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

The article seeks to outline the complex relationship between the construction of the Brazilian historiographical and literary canon and the production of silencing/coloniality, thus understanding the canon as a technology of power that reproduces racialization. To address this issue, we divided the article into two parts. In the first part, we outline how the foundation of the discipline of History was based on systemic silencing and on the figure of the White Savior, fundamental axes for the racialization of the writing of history, and also approaching some alternatives. Then, we deepen this reflection from the literary dimension, rethinking how the construction of this canon silences and masks the immense pluriversality of fictional/non-fictional narratives, thus exploring how dissident narratives (black and anti-racist) reorganize the order of the canon.

It is a review of a recently published book

It is a review of a recently published book

Es la reseña de un libro reciente

Introduction. The giant squid (Dosidicus gigas) is a species of great abundance and considered as potential resource to meet the demand for protein in Peru. Giant squid meal represents an alternative to traditional proteins which can be used in food fortification. Objective. To optimize the extraction process and identification of soluble protein from giant squid meal (GSM). Materials and methods. This study was conducted at the Universidad Nacional Agraria La Molina, Lima, Peru, between 2018 and 2019. To obtain the highest yield of soluble protein (Ŷ) extracted, an alkaline extraction method using NaOH followed by acid precipitation at pH 4.5 was applied. Surface response methodology was used to determine the optimal parameters for protein extraction such as temperature, concentration of NaCl, time, and the ratio GSM: solvent. A 1D and 2D electrophoresis study was carried out to find the distribution of molecular weights and to identify the main proteins of GSM. Results. Values for optimal response were the concentration of NaCl 0 M, an extraction time of 35 min, the ratio GSM: solvent of 1:31.72, and a temperature at 71.9 ºC. The molecular weights of the proteins detected were in the range of 6.5 and 38.37 kDa, which would correspond to tropomyosins, troponins, and myosin light chain residues. Conclusions. This study allowed to optimize the extraction parameters and to identify soluble proteins corresponding to the sarcoplasmic fraction of the giant squid meal (GSM), which could be used in the food industry.    

Introduction. Rhizobium has been used as a growth stimulator in leguminous. Different species of this group are associated with chickpea (Cicer arietium L.), so it is important to obtain isolated with capacity of benefitting their growth and productivity. Objective. To select and identify isolates of Rhizobium sp. in terms of their attributes as plant growth-promoting rhizobacteria with greater effectiveness in their association with chickpea cultivars. Materials and methods. The studies were carried out during the years 2017-2020, at the Instituto de Investigaciones Fundamentales en Agricultura Tropical “Alejandro of Humboldt”, Havana, Cuba. Three rhizobia strains, obtained from chickpea nodules were identified by 16S RNA gene sequencing and characterized for their potential as growth-promoting bacteria. An experiment was carried out in field conditions in two campaigns to demonstrate their effectiveness in the interaction with plants. For the experiments under laboratory conditions a completely randomized design was used, while the field trials were conducted under a randomized block design, in both cases an analysis of variance was performed. Results. The three bacterial strains associated with chickpea and identified as Rhizobium sp. fixed atmospheric nitrogen, solubilized calcium phosphate, released phytohormones and were able to inhibit the growth of Fusarium oxysporum, Fusarium incarnatum, and Fusarium moniliforme. Inoculation in chickpea increased the nodulation and the crop yield variables such as number of pods per plant and fresh grain mass (g). Conclusions. Rhizobium sp. strains were identified with attributes as plant growth-promoting bacteria associated with national chickpea cultivars, that increased their nodulation and yield.

Introduction. Pastures are the primary source of food in livestock systems and can be a suitable niche for insects with beneficial and harmful functions. Objective. To estimate the entomofauna associated with three species of pastures, Cenchrus ciliaris, Chloris gayana, and Megathyrsus maximus, in conditions of the Colombian Caribbean. Materials and methods. Ten samplings were carried out in two contrasting periods (August to October 2018 and January to March 2019), three forage species (Cenchrus ciliaris, Megathyrsus maximus, Chloris gayana) within 1000 m2 were used. Arthropods were identified by order and family and typified by functional groups. Diversity and abundance indices by pasture and season were estimated, as well as their correlation with climate. A simple correspondence analysis was performed. Results. A total of 380 insects from 7 orders and 35 families were collected, with the greatest abundance for Hemiptera and Coleoptera. The Shannon’s diversity index was higher for all orders of C. gayana, except for Hemiptera in C. ciliaris. Phytophages were found in a higher percentage (66.84 %), followed by predators (27.11 %). Insect abundance was influenced by the interaction between season and pasture, showing an increase at low temperatures, except for M. maximus. Pastures represented adequate microenvironments to maintain the diversity of insects, the Hemiptera and Coleoptera orders being the most numerous and representative of the functional groups of phytophages and predators, respectively. Conclusion. The entomofauna of C. gayana, C. ciliaris, and M. maximus was similar in insect abundance and diversity, however, insect abundance depended on the influence of the season and pastures.

Introduction. Genetic diversity, registration, and traceability of cacao planting material are the essential tripod to support its sustainable cultivation. In Nicaragua, cocoa planting material is mostly obtained from seeds, which leads to great variability in yield, bean quality, and tolerance to pests and diseases. Farmers, technical staff, development projects, and investors depend on a limited supply of elite trees as a reliable source of genetic material to support new cacao fronts and meet market quality standards. Therefore, the development of a national genetic improvement program and a planting material traceability system in Nicaragua are necessary to improve the sustainability of cacao cultivation. Objective. To evaluate the genetic resources on farms and provide information for future breeding programs, as well as to lay foundation for a national traceability and certification system. Materials and methods. Fourty-nine elite trees selected by farmers in the main producing regions in Nicaragua between 2018 and 2020 were sampled. Ninety-three SNP markers were used to characterize them and resolve their genetic origins. Results. The evaluated cacao trees had a narrow genetic background, mainly composed of hybrids with Amelonado (36 %), Criollo (17 %) and Iquitos (15 %) origins. A set of trees with high genetic diversity that could be incorporated into a selection and breeding program was identified. Conclusion. Fingerprinting with SNP markers was a useful tool for evaluating the genetic links of cultivated cacao and can be used for varietal identity test at the farm level. The study provided the basis for developing both a breeding program and a traceability system of cacao planting material in Nicaragua.

Introduction. There is worldwide interest in determining the content of plant-based antioxidant substances, and the relationship of the phenological phases of the plant with the production of secondary metabolites. Objective. To determine the effect of phenological phases on the content of antioxidant substances of guava (Psidium guajava L.). Materials and methods. A population sample of 10 % of guava plants from the germplasm bank of CESID-Frutícola y Apícola-CORPOZULIA, located in the municipality of Mara, Zulia state, Venezuela, was evaluated. The content of total phenols (FeT), total flavonoids (FlT), and antioxidant capacity (CA) were determined in dry leaves samples at different phenological phases of the plant, recorded from October 2012 to September 2013. Extraction of the FeT was performed by ultrasound with 0.5 g of dry sample and a methanol: water mixture (80:20 % v/v). For quantification by UV-VIS absorption spectrophotometry, gallic acid for FeT and catechin for FlT were used as standard. The AC was determined by the cation-radical ABTS▪+. Non-parametric statistics were used using SPSS statistical software. Results. The three phenological phases (flowering, fruiting, vegetative sprouting) occurred in guava plants, the reproductive phase prevailed with 38.99 % of flowers and fruits; with higher average presence of vegetative shoots that occurred during the rainy season and the alternation between flowers and fruits production. Intra-population variability was observed in the content of antioxidant substances, FeT content, compared to CA and FlT, was higher in fruiting and in the absence of precipitation. Conclusion. The phenological phases had an effect on the content of antioxidant substances of guava. The fruiting phase had the highest content of total phenols. The contents of total phenols and flavonoids were related to antioxidant capacity.

Introduction. Interest in consuming fresh products such as vegetables has been increasing over the years. Different cultivation methods to produce vegetables such as carrots, tomatoes, and cabbages are available. Conventional and organic farming systems are the most common. Objective. To compare the microbiology of carrot, tomato and cabbage from farms with organic or conventional agricultural production systems in Costa Rica. Materials and methods. Sampling was carried out in Cartago, Heredia and Alajuela, Costa Rica, from September 2020 to November 2021, during the rainy season in all cases. Vegetables from model farms of carrot, tomato and cabbage, one of organic production and three of conventional production, were sampled. Microbial counts of total aerobic mesophilic, total coliforms, Escherichia coli, yeasts and molds, and the absence/presence of Listeria monocytogenes were determined. Results. Total aerobic, yeast and mold and total coliform counts for conventionally and organically grown carrots, cabbages, and tomatoes did not differ from each other. In the vegetables studied, E. coli counts were <1 log CFU/g and Listeria monocytogenes was absent. Presence of Listeria sp. in carrot samples from conventional cultivation was found in contrast to its absence in carrots from organic cultivation. Conclusions. L. monocytogenes was absent in the vegetables studied, which in general had acceptable microbial loads according to regulations and similar to studies reported worldwide. Under controlled conditions, when compared to those obtained from conventional production systems, it is possible to obtain vegetables from organic farming without detriment to their microbiological quality and with the derived benefits for the health of the consumer and the environment.