Centrosur Agraria

Selection of coffee genotypes resistant to rooster's eye [Mycena citricolor (Berk. & M.A. Curtis) Sacc.]

2026-07-01T20:06:02-04:00

To evaluate the use of oxalic acid in selecting genotypes resistant to coffee leaf rust (Mycena citricolor (Berk. & M.A.Curtis) Sacc.), an experiment was conducted using a completely randomized design (CRD) with an unbalanced layout and 55 treatments at the UNESUM Biotechnology Laboratory. Ten genotypes were placed per tray, with two individual leaflets per genotype, for a total of 11 trays. Each leaflet was inoculated with three drops on each side of the midrib at a concentration of 2.25 g/150 mL of oxalic acid. Lesion size (LS) was measured in millimeters using a Vernier caliper starting on the third day, with daily readings continuing for six days. Using the LS data, the area under the relative lesion progression curve (AULRP) was determined as a relative measure over time. Analysis of variance (ANOVA) and comparison of means were performed using Tukey’s multiple range test (P < 0.05), after verifying that the assumptions of normality and homogeneity of variances were met. Additionally, the best-fit curve was determined using the regression coefficient (^R²). The results showed that genotypes 021-101-4 and 021-101-3 exhibited high resistance to necrosis caused by oxalic acid. Genotype 021-106-4 was the most susceptible, as were the cultivars Gheisha and Típica; thus, different levels of resistance to oxalic acid were identified, ranging from the most resistant to the most susceptible. Both the progenies and the parent lines evaluated had a logarithmic regression fit.

The Use of Socio-Scientific Problems to Develop Critical Thinking in the Teaching of Natural Sciences

2026-07-01T20:13:43-04:00

This study analyzes the use of socio-scientific problems as a strategy for developing critical thinking in the teaching of natural sciences. The objective of the research was to identify teachers’ perceptions and practices regarding the integration of this approach in the classroom. The research was conducted using a mixed-methods approach, combining a literature review on the topic with a survey of 22 teachers at the Edwards Deming Corporate University Technological Institute (ISTUCED). The results show that most teachers use socio-scientific problems in their classes, primarily when covering course content and through strategies such as case studies and classroom debates. Furthermore, teachers believe that using these problems fosters the development of critical thinking, connects scientific knowledge to real-world situations, and promotes informed decision-making. Among the skills developed, scientific reasoning, information analysis, and evidence-based decision-making stand out. However, difficulties related to a lack of teacher training and limited time within the curriculum were also identified. In conclusion, socio-scientific problems constitute a relevant teaching strategy for promoting a more contextualized and reflective approach to science education.

Environmental Training and Awareness as a Key Factor in the University Community’s Environmental Perception and Culture

2026-07-01T20:30:43-04:00

Environmental training and awareness have become strategic elements for promoting significant changes in attitudes, behaviors, and sustainable practices within higher education institutions. This scientific article aims to analyze the influence of environmental training and awareness programs on the environmental perception and culture of the university community. The research was conducted using a mixed-methods approach—descriptive and documentary—supplemented by surveys administered to students, faculty, and university administrative staff. The results showed that the implementation of environmental education strategies strengthens institutional commitment to sustainability, increases participation in ecological activities, and improves perceptions of collective environmental responsibility. Furthermore, it was found that universities play a fundamental role in educating environmentally responsible citizens through comprehensive educational policies and ongoing awareness programs. It is concluded that environmental training is a determining factor in consolidating a university environmental culture oriented toward sustainable development and

Evaluation of the Nutritional Content of Two Varieties of Fresh and Silage-Processed Pitahaya Stems as an Alternative Animal Feed

2026-07-01T20:36:50-04:00

The pitahaya (Selenicereus spp.) crop is notable for its adaptation to arid conditions and its productive potential. The objective of this study is to evaluate the nutritional content of pitahaya stems (Selenicereus undatus and Selenicereus costaricensis) in both fresh and silage forms. The study was conducted using a completely randomized design with a 2×2 factorial arrangement, considering variety and preservation state as factors, and analyzing bromatological variables such as moisture, dry matter, ash, fat, carbohydrates, fiber, organic matter, Brix degrees, and protein. The results showed that in the fresh state, S. costaricensis had higher moisture (93.7%) and protein (0.74) content, while S. undatus had higher values for dry matter (9.78%), carbohydrates (7.08%), and ash (0.34%). Regarding the ensiled state, both varieties showed an increase in nutrient concentration, with S. undatus standing out for its higher dry matter content (11.4%), carbohydrate content (8.29%), and Brix degrees (7.5°), indicating an improvement in the material’s energy value. analysis of variance revealed highly significant differences (p<0.0001) for variables such as moisture, dry matter, and Brix degrees, influenced by both the variety and the silage process. It was concluded that pitahaya stems have high moisture content and low protein levels; their use is intended as an energy supplement that is rich in fiber and low in protein.