Efecto del riego y la nutrición con calcio en la producción, rajado y calidad poscosecha de la uchuva (Physalis peruviana L.) En invernadero

La uchuva es la fruta exótica más importante para Colombia. Los frutos de uchuva presentan problemas de rajado lo cual disminuye su calidad poscosecha. Estos problemas están asociados a deficiencias de calcio y un manejo inadecuado del riego. Se empleó un diseño en bloques al azar con 12 tratamientos en arreglo factorial de 4x3. Los bloques fueron las frecuencias de riego (4, 9 y 14 días). El primer factor fue la lámina de riego (0,7; 1,0; 1,3 y 1,6 de la evaporación del tanque clase A) y el segundo la dosis de calcio (0, 50 y 100 kg ha-1), lo que representó 36 unidades experimentales. Se transplantó en materas de 20 L usando turba rubia como sustrato. El coeficiente de riego que presentó los frutos con mayor masa fue el de 1,0 sin ser significativo. Las aplicaciones de menor cantidad de agua aumentaron el contenido de sólidos solubles totales (SST), la acidez total titulable (ATT), el pH y la firmeza de los frutos. Los frutos de las plantas que recibieron mayor aplicación de calcio presentaron menor cantidad de SST, menor pérdida de peso en el tiempo y mayor firmeza y pH, este último sin diferencias significativas. La frecuencia de riego de 14 días presentó los mayores valores de SST. La vida poscosecha de los frutos de uchuva se vió aumentada al aplicar 100 kg ha-1 de Calcio con un coeficiente de riego de 1,0 y una frecuencia de riego de 4 días, no obstante los frutos son menos dulces. Las concentraciones de calcio no afectaron los contenidos de ácido ascórbico ni carotenoides totales. La lámina de riego más alta (1,3) aumentó el contenido de carotenoides totales en los frutos. Las plantas con frecuencia de riego de 14 días desarrollaron frutos con mayor cantidad de ácido ascórbico tanto en frutos sanos como rajados. Los frutos sanos presentaron mayor contenido de carotenoides totales y ácido ascórbico comparado con los rajados.Abstract. The cape gooseberry is the more promising exotic fruit exported from Colombia. Fruits of this species are susceptible to cracking, a disorder which is influenced by the calcium applications and irrigation management which can affect the nutraceutical properties of this fruit. There, the total carotenoids and ascorbic acid contents in fruits of cape gooseberry Colombian ecotype were evaluated. Plants were irrigated in different frequencies (each 4, 9 and 14 days) and water levels (0.7, 0.9, 1.1, and 1.3 of evaporation of class A tank), as well as calcium doses (0, 50 and 100 kg ha-1). The experimental design was in randomized blocks (irrigation frequency) with 12 treatments (the combination of the water levels and the calcium doses). Plants were planted in 20 L plastic pots filled with peat moss and placed at a distance of 1.5 m between plants and 2 m between rows. When the plant was 11 months old, the fruits were harvested at state 3 of ripeness according to Norma Técnica Colombiana 4580. A factorial analysis of variance was used and the Tukey's range test at 5% was applied to compare means. The calcium concentrations did not affect the contents of ascorbic acid and total carotenoids. The highest irrigation coefficient (1.3) increased fruit total carotenoids content, while the lowest irrigation coefficient (0.7) had the lower carotenoid values. Plants with irrigation frequency of 14 days developed fruits with highest ascorbic acid content, in both, healthy and cracked fruits. Healthy fruits had higher total carotenoids and ascorbic acid contents compared to cracked fruits. The cracked fruits showed a stronger oxidation process, which increased the dehidroascorbate and decreased the ascorbic acid concentration.Doctorad

Aspectos de la fisiología y el cultivo del lulo (Solanum quitoense LAM.) en Colombia: una revisión

Contextualization: lulo is a promising fruit of high demand in the markets due to its excellent organoleptic properties, as well as an important source of vitamins and minerals.  Knowledge gap: in the last ten years, multiple investigations have been carried out about  the ecophysiology of the lulo plant, without  a previous literature review of this.  Purpose: collect general aspects of the lulo crop, including the main agronomic requirements and ecophysiological aspects for sustainable production.  Methodology: the research was based on a methodical and orderly review of the most relevant studies published in different databases.  Results and conclusions: lulo plants grows between 1,900 and 2,200 m. a. s. l. in Colombia with temperatures of 15 to 24 °C. It requires between 1,500 to 2,500 mm of precipitation per year. It appears like a short-day plant, which exhibits its best development in shady places with relative humidity close to 80 %. The most efficient pollination method is carried out by bumblebees (Bombus terrestris and Bombus sp.) through vibrations. The net photosynthesis of the lulo plants varies from 5.52 to 34.03 μmol CO2 m-2 s-1 at 398 and 460 days after transplanting, while the maximum efficiency of photosystem II (FV/Fm) in the lulo crop oscillates between 0.55 and 0.65 for plants without and with foliar nitrogen application. The values ​​of a, b, and total chlorophyll, for lulo plants, are higher in plants in the transplant stage than in production, due to the reduced photosynthetic area. High concentrations of nitrogen (N) (greater than 110 mg L-1) lead to better yield and a larger leaf area. The lulo plant begins its production between eight and 12 months after being transplanted and average yields of 8.5 t ha-1  have been reported. The development and growth of lulo fruits have a simple sigmoid logistic model. The lulo fruits  in harvest time can reach up to 209 g, with firmness of 58 N and values ​​of 13,6 °Brix and 56.2, 10.8 and 46.8 for the luminosity (L*), chroma a* and chorma b* color parameters, respectively.Contextualización: el lulo es un fruto promisorio de alta demanda en los mercados, debido a sus excelentes propiedades organolépticas, además de ser fuente importante de vitaminas y minerales.  Vacío de conocimiento: en los últimos diez años se han desarrollado múltiples investigaciones sobre la ecofisiología de la planta de lulo, sin que exista una  revisión de literatura de este.  Propósito del estudio: recopilar aspectos generales del cultivo, incluyendo los principales requerimientos agronómicos y aspectos ecofisiológicos para una producción sustentable.  Metodología: la investigación se basó en una revisión metódica y ordenada de los estudios más relevantes publicados en diferentes bases de datos.  Resultados y conclusiones: el cultivo de lulo se cultiva entre los 1900 y 2200 msnm en Colombia, con temperaturas de 15 a 24 °C. Requiere entre 1.500 a 2.500 mm de precipitación al año. Se asemeja a una planta de días cortos, que exhibe su mejor desarrollo en sitios sombreados con humedades relativas cercanas al 80 %. El método más eficiente de polinización es el realizado por abejorros (Bombus terrestris y Bombus sp.) por medio de vibraciones. La fotosíntesis neta del cultivo de lulo varia de 5,52 a 34,03 μmol CO2 m-2 s-1 a los 398 y 460 días después de transplante; mientras que la eficiencia máxima del fotosistema II (Fv/Fm) en el cultivo oscila entre 0,55 y 0,65, para plantas sin y con aplicación de nitrógeno foliar.  Los valores de clorofila (a, b y total) para plantas de lulo son mayores en plantas en etapa de trasplante que en producción, debido a la reducida área fotosintética. Las concentraciones de nitrógeno mayores a 110 mg L-1 generan mejor rendimiento y mayor área foliar. La planta de lulo comienza la producción entre los ocho y 12 meses después ser trasplantada y produce rendimientos promedio de 8,5 t ha-1. El desarrollo y crecimiento de los frutos de lulo tiene un comportamiento que se ajusta a un modelo logístico sigmoide simple. Los frutos de lulo en la cosecha pueden llegar a alcanzar hasta 209 g con una firmeza de 58 N y valores de 13.6 °Brix y 56,2, 10,8 y 46,8 para los parámetros de color luminosidad (L*), cromaticidad a* y cromaticidad b*, respectivamente.O Lulo é uma fruta de grande procura nos mercados devido às suas excelentes propriedades organolépticas, para além de ser uma importante fonte de vitaminas e minerais. É cultivada entre 1.900 e 2.200 m a.s.l. na Colômbia, em uma faixa de temperatura entre 15 e 24 ° C, com uma temperatura base de 9,6 ° C para o crescimento do comprimento do caule. Requer entre 1.500 a 2.500 mm de precipitação por ano. Apresenta-se como uma planta de dia curto, que apresenta seu melhor desenvolvimento em locais sombreados com umidade relativa próxima a 80%. O método de polinização mais eficiente é realizado por abelhas (Bombus terrestris) por meio de vibrações. A fotossíntese líquida da cultura do lulo varia de 5,52 a 34,03 mmol CO2 m-2 s-1 aos 398 e 460 dias após o transplante, enquanto a eficiência fotossintética do fotossistema II na cultura do lulo oscila entre 0, 55 e 0,65 para as plantas sem e com aplicação foliar de nitrogênio. Os valores de clorofila a, clorofila be clorofila total para plantas de lulo são maiores nas plantas em fase de transplante do que em produção, o que é atribuído ao fato de as plantas na fase de transplante apresentarem área fotossintética reduzida com altas concentrações de clorofila. Altas concentrações de N (maiores que 110 mg L-1) proporcionam melhor produtividade e maior área foliar. A planta de lulo inicia a produção entre oito e 12 meses após o transplantio e apresenta rendimentos médios de 8,5 t ha-1. O desenvolvimento e crescimento dos frutos de lulo tem um comportamento que obedece a um modelo logístico sigmóide simples. Os frutos lulo na colheita podem atingir até 209 g com firmeza de 58 N e valores de 13,6 ° Brix e 56,2, 10,8 e 46,8 para os parâmetros de cor L *, a * eb *, respectivamente

Performance of the ‘Anna’ apple (Malus domestica Borkh.) in Tropical Highlands: A review

The 'Anna' apple is a variety of low requirements of winter chill (250 to 300 chilling hours ≤7.2°C). This apple has essential health benefits and remarkable adaptive potential in tropical and subtropical areas affected by climate change. Thus, this review presents the significance of the 'Anna' apple cultivation, the phenological and eco-physiological modifications, and the current state of agronomic management when continuous crops are managed in tropical highlands. The production of this apple in tropical highlands has outstanding potential to obtain cyclical or continuous harvests (two harvests per year) in certain areas with specific environmental conditions, implementing a particular management system. In plantations, it is crucial to carry out some agronomic practices during the reproductive phenology so that the apple tree does not enter into an endodormancy. These are water stress - defoliation – tie-down branches, and the application of dormancy-breaking agents (flower-inducing compounds). In Colombia, ‘Anna’ variety was introduced in 1985 and is grown in areas with temperatures between 14 and 20°C, altitudes between 1700 and 2800 meters above sea level (m a.s.l.), with bimodal and monomodal rain regimes, and solar brightness between 800 and 2000 hours a year. The harvest is between 100 to 120 days after anthesis, with firmness values of 38.38N, a soluble solids content of 8.58°Brix, and total titratable acidity of 0.7% of the fruit. This documentation indicates a good production with great potential in terms of growth and development, earliness, and quality of the 'Anna' apple tree in Colombian highlands

Aplicación de un fertilizante enriquecido con silicio y materia orgánica en arroz (oryza sativa l.) cultivado en ibagué y el guamo (tolima, colombia).

Este trabajo tuvo como objetivo evaluar el efecto de diferentes dosis y épocas de aplicación de un suplemento fertilizante enriquecido con silicio, materia orgánica y elementos menores en el cultivo de arroz variedad Fedearroz 50. El diseño experimental fue completamente al azar con factorial de 2 dosis (20 y 40 kg•ha-1) y 5 combinaciones de época y dosis de aplicación (100% Presiembra, 50% Presiembra + 50% 1ª abonada, 100% a la 1a abonada, 50% Presiembra + 50% 2ª abonada, 100% a la 2a abonada) comparados contra un testigo comercial (40 kg de SiO2) y un testigo tradicional de la zona. Las aplicaciones en segunda abonada del fertilizante generaron un incremento en el número de panículas. Se encontró que un mayor número de panículas correlaciona con un menor número de espiguillas llenas y un mayor porcentaje de vaneamiento, aunque este se vió disminuido con aplicaciones tempranas del fertilizante y factores climáticos. En la localidad de El Guamo la dosis de fertilizante más adecuada fue de 20 kg en primer abonada con rendimientos de 6906 kg•ha-1de arroz paddy, mientras que en Ibagué con 40 kg en segunda abonada se obtuvieron rendimientos de 9270 kg•ha-1. El modelo matemático sugiere que aplicaciones de 66,9 kg•ha-1 del fertilizante para la localidad de Ibagué incrementaran la producción de arroz a 8876 kg•ha-1en promedio

Effect of calcium chloride and refrigeration on the quality and organoleptic characteristics of cape gooseberry (Physalis peruviana L.)

The gooseberry is one of the exotic fruit species most important in Colombia. Calcium has been shown to be important for quality maintenance in fruits and vegetables, as it prevents a number of physiological disorders reinforce the cell walls and stabilize cellular membranes. With the aim to increase the fruit calcium concentration, a completely randomized design with four treatments was performed: a control and three applications of CaCl2 (0.5%, 1% and 2%), with four replicates, for a total of 16 experimental units (EU). The fruit was collected at maturity stage 6 according to the standard Icontec NTC 4580, completely healthy and homogeneous. The fruit was subsequently stored at 21 ± 1 ° C (RH 45%). The application of calcium in the gooseberry fruits decreased mass loss, firmness and ATT. Calcium treated fruit showed an increase in SST. In contrast, the treatments did not affect color. The doses of CaCl2 tested delayed ripening and prevented fruit deterioration

Study of the spatial variability of moisture and compaction in soils with different plant covers

Soil is a dynamic system, with physical, chemical and biological properties that have high spatial variability, making necessary to use innovative methodologies to study this variability. The aim of this study was to determine the spatial variability of moisture and compaction in soils with different plant covers. The study was conducted in the department of Boyaca (Colombia), municipality of Sogamoso, Ombachita District. A total of 95 sampling points were measured as a rigid network in an area of 34.18 ha, which were georeferenced and aken as representative for the plant cover in the sampling area. The values of penetration resistance (PR) found in the soil ranged from 0.717 to 1.385 MPa, so that, as the depth increased, the PR increased, while the volumetric moisture presented an inversely proportional behavior for depth. The cover that prevailed in the study area was a mosaic of pastures and crops (MPC), at 30.1%. The moisture values were lower in the area planted with eucalyptus. The PR showed greater spatial dependence at a greater depth, while the moisture presented a moderate dependence at different depths

Effect of different water levels on the growth and development of bulb onion (Allium cepa L.)

1 recurso en línea (páginas 359-367) : ilustraciones color.Debido al sistema radicular superficial, la cebolla de bulbo requiere de un suministro de riego en el momento y con la intensidad adecuada para favorecer la absorción de agua y nutrientes y obtener altos rendimientos. Se evaluó el efecto de diferentes láminas de riego en el crecimiento y desarrollo de cebolla de bulbo en un suelo franco arenoso y con un sistema de riego por aspersión. Se usó un diseño experimental completamente al azar con cuatro tratamientos (coeficientes de cultivo de 0,8; 1,0; 1,2 y 1,4 de la evaporación (Ev)), cada uno con 16 repeticiones, para un total de 64 unidades experimentales, donde cada unidad experimental correspondió a una parcela de 1 m2. El coeficiente de 1,2 (43 L por planta por ciclo) presentó los mayores promedios en masa seca total y masa seca del bulbo con diferencias significativas en relación al coeficiente de 0,8, pero sin diferencias con la aplicación de 1,0 y 1,4 de la Ev. Además, en masa seca de raíz el tratamiento de 1,2 Ev presentó el mayor promedio. En el crecimiento general no hubo diferencias significativas los primeros 70 días después del trasplante, pero luego de este tiempo se presentaron diferencias estadísticas y la aplicación de 1,2 de la Ev presentó la mayor acumulación de masa seca.Because of the shallow root system of the onion plant, it requires irrigation at the proper time and intensity in order to promote the absorption of water and nutrients to obtain a high yield. We evaluated the irrigation rate effect on onion growth and development in a sandy loam soil with a sprinkler irrigation system. The experiment design was completely randomized with four treatments (evaporation coefficients of 0.8, 1.0, 1.2 and 1.4 of (Ev)), each with 16 repetitions, for 64 experiment units; each experiment unit was a 1 m2 plot. The 1.2 coefficient (43 L per plant per cycle) showed the highest total dry mass and dry mass of the bulb with significant differences from the 0.8 coefficient, but no differences with the application of the 1 and 1.4 Ev. Furthermore, the 1.2 Ev treatment showed the highest root dry mass. There was no significant difference between the treatments during the first 70 days after transplant, but after this time, there was a statistically difference and the 1.2 Ev showed the highest dry matter accumulation.Bibliografía y webgrafía: páginas 366-367

Joint Observation of the Galactic Center with MAGIC and CTA-LST-1

MAGIC is a system of two Imaging Atmospheric Cherenkov Telescopes (IACTs), designed to detect very-high-energy gamma rays, and is operating in stereoscopic mode since 2009 at the Observatorio del Roque de Los Muchachos in La Palma, Spain. In 2018, the prototype IACT of the Large-Sized Telescope (LST-1) for the Cherenkov Telescope Array, a next-generation ground-based gamma-ray observatory, was inaugurated at the same site, at a distance of approximately 100 meters from the MAGIC telescopes. Using joint observations between MAGIC and LST-1, we developed a dedicated analysis pipeline and established the threefold telescope system via software, achieving the highest sensitivity in the northern hemisphere. Based on this enhanced performance, MAGIC and LST-1 have been jointly and regularly observing the Galactic Center, a region of paramount importance and complexity for IACTs. In particular, the gamma-ray emission from the dynamical center of the Milky Way is under debate. Although previous measurements suggested that a supermassive black hole Sagittarius A* plays a primary role, its radiation mechanism remains unclear, mainly due to limited angular resolution and sensitivity. The enhanced sensitivity in our novel approach is thus expected to provide new insights into the question. We here present the current status of the data analysis for the Galactic Center joint MAGIC and LST-1 observations

Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis