobre prendimiento, compatibilidad y sobrevivencia de los materiales vegetativos. Lo anterior, deja un área de oportunidad para desarrollar investigación sobre los procesos de mejora genética en la búsqueda de caracteres agronómicos de interés (fruto y crecimiento), o bien en la diversidad genética orientada a la productividad y/o conservación.

Abstract: Despite all the knowledge generated about grafting techniques in plant species, there is little research that evaluates the results found. The objective of this work was to analyze, through bibliometric techniques, the information published in scientific articles in which a grafting technique was evaluated, to identify analysis methodologies, types of grafts, plant species, and the application of the results found. The keyword used for the search of scientific articles was ‘grafting’, and publications up to December 2022 were considered. From 1994 to 2022, 293 scientific articles were identified, the frequency of their publication showed an exponential trend (R2 = 0,54). It was found that variables associated with rootstock, graft and survival of the newly formed plant are evaluated, with an increasing use of multivariate techniques in order to detect the most significant variables. Eleven grafting techniques were documented: bark grafting, cleft grafting, splice grafting, whip and tongue grafting, budding, in vitro grafting, micrografting, T-budding, side-veneer grafting, chip budding, and tube grafting. Fruit (citrus), horticultural (tomato), forest (walnut), and ornamental (rose) crops were the most widely analyzed. However, 63,47% of the scientific articles were limited to descriptive analyses on success rate, compatibility and survival rate of vegetative materials. This provides the opportunity to conduct research on genetic improvement processes in the search for agronomic traits of interest (fruit and growth), or on genetic diversity aimed to improve productivity and/or conservation.

Resumen: El objetivo fue evaluar el efecto de algunos factores en características de la canal y las correlaciones fenotípicas entre ellas. Se utilizó la información de registro de 514 bovinos Simmental y 178 Simbrah nacidos entre 2011 y 2018 en México. Las características evaluadas fueron área del ojo del lomo (AOL), grasa de la cadera (GC), grasa dorsal (GD), grasa intramuscular ajustada (GI), marmoleo (M) y grado de rendimiento en canal (R). Las medias ajustadas y las correlaciones fenotípicas entre características se estimaron con PROC MIXED y PROC CORR de SAS®. Los efectos fijos incluidos en los modelos fueron: raza, sexo del animal, hato, año de medición, época de medición y edad en días a la medición como covariable lineal; se incluyó al semental anidado en raza como efecto aleatorio. El efecto de raza fue significativo para GC (p<0,001), R (p<0,07) y GD (p<0,07). Los efectos de sexo y época fueron significativos (p<0,001) para todas las características evaluadas. Las correlaciones de AOL con las otras características estudiadas fueron significativas (p<0,001); negativas con GI y M; y positivas con GC, GD y R. Las correlaciones de GC con GD y R fueron importantes y positivas (p<0,001). La selección de fenotipos para aumentar la carne magra puede conducir a una disminución del contenido de grasa. Las correlaciones fenotípicas positivas entre R y los rasgos de calidad de la canal implicarían que los rasgos mencionados pueden mejorarse sin ningún efecto adverso en éstos y R en la población.

Abstract: The objective of this study was to evaluate the effect of some factors on carcass traits and the phenotypic correlations between them. Records from 514 Simmental and 178 Simbrah bovine individuals born in Mexico between 2011 and 2018 were used. The variables evaluated were rib eye area (AOL), rump fat thickness (GC), back fat thickness (GD), adjusted intramuscular fat (GI), marbling (M) and carcass yield grade (R). Adjusted means and phenotypic correlations between traits were estimated with PROC MIXED and PROC CORR of SAS®. The fixed effects included in the models were breed, sex of the animal, herd, year of measurement, season of measurement, and age in days at measurement as a covariate; sire nested in breed was included as a random effect. The effect of breed was significan for GC (p<0.001), R (p<0.07) and GD (p<0.07). The effects of sex and season were significant (p<0.001) for all the evaluated traits. The correlations of AOL with all other traits were significant (p<0.001); negative with GI and M; and positive with GC, GD, and R. The correlations of GC with GD and R were important and positive (p<0.001). Selecting phenotypes to increase lean meat can lead to a decreased fat content. The positive phenotypic correlations between R and carcass quality traits would imply that the aforementioned traits can be improved without any adverse effects on them and R in the population.

Abstract: This study determined the in vitro effects of ethyl nitroacetate (ENA), ethyl 2-nitropropionate (E-2-NPP) and 3-nitropropionic acid (NPA) on ruminal production of CH4, H2, volatile fatty acids (VFAs) and in vitro dry matter disappearance of ground alfalfa. In vitro incubations were carried out over 24-h succeeding days (3 batches). Total gas and methane production decreased with all nitro compounds (P < 0.05) in all the batches. Total production of VFAs was reduced by ENA and E-2- NPP (P < 0.05), but not by NPA. DM disappearance was similar between treatments but decreased across batches. Further studies should be aimed at understanding the impact of NPA on ruminal metabolism, as well as its effect on in vivo models.