Problem-based learning within link with society. Case study: Management of agrochemicals in rural communities

Authors

Quinchuela, Lorena

Vilalba, Ricardo

Pacheco, Yesenia

Abstract

Corral Quemado and Monte Oscuro, rural communities located in Santa Lucía, grow rice and apply agrochemicals to nourish the soil and control pests. However, this practice has caused health problems such as skin irritations, nausea, and headaches. Therefore, this work was carried out as part of a project to link with society. The project considered the participation of a multidisciplinary team of students from three careers: chemical engineering, biology and agricultural engineering. It was proposed to analyze the management of agrochemicals in the communities through the educational technique Learning Based on Problems. Teamwork, discussion, critical thinking, the execution of experiments and field visits in the analysis of the problem were encouraged. As a result, a list of 37 agrochemicals was generated, which were identified through field research in Monte Oscuro and Corral Quemado. Subsequently, bibliographical research was carried out to classify the products according to their level of danger and the personal protection equipment of each level was listed. Four levels of danger were considered: Extremely dangerous, Moderately dangerous, Slightly dangerous and Not Dangerous. 13.5% of the agrochemicals were classified as Extremely dangerous, while 32.5% were classified as Slightly dangerous. In addition, nine of the 37 agrochemicals were considered Non-hazardous. At the same time, the substitution of agrochemicals was proposed, for which all the students designed experiments to evaluate ten organic inputs made from organic waste or accessible natural products such as garlic, onion and chili. The design of experiments considered qualitative or quantitative input and output variables that were measured weekly. Some of the input variables were: dose, percentage of ingredients, type of ingredients and sampling time. The output variables were: plant height, number of leaves, fruit weight, number of insects, appearance, color and leaves attacked by insects. Eight of the prepared inputs presented favorable results for pest control or soil nutrition. Finally, it was identified that the inputs with low effectiveness were the liquid amendments due to their high acidity. In conclusion, the Problem-Based Learning methodology allowed us to identify an important group of agrochemicals that are used in agriculture in Monte Oscuro and Corral Quemado, as well as possible alternatives to their use. It is hoped that in the near future, this information will be transmitted to farmers in order to prevent possible damage to health and the environment and contribute to the sustainability of these rice-growing communities.