EDITORIAL

The crops with comparative advantages in the markets are tropical perennials like sugar cane, palm, cacao, rubber and musaceas for export; with growth in permanent crop areas, due to, among other factors, their adaptation to environmental conditions and because they have a agribusiness chain. Other crops with advantages in free trade are fruits, vegetables and aromatioc and medicinal species due to their contribution to food security, value added to human nutrition, manual labor and alternative production in small farms and medium sized industry.

With the aim of disseminating scientific knowledge generated by science and technology programs, this issue of Agronomía Colombiana presents to the scientific and agricultural technology community advances in the area of plant breeding, genetic and molecular biology related to the development of transgenic potato lines with Tecia solanivora resistance, resistance in carnation populations to Fusarium oxysporum f. sp. dianthi, studies of genetic diversity of a Colombian bean collection and genetic comparison of commercial materials of oil palm; and studies on the enhancement of crop yields with knowledge of the genetic diversity used. In the search for and promotion of new production alternatives for the Colombian cold zone, the section on propagation and cultivation of tissues contains a manuscript of mass production of agraz seedlings (Vaccinium meridionale Swartz) from seeds germinated in vitro and seedlings hardened in organic substrates.

For the topic of crop protection, which saw a high number of contributions in this issue of Agronomía Colombiana, a valuable contribution to the knowledge of the pathogens that limit production is presented, as with the case of Rhizoctonia solani GA-3PT associated with stem blight and black scab of the potato, the invasive process of downy mildew (Peronospora sp.) in micropropagated rose plants, the generation of control methods for pathogens causing anthracnose which highly limits the production of the mango and tomato tree and the search for entomopathogenics to control lace bugs in the eggplant (Corythaica cyathicollis). This issue also contains a review of the current situation for the leprosis citrus virus (CiLV-C) and its vector Brevipalpus phoenicis (Geijskes).

For food processing and quality, studies analyzed the antioxidant activity and beta carotene content in improved guava (Psidium guajava L.) variety Palmira ICA I at two regional varieties and the content of cyanogenic glycoside amygdalin in almond seeds in relation to bitter taste with the genotype.

Furthermore, in the section on soil, fertilizer and water management, a study on the efficient application of inputs in crop fertilization assessed changes in the electrical conductivity, pH and nitrate, ammonium, sodium and chlorine levels in the solution drained from roses grown in substrates with recirculation and the effect of biological practices of phosphate solubilizing bacteria and compost applications on a crop of oil palm (Elaeis guineensis Jacq.). In this vein, this section ends with a contribution on the optimization of ventilation in greenhouses since design has been ignored in Colombia and in many cases poor microclimates have been generated for growing horticultural species.

In the area of economy and rural development, the articles contribute to a broad understanding of the agricultural sector with strategic aspects that were analyzed in a regional context and include a comparative analysis of production costs in the departments of Santander and Huila for Virginia tobacco and a model of business management and competitiveness for small and medium sized companies in the province of Tundama (Boyacá).

The editorial staff invites the scientific, academic and agricultural production communities to consult our journal Agronomía Colombiana, allowing us to maximize our national and international visibility; also, thanks to the editorial staff, translator, designer, and printer for this issue of the journal.

Gustavo A. Ligarreto M.
Editor