Agronomic biofortification with selenium improves the yield and nutraceutical quality in tomato under soilless conditions

Selenium (Se) is an essential element for humans. Its consumption comes from food of animal or vegetal origin; whose content varies widely depending on its availability in soil or anthropogenic sources. Biofortification improves food nutritional quality, and its consumption has a positive influence in human health. Thus, the objective of this research was to assess agricultural biofortification with Se in tomato fruit and its effects on yield, nutraceutical quality, and antioxidant capacity.  Five Se doses (0, 2, 4, 6, and 8 mg L-1) in the form of sodium selenite (Na2SeO3) were added in a nutritional solution in a hydroponic system.  The results obtained indicated that agricultural biofortification with Se applied in the nutritional solution improved yield, nutraceutical quality, and Se concentration in tomato fruit. The optimum Se dose that maximized yield and nutraceutical quality, as well as the recommended consumption concentration in tomato fruit in this study was 2 mg L-1 (Na2SeO4) because higher doses decreased yield and bioactive compound biosynthesis. Incorporating Se in the nutritional solution is an alternative to increase phytochemical compound biosynthesis in tomato fruit and yield with the possibility of improving public health with its consumption

Detección de Ralstonia solanacearum en Solanum tuberosum L. en el Estado de Sonora, México

Ralstonia solanacearum (Rs) causes the disease quarantine called bacterial wilt in potatoes. Mexico importseed from United States of America (USA) and Canada, which is a significant aspect to eventual introduction of the disease in areas with large tracts of potato. Sonora is an important region in relation to potato production. Therefore, this research was conducted, with the following objectives: a) production of antibody for Rs; b) diagnosis of Rs in foreign tuber, and in tuber for human consumption which is used for seed; c) detection of Rs in vegetative growth of potato lots in Sonora, Mexico. We analyzed seed, seedling, leaf and tuber; the detection methods used were: specific means, ELISA, antiserum produced and pathogenicity tests. The positive results have shown the presence of Rs in tubers for consumption; in foreign tuber and vegetative stages it was negative. The separate testing should not be used as a unique method of detection; the presence of Rs, represents a risk of eventual manifestation of the disease, so it is necessary to undertake activities with preventive phytosanitary control.Ralstonia solanacearum (Rs) produce la enfermedad cuarentenaria denominada marchitez bacteriana en papa. México es un país importador de semilla de Estados Unidos de América y Canadá, aspecto significante para provocar una eventual introducción de esta enfermedad en áreas con amplias extensiones de papa. Sonora es una región importante en relación con la producción de este cultivo. Por lo anteriormente expuesto, se realizó la presente investigación, teniendo como objetivos: a) la producción de antisuero para la bacteria Rs; b) diagnosticar Rs en tubérculos de importación que se utilizan para siembra, y en tubérculos de procedencia mexicana para consumo humano, que son utilizados como semilla; c) la detección de la bacteria durante el desarrollo vegetativo de lotes de papa en Sonora, México. Se analizó tubérculo semilla de importación, de consumo humano, plantas de papa, hojas y tubérculos de producción; los métodos de detección utilizados fueron medios de cultivos específicos, ELISA, antisuero producido y pruebas de patogenicidad. Los resultados mostraron positiva la presencia de Rs en tubérculos de consumo; en tubérculos de importación y en etapas vegetativas fue negativa. Cada prueba de detección por separado no debe ser utilizada como método único; la presencia de Rs representa un riesgo de eventual manifestación de la enfermedad, por lo que es necesario que las áreas productoras realicen actividades de control preventivo fitosanitario

Solidaridad en la relación tutorial

Introducción. La tutoría académica concreta el proceso educativo sustentado en estándares de calidad, características y necesidades de aprendizaje del estudiante; se desenvuelve confrontando actividades pedagógicas y consolida solidaridades. En este contexto, el estudio se realizó con el propósito de realizar la analítica de la solidaridad que surge de la relación tutorial. Método. Desde el ámbito de la hermenéutica, se realizó un estudio en cuatro fases: analítica, comprensiva, reconstructiva, crítica. Se construyó el concepto de solidaridad en la relación tutorial con propuestas de Gadamer, Habermas, Adela Cortina y Edgar Morín. Las categorías de análisis fueron: construcción social del sentido en la relación tutorial, relación tutorial de naturaleza epistémica, compleja, infinita y cambiante; y práctica tutorial generadora de solidaridades. Resultados. La solidaridad como praxis humana orientada al cuidado del otro (Fürsorge) promueve el encuentro con el estudiante. La tutoría académica regula la experiencia vital de la dualidad enseñar-aprender; articula la decisión del docente y alumno con la responsabilidad solidaria. El docente concreta un asentimiento aconsejado por la amistad de estar-ahí-con el estudiante, acompañándolo, posibilitando elecciones y decisiones entre posibilidades para una vida sustentable mediante la virtud de la phrónesis. Conclusiones. La solidaridad en la relación tutorial como horizonte de sentido engarza la cosmovisión del binomio docente-estudiante en la relación tutorial. Dado el vínculo social, se ubica en el escenario de la relación tutorial el sentido originario de la amistad y la solidaridad con los siguientes baremos: compasión, saber hacer, confidencialidad, confianza, conciencia de sí mismo y del otro, tacto, escucha atenta y solícita, comprensión del otro

Aquaculture—Production System and Waste Management for Agriculture Fertilization—A Review

Aquaculture is the fastest growing animal food production sector worldwide and is becoming the main source of aquatic animal foodstuff for human consumption. However, the aquaculture sector has been strongly criticized for its environmental impacts. It can cause discharge and accumulation of residual nutrients in the areas surrounding the production farms. This is because, of the total nutrients supplied to production ponds, only 30% are converted into product, while the rest is usually discharged into the environment to maintain water quality in aquaculture culture systems, thereby altering the physic-chemical characteristics of the receiving water. In contrast, this same accumulation of nutrients is gaining importance within the agricultural sector, as it has been reported that the main nutrients required by plants for their development are found in this aquaculture waste. The purpose of this review article is to indicate the different aquaculture production systems, the waste they generate, as well as the negative effects of their discharge into the environment. Biofiltration and bioremediation processes are mentioned as alternatives for aquaculture waste management. Furthermore, the state of the art in the treatment and utilization of aquaculture waste as a mineral source for agricultural nutrition through biodigestion and biomineralization processes is described. Finally, aquaponics is referred to as a biological production approach that, through efficient use of water and recycling of accumulated organic nutrients in aquaculture systems, can contribute to addressing the goals of sustainable aquaculture development

Detection of Ralstonia solanacearum in Solanum tuberosum L. in Sonora, Mexico

Ralstonia solanacearum (Rs) produce la enfermedad cuarentenaria denominada marchitez bacteriana en papa. México es un país importador de semilla de Estados Unidos de América y Canadá, aspecto significante para provocar una eventual introducción de esta enfermedad en áreas con amplias extensiones de papa. Sonora es una región importante en relación con la producción de este cultivo. Por lo anteriormente expuesto, se realizó la presente investigación, teniendo como objetivos: a) la producción de antisuero para la bacteria Rs; b) diagnosticar Rs en tubérculos de importación que se utilizan para siembra, y en tubérculos de procedencia mexicana para consumo humano, que son utilizados como semilla; c) la detección de la bacteria durante el desarrollo vegetativo de lotes de papa en Sonora, México. Se analizó tubérculo semilla de importación, de consumo humano, plantas de papa, hojas y tubérculos de producción; los métodos de detección utilizados fueron medios de cultivos específicos, ELISA, antisuero producido y pruebas de patogenicidad. Los resultados mostraron positiva la presencia de Rs en tubérculos de consumo; en tubérculos de importación y en etapas vegetativas fue negativa. Cada prueba de detección por separado no debe ser utilizada como método único; la presencia de Rs representa un riesgo de eventual manifestación de la enfermedad, por lo que es necesario que las áreas productoras realicen actividades de control preventivo fitosanitario.Ralstonia solanacearum (Rs) causes the disease quarantine called bacterial wilt in potatoes. Mexico importseed from United States of America (USA) and Canada, which is a significant aspect to eventual introduction of the disease in areas with large tracts of potato. Sonora is an important region in relation to potato production. Therefore, this research was conducted, with the following objectives: a) production of antibody for Rs; b) diagnosis of Rs in foreign tuber, and in tuber for human consumption which is used for seed; c) detection of Rs in vegetative growth of potato lots in Sonora, Mexico. We analyzed seed, seedling, leaf and tuber; the detection methods used were: specific means, ELISA, antiserum produced and pathogenicity tests. The positive results have shown the presence of Rs in tubers for consumption; in foreign tuber and vegetative stages it was negative. The separate testing should not be used as a unique method of detection; the presence of Rs, represents a risk of eventual manifestation of the disease, so it is necessary to undertake activities with preventive phytosanitary control.Fil: Alvarado-Martínez, Ana G.. Universidad Autónoma de Baja California. Instituto de Ciencias Agrícolas.Fil: Rueda-Puente, Edgar O.. Universidad Autónoma de Baja California. Departamento de Ciencias Agropecuarias.Fil: Ponce-Medina, Juan F.. Universidad Autónoma de Baja California. Departamento de Ciencias Agropecuarias.Fil: Avendaño-Reyes, Leonel. Universidad Autónoma de Baja California. Departamento de Ciencias Agropecuarias.Fil: Santillano-Cazares, Jesús. Universidad Autónoma de Baja California. Departamento de Ciencias Agropecuarias.Fil: Borboa-Flores, Jesús. Universidad de Sonora. Departamento de Agricultura y Ganadería.Fil: Hernández-Montiel, Luis. La Paz (Baja California Sur, México). Centro de Investigaciones Biológicas del Noroeste.Fil: Holguín-Peña, Ramón. La Paz (Baja California Sur, México). Centro de Investigaciones Biológicas del Noroeste

QSTR Modeling to Find Relevant DFT Descriptors Related to the Toxicity of Carbamates

Compounds containing carbamate moieties and their derivatives can generate serious public health threats and environmental problems due their high potential toxicity. In this study, a quantitative structure–toxicity relationship (QSTR) model has been developed by using one hundred seventy-eight carbamate derivatives whose toxicities in rats (oral administration) have been evaluated. The QSRT model was rigorously validated by using either tested or untested compounds falling within the applicability domain of the model. A structure-based evaluation by docking from a series of carbamates with acetylcholinesterase (AChE) was carried out. The toxicity of carbamates was predicted using physicochemical, structural, and quantum molecular descriptors employing a DFT approach. A statistical treatment was developed; the QSRT model showed a determination coefficient (R2) and a leave-one-out coefficient (Q2LOO) of 0.6584 and 0.6289, respectively

Chalcones as positive allosteric modulators of α7 nicotinic acetylcholine receptors: A new target for a privileged structure

The α7 acetylcholine nicotine receptor is a ligand-gated ion channel that is involved in cognition disorders, schizophrenia, pain and inflammation among other diseases. Therefore, the development of new agents that target this receptor has great significance. Positive allosteric modulators might be advantageous, since they facilitate receptor responses without directly interacting with the agonist binding site. Here we report the search for and further design of new positive allosteric modulators having the relatively simple chalcone structure. From the natural product isoliquiritigenin as starting point, chalcones substituted with hydroxyl groups at defined locations were identified as optimal and specific promoters of α77 nicotinic function. The most potent compound (2,4,2-2,5-2-tetrahydroxychalcone, 111) was further characterized showing its potential as neuroprotective, analgesic and cognitive enhancer, opening the way for future developments around the chalcone structure.Peer Reviewe