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Objective: To evaluate the diversity and abundance of rodent species, as well as vegetation cover, under three habitat conditions in the Altiplano Potosino Oeste. Design/Methodology/Approach: The work was carried out in eight sites with good (3), regular (2), and poor (3) vegetation cover conditions. Frequency, basal, and aerial cover data were collected in three plot sizes to obtain the results for the three types of vegetation: arborescent stratum (20×20 m), shrubs (3 plots of 5×5 m), and herbaceous stratum (2 plots of 1×1m). In order to collect the rodent data, three sampling nets with 100 Sherman traps were used. Rodent species diversity was determined using the Shannon-Whinner index (SWI), while abundance was obtained using the Relative Density Index (RDI). Differences were determined using ANOVA. Results: Grass cover decreased depending on the condition; however, this was not the case of the shrub cover. The overall diversity of rodent species was 21 (16 in fair, 15 in good, and 14 in poor condition). The total SWI and RDI decreased depending on the condition. Dipodomys ornatus, D. merriami, and Chaetodipus nelsoni were the most abundant and most widespread species. Study Limitations/Implications: The study was conducted during the most restrictive season and under drought conditions. This situation impacted cattle, but not rodents. However, although their plasticity maintained relatively stable RDI values, the indices decreased depending on the condition. Findings/Conclusions: Despite their habitat conditions, the rodents found in the area are more diverse and abundant than those reported in reference works. Therefore, further studies about this subject should be carried out using rodents as bioindicators

Objective. To characterize the habitat of the Montezuma quail (Cyrtonyx montezumae) in Rancho Chapultepec, Durango, Mexico.Design/Methodology/Approach. From February to October 2020, fieldwork was carried out to search for Montezuma quail sites using transects and sounds. Subsequently each site-of-use was characterized; for each of them three random sites were located. Intercept lines (or Canfield), embedded frames, and nearest neighbour techniques were used. Recorded data were analysed using Principal component analysis (PCA); Frequency ofobservation (FO); Kruskal-Wallis; and Poisson regression (PR).Results. The PCA showed values for sites of use= 48, non-use= 43, and both= 36 of the present variability in vegetation-habitat variables. FO showed values per site of use = 6.25%; non-use = 2.08% and both = 1.56%; and per species in sites of use = 3.57, non- use = 3.85 and both = 3.33%. Kruskal-Wallis exhibited significant differences in richness and abundance and similarity in diversity. Poisson regression (PR) showed the effect of some vegetation-habitat variables on the Montezuma quail.Limitations /Implications of the study. The monitoring period evaluated only comprised a short space of time. It is suggested to extend the sampling time, allowing to visualize the population fluctuation regarding this variable.Findings/Conclusions: It was possible to determine that there is an association between the variables of the vegetation-habitat with the presence of C. montezumae. Vegetation type is the variable that determines the incidence of this species.

Objective: To characterize the goat producers according to the industrial destinations of the milk, in order to analyze the coordination mechanisms established in the agri-food chain. Design/Methodology/Approach: A survey was applied to 122 randomly selected goat producers. Taking into account two industrial destinations, a socioeconomic, productive, and commercial comparison was carried out, through T-tests for independent means. In order to analyze the coordination mechanisms, the data were complemented interviewing owners of collection centers and businessmen who processed milk. Results: The producers had small herds and a basic level of education. They used family workforce. The lack of organization in the sale limited their participation in the agri-food chain coordination. Milk processing companies coordinate their efforts, organizing the collection, reaching trade agreements, setting prices, and establishing quality rules, usually through informal agreements. Limitations/Implications: State intervention is necessary to regulate relations between the actors of the agri-food chain. Findings/Conclusions: The informality of coordination mechanisms favors agribusiness and turns them into forms of domination that ensure their profitability

Objective: The objective of this study was to establish the method of propagation of Oryganum vulgare and Lippia graveolens employing a plant tissue culture technique that decreased the phenolization percentages and increased the multiplication coefficients. Design/ methodology/ approach: The in vitro germination percentage was evaluated in both MS and MS medium + activated carbon. Microcuttings (small shoots) of both species were established in base medium added with different antioxidant agents to decrease the phenolization of explants; the treatments were arranged in a completely randomized block design. For the propagation phase, a completely randomized factorial design was used, where the auxin/cytokinin phytoregulators, type of explants (axillary buds and leaves), and the species (Lippia graveolens and Oryganum vulgare) were considered as factors. Results: maximum germination (63.3% ±12.5) was obtained on day 15 ​​in both culture media for L. graveolens and O. vulgare. The use of antioxidant agents mainly activated carbon, increased the in vitro establishment and activation of vegetative buds in both species by up to 90%. There were significant differences in the variables evaluated regarding the treatments, the explant, and the species in the multiplication phase. The combination 1.0/ 0.5 mg L-1 BA/AIB induces callus formation for both species. When used as leaf explants, callus formation was potentiated. Study Limitations / Implications: The results presented are advances from a long-term experiment. Findings/conclusions: The germination of L. graveolens seeds can be achieved in MS medium after 15 days. Microcuttings of both L. graveolens and O. vulgare were successfully established in MS basal medium enriched with 1 g L-1 charcoal that showed low oxidation percentages and induced up to 90% the production of shoots in the explants. The mixture of 1.0/0.5 mg L-1 BA/AIB induces callus formation for both species; when this medium is in contact with leaves as an explant, its formation is potentiated, achieving diameters up to 15 mm. In order to achieve the induction of shoots and roots, buds should be established in MS medium enriched with 0.5 mg L-1 IBA for both species; this mixture encreased the multiplication coefficients

Objective: To identify the profile of the companies participating in the Mexican National Exportation Award (NEA) in the Large Agricultural Exporting Companies category (LAEC), by an information-gathering tool to determine the commercial lines of those businesses, their state of origin, and the exports destination. Methodology: a total of 17 questionnaires (n = 17), applied by the NEA to the LAEC category participants during the 2010-2018 period, were analyzed to determine the commercial business lines, their state of origin, and the destination of the exports. A problem tree was created to find opportunity areas to design solution proposals. The collected information was processed in the NetDraw 2.097 software to show the networks, their dominant actors (countries to which they export), and the products that the companies exported the most. Results: pork and vegetables business lines were identified. The latter revealed a sub-network of tomatoes and strawberries. A network was generated with an open structure comprising 17 nodes and 46 links where three export destination countries stood out: the USA with 15 links, Canada with six, and Japan with five. The highest exported product was the tomato in its different varieties, mainly to the U.S. and Canada. Limitations: Scarce information about the award on the internet. Access restrictions. Most of the exporting companies did not respond to the survey. Conclusions: the perishability of exported products determines the number of destination countries. The precariousness of Mexican agricultural exports was identified because companies trade only one product or a reduced number of them to only one country.

Objective: To determine the diet of the desert bighorn sheep and to identify differencesin its composition between sexes during the reproductive and sexual segregation periods.Design/methodology/approach: The study was carried in the UMA Rancho NocheBuena, Hermosillo, Sonora. The microhistological technique and a cell catalog of plantsfrom the study area were used to identify plant species present in fecal samples ofbighorn sheep. The relative frequency, the Shannon-Weaver diversity index and theKulczynski similarity index were determined by sex and period (reproductive andsegregation)Results: The diet of bighorn sheep included 40 species, being herbaceous (36.1 ±4.4%) and grasses (26.8 ±8.9 %) the most common. The diet of males during thesegregation period was mainly composed of grasses (36.2%) and female diet byherbaceous (30%) and grasses (29.8%). No differences were found in the diversity ofthe diet of males and females in the segregation period (H '= 1.0) and in general, their diets were very similar (80%).Limitations/implications: To collect a greater number of fecal samples by sex andperiod (reproductive and segregation) and to analyze the nutritional content of plantsconsumed by bighorn sheep.Findings/conclusions: In this study, the sexual segregation exhibited by the bighornsheep in the Wildlife Management and Conservation Unit Rancho Noche Buena was notdue to food preferences.

Objective: The objective was to infer the effect of the variables phenology (migration-non-migration), seasonal (rainfall-dry season), sex and forest condition on the abundances of birds (resident-migratory) in a semi-preserved and disturbed oak pine forest. Design/methodology/approach: It was carried out in Monte Tlaloc, State of Mexico, under two conditions of apparent disturbance, semi-preserved oak pine forest and disturbed oak pine forest. Ten bird samplings were carried out with "count on point" with a fixed radius of 25 m, covering the 4 seasons of the year and migratory periods. With the previous data, the Relative Abundance Index (RAI) was estimated. To infer the effect of the variables phenology, seasonality, sex and forest condition on the abundances of birds, generalized linear models were elaborated. Results: The IAR of the birds registered in the semi-considered pine forest indicates that the species with the lowest presence was Aphelocoma ultramarina (0.002) and with the highest frequency Empidonax sp. (0.13), unlike to that found in the disturbed pine forest where the lowest IAR corresponded to Colaptes auratus (0.003) and with the highest appearance was Ptiliogonys cinereus (0.23). The Generalized Linear Model suggested that forest condition and phenology are significantly related to the frequency of species. Limitations on study/implications: In this study it was found that the abundance of birds was affected by the condition of the forest and that the phenology (migration-non-migration), seasonal (rain-dry season), sex and condition of the forest were related to the abundance of birds. Four species classified as under Special Protection and two Threatened according to NOM-059 were registered as well as the presence of four endemic species which highlights the importance of conserving these ecosystems. Findings/conclusions: The fauna communities present in Monte Tláloc highlight the importance of conserving the pine-oak forests since this site is part of the Eje Neovolcanico Transversal.

Objective: To develop three models in order to estimate the defecation rate ofwhite-tailed deer (Odocoileus virginianus) according to the season of the year,content of neutral detergent fiber (NDF), and acid detergent fiber (ADF) in feces.Design / methodology / approach: Nine captive adult deer were assigned tothree levels of dietary fiber. Fecal groups (defecation rate) were counted, forageconsumption was estimated, and feces were analyzed for NDF and ADF content. Arandomized block design was used, where the effect of the treatments was blockedby season, and a multiple regression analysis was used to define the predictionmodels of the defecation rates.Results: The rates were different for dietary fiber levels (p

Objective: To characterize the realized niche of the Mexican spotted owl (Strix occidentalis lucida) and compare the environmental values it uses within the Mexican physiographic provinces.Design/methodology/approach: The environmental temperature variables (n =7), precipitation (n = 7) and elevation (n = 1) were extracted from 79 unique occurrences sites of S. o. lucida. These values were grouped by physiographic provinces: Sierra Madre Occidental (n = 59), Sierra Madre Oriental (n = 13) and Transversal Neovolcanic Belt (n = 6). The climate and elevation of these sites were described and compared via non-parametric Kruskal-Wallis and Bonferroni-Dunn tests (P ? 0.05).Results: The presences of the spotted owls were both, dispersed and focallydistributed, over the geographic space in Mexico. The temperature and elevation variables have similar characteristics in the assessed physiographic provinces. To be noted, the precipitation variables showed significant differences among sites.Limitations on study/implications: This study describes the environmental characteristics of the realized niche of the Mexican spotted owl; however, it isnecessary to investigate other habitat variables at a smaller scale. Findings/conclusions: The temperature and elevation environmentalcharacteristics of the ecological niche of the Mexican spotted owl was similar between physiographic provinces.

Objective: To estimate the waste of fruits, legumes and herbs in the Xalapa wholesale market Central de Abasto Xalapa (CAX). Design/methodology/approach: The tenants and transporters of the wholesale market were interviewed, who estimated the reported information. Results: It was calculated a daily waste 1.7 t (0.7 %) of fruits, legumes and aromatic herbs commercialized in CAX. Tenants unknown the factors that cause this waste. Limitations on study/implications: Few reports are available on the waste of fruits, vegetables and herbs in the wholesale markets in the country. Little awareness exists about this problem in the country. Findings/conclusions: The amount of waste produced daily in CAX indicates the need to review the public policies applicable to improve their coordination and market problems

Objetivo: Evaluar el método de acondicionamiento y desinfección de Sagittaria macrophylla zucc. (Alismataceae) de la Cienega de Lerma, para su propagación y conservación. Diseño/ metodología/ aproximación: En el invernadero se estableció un diseño completamente al azar con tres repeticiones para evaluar dos tipos de sustrato para S. macrophylla, se evaluó el número y longitud de brotes sanos. El primer sustrato consistió en una mezcla de tierra negra y agrolita con una proporción de 2:1, respectivamente (S1); el segundo sustrato se consideró el control ya que consistió en sedimentos de la Ciénega del Rio Lerma (S2). Para evaluar un método de desinfección adecuado se estableció un diseño de bloques completos al azar en donde los tratamientos consistieron en: lavados+ etanol al 70%+ cloro comercial (T1) y lavados+ microdin-jabón líquido+ etanol al 70%+ cloro comercial (T2). Las condiciones de fotoperiodo (luz y oscuridad) representaron los bloques del diseño experimental. Resultados: En el experimento de tipo de sustrato se obtuvieron diferencias estadísticas significativas (P0.05). El T2 presento el menor porcentaje de contaminación 31.25%. Limitaciones del estudio/implicaciones: los resultados presentados son avances de un experimento a largo plazo. Hallazgos/conclusiones: El acondicionamiento de plantas madre de S. macrophylla es favorable en condiciones de invernadero en un sustrato compuesto por tierra negra y agrolita 2:1 permitiendo brotes nuevos y sanos. El mejor método de desinfección consistió en un enjuague a chorro de agua con jabón en polvo, 30 minutos con 100 ml de agua destilada más una gota de microdin comercial y dos de jabón líquido, dos minutos en agitación constante en etanol al 70% y 20 minutos en cloro comercial (6%) al 30% v/v, utilizando como explantes las yemas axilares de los tubérculos sin importar el fotoperiodo en el cuarto de incubación.

Introducción: El borrego cimarrón (BC) y venado bura (VB) son las especies cinegéticas más importantes en el noroeste de México, sus poblaciones pueden ser afectadas por deficiencias de micro-minerales. Objetivo: Determinar la concentración de los micro-minerales Fe, Cu, Zn, Se, Mn, Co y Cr en hígado como indicadoras de deficiencias/excesos en BC y VB. Materiales y métodos: El estudio se realizó en la UMA “Rancho Noche Buena”, Hermosillo, Sonora, México. A tres BC y cinco VB se les tomaron muestras de hígado. Los micro-minerales se determinaron en espectrómetro de masas con plasma acoplado inductivamente cuadrupolo (ICP-MS) y los análisis se validaron utilizando una muestra de referencia. Resultados: En BC los contenidos promedio de Fe, Cu, Zn, Se, Mn, y Cr fueron de 114.8, 60.9, 63.8, 1.1, 2.6, y 0.15 mgkg-1, y en VB de 183.9, 28.9, 44.6, 1.2, 2.6, y 0.17 mgkg-1, respectivamente, los cuales son adecuados para animales sanos. Sin embargo, una muestra de BC y dos de VB presentaron deficiencias de Cu, y 60% de los VB de Zn. Asimismo, los contenidos de Co en BC y VB fueron 14.6 y 12.3% inferiores al nivel adecuado. Conclusiones: En BC (n=3) los contenidos de Fe, Zn, Se y Mn fueron adecuados y el Cu fue parcialmente adecuado, en una muestra fue deficiente. En VB, los contenidos de Fe, Se y Mn fueron adecuados. Los contenidos de Cu y Zn fueron parcialmente adecuados en el 40 y 60% de los VB, donde estuvieron en nivel de deficiencia. El Co fue deficiente en ambas especies. Palabras clave: Diagnóstico; microelementos; deficiencias, borrego cimarrón, venado bura.

Objetivo: Describir los atributos morfologicos y etapas de imbibición en semillas de tres accesiones de Matthiola incana. Diseño/metodología/aproximación: Fueron analizadas semillas de los genotipos Nieve, Rosita y Uva correspondientes genero Matthiola especie incana. En una primera evaluación se calculó el peso de mil semillas y, determino el color de las mismas. A través del procesamiento de imágenes digitales se determinó el área, perímetro, longitud (eje mayor), ancho, ángulo, elongación (longitud/ancho) y el grado de redondez; datos que fueron analizados en una prueba de comparación de medias por Tukey. En la imbibición se colocaron en remojo muestras de cincuenta semillas de cada genotipo y fueron evaluadas cada 24, 48, 72 y 164 h para conocer su dinámica de absorción y poder determinar el tiempo en que transcurren las sub y fases de imbibición. Resultados: La descripción física en semillas de Nieve muestra que son de color naranja moderado y el peso de mil semillas es de 0.218 g; en Rosita la semilla es de color amarillo anaranjado moderado y mil semillas pesan 0.1902; el color en semillas de Uva es grisáceo a café obscuro con un peso de 0.1272 g a mil semillas. En las dimensiones morfológicas Nieve muestra mayores dimensiones respecto a Rosita y Uva; pero entre los tres genotipos muestran semejanzas en el tipo de forma. Durante la prueba de imbibición cada genotipo sigue su ritmo hasta la fase tres, donde el comportamiento se sincroniza en la visión de la protuberancia radicular a las 164 h de iniciada la prueba. Limitaciones del estudio/implicaciones: Las semillas muestran diferente tamaño, por lo cual manipular muestras grandes se complica al momento de la imbibición. Hallazgos/conclusiones: De las tres accesiones se determina que semillas correspondientes a la especie incana, son de mayores atributos morfológicos que otras especies del mismo género. En la fase dos, se identificaron dos subfases, la primera reconocida como el momento de expulsión de solutos y la segunda como recuperación a los solutos perdidos.

El tecolote moteado mexicano (Strix occidentalis lucida) es una especie amenazada en Estados Unidos y México, la falta de estudios en todo su ámbito de distribución y la creciente pérdida de hábitat, limita su conservación. El objetivo de este estudio fue estimar la distribución potencial de esta especie en una porción del centro de México. Para ello, se usó el algoritmo Maxent y el software ArcMap utilizando 21 registros de presencia del tecolote, 19 capas bioclimáticas, 4 capas del modelo digital de elevación, una de cobertura, y una de vegetación y uso de suelo. La cobertura, vegetación, elevación, precipitación y temperatura fueron las variables que más explicaron el modelo de distribución potencial. Zacatecas presentó la mayor superficie con muy alta probabilidad de distribución. Maxent parece ser una herramienta útil para definir la distribución de Strix occidentalis lucida; sin embargo, para validar sus resultados, es necesario comprobar en campo la presencia de esta especie en los sitios indicados por este modelo.

Objetivo: evaluar la sustentabilidad económica del cultivo de maíz criollo (Zea mays L.) en Acambay, Estado de México. Diseño/metodología/aproximación: El área de estudio fue el municipio de Acambay, del estado de México. Se aplicó un cuestionario a 50 productores de maíz de los ejidos y comunidades agrarias de la Soledad, Pueblo Nuevo, Loma Linda, Dateje, San Pedro de los Metales, Dongú y Tixmadeje. El cuestionario se basó en el método de Indicadores de Sustentabilidad de Explotaciones Agropecuarias (IDEA). La selección de cada productor encuestado se realizó mediante el muestreo tipo bola de nieve, escogiendo el primer encuestado al azar. Resultados: El valor obtenido para el indicador “viabilidad económica” (C1) fue 1 de 20 puntos, indicando que la ganancia derivada del cultivo de maíz representa un salario mínimo. El indicador “tasa de especialización económica” (C2) obtuvo 0 puntos ya que solo se cultiva maíz, por lo tanto, representa una fuente de ingreso para los productores. En el indicador “autonomía financiera” (C3) el valor promedio obtenido fue 12 explicando que no existe una dependencia marcada en la compra de insumos externos para cultivar maíz. El indicador “sensibilidad a las ayudas del primer pilar de la política agrícola común” (C4) obtuvo 0 en promedio ya que la mayoría de los productores no reciben apoyos gubernamentales para cultivar maíz. Limitaciones del estudio/implicaciones: los resultados presentados son avances de un análisis con más encuestados, por lo tanto, se sugiere tomar con cautela los resultados. Los indicadores “transmisión del capital” (C5) y “eficiencia de los procesos productivos” (C6) no se evaluaron adecuadamente ya que durante la aplicación de las encuestas los productores se negaron a proporcionar información detallada para evaluar estos indicadores. Hallazgos/conclusiones: la sustentabilidad económica calculada para los productores encuestados fue de 13% lo cual es muy baja, esto se debe principalmente a que éstos no siempre cuentan con el acceso a apoyos aplicables a la producción de maíz, otro factor que contribuye a la baja sustentabilidad es que el grano de maíz y los subproductos no se venden debido a bajos precios del mercado, por lo tanto, prefieren sembrar para autoconsumo, o para que los terrenos de cultivo heredados no estén ociosos.