TENDENCIAS DE PRODUCCIÓN, MANEJO POSTCOSECHA Y COMERCIALIZACIÓN NACIONAL Y PARA EXPORTACIÓN DE NOPALITO (Opuntia ficus-indica)

The production and export of vegetables are some of the most important activities of the Mexican economy. The production of nopalito (young and succulent cladodes of the genera Opuntia and Nopalea) in Mexico has increased in recent decades and has been recognized as a vegetable with increased export potential. The objectives of the present study were to identify the trends of production, postharvest handling and national and international marketing of nopalito (Opuntia ficus-indica), to characterize the differences in postharvest handling according to the production destination and to know its dynamics as a horticultural crop in Mexico. The information was obtained from bibliographic sources, official statistics and questionnaires applied to producers and exporters in Otumba and San Martín de las Pirámides regions, Estado de Mexico. The information regarding national production, which destined to export and internal consumption, is scarce; in part, for lack of a specific tariff fraction for nopalito. The systems of production of nopalito in Mexico destined for export contrast with those that produce nopalito for national consumption in the resources assigned by the producer.Producción y exportación de hortalizas son algunas de las actividades más importantes de la economía mexicana. La producción de nopalito (cladodios jóvenes y, suculentos de los géneros Opuntia y Nopalea) en México ha aumentado en las últimas décadas y se ha reconocido como una hortaliza con incremento en el potencial de exportación. Los objetivos del presente estudio fueron identificar las tendencias de producción, manejo postcosecha y comercialización nacional y al extranjero del nopalito (Opuntia ficus-indica), caracterizar las diferencias en el manejo postcosecha de acuerdo con el destino de la producción y conocer su dinámica como cultivo hortícola en México. La información se obtuvo de fuentes bibliográficas, estadísticas oficiales y cuestionarios aplicados a los productores y exportadores de la región de Otumba y San Martín de las Pirámides, Estado de México. La información referente a la producción nacional, la destinada a exportación y al consumo interno, es escasa; en parte, por falta de una fracción arancelaria específica para nopalito. Los sistemas de producción de nopalito en México destinado a la exportación contrastan con los que producen nopalito para consumo nacional en los recursos asignados por el producto

Morphology, phenology and agronomic traits of two wild Mexican common bean (Phaseolus vulgaris L.) populations under cultivation

The objective of this research was to characterise two populations of wild bean grown simultaneously in an experimental field site in Chapingo, Mexico. For comparative purposes, two cultivars of common bean were included. Only seven of 24 phenological and morphological traits (e.g. number of days to emergence, expansion of primary leaves and third trifoliolate leaf, number of branches per plant, diameter of stem, number of flower buds per plant and nodes per branch) investigated were statistically similar between and within wild samples due largely to differences in growth habit. The number of inflorescences, leaves, pods and seeds per wild plant fluctuated between 72 and 145, 109 and 206, 68 and 284 and 180 and 513, respectively. In contrast, each cultivar was highly homogeneous. Principal component analyses supported the conclusion that these morphological and agronomic characteristics of wild common bean populations primarily depend on the predominant growth habit type and that under different environments, the expression of these traits may change

Repositioning of the global epicentre of non-optimal cholesterol

High blood cholesterol is typically considered a feature of wealthy western countries1,2. However, dietary and behavioural determinants of blood cholesterol are changing rapidly throughout the world3 and countries are using lipid-lowering medications at varying rates. These changes can have distinct effects on the levels of high-density lipoprotein (HDL) cholesterol and non-HDL cholesterol, which have different effects on human health4,5. However, the trends of HDL and non-HDL cholesterol levels over time have not been previously reported in a global analysis. Here we pooled 1,127 population-based studies that measured blood lipids in 102.6 million individuals aged 18 years and older to estimate trends from 1980 to 2018 in mean total, non-HDL and HDL cholesterol levels for 200 countries. Globally, there was little change in total or non-HDL cholesterol from 1980 to 2018. This was a net effect of increases in low- and middle-income countries, especially in east and southeast Asia, and decreases in high-income western countries, especially those in northwestern Europe, and in central and eastern Europe. As a result, countries with the highest level of non-HDL cholesterol—which is a marker of cardiovascular risk—changed from those in western Europe such as Belgium, Finland, Greenland, Iceland, Norway, Sweden, Switzerland and Malta in 1980 to those in Asia and the Pacific, such as Tokelau, Malaysia, The Philippines and Thailand. In 2017, high non-HDL cholesterol was responsible for an estimated 3.9 million (95% credible interval 3.7 million–4.2 million) worldwide deaths, half of which occurred in east, southeast and south Asia. The global repositioning of lipid-related risk, with non-optimal cholesterol shifting from a distinct feature of high-income countries in northwestern Europe, north America and Australasia to one that affects countries in east and southeast Asia and Oceania should motivate the use of population-based policies and personal interventions to improve nutrition and enhance access to treatment throughout the world.</p

Estudio comparativo de intercambio gaseoso y parámetros fotosintéticos en dos tipos de hojas de frijol (Phaseolus vulgaris L.) silvestre y domesticado

El objetivo de este estudio fue comparar el intercambio gaseoso y algunos parámetros de la fotosíntesis en hojas primarias y trifolioladas de plantas de frijol silvestre y domesticado en la etapa vegetativa inicial, con la finalidad de evidenciar la eficiencia fotosintética de las variantes silvestres. Muestras de dos poblaciones de frijol silvestre originarias de Durango y Tlaxcala, México, y los cultivares Amarillo y Bayo Mecentral se establecieron en invernadero. Se evaluó la conductividad estomática, tasa de asimilación de CO2 (PN), temperatura de la hoja, tasa transpiratoria, contenido de clorofila y algunos parámetros de la fluorescencia. El análisis de varianza mostró interacción estadísticamente significativa entre el tipo de hoja y la variante de frijol (frijol silvestre de Durango y Tlaxcala, México, y los cultivares Amarillo y Bayo Mecentral) para contenido de clorofila tipo a y b y el índice a/b, y la fluorescencia inicial, variable y máxima de la clorofila. Se observó amplia heterogeneidad entre y dentro de los materiales silvestres, independientemente de que la semilla fuera del mismo origen, la heterogeneidad también se observó entre los cultivares (Amarillo y Bayo Mecentral), es decir, se encontró una ampliavariabilidad interespecífica (entre especies) e intraespecífica (dentro de una misma especie). Se concluye que las hojas primarias y el folíolo central de la primera hoja trifoliolada tanto de las variantes silvestres como domesticadas, desarrolladas en un ambiente homogéneo, muestran diferencias significativas diversas entre y dentro de las variantes silvestres y entre las variantes silvestres y domesticadas que conducen a contrastes en PN

Influence of dry handling at two temperatures and stem length in vase life of rose ‘Polo’

The effect of room and refrigeration temperature and the length of the flower stem in vase life of rose ‘Polo’ was evaluated. Floral stems of 60 cm length were harvested and stored at 4 and 23 °C during 72 h in dry conditions. During storage, three stems were taken daily to determine the damage of the cell membrane. After storage, eight stems of each temperature were trimmed at 33, 41 and 54 cm in length and were placed in vases with 250 mL of tap water and randomized into an area with illumination of 10 μmol m-2 s-1, photoperiod of 12 h, average temperature of 23 ± 3 °C and 40 % of relative humidity (RH) to evaluate vase life (VL). The results indicated a direct relationship (R2 = 0.9835) between the number of vessels and stem length between 33 and 54 cm. The membrane cell damage was higher at 23° than at 4 °C. Stems stored at 23 °C decreased their fresh weight in the fourth day and their water absorption on day seven, they also had less flower opening and vase life compared to the stems stored at 4 °C. Dry storage at room temperature for 72 h only decreases from 11.5 to 9.4 days the VL of rose ‘Polo’, resulting in a good choice in places where the cold rooms do not exist; the short stems had higher water absorption but did not improve the VL

Heterogeneous contributions of change in population distribution of body mass index to change in obesity and underweight

From 1985 to 2016, the prevalence of underweight decreased, and that of obesity and severe obesity increased, in most regions, with significant variation in the magnitude of these changes across regions. We investigated how much change in mean body mass index (BMI) explains changes in the prevalence of underweight, obesity, and severe obesity in different regions using data from 2896 population-based studies with 187 million participants. Changes in the prevalence of underweight and total obesity, and to a lesser extent severe obesity, are largely driven by shifts in the distribution of BMI, with smaller contributions from changes in the shape of the distribution. In East and Southeast Asia and sub-Saharan Africa, the underweight tail of the BMI distribution was left behind as the distribution shifted. There is a need for policies that address all forms of malnutrition by making healthy foods accessible and affordable, while restricting unhealthy foods through fiscal and regulatory restrictions. © Copyright