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 application on the yield increase, ascorbic acid content and lifecycle to harvest. Adequate water increases the percentage of the marketable quality and amount of fruit juice, and the use of rootstocks does not significantly change the fruit quality. Ensuring a pollination of the flowers in cultivation is decisive for the fruit formation and its juice content. The species differ greatly in their quality, as purple passion fruit (Passiflora edulis f. edulis) is a fruit that develops the highest content of ascorbic acid, while sweet calabash (P. maliformis) forms the maximum amount of phenols and total antioxidant activity. The maturation and ripening of passion fruit is determined by the skin coloration, during which the Brix grades and the maturity index increase and the titratable acidity diminishes. Fruits harvested early in physiological maturity and with unripe peel color can be treated with ethylene in post-harvest, matching fruits that ripened in the plant. More research is needed in the improvement of the quality of the Passifloraceae. Giant granadilla (P. cuadrangularis) and sweet calabash have been studied less than banana passion fruit (P. tripartita var. mollissima), purple passion fruit, yellow passion fruit and sweet granadilla (P. ligularis). The last three species are the most exported fruits in the country.

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Los virus que afectan las plantas son de gran importancia en la producción agrícola de Colombia. Diferentes estudios indican que las pérdidas económicas causadas por estos problemas fitosanitarios, podrían evitarse con un mayor conocimiento sobre estos patógenos y mediante un sistema de manejo como guía. Los viveros, productores, comercializadores y consumidores, se beneficiarían de productos de calidad al controlar las fuentes de virus. Los acuerdos de libre comercio han dado lugar a una expansión de la producción agrícola y a la proliferación de cientos de viveros que no han sido objeto de inspección minuciosa por parte del estado. Este artículo presenta los principales virus que afectan dos importantes frutales exóticos de exportación para Colombia, los frutos de pasión (Passiflora sp.) y la uchuva (Physalis peruviana).  A su vez, esquematiza lo que sería un programa de producción y certificación de material vegetal sano para los viveros y  la creación de un programa nacional de certificación de material, dirigido por el Ministerio de Agricultura y Desarrollo Rural y el Instituto Colombiano Agropecuario (ICA); apoyado por las universidades con carreras agrícolas, centros de investigación y laboratorios fitosanitarios que proporcionarían un sistema de supervisión y control adecuados, para el material vegetal y esquemas de asistencia técnica oportuna para los agricultores. Esta iniciativa interinstitucional también apoyaría la implementación y el ajuste de las resoluciones fitosanitarias del ICA en semillas (R. 2046/2003), material de propagación en  frutales (R. 3180/2009) y la resolución recientemente aprobada para el transporte interno de material vegetal (R. 3973/2016). Los productores necesitan acceso a material vegetal sano, para proteger la seguridad alimentaria nacional y mantener una ventaja competitiva en el mercado.

Waterlogging stress is a limiting factor in the production of crops grown in localities with high rainfall frequency. Waterlogging causes a decrease in the availability of O2 in roots, which substantially affects the anatomy, morphology and metabolism of plants. Oxygen deficiency inhibits mitochondrial respiration, oxidation, and oxygenation processes, causing severe affection of plant metabolism. A test in greenhouse conditions was carried out in Tunja, Colombia, in order to evaluate the effect of waterlogging on the growth of cabbage plants (Brassica oleracea var. capitata). Some plants were waterlogged for 25 days and their physiological response was compared with plants maintained at field capacity. As consequence of waterlogging, leaf area, total dry weight, chlorophyll content, leaf area ratio, absolute growth rate and relative growth rate were reduced. In addition, necrotic plants exhibited a high percentage of necrosis in the leaves. As for the variables related to chlorophyll fluorescence, there was a decrease of 17,9, 50,0 and 36,0% in the Fv/Fm values, ΦPSII and qP, respectively. All of these results indicate low tolerance of cabbage plants to waterlogging.

Plant viruses may pose a threat to crops in Colombia. To evaluate the potential risk of yield losses due to plant virus infection, a literature analysis followed by a first field study was carried out focusing on purple passion fruit (Passiflora edulis Sims), cape gooseberry (Physalis peruviana L.), and ornamental rose (Rosa sp.), which are important Colombian exports. Over the past three years, plant material was collected from 21 farms in Cundinamarca and Boyacá, Colombia, two regions that are in close proximity to El Dorado International Airport, the country’s largest air freight terminal. Plants were visually inspected and subsequently tested by bioassay and serological methods. Overall, in the samples investigated by the two diagnostic methods, plant viruses were detected. Detected viruses belong to the genus Poty-, Tobamo-, Nepo-, Ilar-, and Tospovirus. The extent of the distribution and occurrence of these viruses in each crop has to be determined in a representative field study. Such a monitoring program could be supported by a standardized farmer interview. The development of suitable plant virus diagnostic and managements tools is the focus of a cooperation project between German and Colombian universities, the Colombian Agricultural Institute (ICA), the Colombian Corporation of Agricultural Investigation (AGROSAVIA) and the International Center for Tropical Agriculture (CIAT).

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