Nancy Arroyo- González

Coffee is one of the most important crops globally; however, it is not immune to diseases caused by various organisms that can reduce the quality and yield of its products. Therefore, the objective of this study was to isolate and purify phytopathogenic fungi from coffee crops to evaluate the fungicidal potential of Plectranthus amboinicus extract and compare its effectiveness with Origanum vulgare, which has proven efficacy against various pathogenic fungi and bacteria. The study was conducted on the Limani coffee variety in south-central Puerto Rico. In the field, Coffea arabica var. Limani plants exposed to different light conditions and exhibiting symptoms of fungal infection were selected. In the laboratory, the phytopathogenic fungi were isolated and purified, and morphologically identified using taxonomic keys. Additionally, an aqueous extract of P. amboinicus was prepared for disk diffusion testing to compare its effectiveness with a commercial oregano oil and a carvacrol standard. The phytopathogenic fungi Cladosporium, Aspergillus, and Fusarium were isolated. In the disk diffusion test, the results showed a significant difference in the ability to inhibit mycelial growth of the isolated fungi when using oregano essential oil or carvacrol (p ≤ 0.05). The P. amboinicus extract showed no inhibitory capacity for any of the samples. The use of essential oils with volatile compounds such as carvacrol can be incorporated into a preventive management plan for postharvest diseases. P. amboinicus was not effective in controlling Cladosporium, Aspergillus, and Fusarium isolated from coffee beans. Further bioprospecting of plants that produce secondary metabolites with potential for the treatment of fungal diseases is considered necessary.

Aedes aegypti is a culicide that has gained relevance over the years due to its ability to transmit various viruses that cause diseases in humans that all the years cause high mortality rates in the world population. The main problem is that Ae. aegypti has managed to establish and maintain a close relationship with humans and their habitat, which is why the search for alternatives to control vector populations becomes imperative. The objective of the present work was to study the effects of two Beauveria bassiana strains on Aedes aegypti. Third instar larvae of Ae. aegypti in 250 mL plastic containers were inoculated with the GHA and NB3 strains at different concentrations (1.5 × 104, 1.5× 105, 1.5 × 106 and 1.5 × 107 conidia/mL). The NB3 strain presented highest mortality values with 63% in the highest concentration i.e., 1.5 × 107, while for the GHA strain the highest mortality value was 30.7% at the same concentration. The results showed significant difference in mortality with respect to the strain and days post treatment (P = 0.0001), but not with respect to the conidial concentration (P = 0.634). The average mortality of larvae per day for the NB3 for different concentrations ranged from 20 to 25 larvae per day, while for the GHA daily mortality ranged from 5 to 12 larvae. In post-treatment mortality, the highest mortality was recorded in the third stage larvae for the NB3, while for GHA the highest percentage mortality was observed in individuals who managed to reach the adult state. The findings of the current research depicted the noteworthy role of B. bassiana for the management of an important vector of human disease.

La potenciación de los jóvenes como lideres transformacionales, representa una posibilidad para producir innovaciones en las instituciones universitarias y en la sociedad, ello implica preparar a los jóvenes por medio de diplomados, como medio de entrenamiento en un aprendizaje mediador, participativo y socioformativo. Este estudio tiene como objetivo, analizar la aplicación de estrategias de formación, para potenciar el liderazgo transformacional juvenil en la Facultad de Ciencias Económicas y Sociales de la Universidad del Zulia. Se realizó un diagnóstico a fin de identificar habilidades, competencias y actitudes de los estudiantes. La metodología utilizada fue la investigación acción- participante. La muestra, estuvo conformada por 12 estudiantes. En las técnicas utilizadas destacan la encuesta, con pre-test y pos-test y la observación de las conductas de los participantes. Entre los autores consultados destacan: Maxwell, Vygotsky, Chiavenato, entre otros. Los resultados muestran que dentro de las características y actitudes desarrolladas por los estudiantes se encuentran: capacidad de decisión, responsabilidad, confianza en sí mismo, liderazgo, capacidad de trabajar en equipo para dar cumplimiento a los proyectos ejecutados, entre otros. Como conclusión el enfoque sociocultural de Vygotsky se convierte en un método relevante en la intervención educativa para potenciar conocimientos y habilidades de liderazgo en los estudiantes.