Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

Introduction. Biol and deficit irrigation reduce the use of synthetic fertilizers and optimize water use, respectively. Objective. To analyze the impact of a leaf litter-based biol and deficit irrigation on lettuce cultivation (Lactuca sativa L.). Materials and methods. A randomized complete block design with a 2 × 3 factorial arrangement was used. The evaluated treatments were T1 (without biol + 100 % of ETc), T2 (without biol + 75 % of ETc), T3 (without biol + 50 % of ETc), T4 (with biol + 100 % of ETc), T5 (with biol + 75 % of ETc), and T6 (with biol + 50 % of ETc). The evaluated variables included physicochemical characterization of the biol, agronomic performance of the crop (root diameter, root length, leaf length, number of leaves, total weight, commercial weight, yield, and dry matter), and water use efficiency. Results. The biol showed a pH of 5.6, electrical conductivity of 6.92 dS/m, and a temperature of 22.5 °C, as well as high levels of essential nutrients such as nitrogen, potassium, calcium, and iron. Regarding heavy metals such as cadmium and lead, concentrations remained within internationally acceptable standards. Agronomically, significant differences were observed in plant height, root diameter, leaf length, number of leaves, and total weight between treatment T4 (with biol + 100 % of ETc) and T3 (without biol + 50 % of ETc). However, no statistical differences were found in the remaining variables. Conclusions. Biol improved the cultivation of Lactuca sativa L. T4 showed the highest yield, while T6 reached 21.04 kg/m³, suggesting more efficient water use under deficit irrigation.

Introduction. Of the five cultivated pepper species, Capsicum annuum L. is the most important worldwide, due to its high demand in the food, medical, and cosmetic industries, among others. Mexico has the greatest diversity of cultivated types, including jalapeño, guajillo, ancho, serrano, and habanero. However, some farmers grow native materials that should be studied and preserved, such as mulato and chilaca. In certain cases, like chilaca, there are no improved commercial cultivars, so producers depend on the seed they produce. Objective. To morphologically characterize advanced lines of different C. annuum types from central Mexico. Materials and methods. The study was conducted during the spring-summer cycles of 2022 and 2023, at the Bajío Experimental Station, located in Celaya, Guanajuato, Mexico. In 32 advanced lines of eight C. annuum types, 42 traits were evaluated based on the guidelines of the International Union for the Protection of New Varieties of Plants and the International Plant Genetic Resources Institute guide. The data obtained were analyzed using descriptive statistics and subjected to cluster and correspondence analysis. Results. Morphological variation showed that fifteen plant, leaf, and fruit traits were crucial to differentiating pepper types and lines. Based on similar traits, the cluster analysis grouped them into five clusters. Groups I and III included three pepper types, and six traits presented the highest positive eigenvectors. Conclusions. The observed diversity revealed determinant morphological characteristics to distinguish peppers types and lines, which must complete their genetic improvement process.

Introduction. Bamboo as an agroforestry resource in Costa Rica includes introduced and native species, used in furniture manufacturing, which generates waste with potential to obtain carbonaceous materials. Objective. To analyze technologies and conditions for producing carbonaceous materials from bamboo and their application in a circular economy and bioeconomy model within the context of bamboo cultivation in Costa Rica. Development. The main processes are pyrolysis (slow, medium, and fast) and torrefaction, differentiated by the temperature applied: torrefaction occurs between 200 °C and 300 °C, while pyrolysis takes place between 350 °C and 700 °C. These conditions may vary according to the atmosphere used (CO2, N2, steam, air or minimum oxygen). Among the materials that can be obtained, activated carbon and biochar stand out, with recent research focused on applications in electronics and water treatment, as well as improving their use as fuel. However, many studies do not specify the bamboo species used or standardize the production processes and methodologies, as these depend on the physicochemical composition and region of cultivation. In the country, there is a lack of recent studies on productivity and cultivation areas to estimate the amount of carbonaceous materials that could be generated. Conclusions. There is an opportunity for research on bamboo cultivation in Costa Rica, covering agronomic aspects and the production of carbonaceous materials with high value-added applications, promoting a circular economy and bioeconomy model.

Introduction. Chionanthus pubescens Kunth is an endemic tree of southern Ecuador with ornamental uses in the villages of the region due to its pink inflorescence. Objective. To evaluate the effect of aqueous extracts of quinoa mojuelo (Chenopodium quinoa Willd.) on the growth of arupo plants (Chionanthus pubescens Kunth) and the incidence of Fusarium sp. Materials and methods. The trial was conducted in the province of Chimborazo, Ecuador, during 2022. Aqueous extracts of quinoa mojuelo were obtained using the Soxhlet method, and their concentrations were determined by UV-VIS spectrophotometry. A completely randomized block design with a bifactorial arrangement was used, with three levels for factor A (aqueous extract of mojuelo: mother extract at 100%, and 50 % and 75 % dilutions in sterile distilled water; v/v) and three levels for factor B (application frequency: every 7, 14, and 21 days). Ten treatments were evaluated, including an absolute control, with three repetitions each. In ten randomly selected plants per treatment, morphological variables (height, number of leaves per plant, and stem diameter) were measured, as well as the incidence of Fusarium sp. Results. The 50 % and 75 % aqueous extract concentrations applied weekly promoted better morphological development and reduced the percentage of Fusarium sp. incidence in arupo plants, as reflected in height (16.3 cm), number of leaves (17.8), stem diameter (6.5 cm), and disease incidence (50 %). Conclusions. Aqueous extracts obtained from quinoa mojuelo applied to Chionanthuspubescens Kunth plants in nursery conditions reduced the incidence of Fusarium wilt and favored their growth in the early stages of development.

Introduction. The charcoal rot fungus, Macrophomina phaseolina, is a ubiquitous necrotrophic phytopathogen that infecting soybean and other plant species. Despite its significant impact on crops, limited progress has been made in understanding the factors that influence phytotoxic molecule secretion by this phytopathogen. Objective. To evaluate the effect of soybean leaf infusion in the culture medium on the differential secretion of phytotoxic molecules of M. phaseolina. Materials and methods. The study was conducted between 2016 and 2023 at the Departamento de Química Biológica, Universidad Nacional de Asunción, Paraguay. Two fungal isolates were cultured in vitro using potato dextrose broth (PDB) and Czapek-Dox broth media, with or without soybean leaf infusion. Phytotoxic activity of secreted molecules was a using soybean leaf discs. The crude organic extract from the cultures was separated using chromatographic techniques, and purified metabolites were characterized by UHPLC-PDA/MS, HRMS (APGC), HRMSESI, 1HNMR and 13CNMR. Results. Molecules secreted by M. phaseolina FCQ11 cultured in infusion-enriched PDB induced the highest percentage of necrosis. Under these conditions, three differentially secreted metabolites were isolated and identified: (R)-mellein, (3R,4R)-hydroxymellein, and (-)-botryodiplodin. Conclusions. Soybean leaf infusion presence in M. phaseolina growth media stimulates phytotoxic metabolite production and alters the profile of secreted metabolites.

Introduction. The rearing of guinea pigs (Cavia porcellus) is key to the food supply and economy of Andean countries such as Peru. However, their productivity may be affected by inadequate management, including stocking density, whose impact has not yet been fully evaluated. Objective. To evaluate the productive efficiency of guinea pigs subjected to high stocking densities. Materials and methods. The experiment was conducted at the Small Animal Laboratory of the National Agrarian University La Molina (UNALM) in Lima, Peru, over eight weeks (January to March 2022). A total of 90 improved male guinea pigs of the Cieneguilla-UNALM genotype were used, with an average initial weight of 338.57 g (15 ± 3 days of age). The experimental design was completely randomized, with three treatments: 0.10 m²/animal (T1), 0.066 m²/animal (T2), and 0.050 m²/animal (T3), with three replicates of ten guinea pigs each. The animals were fed ad libitum with balanced feed and forage, with continuous access to water. The evaluated productive variables included initial and final weight, weight gain, feed intake (daily, weekly, and total), feed conversion ratio, mortality, carcass lesions, visible fat scoring, and carcass yield. Results. Treatment T1 showed the highest weight gain and total feed intake, while T3 exhibited the best feed conversion ratio and the lowest mortality among the productive variables. Carcass yield and visible fat content were higher in T1; however, T3 showed fewer signs of carcass lesions (p < 0.05). Conclusions. Stocking density in guinea pigs did not significantly affect the evaluated parameters, including weight gain, feed intake, feed conversion ratio, mortality, fat scoring, and carcass yield. However, the highest density (T3) reduced the incidence of lesions, indicating lower competitive behavior among the animals.

Introduction. In the dairy industry, frozen-thawed semen is crucial for artificial insemination and genetic improvement of cattle. Objective. To evaluate the variation in the kinematic subpopulation structure of frozen-thawed semen in Jersey and Holstein breeds using a CASA-mot system. Materials and Methods. The study was conducted from April to November 2023, at the Animal Reproduction Laboratory (AndroTEC), located at the Campus Tecnológico Local San Carlos, Alajuela, Costa Rica. Eight animals from the Holstein and Jersey breeds were used, and nine doses of frozen-thawed semen per animal were analyzed for each breed. A total of 72 semen doses from eight bulls (four from each breed) were thawed at 37 °C for 30 s. Sperm motility and kinematic variables were analyzed using CASA-mot (Computer-Assisted Semen Analysis) technology. Results. The Jersey breed presented higher percentages of total motile, progressive motile, and rapid spermatozoa compared to the Holstein breed (P < 0.05). Principal component analysis revealed two significant factors explaining 87.5 % of the total variance in kinematic variables. The kinematic variables between sperm subpopulations (SP) showed differences (P < 0.05) in both breeds. Subpopulation SP2 was the fastest, with higher values for curvilinear speed (VCL), straight-line speed (VSL), and average trajectory speed (VAP) in both Holstein and Jersey bulls. Conclusions. Kinematic differences were found between the identified subpopulations in both breeds. The kinematic patterns of the subpopulations present in the ejaculate could influence fertility and reproductive performance.

Introduction. Coffee cultivation in Ecuador plays a crucial role in social, economic, environmental, and cultural aspects. In Loja province, Coffea arabica production is distinguished by its high quality, attributed to both the geographical conditions and the cultivation practices under agroforestry systems (AFS) with different management approaches. Objective. To assess the composition, diversity, and importance value of shade tree species, and to identify the microclimatic conditions within coffee agroforestry systems. Materials and methods. The research was conducted in three coffee-producing areas of Loja, Ecuador, using 20 × 30 m plots monitored from November 2017 to April 2019. The importance value index (IVI), Shannon-Wiener, and Simpson indices were calculated. Microclimatic variables, including ambient temperature (°C), relative humidity (%), wind speed (m s⁻¹), and canopy cover percentage (%), were recorded both inside and outside the AFS. Pearson correlation analysis was used to examine relationships between microclimatic variables, number of shade-providing individuals, and their importance value. Results. The coffee-growing areas exhibited significant arboreal diversity in terms of families, genera, and shade tree species, with Citrus and Inga as predominant genera. Microclimate modifications were evident, with temperature differences (ranging from −4.23 °C to 2.23 °C) and relative humidity variations (ranging from 0 % to 10.54 %) compared to full-sun exposed areas. Conclusions. Coffee AFS modify environmental conditions between the interior and exterior of the evaluated areas, with variations directly influenced by canopy species within the systems.

Introduction. Insect-based foods represent an emerging alternative to conventional food products. Insect powders are an important protein source with reduced ecological impact, though its incorporation into foods should consider effects on sensory properties and nutritional profiles. Objective. To assess consumer acceptance of sweet biscuits with cricket powder in Costa Rica, and evaluate the nutritional profiles of the products developed. Materials and methods. The study was conducted at the Universidad de Costa Rica, San José, Costa Rica in 2023. Sweet biscuits containing varying proportions of cricket powder (0.0, 12.5, and 26.0 %) were manufactured to evaluate both placebo effect and effect of cricket powder content influence on consumer acceptance, using two distinct panel groups. Demographic information, attitudes towards entomophagy, and perceived importance of protein consumption were collected via questionnaire. Proximate analysis and detailed fatty acid composition were performed on the three tested formulations with cricket powder. Results. Study populations demonstrated positive attitude towards insect consumption. The overall acceptance of the “No cricket” sample was significantly lower compared to both “Cricket” and “Commercial” samples. Biscuits containing 12.5% cricket powered achieved significantly higher overall sensory acceptance compared to the “26.0 % cricket powder” sample and showed no significant difference from the “Commercial” sample. Consumer segmentation was accomplished through Agglomerative Hierarchical Clustering. Primary nutritional differences between samples were observed in crude fat and specific fatty acids contents. Conclusions. Results indicate high consumer acceptance of sweet biscuits with cricket powder in Costa Rica. Nutritional analysis revealed progressive increases in crude fat and specific fatty acids contents corresponding to increased cricket powder incorporation.

Introduction. Quality seed production is a limiting factor for bean cultivation in developing countries. Objective. To evaluate the effects of sun-drying at different exposure periods on the viability and vigor of bean seeds cv. ‘Cuba Cueto 25-9N’. Materials and methods. The study was conducted at the University of Artemisa, Cuba, from January to May 2024. Freshly harvested bean seeds cv. ‘Cuba Cueto 25-9N’ were sun-dried on jute sacks under three drying durations (24, 48, and 72 h) post-treatment seed moisture content and germination were evaluated as viability criteria. Vigor assessment included germination dynamics, emergence rate, electrical conductivity, and accelerated aging test. Data were analyzed using analysis of variance and means were compared using the Tukey’s test (p ≤ 0.05). Results. The 24 and 48 h drying treatments reduced seed moisture to levels that maintained both viability (92.66 and 84.33 % germination, respectively) or vigor. The 72 h drying treatment decreased moisture to 2.96 %, negativelyaffecting viability and vigor. Conclusions. Sun-drying of bean seeds for 24 and 48 h effectively reduced moisturewhile maintaining viability and vigor, contributing to the preservation of their physiological quality under resourcelimitedconditions. The 24 h treatment proved most efficient.