Revista de Investigación Agraria y Ambiental

13-26

Authors: Lucia Fabila Martínez, Salvador Adame Martínez & Rodolfo Serrato Cuevas

This study was developed out of the need to provide products and services intended for the field that meet the nutritional needs of plants without implicating environmental damage by means of chemical fertilizers and insecticides. The study assessed the fertilizer effect of two diatomaceous earth and a liquid fertilizer to corroborate empirical evidence of several producers who used a commercial product based on the study`s materials and achieved higher levels of performance in different crops. A sample of the experimental area was carried out before establishing the crop after its completion. Two commercial diatomaceous earth identified as 289 and 400 P produced by International Celite, were assessed at two concentrations 20 kg ha-1 and 40 kg ha-1 and 18 kg ha-1 and 36 kg ha-1 respectively, and a organic liquid fertilizer (FOL) at doses of 2 L ha-1 and 4 L ha-1 was considered as control soil sample taken before the application of treatments. The experimental design used in the field for the application of the treatments was randomized complete block (DBA) with 5 repetitions. The test plant was the corn hybrid HC8. The variables evaluated in the soil throudgh laboratory analysis were: physical properties of texture and bulk density (BD), and chemical pH, organic carbon (OC), organic matter (OM), electrical conductivity (EC), cation exchange capacity (CIC), nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg) and sodium (Na). The results were analyzed under a ANOVA and Tukey test for comparison of means for treatment, using the JMP statistical package. Laboratory results indicated that there were changes in the chemical characteristics of the soil between the control and treatments in the majority of the chemical characteristics analyzed (pH, CO, MO, N, P, K, Ca, Mg and Na). However statistically and under a statistical significance of 5%, differences were only observed in the properties of CO, MO, CE, N, K and Na.

37-42

Authors: Oscar Emerson Zúñiga Mosquera & Antonio Pereira Da Silva Neto

This research was conducted by seeking scientific information from the agronomy field, the revision of public policy documents for biodiesel production and, especially, the Biodiesel Development Poles Program. On-site visits were made in the municipalities of the valley of alto Pajeú, where the program is being conducted. The research considers the importance of raw materials and a territorial approach, in addition to examining the site as a basic unit for public policy.

55-65

Authors: Álvaro Vicente Araujo Guerra, Lina María Monsalve Castro & Andrés Luciano Quintero Tovar

This paper attempts to conceptualize the potential for some organic wastes to be used as energy sources. For example, whey produced by the dairy industry, which creates a serious environmental problem due to its effect on the physical and chemical structure of soils causing a decrease in crops yield and when disposed in water, reduces aquatic life by exhausting dissolved oxygen. Therefore, it is necessary to search for alternatives to lessen the impact caused by this type of agro-industrial waste. Such alternatives should also take advantage of the organic waste as an energy source that selected microorganisms can synthesize organic compounds within and subsequently obtain the microbial masses that constitute a major food source of high protein value. This alternative provides potential solutions to major issues such as human hunger, the lack of protein sources for animal feed and on the other hand, a reduction in environmental pollution.

97-116

Authors: Manuel Francisco Polanco Puerta & Mario Augusto García

Yacon (Smallanthus sonchifolius Poep. Z & Endl) H. Robinson is an Asteraceae native to the Andean region. It is a plant used by antiquated cultures as a refreshing fruit or low calorie food. Its roots are composed mostly of water (85-90%). 40 to 70% of its dry weight comes in the form of fructooligosaccharides (FOS), sugars with favorable effects on human health, and with a high antioxidant power, which is why it is considered medicinal; for the treatment of problems associated with diabetes. The high demand and price of the product in the domestic and international markets make this species a profitable option for farmers in the Eje Cafetero (Colombian Coffee)ecoregion, which has ideal agro-ecological conditions for its cultivation. However, there is neither precise information on the materials present in the region nor information on its productivity, making it difficult to propose the appropiate agronomic management to optimize its production. This research was conducted in five provinces of the Eje Cafetero ecoregion, collecting and morphologically characterizing the species. Subsequent morphoagronomic evaluations were performed using 18 quantitative descriptors, and eight qualitative ones, in addition to the molecular characterization with the RAMs technique using six initiators. The morphoagronomic characterization classified the ten collected biotypes into three groups. Molecular characterization distinguished four groups, which are closely related to the grouping according to the qualitative characteristics found. The paper concludes that the accessions of group one are the most appropriate for the production of tubers, those of group two for dualpurpose production and those of group three, for leaf production. The multiple correspondence analysis (MCA) indicates that within the germplasm there are important characters that can be used towards the selection of potential parents with desirable quality traits for breeders, farmers and consumers.

135-147

Authors: Fernando de Jesús Álvarez Ramírez, Guillermo Castaño Arcila, José Ferney Montes Moreno & Francis Liliana Valencia Trujillo

This paper investigates the conditions of the possibility that have contributed to the emergence of rural Agroecology schools and the Farmer Training Center in the municipality of Tulua, Valle del Cauca. Methodologically, it fits within the framework of the Historical Logical Cultural in three stages: the first related to the ECAS as Sustainable Human Rural Development which emphasizes the recovery of popular and ancient knowledge that facilitates an autonomous exercise, the second, a community strategy for the management and conservation of natural resources through the consolidation of an exercise related with the offices of the members of the ECAS and the third stage being based on the consolidation of work plans centered on sustainable endogenous development and the pursuit of well-being. It was found that the ECAS and Farmer Training Center are expressions of social construction where people interact through intracultural interscientific and transdisciplinary dialogue, stressing upon the seed savers as one of the offices within the ECAS that has a special significance especially now that we are witnessing a dictatorship under the aegis of transnational seed companies. The paper concludes that the ECAS and Farmer Training Center are the spaces par excellence where the exchange of knowledge and experiences materialize, with special reference to the seed savers and the importance of their work.

13-19

Authors: Luis Felipe Orozco, Katherin Castro-Ríos & Gonzalo Taborda Ocampo

Coffee pulp and mucilage are semi-liquid by-products involved in the generation of residual waters with a high concentration of organic matter and diverse species of microorganisms which negatively affect the efficiency of traditional treatment and require up to five months for total decontamination of these waters. This demands the testing of different treatment methods that can improve the efficiency of traditional processes. Electrocoagulation was tested with Fe/Al electrodes, 2.3 A and natural pH in a reduction in chemical oxygen demand and other microorganisms present in the coffee mucilage. The electrochemical process produced a maximum removal of 93% for coliform bacteria, molds and yeasts with a treatment time of 50 min. The reduction in chemical oxygen demand was 32% for the undiluted sample, 45% for the sample diluted to 50% (v/v), and 51% for sample diluted to 25% (v/v); indicating there is an increase in efficiency with a decrease in organic matter. The energy consumption was less than 0.083 kWh/m3 for the samples analyzed. This method is a viable alternative for the pre-treatment or reutilization of waters contaminated with coffee mucilage.

31-40

Authors: Carlos Iván Cardozo Conde & César Augusto Posada Tique

Ricinus communis L., commonly known as the castor- oil plant, is important for its use in biofuels production. With the objective of learning about its current status, in 40 villages influential to the oil complex of Caricare (municipality of Arauquita) and Caño Limón (municipality of Arauca) in Arauca, Colombia (where five years earlier the crop had been established), a collection of sexual seed was carried out between December 2011 and January 2012. The variables studied include passport data as a collection resource, local name, relief, and soil type among others. A Garmin map76CSx was used in order to identify the transects and record data such as geographic location and elevation. Simple descriptive statistics were used to identify the variables of greatest variation. Using the qualitative variables of greatest importance, a contingency table analysis with a significance level of 5%, a multiple correspondence analysis(MCA) and principal component analysis (PCA) were performed for quantitative and qualitative variables, in addition to a classification analysis through a similarity matrix. The castor-oil plant was found in 25% of the villages visited. 12 introductions were collected, four from Caricare and eight from Caño Limón. Although the environmental conditions were favorable for its cultivation, there are no castor-oil plant crops in the locations visited. The absence of grain commercialization and oil extraction equipment is the main limiting factor. A garden was established using collected materials for the purpose of research, breeding and propagation.

49-64

Authors: Carmen Mireya Lapo Pauta & Rafael Pérez García

This paper presents research completed with the intention of finding the most economical solution in the design of pressurized irrigation networks, while efficiently meet service delivery. A systematic methodology is proposed that combines two optimization techniques through a “hybrid method” in, which linear programming, nonlinear programming and genetic algorithms are fused. The overall formulations of the problem of optimal dimensioning consist of minimizing an objective function constituted through the asociated cost of the pipes that form the network. This methodology was implemented in three networks a fictitious irrigation and two irrigation networks (Tuncarta and Cariyacu) located in the cities of Loja and Chimborazo which yielded optimal design solutions. Finally different scenarios were simulated in both models to obtain an overview of the operation of the hydraulic variables

81-88

Authors: René Aguilar Anccota, Raquel Briggit García Raymundo, José Antonio Dulanto Bejarano & Edgar Abraham Maldonado Duque

The department of Piura is the principal banana-producing zone in Peru, sharing 87% of exportations.In this zone, one of the most important postharvest diseases is crown rot. The economic loses attributed to this disease are estimated to be between 25 and 30% of organic bananas exported. The objective of this study was to identify the causal agents associated with this disease. Samples taken refrigerated fruit from the areas of Querecotillo, Salitral and Mallares were taken and selected after the fact. Thielaviopsis paradoxa, Lasiodiplodia theobromae, Colletotrichum musae and Fusarium verticilloides. In order to demonstrate the pathogenicity of the isolated species, inoculations were given in the area of the crown of the fruit on healthy bananas. These fungi caused symptoms of infection in different proportions, concluding that crown rot is a disease with a complex etiology.

101-111

Authors: Walter Alfredo Salas-Zapata & Leonardo Alberto Ríos-Osorio

The transition toward sustainability is the set of changes and decisions a group of people make in order to resolve problems of sustainability. To address these problems a scientific trend has emerged called sustainability science, which has been considered to be a science inspired by the use of knowledge and must have characteristics such as transdisciplinarity, participation, social learning, coproduction of knowledge, as well as consider multiple perspectives and scales of problems and the uncertainty inherent to them. However, scientific research plays a particularly important role in the decision making processes. The chances of success greatly increase when permits interaction and communication between researchers and decision makers, or other actor. This paper analyzes how the characteristics in question contribute to the promotion of changes toward sustainability