733 research outputs found
Conidios en la atmósfera de la ciudad de Mérida
XV lnternational A.P.L.E. Symposium of Palynolog
N, P, K nutrition differentially affects the incidence and severity of the attack of pests and diseases in plants
Objective: To document and analyze relevant results reported on the relationships kept by the essential elements, nitrogen (N), phosphorus (P), and potassium (K) with biotic stress factors in higher plants.
Design/methodology/approach: A bibliographic analysis was carried out using keywords related to the concepts of nutrient relationship with phytopathogens, plant fertilization and nutrition and biotic stress. Subsequently, the most relevant articles on N, P, and K and their relationship with pests and diseases were selected and analyzed.
Results: The elements N, P, and K affect the development of pests on plants. Fertilization with N tend to increase the presence of pests, while fertilization with P and K decreases it. However, this cannot be generalized for all crops or pests.
Limitations/implications of the study: Research on the effects of N, P, and K on the incidence of phytopathogens is limited and in most cases the mechanisms that determine such relashionship are not described.
Findings/conclusions: Fertilization with N causes a higher incidence of pests and diseases in plants, while fertilization with P and K can contribute to reduce their incidence. However, due to the great diversity of responses, these statements are not applicable to all cases and depend on other factors such as the crop and the pest present in the agroecosystem. It is required to carry out studies that make it possible to clarify exactly how these essential elements influence the development of diseases in different crops, and thus be able to make nutrition recommendations in which limiting biotic factors are taken into account
PATRONES DE LA MACROFAUNA EDAFICA EN UN CULTIVO DE ZEA MAIZ DURANTE LA FASE POSTCOSECHA EN LA MANCHA, VERACRUZ, MEXICO
The soil macrofauna of a cornfield was studied during the fallow period in El Centro de Investigaciones Costeras "La Mancha", Veracruz. Patterns of soil macrofauna density, spatial distribution and diversity were described and their relationships with soil temperature, moisture, organic matter and pH were explored. Four strategies were combined to undertake this aim: a) sampling of soil macrofauna was carried out in seven ten cm soil layers from 0 to 70 cm depth; b) soil macrofauna was identified to morphospecies level; c) the size of morphospecies aggregations was determined following a the two-term local quadrat variance method (TTLQV); d) analysis of canonical correspondence was used to arrange morphospecies distribution in an spatial and environmental framework of reference. Density of soil macrofauna in the studied site seems to be the lowest value ever recorded in similar studies (246 individuals m-2). Forty-six morphospecies were collected that are mainly distributed in the top 20 cm soil layer and present an aggregated horizontal pattern of distribution. The diameter of aggregations of Oligochaeta juveniles, larvae of Tenebrionidae and Diplopoda juveniles was >1.5m, 0.9 m and 1.2 m respectively. It was possible to arrange different groups of soil Macrofauna according with their ranges of tolerance to environmental variables. Therefore, it is suggested that these patterns do reflect preferences of soil biota to microenvironments and do respond to soil degradation.Estudiamos la macrofauna del suelo de un cultivo de Zea maiz durante la fase postcosecha en el Centro de Investigaciones Costeras La Mancha, Veracruz. Describimos patrones de densidad, distribución espacial y diversidad en relación con la temperatura, humedad y pH del suelo. Para esto conjuntamos cuatro estrategias: a) muestreamos la macrofauna en estratos de 10 cm hasta los 70 cm de profundidad; b) separamos la fauna a nivel de morfoespecie; c) estimamos el tamaño de las agregaciones de las morfoespecies mediante una técnica de cuadrante-varianza; y d) ordenamos, mediante un análisis de correspondencia canónica, morfoespecies y estratos en un marco de referencia ambiental. La densidad de la macrofauna del suelo estudiado es la más baja reportada hasta la fecha para agroecosistemas en el mundo (246 individuos/m2). Colectamos 46 morfoespecies, que se distribuyeron generalmente en el primer o segundo estrato del suelo y presentaron una distribución agregada. El diametro de las agregaciones de los Oligochaeta juveniles fue superior a 1.5 m y para las larvas de Tenebrionidae y los Diplopoda juveniles fue de 0.9 y 1.2 m, respectivamente. Debido a que es posible separar distintos grupos de acuerdo con sus rangos de tolerancia a la temperatura, pH, humedad y materia orgánica en el suelo, es factible que los patrones de distribución registrados sean un reflejo de las preferencias de la biota a diferentes microambientes y al estado de degradación del suelo
Hilando generaciones y moda
En el proyecto PAP llamado Hilando Generaciones y Moda del cual se presenta este reporte del periodo otoño 2022, el propósito general fue el de crear espacios en los cuales se diera paso a la colaboración intergeneracional e intercultural a través de la
capacitación en costura y diseño de modas. Un espacio en donde los participantes pudieran intercambiar conocimientos, diálogos y trabajar en equipo, pero, sobre todo, mostrando empatía, confianza e interactuando mientas se conocen los estudiantes y las personas mayores. En este periodo escolar se elaboraron prendas de vestir para el uso personal y familiar de las personas mayores, se llevó a cabo una sesión fotográfica con las personas mayores, una pasarela para la exposición de las prendas, un documental y una revistacatálogo con las prendas. Las primeras sesiones se dedicaron a la sensibilización de los alumnos para con la población de personas mayores y con esto se dio pie para la interacción y convivencia entre los estudiantes y personas mayores, principalmente en las instalaciones del Centro Tapatío de atención al Adulto Mayor (CETAM) y en uno de los centros de día del DIF. Los estudiantes estuvieron interactuando con las personas mayores, en los que se generó una relación profunda de comprensión y empatía, y se crearon importantes resultados como las prendas, una capa tejida por alumnos y personas mayores, revistacatálogo, pasarela y un visible entramado entre las dos generaciones: jóvenes y personas mayores.ITESO, A.C
Population Characteristics of Rattus rattus and Mus musculus present in rural communities in Yucatán, México
The aim of this study was to describe the abundance, weight and body length structures, and reproductive and health status of the black rat Rattus rattus and the house mouse Mus musculus from Yucatán, México. Rodents were trapped from May to September 2016 in rural households in the communities Xkalakdzonot (XKA) and Paraíso (PAR). A total of 236 M. musculus and 127 R. rattus were trapped over 3880 trap-nights. In XKA, R. rattus was more abundant than M. musculus, whereas in PAR, M. musculus was notably dominant over R. rattus. The sex ratio was 1:1 in both rodent species. Rattus rattus in classes 40.1?80 g and 120?139 mm were more abundant, whereas M. musculus in classes 8.1?12 g and 70?79 mm were more abundant. Mus musculus had similar weight, body length and reproductive and health parameters between communities. The majority of specimens of trapped rodents had a good body condition and few individuals had wounds. The information generated in this study is basic for understanding the ecology of commensal rodents, the dynamics of rodent-associated zoonosis transmission, and to design of integrated control programs for rodents.Fil: Panti May, Jesús Alonso. Universidad Autonoma de Yucatan; MéxicoFil: Gurubel González, Yessica M.. Universidad Autonoma de Yucatan; MéxicoFil: Palomo Arjona, Eduardo E.. Universidad Autonoma de Yucatan; MéxicoFil: Cetina Trejo, Rosy C.. Universidad Autonoma de Yucatan; MéxicoFil: Machain Williams, Carlos. Universidad Autonoma de Yucatan; MéxicoFil: Robles, Maria del Rosario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; ArgentinaFil: Hernández Betancourt, Silvia F.. Universidad Autonoma de Yucatan; Méxic
Blood-based epigenome-wide analyses of cognitive abilities
BACKGROUND: Blood-based markers of cognitive functioning might provide an accessible way to track neurodegeneration years prior to clinical manifestation of cognitive impairment and dementia. RESULTS: Using blood-based epigenome-wide analyses of general cognitive function, we show that individual differences in DNA methylation (DNAm) explain 35.0% of the variance in general cognitive function (g). A DNAm predictor explains ~4% of the variance, independently of a polygenic score, in two external cohorts. It also associates with circulating levels of neurology- and inflammation-related proteins, global brain imaging metrics, and regional cortical volumes. CONCLUSIONS: As sample sizes increase, the ability to assess cognitive function from DNAm data may be informative in settings where cognitive testing is unreliable or unavailable. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s13059-021-02596-5
Oxidative stress biomarkers and their relationship with cytokine concentrations in overweight/obese pregnant women and their neonates
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