Cambios bioquímicos y fisiológicos durante la maduración de frutos de zapote negro (Diospyros digyna jacq.)

El objetivo de este trabajo fue estudiar los principales cambios relacionados con el proceso de maduración de frutos de zapote negro (Diospyros digyna Jacq.) a 25±2 °C de temperatura y 65 a 70% de humedad relativa por un periodo de seis días. Los frutos presentaron un comportamiento climatérico, definido por un aumento significativo de la velocidad de respiración y producción de etileno, que alcanzaron su máximo a los 6 y 5 d después de la cosecha; la autocatálisis de etileno quedó establecida por el incremento significativo en la actividad de la enzima ACC-oxidasa, cuyo máximo antecedió al de etileno en 1 d. El proceso de ablandamiento inicial de los frutos estuvo asociado a la reducción en la firmeza desde 31.5 N a la cosecha hasta 3.8 N en el d 6, así como a una alta actividad de la enzima pectinmetilestearasa (PME). Hubo un incremento constante en concentración de carotenoides hasta el d 4 para después disminuir como resultado de un proceso de oxidación, coincidiendo con la disminución de ácido ascórbico de 180.7 a 69.8 mg 100 g-1 en el d 6. Los compuestos fenólicos fueron oxidados por la enzima polifenoloxidasa (PFO), contribuyendo así al típico color negro-café de la pulpa

Maduración y calidad de frutos de mango ‘Kent’ con tres niveles de fertilización

The annual fertilization program plays an important role in the management of the garden and its efficiency depend largely, production and fruit quality. A balanced fertilization consider the amount of nutrients available in the soil, including those used by the tree for their development and they are removed by the production of fruit, ensuring adequate supply of macro and micro elements. The objective of this research was to evaluate the effect of fertilization program on changes in the variables related to the maturation and fruit quality of mango ‘Kent’ from an experiment installed in a commercial orchard in Acaponeta, Nayarit, Mexico, where three levels of fertilization were applied (g tree-1): regular (381 de N, 367 de P2O5, 296 de K2O, 296, 688 Ca, 84 Mg, Fe 14, 9 Mn, 5 Zn and 45 B), high (50% more of each element of the regular dose) and control (without fertilization). The fertilization affected the nutrient concentration of fruit. Differences were presented in profiles the total respiratory rate, firmness, soluble solids (TSS), citric acid, ascorbic acid and sugar/acid ratio also the presence of nitrogen in levels of regular and high fertilization increased the green hue of the background colour of the fruits. It was concluded that the quality and shelf life of fruits was affected by fertilization levels applied.El programa anual de fertilización juega un papel importante en el manejo del huerto y de su eficiencia dependen, en gran medida, la producción y calidad de los frutos. Una fertilización balanceada considera la cantidad de nutrientes disponibles en el suelo, incluyendo los que utiliza el árbol para su desarrollo y los que son removidos por la producción de fruto, lo que asegura el suministro adecuado de macro y micro elementos. El objetivo de esta investigación fue evaluar el efecto del programa de fertilización sobre los cambios en las variables relacionadas con la maduración y calidad de frutos de mango ‘Kent’, a partir de un experimento instalado en un huerto de comercial en Acaponeta, Nayarit, México, donde se aplicaron tres niveles de fertilización ((g árbol-1): normal (381 de N, 367 de P2O5, 296 de K2O, 688 de Ca, 84 de Mg, 14 de Fe, 9 de Mn, 5 de Zn y 45 de B), alta (50% más de cada elemento de la dosis normal) y control (sin fertilización). Las dosis de fertilización afectaron la concentración nutrimental del fruto. Se presentaron diferencias en los perfiles de la intensidad respiratoria, firmeza, sólidos solubles totales (SST), ácido cítrico, ácido ascórbico y relación azúcar/ácido, asimismo, la presencia de nitrógeno en los niveles de fertilización normal y alta, aumentó la tonalidad verde del color de fondo de los frutos. Se concluyó que, la calidad y vida de anaquel de los frutos fue afectada por los niveles de fertilización aplicados

Nitrogen and potassium nutrition differentially affect tomato biomass and growth

We evaluated the effect of nitrogen and potassium nutrition on phenological stages on the vegetative biomass production and growth of tomato cultivated hydroponically. Nitrogen concentrations of 10, 12, 14, and 16molcm-3 in the vegetative stage were evaluated, while potassium concentrations of 5, 7, 9, 11, and 13molcm-3 were evaluated for the reproductive stage. In the vegetative stage, the addition of N caused significant differences in the vegetation dry biomass (VDB), with the largest responses observed at concentrations of 14 and 16molcm-3. For the reproductive stage, a significant response was only observed for K. The 5-13molcm-3 increases in the K concentration raised the VDB. Growth (net assimilation rate NAR, relative growth rate RGR, and crop growth rate CGR) was characterized by a quadratic behavior in the vegetative stage. In the reproductive stage, NAR and RGR exhibited an asymptotic negative trend, while CGR exhibited a positive quadratic trend. Nitrogen and potassium positively affected the growth variables evaluated in the vegetative and reproductive stages, increasing the productive potential of hydroponically cultivated tomato

Rendimiento, calidad y comportamiento poscosecha de frutos de aguacate ‘Hass’ de huertos con diferente fertilización

In fruit trees, productivity differs between orchards due to the particular condition of the nutritional status of trees, soil fertility, rootstock, crop health and agronomic management. The objective of this research was to compare the yield, quality and post-harvest behavior of ‘Hass’ avocado fruits in two orchards with different fertilization management. The first was located in Valle de Bravo and the second in Villa de Allende, State of Mexico. The evaluation was carried out in 2017. In each orchard the yield, quality, post-harvest behavior and extraction of nutrients by the fruits were measured. In addition, the tree's nutritional status and soil fertility were diagnosed. The fruits of the Valle de Bravo orchard surpassed those of Villa de Allende in yield, weight, length, diameter and oil concentration and density, however, they had less firmness and weight loss. The avocados of Valle de Bravo had higher concentration of K, S, Zn and B, those of Villa de Allende concentrated more Ca, Fe, Cu and Mn. In Valle de Bravo the trees showed deficiencies of Ca, S, Cu, Mn, Zn and B, while, in Villa de Allende, the deficient elements were K, S, Zn and B. In conclusion, the highest yield of fruit obtained in the Valle de Bravo orchard was related to the better nutritional status of the trees and increased soil fertilityEn frutales, la productividad difiere entre huertos debido a la condición particular del estatus nutrimental de los árboles, fertilidad del suelo, portainjerto, sanidad del cultivo y manejo agronómico. El objetivo de esta investigación fue comparar el rendimiento, calidad y comportamiento poscosecha de frutos de aguacate ‘Hass’ en dos huertos con diferente manejo de la fertilización. El primero se ubicó en Valle de Bravo y el segundo en Villa de Allende, Estado de México. La evaluación se realizó en 2017. En cada huerto se midió el rendimiento, calidad, comportamiento poscosecha y extracción de nutrimentos por los frutos. Además, se diagnosticó el estatus nutrimental del árbol y la fertilidad del suelo. Los frutos del huerto de Valle de Bravo superaron a los de Villa de Allende en rendimiento, peso, longitud, diámetro y concentración y densidad de aceite, sin embargo, presentaron menor firmeza y pérdida de peso. Los aguacates de Valle de Bravo tuvieron mayor concentración de K, S, Zn y B, los de Villa de Allende concentraron más Ca, Fe, Cu y Mn. En Valle de Bravo los árboles mostraron deficiencias de Ca, S, Cu, Mn, Zn y B, mientras que, en Villa de Allende, los elementos deficientes fueron K, S, Zn y B. En conclusión, el mayor rendimiento de fruto obtenido en el huerto de Valle de Bravo se relacionó con el mejor estatus nutrimental de los árboles y mayor fertilidad del suelo

Nitrogen and potassium nutrition differentially affect tomato biomass and growth

We evaluated the effect of nitrogen and potassium nutrition on phenological stages on the vegetative biomass production and growth of tomato cultivated hydroponically. Nitrogen concentrations of 10, 12, 14, and 16molcm-3 in the vegetative stage were evaluated, while potassium concentrations of 5, 7, 9, 11, and 13molcm-3 were evaluated for the reproductive stage. In the vegetative stage, the addition of N caused significant differences in the vegetation dry biomass (VDB), with the largest responses observed at concentrations of 14 and 16molcm-3. For the reproductive stage, a significant response was only observed for K. The 5-13molcm-3 increases in the K concentration raised the VDB. Growth (net assimilation rate NAR, relative growth rate RGR, and crop growth rate CGR) was characterized by a quadratic behavior in the vegetative stage. In the reproductive stage, NAR and RGR exhibited an asymptotic negative trend, while CGR exhibited a positive quadratic trend. Nitrogen and potassium positively affected the growth variables evaluated in the vegetative and reproductive stages, increasing the productive potential of hydroponically cultivated tomato

Deep Multi-OMICs and Multi-Tissue Characterization in a Pre- and Postprandial State in Human Volunteers: The GEMM Family Study Research Design

Cardiovascular disease (CVD) and type 2 diabetes (T2D) are increasing worldwide. This is mainly due to an unhealthy nutrition, implying that variation in CVD risk may be due to variation in the capacity to manage a nutritional load. We examined the genomic basis of postprandial metabolism. Our main purpose was to introduce the GEMM Family Study (Genetics of Metabolic Diseases in Mexico) as a multi-center study carrying out an ongoing recruitment of healthy urban adults. Each participant received a mixed meal challenge and provided a 5-hours’ time course series of blood, buffy coat specimens for DNA isolation, and adipose tissue (ADT)/skeletal muscle (SKM) biopsies at fasting and 3 h after the meal. A comprehensive profiling, including metabolomic signatures in blood and transcriptomic and proteomic profiling in SKM and ADT, was performed to describe tendencies for variation in postprandial response. Our data generation methods showed preliminary trends indicating that by characterizing the dynamic properties of biomarkers with metabolic activity and analyzing multi-OMICS data it could be possible, with this methodology and research design, to identify early trends for molecular biology systems and genes involved in the fasted and fed states

Replication of Integrative Data Analysis for Adipose Tissue Dysfunction, Low-Grade Inflammation, Postprandial Responses and OMICs Signatures in Symptom-Free Adults

We previously reported preliminary characterization of adipose tissue (AT) dysfunction through the adiponectin/leptin ratio (ALR) and fasting/postprandial (F/P) gene expression in subcutaneous (SQ) adipose tissue (AT) biopsies obtained from participants in the GEMM study, a precision medicine research project. Here we present integrative data replication of previous findings from an increased number of GEMM symptom-free (SF) adults (N = 124) to improve characterization of early biomarkers for cardiovascular (CV)/immunometabolic risk in SF adults with AT dysfunction. We achieved this goal by taking advantage of the rich set of GEMM F/P 5 h time course data and three tissue samples collected at the same time and frequency on each adult participant (F/P blood, biopsies of SQAT and skeletal muscle (SKM)). We classified them with the presence/absence of AT dysfunction: low (1) ALR. We also examined the presence of metabolically healthy (MH)/unhealthy (MUH) individuals through low-grade chronic subclinical inflammation (high sensitivity C-reactive protein (hsCRP)), whole body insulin sensitivity (Matsuda Index) and Metabolic Syndrome criteria in people with/without AT dysfunction. Molecular data directly measured from three tissues in a subset of participants allowed fine-scale multi-OMIC profiling of individual postprandial responses (RNA-seq in SKM and SQAT, miRNA from plasma exosomes and shotgun lipidomics in blood). Dynamic postprandial immunometabolic molecular endophenotypes were obtained to move towards a personalized, patient-defined medicine. This study offers an example of integrative translational research, which applies bench-to-bedside research to clinical medicine. Our F/P study design has the potential to characterize CV/immunometabolic early risk detection in support of precision medicine and discovery in SF individuals

Avocado Fruit Quality Management during the Postharvest Supply Chain

Avocados are a popular subtropical fruit of high economic importance, and the European Union is the biggest importer of the bulk of the fruit coming from countries such as South Africa, Chile, and Israel. The fruit is highly nutritious, being rich in vitamins A, B, C, minerals, potassium, phosphorus, magnesium, iron, and antioxidants. The biggest challenge is that the fruit is highly susceptible to qualitative and quantitative postharvest losses. Successful maintenance of avocado fruit quality during the supply chain depends on many aspects, including adequate orchard management practices, harvesting practices, packing operations, postharvest treatments, temperature management, transportation and storage conditions, and ripening at destination. Postharvest losses are mostly attributed to flesh softening, decay, physiological disorders, and improper temperature management. Management of the supply chain is solely done to provide the fruit with the most favorable conditions to extend storage life, and retain quality and nutritional attributes of the fruit. The focus of this review is therefore to study the findings that have emanated from research done to retain overall avocado fruit quality and to reduce postharvest losses during the supply chain through the adoption of appropriate and novel postharvest technologies.Post-Harvest Innovation Programme (Fresh Produce Exporter Forum, South Africa, and Department of Science and Technology).http://www.tandfonline.com/loi/lfri202015-06-30hb201