Gerhard Fischer

Universidad Nacional de Colombia | UNAL · Departamento de Agronomía (Bogotá)

Yellow pitahaya is a tropical fruit with economic potential due to its physicochemical, organoleptic and nutritional properties. Given the CAM (crassula acid metabolism) of pitahaya, it is necessary to study the stomatal aperture and acidic behaviour in the cladode and fruit in field and postharvest in order to understand the physiology, crop manag...

The aim of this review is to provide information on the conditions that facilitate the production of high-quality Myrtaceae fruits that are important in Colombia. Many fruits of the Myrtaceae family have very important nutritional, functional, and economic characteristics. In Colombia, commercial fruit trees of the Myrtaceae family include guava (P...

Commercially grown fruit crops in the high tropical Andes zones from 1,600 to 3,200 m a.s.l. are increasingly important in the world market, mainly because they are exotic fruits, and also because they are produced by hundreds of small growers. Photosynthesis is one of the most important physiological processes involved in the production and qualit...

The tropical highlands, which are less affected by global warming than lower areas, offer land suitable for the cultivation of fruit trees. These fruit species are mostly native to the Andes themselves, belonging to the families Solanaceae, Passifloraceae, Mirtaceae, Rosaceae, and Ericaceae. They are cultivated in the Colombian Andes, in areas with...

In the Colombian highlands, the use of native and/or improved varieties of vegetables, adapted to the elevation range and the adversities of climate change, are of great importance. To increase vegetable production, quality, and sustainability, new cultivation practices that are easy to implement have been proposed. These include enriching the spec...

Climate factors affect the phenological behavior of Japanese plum (Prunus salicina Lindl.) cultivation in tropical elevation. Thermal time is more precise than chronological time for the cultivation labor program and for the estimation of crop phenological events. The objective of this study was to determine the base temperature (Tb) and thermal ti...

Calcium (Ca) plays a crucial role as a nutrient influencing the ripening, post-harvest duration, and quality of fruits. Its impact on the cell wall and its function as a secondary messenger at the cellular level underscore its significance. While recently there has been an increase in studies examining the effects of Ca on fruit quality, there rema...

The goldenberry adapts well to altitudes between 1500 and 3000 m a.s.l., with optimum average temperatures in Colombia between 13°C and 16°C. 1500–2000 hours/year of direct sunshine promote the size, quality, and ripening of fruits. Light use efficiency is much higher in the reproductive stage. The roots and the basal vegetative stem are the larges...

The Japanese plum tree is of great importance in the productive development of Colombian fruit growers due to its nutritional contribution to human health, its great adaptability in the tropical highlands, and its good yields. This review presents the current investigative state of physiology of this plant and its management in tropical highlands,...

The cultivation of cape gooseberry in Colombia has increased in recent years, both in terms of export volume and production; however, yield has decreased by 19%. Therefore, it is necessary to evaluate major factors that affect fruit production and postharvest behavior such as irrigation and calcium fertilization. A design with three randomized bloc...

The adaptation of fruit species to higher elevations is generally related to climatic conditions, such as lower temperatures and partial pressure of gases and, importantly, higher solar radiation, especially ultraviolet (UV)-B, as elevation increases. Decreases in temperature, about 0.6–0.7°C per 100 m of tropical elevation, increase plant phenolog...

Drift from herbicides in fields adjacent to non-target crops,together with waterlogging can be detrimental to lettuce(Lactuca sativa L.). The objective of the study was to determinephysiological responses of lettuce plants to exposure to glypho-sate and waterlogging. Lettuce plants were subjected to treat-ments of combinations of foliar application...

The growth in urbanization and industrialization is causing an increase in environmental pollution in cities and their surrounding areas. Additionally, the growing urban population requires a greater volume of fresh vegetables. In nature, heavy metals (HM) are widely distributed; when they gradually enter the soil-plant-consumer continuum, they are...

The irrigation of crops represents 70% of the world’s water use. For crops grown in highaltitude tropical climates, due to the decrease in rainfall with increasing altitude, along with the effects of global warming, it is necessary to propose alternatives for sustainable fruit production with reduced water consumption. This study was carried out in...

Incidents of flooding in tropical and subtropical fruit trees have increased as a result of climate change. Because of flooding, the anaerobic conditions of the rhizosphere increase the conditions for phytotoxicity and infection by pathogenic fungi and bacteria. Due to oxygen depletion in waterlogged soils, growth, functions of the roots and of the...

Nutrient deficiency symptoms are widely used to determine the nutrient demands of a crop and to clarify nutritional disorders, especially when they are nutrient specific. Until now, a calcium (Ca), magnesium (Mg) and boron (B) deficiency experiment has not been carried out on feijoa, and diagnostic symptoms have not been described. For this reason,...

The increase in solar radiation and temperature as a result of climate change and variability has increased sunburn damage to fruits, which highly affects quality and yield in tropical and subtropical fruit plants. Solar injuries increase because of conditions with low relative humidity, fruits left uncovered by foliage, and plantations at higher a...

The impact of altitude on the different sugars and acids of the feijoa fruit is unknown. For that reason, the objective of this study was to evaluate the altitudinal effect on the content of organic acids (citric and malic) and sugars (glucose, fructose, and sucrose) during the development of feijoa fruits. The study was carried out in the towns of...

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-physiolog...

Due to global warming, the highlands of the tropics have become more important for planting fruit trees. The climate at high altitudes is mainly characterized by decreased temperatures and increased solar radiation. A systematic literature review using four bibliographic databases revealed 22 studies that determined fruit quality at two altitudes....

Introduction. Several diseases affect the Andean blackberry cultivation in Colombia, where anthracnose (Colletotrichum spp.) stands out for generating total losses. Objective. To estimate the doses of N, P, K, and Ca that allow greater tolerance to C. gloeosporioides strain 52 in Andean blackberry seedlings. Materials and methods. The experiment wa...

Champa (Campomanesia lineatifolia R. & P) is a fruit with an exquisite taste and pleasant aroma, with high commercial potential because its flavor and nutritional composition, but it is highly perishable, and various aspects of its physiology are still unknown. The objective was to study the behavior of champa fruit during postharvest. Fruit were c...

La uchuva, procedente de las zonas andinas de Suramérica, es un arbusto con una altura entre 1 y 1,5 m, formando frutos dentro de un cáliz cerrado. Con un peso entre 4 y 10 g parecen a un mini-tomate de color amarillo-anaranjado. Los frutos se destacan por sus altos niveles de beta-caroteno y ácido ascórbico, hierro y fósforo. En Colombia, en el añ...

Since the industrial revolution, anthropogenic activities have increased atmospheric CO2 concentration—one of the major causes of global warming—with a 600 to 700 ppm prediction by the end of this century. Orchards and vineyards are critical sustainable production systems that can minimize emissions and sequester carbon within the atmosphere. Infor...

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 u...

RESUMEN: La uchuva es un fruto de color amarillo-anaranjado que crece dentro de un cáliz cerrado, siendo, probablemente, procedente del Perú. Es una planta arbustiva que crece hasta una altura de 1,0-1,5 m. Los frutos redondos, normalmente entre 4 y 10 g, contienen concentraciones altas de ácido ascórbico, beta-caroteno, fósforo y hierro. En Colomb...

Dada la importancia y la potencialidad de algunas de las berries cultivadas (fresas, frambuesas, moras, zarzamoras, arándano, agraz y la uchuva, entre otras), la Sociedad Colombiana de Ciencias Hortícolas (SCCH) convocó para este año 2021, a un selecto grupo de especialistas de varios países productores de estos frutales, con el fin de elaborar est...

La Sociedad Colombiana de Ciencias Hortícolas (SCCH) convocó para este año 2021, a un selecto grupo de especialistas de varios países en estos temas, con el fin de elaborar esta obra que pretende dar a conocer el panorama actual de estas áreas del conocimiento, el escenario mundial de la horticultura (transcurridos 20 meses del inicio de la pandemi...

Plants often express deficiencies with visible abnormalities; however, it is necessary to obtain reliable information to make the proper diagnosis about the missing nutrients. Until now, research with this approach has not been carried out for crops such as feijoa (or pineapple guava). For this reason, the present investigation identified and descr...

The objective of this review was to report on advances in environmental , cultural, and physiological aspects of fleshy fruit cracking that have reduced or avoided this disorder, which affects many fruit species. Cracking is a physiological disorder that limits the production and quality of fleshy fruits because it affects the exocarp and mesocarp,...

El área cosechada de mora de Castilla en Colombia a finales de 2020 ascendió a 14.603 ha con una producción de 143.773 t y un rendimiento nacional de 7 t ha-1. En Colombia, este cultivo es la base de muchas unidades de agricultura familiar en la región cafetalera del país. Dicho sistema productivo está expuesto a diversos problemas fitosanitarios y...

Climate change, with its consequent increase in temperatures and precipitation, has significant impacts on soil surface horizons, affecting the establishment, development, and production of crops and food security and safety. Solar radiation influences the thermals of Earth's surface. Apart from radiation, the effects of soil temperature (STe) are...

The high Andean areas present ecophysiological conditions suitable for the cultivation of many fruit species, especially of the Solanaceae family. The objective of this review is to present important ecophysiological information on four fruit trees grown in cold climates: Cape gooseberry, tree tomato, lulo, and sweet cucumber o pear melon. The cape...

In order to seek management alternatives for anthracnose caused by the fungus Colletotrichum gloeosporioides in blackberry (Rubus glaucus Benth.), at the Tibaitatá Research Center of the Colombian Agricultural Research Corporation AGROSAVIA (formerly CORPOICA), an experiment was conducted to evaluate the effect of the application of the major eleme...

The development of Andean fruit crops is viewed as an important and healthy contribution to global food consumption but ecophysiological studies on these fruit trees are scarce. 96% of approximately 520 Passiflora L. species are distributed in the Americas, especially in Colombia and Brazil. Many of these species originated on the edges of humid fo...

Guava, due to its ability to grow in tropical and subtropical climates, has been introduced to some 60 low-latitude countries. It adapts to temperature ranges between 15 and 30°C. Outside this range, the effect of lower or higher temperatures reduces, in the first place, fruit set, while night temperatures of 5 to 7°C stop growth. Additionally, low...

La demanda de frutas exóticas, entre ellas la uchuva, se ha venido incrementando debido a sus excelentes propiedades nutricionales y sus altos contenidos de vitaminas A, B y C y de minerales como el calcio, el hierro y el fósforo, ideales para fortalecer el sistema inmunitario. Los frutos de la uchuva tienden a rajarse, por lo que debe suministrárs...

In order to estimate the base temperature (Bt) of growth through the appearance of leaves and calculate the phyllochron for kikuyu grass, three plots were established on three farms in the Provincia of Ubaté (Cundinamarca, Colombia) located at different altitudes (2560, 2640, 3143 m. a. s. l.). Measurements were made in four cycles in a period of e...

Climatic alterations affect the physiology, growth and production of the feijoa, a native plant to the higher zone between Brazil, Uruguay, Paraguay and Argentina. In Colombia, optimal growth temperatures are between 13 and 21°C (16°C). Very high temperatures (>32°C) affect pollination and fruit set, but low temperatures down to -4°C in adult plant...

This study used greenhouse conditions to determine the hyperspectral responses of cape gooseberry (Physalis peruviana L.) plants inoculated with different Fusarium oxysporum f. sp. physali densities because the causal agent of vascular wilt generates great economic losses for farmers. A completely randomized design with four replicates was establis...

La feijoa es un frutal con gran potencial para el consumo humano, que se cultiva entre los 1800 y 2700 msnm en Colombia. Está bien adaptada a temperaturas bajas, resistiendo por corto tiempo temperaturas <0 °C, mientras que temperaturas >32 °C afectan su floración. La temperatura base para botón floral a antesis es 2,89 °C, de antesis a cuajamiento...

To determine the optimum harvest time of kikuyu grass (Cenchrus clandestinus (Hochst. ex Chiov.) Morrone), according to the number of leaves per tiller and nitrogen fertilization level, an experiment was carried out under greenhouse conditions using a 4×4 factorial design. The factors were the number of leaves per tiller (3, 4, 5, 6 leaves) and lev...

Se describen las características morfológicas, las condiciones de clima y suelo para el cultivo comercial de la curuba, las variedades y cultivares, el establecimiento y manejo del cultivo, las principales enfermedades e insectos-plagas, la cosecha y poscosecha, así mismo la comercialización y el valor agregado.

In a literature review of the ecophysiology of the cape gooseberry (Physalis peruviana L.) it was found that in Colombia this typical Andean plant adapts to a wide altitudinal range of the tropical cold climate, between 1,800 and 2,800 m a.s.l., with optimal medium temperatures between 13 and 16°C and base (minimum) temperatures for stem and fruit...

The curuba (Passiflora tripartita var. mollissima) is an important Andean fruit in bioprospecting industries because of its pleasant taste and aroma, antioxidant potential and sedative action. The objective of this study was to evaluate the development of curuba plants and the physicochemical characteristics of fruits under two environmental tropic...

To determine whether the management of irrigation and nutrition in cape gooseberry crops with calcium to reduce the cracking of fruits affects the water potential of the plants, the present study was carried out using a randomized block design with 12 treatments in a 4×3 factorial arrangement. The blocks were the irrigation frequencies (4, 9 and 14...

Climate change has resulted in an increasing frequency of the phenomenon “La Niña,” generating prolonged periods of waterlogging and low light. The objective of the present study was to evaluate the effects of two abiotic stresses: shading (65%) and waterlogging, and their interaction on fluorescence parameters of chlorophyll a in lulo (Solanum qui...

Este libro, editado por Luz Marina Melgarejo, se puede descargar gratis y completamente a través del link: "Gulupa (Passiflora edulis), curuba (Passiflora tripartita), aguacate (Persea americana) y tomate de árbol (Solanum betaceum) Innovaciones". Su contenido es: I. Aspectos en germinación, morfoagronomía, fenología, nutrición mineral, calidad de...

Este capítulo es parte del libro "Gulupa (Passiflora edulis), curuba (Passiflora tripartita), aguacate (Persea americana) y tomate de árbol (Solanum betaceum) Innovaciones" , editado por Luz Marina Melgarejo, que se puede descargar gratis y completamente a través del link: "Gulupa (Passiflora edulis), curuba (Passiflora tripartita), aguacate (Perse...

El libro va dirigido al sector agrícola, a cultivadores, al sector académico-investigativo, así como a personas interesadas en avances de la investigación en gulupa, curuba, aguacate cv. Hass y tomate de árbol, para su tecnificación y manejo. Los resultados se presentan en dos grandes temáticas: la primera, relacionada con aspectos de la germinació...

To propose alternatives for management Anthracnose (Colletotrichum gloeosporioides) in blackberry cultivation, an experiment was performed to estimate the effect of nitrogen, phosphorus, potassium and calcium on C. gloeosporioides strain 52 infections. A randomized complete block design was used with a treatment arrangement corresponding to an orth...

Because of the high susceptibility in strawberry fruits to attacks from pests and diseases, a large amount of pesticides is applied during the crop cycle and harvest period. The improper use of these substances can generate residues in agricultural products that pose a risk to human health. The objective of this study was to determine and compare p...

Las condiciones climáticas de cultivo, que definen las propiedades o atributos de los frutos de feijoa en la recolección, determinan también el comportamiento de los mismos durante la postcosecha. En este estudio se evaluó el efecto de las condiciones climáticas de cultivo en algunos atributos de calidad de la fruta en el momento de la cosecha, así...

Colombia is the country with the greatest genetic diversity in passion fruit species, some of which are cultivated on an area of approximately 13,673 ha. Each variety must be planted at a suitable altitude under optimal conditions to obtain the best quality. Regarding plant nutrition, potassium has the greatest influence due to the effect of its ap...

La gulupa es un frutal nativo producido en Colombia y exportado a diferentes mercados internacionales. Los principales problemas que afectan la producción del cultivo están relacionados con la floración y fructificación, debido a limitaciones nutricionales, como la deficiencia de boro (B). La presente investigación tuvo como objetivo, evaluar el ef...

The quality of pineapple guava fruits during post-harvest storage depends directly on their quality at harvest and is influenced by climatic conditions during growth. The aim of this study was to determine the influence of climatic conditions on certain parameters of fruit quality during post-harvest storage. Twenty trees were tagged in two locatio...

Demand for conservation and recycling of water has increased significantly. Therefore irrigation water used for horticultural or agricultural purposes needs to be treated before being reused to eradicate plant pathogens and thereby reducing the risk of pathogen dispersal and losses due to disease. The economically important fungal plant pathogens F...

El mercado de la fresa en el departamento de Cundinamarca (Colombia) se rige principalmente por el tamaño del fruto, sin valorar su estado de maduración ni su calidad nutricional, desaprovechando su potencial organoléptico y nutritivo. Por esta razón, se determinaron las diferencias fisicoquímicas en frutos de siete variedades de fresa: Albión, Dul...

In Colombia, climate change causes an increased incidence of waterlogging and flooding in many agricultural areas, affecting crops, such as the cape gooseberry, which is very prone to Fusarium oxysporum. In a greenhouse, 2-month-old seed propagated cape gooseberry plants, grown in 2-L pots filled with horticultural soil+sand (70:30 vol%) that was p...

La ecofisiología estudia los efectos de las condiciones ambientales sobre la fisiología de las plantas, resultados que son de gran importancia en tiempos del cambio climático. El clima predominante en las zonas de origen de los frutales solanáceas da las bases para su adaptación a nuevos sitios de cultivo. Siendo el aumento de la temperatura por el...

La uva camarona o chaquilulo (Macleania rupestris) es una especie de la familia Ericaceae, que crece de manera natural en regiones de clima frío (2.200 a 3.500 msnm). Esta especie se encuentra presente en la mayoría de los departamentos de la zona andina, son consideradas promisorias y con un gran potencial de consumo, por sus excelentes propiedade...

El motilón (Hyeronima macrocarpa) es una especie de la familia Euphorbiaceae que crece de manera natural en los páramos del departamento de Nariño y cuyos frutos son cosechados por los campesinos para su venta en fresco en el mercado local. Sin embargo, resultados de investigaciones recientes arrojan que es una especie con gran potencial en su uso...

The post-harvest quality of pineapple guava fruit is determined by the storage and prevailing weather conditions during growth and development. This study proposes a model for post-harvest fruit quality according to the storage and weather conditions in the pineapple guava growing region. Physiologically ripe fruit were collected during two harvest...

El estado nutricional de las plantas es fundamental para asegurar una producción de calidad y de alta rentabilidad. Las deficiencias pueden ocasionar pérdida en el rendimiento y disminución de la calidad en los frutales como la feijoa. Las plantas a menudo expresan las deficiencias con anormalidades visibles, sin embargo, es necesario tener informa...

Durante el 2014 en la provincia de Pamplona, Colombia, se realizó un estudio sobre la variedad de duraznero Jarillo, con el fin de clasificar una serie de variables morfométricas distribuidos en tres fincas de diferenter al-titud (Pamplona, 2.170 msnm; Chitagá, 1.870 msnm y Pamplonita, 1.670 msnm). Para el muestreo de árboles se utilizó el hipercub...

The effect of the amount of fertilization applied to the corn variety ‘ICA V-156’ (white grain) was calibrated and validated with the simulator AquaCrop in Cerete (Cordoba, Colombia) at an altitude of 20 m. The fertilization level determined factors related to biomass production, the harvest index, yield and water use, and potential evapotranspirat...

La cholupa (Passiflora maliformis) es una fruta exotica, originaria del departamento de Huila (Colombia), presenta grandes cualidades organolépticas, es un frutal promisorio para comercialización nacional y su posible exportación, por tanto se hace importante la evaluación de su comportamiento poscosecha con miras al entendimiento de su comportamie...

Los factores que influyen en la calidad de las frutas pasifloráceas comerciales en el País (maracuyá, gulupa, granadilla, curuba, badea y cholupa) dependen de las condiciones climáticas y del manejo del cultivo, además de las condiciones en poscosecha que son determinadas por el genotipo (variedad) de la planta. Las exigencias a los factores climát...

La curuba es un frutal andino con alto potencial de exportación dadas sus propiedades organolépticas y bioquímicas; sin embargo, se desconocen aspectos de la fisiología del cultivo en función del ambiente físico, que está en constante cambio. Esta investigación tuvo el objetivo de evaluar aspectos de la fotosíntesis, el uso eficiente del agua y el...

Weather conditions influence the quality parameters of pineapple guava fruit during growth and development. The aim of this study was to propose a model of pre-harvest fruit quality as a function of weather conditions in the cultivation area. Twenty trees were flagged per farm in 2 localities of the Department of Cundinamarca, Colombia: Tenjo (2,58...

The growth of the pineapple guava fruit is primarily stimulated by temperature but is also influenced by other climactic factors, such as altitude. The goal of this study was to develop a growth model for the pineapple guava fruit as a function of thermal time (GDD, growing-degree day) and altitude (H) of the production area. Twenty trees per farm...

Los efectos de los factores climáticos, acentuados por el cambio climático, no han sido estudiados suficientemente en los frutos. El calentamiento global, acompañado de un aumento de la intensidad lumínica y la concentración de CO2, afectan la calidad y longevidad de los frutos. Dentro de un rango de temperatura óptima de cultivo, la alta radiación...

The increased concentration of carbon dioxide (CO 2) and other greenhouse effect gases has led to global warming, which has resulted in climate change, increased levels of ultraviolet (UV) radiation and changes in the hydrological cycle, affecting the growth, development, production and quality of fruit crops, which undoubtedly will be difficult to...

The increased concentration of carbon dioxide (CO2) and other greenhouse effect gases has led to global warming, which has resulted in climate change, increased levels of ultraviolet (UV) radiation and changes in the hydrological cycle, affecting the growth, development, production and quality of fruit crops, which undoubtedly will be difficult to...