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

Introduction. Over the last few decades, there has been growing interest on the part of consumers in sustainable agri-food products. As a result, voluntary standards have emerged as a tool to promote sustainability in production and consumption in agri-food value chains. Objective. To evaluate the profile of consumers and the degree of knowledge of sustainability seals for agricultural products in Costa Rican markets. Materials and methods. During October and November 2021, a nationwide virtual survey was conducted through the Qualtrics platform, from which 397 valid responses were collected. The sustainability seals considered were certifications of organic production, fair trade, denomination of origin, nation brand Essential Costa Rica, and carbon neutral. The Poisson regression model (PRM) was used to study the behavior of the variables, using Stata software version 16.0. Results. The Essential Costa Rica seal is the most recognized. People residing in the Greater Metropolitan Area (GAM) are more familiar with various seals. The income variable turned out to be a significant factor; those with higher incomes tend to identify and value sustainability seals more. The levels of knowledge and consumption of certified products increase when the consumer has some link to the agricultural sector. Conclusions. People’s interest in certified products is not reflected in their purchasing behavior, due in part to the price of the products, lack of trust or excessive information on labels. The findings of the study allow companies to define their marketing strategies according to the characteristics of the consumers of these differentiated products.

Introduction. The determination of antioxidant components of native fruits is important for their incorporation into the diet and for their better use and conservation. Objective. To evaluate the activity of the antioxidant enzymes catalase (CAT), peroxidase (POX), superoxide dismutase (SOD) and glutathione sulfhydril transferase (GST), of aqueous extracts of ripe and unripe pulp of the fruit of Vasconcellea candicans (A. Gray) A. DC (“mito”, “andean papaya”) and relate them to their concentration of total polyphenols (PT). Materials and methods. The pulp of four fruits, ripe and unripe, of “mito” from Santo Domingo de Los Olleros, Huarochirí, Lima, Peru, was extracted and processed during March to December 2023. The samples were obtained by aqueous extraction of 20 g of pulp in a 20:80 ratio in water at 8 °C for 15 days (cold maceration technique), using the supernatant after centrifugation. The determination of PT was performed by spectrophotometry using gallic acid as standard. The determination of the specific activity of the enzymes was performed by spectrophotometry using the respective standards. Non-parametric statistics were applied using the statistical software R. Results. The fruits of V. candicans show marked differences between stages of ripeness, particularly in protein content and in the activity of antioxidant enzymes such as CAT, SOD and GST. Biochemical correlations are more pronounced in ripe fruits, indicating a functional reorganization of antioxidant components during ripening. Conclusions. The results suggest that CAT activity, together with polyphenol levels, could be used as a biochemical indicator of the degree of fruit ripeness, which could be used to determine and optimize the post-harvest shelf life of the fruit.

Introduction. Bougainvillea glabra is an ornamental plant that has gained scientific attention due to its medicinal potential, therapeutic properties, and toxic effects. Objective. To evaluate the effect of three drying temperatures (50, 55, and 60 °C) on the phytochemical and functional characteristics of Bougainvillea glabra flowers. Materials and methods. The analyses were conducted from July to September 2024 in Chone canton (Ecuador). Flowers were collected in self-sealing bags and transported to the Chemistry and Bromatology Laboratory of the Faculty of Agricultural Sciences (Chone), Universidad Técnica de Manabí, Ecuador. This experimental research followed a completely randomized design consisting of three treatments (T1: 50 °C, T2: 55 °C, and T3: 60 °C). Drying kinetics were studied using a FD-12 dehydrator, and moisture loss was monitored using an analytical balance. Ground samples underwent aqueous extraction through maceration and filtration. Phytochemical screening was performed, and antioxidant capacity of the plant was assessed using ABTS (2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)-diammonium salt) and DPPH (2,2-diphenyl-1-picrylhydrazyl radical) methods. Results. Higher drying temperatures resulted in greater plant material weight reduction. Phytochemical screening showed that drying temperature affected the presence of saponins and flavonoids; however, levels of tannins, free amino acids, and alkaloids remained stable. Catechins, triterpenes, reducing sugars, anthocyanins, and resins were not detected. Antioxidant activity analyses revealed that drying temperatures did not affect the DPPH results, while lower temperatures yielded higher antioxidant capacity in the ABTS method. Conclusions. Drying at 55 °C and 60 °C promoted greater weight loss, but negatively impacted the presence of saponins and catechins.

Introduction. Sausages are products that are consumed worldwide and that allow the use of not only this type of meat but of other underused raw materials, such as the case of grapefruit (Citrus x paradisi L.) albedo, which is a subproduct of the citrus industry that has fiber and antioxidants that are important for human health. Objective. To evaluate the effect of adding debittered grapefruit albedo flour on the physicochemical, sensory, and microbiological characteristics of ultra-low-fat duck ham. Materials and methods. The study was conducted at the Faculty of Technical Education for Development at the Catholic University of Santiago de Guayaquil, Ecuador, between September 2022 and August 2023. Four treatments were formulated, with the addition of 0 %, 2 %, 4 %, or 6 % grapefruit albedo flour. The hams were evaluated for physical-chemical parameters (pH, titratable acidity, moisture content, ash, protein, fiber, fat, total phenols, and antioxidant capacity); technological properties (emulsion stability, yield, water-holding capacity); sanitary aspects (aerobic mesophilic microorganism count, Escherichia coli, Staphylococcus aureus, and Salmonella); texture profile analysis; sensory evaluation (acceptance test, purchase intention, check all that apply) with 41 consumers. Results. The produced products met sanitary and compositional standards. The addition of grapefruit albedo flour increased antioxidant capacity, fiber content, and water-holding capacity. All products received a rating equivalent to “Moderately Liked.” Although hardness and elasticity decreased with increased flour content, texture acceptance was not affected. Conclusions. It is possible to produce duck hams by incorporating up to 6 % debittered grapefruit albedo flour, resulting in good acceptance, higher fiber content, and enhanced antioxidant capacity.

Introduction. From 2016 to 2022, both the planted area and rice production in Mexico experienced a declining growth rate, leading to an increase in rice imports, to meet the excess demand. Objective. To econometrically evaluate the factors affecting rice production in Mexico by technology type, differentiating between irrigation and rainfed systems. Materials and methods. A dynamic simultaneous equation model was formulated, comprising two supply equations, three price transmission models and one identity; with annual data from 1980 to 2022 on rice production in Mexico (differentiated by type of technology), as well as the prices of competitive products, tradable inputs and climatic variables that determine them. To estimate the model, the two-stage least squares method (2SLS) was used and its statistical congruence was determined by means of the global significance of each equation through the F test, its level of autocorrelation via the Durbin Watson statistic, the individual significance of each coefficient through the Student t test and the normality of the variables with the Shapiro-Wilk test. Results. The own-price elasticities of the supply for irrigated and rainfed rice were 0.6995 and 0.3871, respectively. The price of competitive goods, particularly corn (-0.9896 and -1.2284) and wheat (-0.5279 and -0.9529), had the greatest impact on both types of supply. Conclusion. The rice supply, both irrigated and rainfed, responds positively to changes in producer prices, water availability for irrigation, and average annual rainfall recorded in the country and negative responses were observed to changes in producer prices of competitive goods such as beans, corn, wheat, lentils and chickpeas, and in inputs such as the price of pesticides and fertilizers.

Introduction. Various plant extracts are used in agriculture to reduce the impact on arthropod pests. However, there are few works that indicate the toxic or repellent action of essential oils of cinnamon, citronella and ginger on populations of phytophagous mites such as Tetranychus urticae. Objective. To evaluate the repellent effect of commercial grade essential oils of cinnamon (Cinnamomum zeylanicum), citronella (Cymbopogon winterianus) and ginger (Zingiber officinale), on a population of the mite Tetranychus urticae on sweet chili plants (Capsicum annuum) under in vitro conditions. Materials and methods. The research was conducted in the Acarology Laboratory at the Crop Protection Research Center, School of Agronomy, University of Costa Rica, located in San Pedro de Montes de Oca, Costa Rica, between October and November 2023. Four different concentrations (1%, 2%, 3%, and 4%) of each essential oil (cinnamon, citronella, and ginger) were tested at a volume of 333 µL per leaf. The repellent activity was quantified through a restricted choice test using paper bridges. Evaluations were conducted 24 and 48 hours after application. The experimental design was a randomized complete block design, and data analysis was performed using a Generalized Linear Model. Results. The three oils and their respective concentrations showed repellent action greater than 60% except for citronella oil at 2%. A high concentration did not always show the greatest repellency against mites, although this changed according to the essential oil used. Conclusion. This research showed that cinnamon, citronella and ginger oils have repellent properties against Tetranychus urticae, and demonstrates its potential as an alternative for the management of this pest.

Introduction. Varroa destructor is one of the main causes of mortality in Apis mellifera colonies, thus requiring constant control measures are required. Objective. To evaluate the efficacy of using rue oil and oxalic acid to control V. destructor in honeybees (Apis mellifera). Material and methods. The study was conducted in commercial honeybee hives located in two areas of the city of Ambato, Tungurahua, Ecuador, from April to May 2023. Oxalic acid (5 and 10 g) and rue oil (10 and 15 %) were applied by sublimation or impregnated strips, respectively, and a control treatment (without applications) was used. Three applications of each treatment were made at eight-day intervals. at 96 h after application. A completely randomized design was used. Results. The highest mite mortality was obtained increasing the oxalic acid with dosage and exposure time. Oxalic acid (5 and 10 g) reduced Varroa infestation by 92.3 and 84.9 %, while rue essential oil at 10 and 15 % caused 68.0 and 76.5 % of mortality, respectively. Concomitantly, control efficiency increased over time, being significantly higher in hives treated with sublimed oxalic acid. Conclusion. Due to the effectiveness of oxalic acid and rue essential oil in controlling varroosis, and their safety for bees, they may be an alternative to be included in an integrated management program for V. destructor in beekeeping.

Introduction. Simulation models are a tool to study the behavior of crops under different climatic and water conditions and agronomic management practices. Objective. To evaluate the AquaCrop model for yield and water productivity in soybean var. CIGRAS-06. Materials and methods. The study was carried out at the Estación Experimental Agrícola Fabio Baudrit Moreno of the University of Costa Rica, in Alajuela, Costa Rica from June 6th to October 23rd 2018. The AquaCrop v 7.1 model was used to simulate the development of soybean cultivation. Simulated data of plant canopy cover, biomass production and yield were compared against experimental data from a plot of soybean variety CIGRAS-06. Soil parameters measured in the field and generated using pedotransfer equations were used. Results. The predictions of yield, total biomass, and coverage were good (similarity values (d) ≥ 0.97), but the predictions of leaf coverage during the beginning of the crop cycle are should be improvement. Differences observed in the two types of soil parameters used, did not significantly affect the final simulation. Conclusions. Overall, modeling with AquaCrop successfully simulated soybean yield, biomass, and leaf coverage. The simulation of water productivity was higher than other values reported in the literature.

Introduction. The use of microbial consortia (CM) combined with adequate plant densities (DP) can be a viable and friendly alternative to increase sunflower (Helianthus annuus L.) sustainable production. Objective. To determine the individual and combined effects of microbial consortia and plant densities on sunflower growth and yield under water-deficit conditions. Materials and methods. An experiment was carried out under field conditions distributed in split-plots, in a randomized block design with three replications. The main plots were two DP (20,000 and 40,000 plants ha-1) and the secondary plots were three concentrations of the CM (0, 100, and 200 mL m-2). Results. Results showed that individually DP and CM directly influenced sunflower growth and yield The DP of 40,000 plants ha-1 favored plant height, leaf area index, percent of full seeds, seed mass per head, and yield. The DP of 20,000 plants/ha influenced leaf area, chlorophyll content, head diameter, and total and full seed per head. Additionally, the concentrations of 100 mL m-2 of CM stimulated plant growth and yield in both densities compared to the treatments without CM and with 200 mL m-2 of CM. Conclusions. The findings of this study indicate that the combination of a density of 40,000 plants/ha and inoculation with 100 mL m-2 of CM could be considered a local, viable, important and friendly strategy to increase sustainable sunflower production under low rainfall conditions.

Introduction. Research focused on developing models to predict flowering curves and key production parameters in banana has made notable progress. However, there is still a need for specific models capable of accurately estimating crop harvest. Objective. To develop a model based on biometric variables for predicting harvest in banana (Musa AAA), cultivar Gran Enano, under humid tropical conditions in Guácimo, Limón, Costa Rica. Materials and methods. A correlational study was conducted on a commercial farm owned by EARTH University between March and July 2023. A total of 347 productive units were evaluated across 10.3 hectares. Biometric variables such as plant height, pseudostem circumference, and number of leaves were measured on both the mother plant and the following ratoon. Harvest variables assessed included bunch weight, number of hands, finger length, and finger diameter for both the second and penultimate hands. A multiple linear regression model without intercept was applied to all dependent variables, with assumption validation procedures. Results. The height and pseudostem circumference of the mother plant showed the strongest and most significant correlations with harvest variables. The most effective model, based on assumption validation, was the second model designed for bunch weight prediction (mod2_peso), which produced the following equation: Peso=0.13CircunferenciaM + 6.06AlturaM + 0.46CircunferenciaH - 9.38HojasH - 0.63AlturaH with an R2 of 0.96 where M denotes the correlation between mother plant variables and various harvest-related parameters. Conclusions. The analysis revealed a significant correlation between mother plant variables and various harvest-related parameters. The results highlight the importance of considering the biometric characteristics of the follower (ratoon) plant in predictive models. Furthermore, the coefficient of determination (R2) should not be used as the sole criterion for validating multiple linear regression models.