ABSTRACT Calcium (Ca) is a nutrient responsible for maintaining plant quality and fruit yield. The production of new Ca sources, such as micronized (CaM) and complexed Ca (CaC), and their supplementation provide a better yield in mango cultivation. This study aimed to evaluate the efect of Ca sources (micronized and complexed with Ascophyllum nodosum) and application methods on mango cultivation, in semi-arid Brazil. The experimental design was randomized blocks, in a 6 × 6 factorial scheme. The Ca supplementation strategies (control; 1 L ha−1 of CaM; 2 L ha−1 of CaM; 2 L ha−1 of CaC with A. nodosum extract; 2 L ha−1 of CaC with A. nodosum extract + application of 2.5 L ha−1 via CaC fertigation; and 2.5 L ha−1 via CaC fertigation) were evaluated on six dates regarding nutritional aspects. For biochemical and production aspects, the six supplementation strategies with Ca were evaluated. The Ca concentration in leaves and fruits signifcantly afected the interaction among the factors. The fertilization strategy with 2.5 L ha−1 of complexed calcium via fertigation was fundamental to provide increases in the nitrogen and Ca concentration of the fruits from 65 days after full fowering, and had positive efects on fruiting and production of mangoes cv. Kent.

RESUMO O cálcio (Ca) é um nutriente responsável por manter a qualidade de plantas e o rendimento de frutas. A produção de novas fontes de Ca, como o Ca micronizado (CaM) e o Ca complexado (CaC), e sua suplementação proporcionam um melhor rendimento no cultivo de mangueiras. Avaliou-se o efeito de fontes de Ca (micronizado e complexado com Ascophyllum nodosum) e métodos de aplicação no cultivo de mangueiras, no semiárido brasileiro. O delineamento experimental foi em blocos ao acaso, em esquema fato rial 6 x 6. As estratégias de suplementação de Ca (controle; 1 L ha−1 de CaM; 2 L ha−1 de CaM; 2 L ha−1 de CaC com extrato de A. nodosum; 2 L ha−1 de CaC com extrato de A. nodosum + aplicação de 2,5 L ha−1 via fertirrigação de CaC; e 2,5 L ha−1 via fertirrigação de CaC) foram avaliadas em seis datas, quanto aos aspectos nutricionais. Para aspectos bioquímicos e de produção, as seis estratégias de suplementação com Ca foram avaliadas. A concentração de Ca nas folhas e frutos afetou signifcativamente a interação entre os fatores. A estratégia de fertilização com 2,5 L ha−1 de cálcio complexado via fertirrigação foi fundamental para proporcionar aumentos na concentração de nitrogênio e Ca nos frutos a partir de 65 dias após a foração completa e teve efeitos positivos na frutifcação e produção de mangas cv. Kent.

ABSTRACT This paper presents the report of an experience carried out in the hinterland of Pernambuco, through the HackTown Academy Project, which promotes teaching activities that enhance computational thinking in children aged 7 to 10 years old, through programming courses in games and robotics. The courses offered make use of methodologies such as gamification, unplugged computing, game learning, storytelling, reading club, educational robotics, and programming, and they adopt the ludicity in the proposed activities and understand that methodological diversity promotes meaningful learning.

RESUMO Este trabalho apresenta o relato de experiência realizada no sertão de Pernambuco, por meio do Projeto Academia HackTown, que promove atividades de ensino que potencializam o pensamento computacional em crianças de 7 a 10 anos, em cursos de programação em jogos e robótica. Os cursos oferecidos fazem uso de metodologias como gamificação, computação desplugada, game learning, storytelling, clube de leitura, robótica educacional e programação, bem como adotam a ludicidade nas atividades propostas e compreendem que a diversidade metodológica promove a aprendizagem significativa.

The significant growth in the use of smartphones in recent decades has led to a change in how people relate to the internet. Also, in this way, it is expected that what is conventionally called the Metaverse will drastically impact the way society lives and understands technology. For this reason, teachers and educators must understand and take ownership of these technologies while the Metaverse is being built. In order to understand how the immersive tools of the Metaverse have been used, with a particular focus on the educational context, a systematic literature review was conducted using the Scopus and Web of Science databases. In addition, documentary research was performed based on technical reports from companies interested in the Metaverse. It was possible to perceive that researchers and entrepreneurs are still trying to understand the Metaverse and how it could be and that studies, especially in the educational area, are still very embryonic.

El importante crecimiento del uso de los smartphones en las últimas décadas ha supuesto un cambio en la forma en que las personas se relacionan con internet. También de esta manera, se espera que lo que convencionalmente se denomina Metaverso impacte drásticamente en la forma en que la sociedad vive y entiende la tecnología. Por esta razón, es esencial que los maestros y educadores entiendan y se apropien de estas tecnologías mientras se construye el Metaverso. Para entender cómo se han utilizado las herramientas inmersivas del Metaverso, con especial foco en el contexto educativo, se realizó una revisión sistemática de la literatura a partir de las bases de datos Scopus y Web of Science, a la que se sumó una investigación documental basada en informes técnicos de empresas interesadas en el Metaverso. Se pudo percibir que los investigadores y empresarios todavía están tratando de entender qué es el Metaverso y cómo podría ser, y que los estudios, especialmente en el área educativa, aún son muy embrionarios.

O expressivo crescimento do uso de smartphones nas últimas décadas levou a uma mudança na maneira como as pessoas se relacionam com a internet. Também desta forma, espera-se que o que convencionou-se chamar de Metaverso vá impactar drasticamente a maneira como a sociedade vive e entende a tecnologia. Por este motivo, é primordial que professores e educadores compreendam e se apropriem destas tecnologias enquanto o Metaverso está sendo construído. A fim de compreender como as ferramentas imersivas do Metaverso têm sido utilizadas, com especial foco no contexto educacional, realizou-se uma revisão sistemática da literatura a partir das bases de dados Scopus e Web of Science, e somou-se a isto uma pesquisa documental a partir de relatórios técnicos de empresas e companhias interessadas no Metaverso. Foi possível perceber que pesquisadores e empreendedores estão ainda buscando compreender o que é e como o Metaverso poderá ser, e que os estudos, especialmente na área educacional, são ainda muito embrionários.

RESUMO Esta pesquisa objetivou avaliar a eficiência de uso de fósforo em genótipos de meloeiro cultivados em sistema hidropônico. Foram avaliados 10 genótipos de meloeiro em soluções nutritivas com e sem restrição de fósforo. Utilizou-se o delineamento em blocos casualizados no esquema fatorial 10 × 2, com cinco repetições. Foram avaliados os seguintes caracteres: número de folhas, diâmetro do caule, comprimento do ramo principal, comprimento do sistema radicular, volume do sistema radicular, clorofila, razão do teor de fósforo na raiz e parte aérea, fósforo total, razão da matéria seca na raiz e parte aérea, matéria seca total e eficiências de uso, de aquisição e de utilização interna de fósforo. Verificou-se a existência de variabilidade entre os genótipos para todos os caracteres avaliados, exceto para clorofila. Os genótipos A-16, A-29, A-50, A-52 e Trinity foram classificados como eficientes e responsivos na solução com restrição de fósforo, sendo promissores para estudos em melhoramento genético.

ABSTRACT This study aimed to evaluate the efficiency of phosphorus use with melon genotypes cultivated in a hydroponic system. Ten melon genotypes were evaluated in solutions with and without phosphorus restriction. A randomized block design in a 10 × 2 factorial scheme was used, with five replicates. The following characteristics were evaluated: leaf number, stem diameter, main branch length, root system length, root system volume, chlorophyll, root and shoot phosphorus concentration ratio, total phosphorus, root and shoot dry matter ratio, total dry matter, and phosphorus use, acquisition, and internal utilization efficiencies. The existence of variability among genotypes was verified for all evaluated characteristics, except for chlorophyll. Genotypes A-16, A-29, A-50, A-52, and Trinity were classified as efficient and responsive in the phosphorus-restricted solution and are promising for breeding studies.

ABSTRACT In equatorial Brazil, the association of Burkitt lymphoma and Epstein–Barr virus manifests at high rates. Here, we report, for the first time, amplifications of aurora kinase genes (AURKA/B) in a patient with a history of periodontal abscess and the presence of a remaining nodule, diagnosed with Burkitt lymphoma and Epstein–Barr virus, and /HIV positive. The patient was a 38-year-old man who presented with a 2-week-old severe jaw pain and a 3-day-old severe bilateral headache. He had a history of human papilloma virus. Interphase FISH analysis showed AURKA and AURKB amplification. The patient’s condition worsened, progressing to death a month after the initial care. Changes in the MYCC and AURKA pathways are directly associated with genomic instability. Thus, MYCC rearrangements and higher expression of AURKA/B may be associated with therapy resistance, highlighting the importance of AURKA/B evaluation in Burkitt lymphoma.

ABSTRACT The planting of unconventional vegetables has increased in Brazil. This is mainly due to the demand of nutritionally rich foods grown in sustainable crops. In this scenario, ora-pro-nobis stands out, as, although being part of the meal of large part of the Brazilian population, it has been cultivated despite the lack of scientific knowledge. Thus, this study aimed to adjust a leaf area estimation model for ora-pro-nobis, using the measurements of the leaves. For the model adjustment and validation, 4000 leaves were collected in four different genotypes, being 1000 in each of them. The regression models were adjusted using 2000 independent and random observations, using 500 leaves per genotype. Thus, the observed leaf area was studied as a linear function of the dimensions of the leaf blade: length (L), width (W) and product (LW). The remaining 2000 observations, also 500 per separate genotype, were used only in the statistical validation study. The adjusted allometric model based on the product (LW) proved to be precise and accurate for estimating the leaf area of ora-pro-nobis, being applicable to any of the four genotypes analyzed regardless of the leaf size: L A ^ L W = 0.9294 + 0.6815 x L W.

RESUMO O plantio de hortaliças não convencionais tem ganhado espaço no cenário nacional, o que se relaciona, principalmente, com a procura por alimentos nutricionalmente ricos advindos de cultivos sustentáveis. Neste cenário, destaca-se o ora-pro-nobis, que embora presente na mesa de muitos brasileiros, tem sido cultivado frente a escassez de conhecimento científico sobre a espécie. Assim, objetivou-se ajustar um modelo de estimação de área foliar (AF) em ora-pro-nobis, usando medidas de suas folhas. Para o ajuste dos modelos e validação do selecionado coletou-se 4000 folhas em quatro genótipos distintos, sendo 1000 em cada um deles. Os modelos de regressão foram ajustados a partir de 2000 observações independes e aleatórias, utilizando-se 500 folhas por genótipo. Deste modo, a área foliar observada foi estudada como função linear das dimensões do limbo foliar: comprimento (C), largura (L) e do produto (CL). As demais 2000 observações, também 500 por genótipo em separado, foram utilizadas apenas no estudo de validação estatística. O modelo alométrico ajustado baseado no produto (CL) mostrou-se preciso e acurado para a estimação da área foliar em ora-pro-nobis, sendo aplicável a qualquer um dos quatro genótipos analisados independentemente do tamanho de suas folhas: A F ^ C L = 0,9294 + 0,6815 x C L.

ABSTRACT There has long been a discussion about the effects of soil management on its structure. Since changes can occur due to management and time of use, more accurate assessments can be achieved if carried out in long-term experiments. This study investigated the long-term effects of soil management on the physical quality of a Cerrado Oxisol (Latossolo Vermelho), focusing on microstructural changes. Micromorphology and computed tomography techniques were used to assess the soil's microstructure. The study compared areas under long-term and different soil management practices, including disc plowing, no-tillage, and disc harrow+subsoiler. A native Cerrado area was considered as the reference. Micromorphology revealed some changes in the pedological features of soil aggregates, but the granular structure showed good resistance even after two decades of use and management. It also indicated a decrease in larger pores and an increase in the surface soil layer micropores for the disc plowing and no-tillage treatments. These results were consistent with traditional laboratory evaluations of soil porosity. Computed tomography was limited due to increased soil bulk density in the cultivated treatments, but it showed potential for assessing soil porosity and pore connectivity. We concluded that micromorphology effectively identifies microstructural changes in Oxisols with small and strong granular structures, and the granular soil aggregates displayed resilience even after long-term management. The micromorphometric evaluation corroborates with traditional methods and suggests loss of pores associated with the disc harrow+subsoiler treatment.

Abstract This article carried out the first scientometric and spatial analysis of Brazilian scientific production on Antarctic soils and permafrost, based on all publications available from the Scopus and Web of Science databases. Information on co-authorship, citation, research topics, and sampling sites was used to understand the social and theoretical structure as well as the spatial dynamics of this research field in Brazil over the last 25 years. We highlight that Brazil is presently, the main country to study the soils and permafrost of Maritime Antarctica, in addition to having an international robust and prolific production, with high impact on the literature, and widely distributed throughout the studied region. It was also possible to identify potential future international partners, new research locations and strategic research themes.

ABSTRACT Large amounts of nitrogen (N) fertilizers applied to maize cropping systems support high yields but cause adverse environmental impacts. The development of cultivars with higher N use efficiency is essential to maintain sustainable production. Thus, the present study aimed to select popcorn inbred lines efficient and responsive to N fertilization expressing high popping expansion. Fifty-one popcorn inbred lines from different origins were evaluated in the field under low and high N availability, arranged in a randomized complete block design with three replications. The two main traits of economic interest in the crop were evaluated: grain yield (GY) and popping expansion (PE). A joint analysis of variance was performed and a scatter plot was generated to classify the inbred lines regarding the response to the N use, focusing on GY. For PE, a Scott-Knott grouping of means was conducted. Within the panel of evaluated popcorn inbred lines, it was possible to identify sources of favorable alleles for nitrogen use efficiency and popcorn expansion, highlighting the inbred lines L205, L206, L217, and L395. These genotypes emerge as potential parents to be included in mating blocks for the development of hybrids and/or breeding populations with high nitrogen use efficiency and popping expansion.

Abstract The steady-state is a situation of little variability of species dominance and total biomass over time. Maintenance of cyanobacteria are often observed in tropical and eutrophic ecosystems and can cause imbalances in aquatic ecosystem. Bayeasian networks allow the construction of simpls models that summarizes a large amount of variables and can predict the probability of occurrence of a given event. Studies considering Bayeasian networks built from environmental data to predict the occurrence of steady-state in aquatic ecosystems are scarce. This study aims to propose a Bayeasian network model to assess the occurrence, composition and duration of cyanobacteria steady-state in a tropical and eutrophic ecosystem. It was hypothesized long lasting steady-state events, composed by filamentous cyanobacteria species and directly influenced by eutrophication and drought. Our model showed steady-state lasting between 3 and 17 weeks with the monodominance or co-dominance of filamentous species, mainly Raphidiopsis raciborskii and Planktothrix agardhii. These evens occurred frequently under drought and high turbidity, however higher nutrients concentrations did not increase the probability steady-state occurrence or longer duration. The proposed model appears as a tool to assess the effects of future warming on steady-state occurrence and it can be a useful to more traditional process-based models for reservoirs.

Abstract The objective of this work was to evaluate the temperament of Canchim calves using different methods, to compare these methods, and to determine the most suitable for commercial use. The temperament of 1,831 calves was evaluated at 15 days after weaning by visually analyzing movement, tension, breathing, vocalizing, and kicking. Measurements were taken at 10 and 20 s after the calf entered the scale. The reactivity score was determined electronically, and flight speed was measured after the calf left the scale. The results of the principal component analysis showed that the first component explained 40.27% of total variation. Positive correlations were found for tension at 10 and 20 s, movement at 10 and 20 s, and reactivity score, with correlation coefficients ranging from 0.60 to 0.88. Temperament and reactivity scores presented moderate correlations of 0.25 and 0.35, respectively, with flight speed. However, kicking had no correlation with any variable. No differences were observed for reactivity measured at 10 or 20 s. The visual evaluations of movement and tension or of reactivity through an electronic device can be used for temperament evaluation of Canchim calves.

Resumo O objetivo deste trabalho foi avaliar o temperamento de bezerros da raça Canchim por meio de diferentes métodos, comparar estes métodos e determinar o mais adequado para uso comercial. O temperamento de 1.831 bezerros foi avaliado 15 dias após a desmama, tendo-se analisado visualmente deslocamento, tensão, respiração, vocalização e coice. As medidas foram feitas aos 10 e 20 s após o bezerro entrar na balança. A reatividade foi determinada eletronicamente, e a velocidade de saída foi medida após o bezerro sair da balança. O resultado da análise de componentes principais indicou que o primeiro componente explicou 40,27% da variação total. Foram verificadas correlações positivas para tensão aos 10 e 20 s, deslocamento aos 10 e 20 s, e reatividade, com coeficientes de correlação de 0,60 a 0,88. Os escores de temperamento e reatividade apresentaram correlação moderada de 0,25 e 0,35, respectivamente, com velocidade de saída. No entanto, coice não se correlacionou com nenhuma variável. Não foi observada nenhuma diferença para reatividade medida aos 10 ou 20 s. As avaliações visuais de deslocamento e tensão ou da reatividade por dispositivo eletrônico podem ser utilizadas na avaliação de temperamento de bezerros Canchim.

ABSTRACT Objective: to analyze childcare and follow-up of children exposed to or notified with congenital syphilis in Primary Health Care. Method: a descriptive study carried out in Fortaleza, Ceará, whose population was made up of children exposed to syphilis or notified with congenital syphilis in 2017 and 2018. The data were collected from notification forms and the children's medical records. Sociodemographic variables of the mother and childcare were analyzed. For this purpose, the Statistical Package for the Social Sciences (SPSS), version 22, was used. Results: a total of 715 children took part in the study. The mothers' age varied from 14 to 42 years old, 436 (61%) had Complete Elementary School, 276 (38.6%) had a steady or occasional partner, 97 (13.6%) had a paid job and 23 (3.2%) used drugs. A total of 712 (99.6%) attended prenatal care and 134 (18.7%) were treated for syphilis. In relation to the children, 50 (7.0%) attended only one childcare consultation and a considerable loss was observed in follow-up over the months. Ten (1.4%) completed all eight consultations recommended by the Ministry of Health. No child underwent the Venereal Disease Research Laboratory at one, three, six, 12 and 18 months. Conclusion: childcare and follow-up of children exposed to syphilis or notified with congenital syphilis do not meet the guidelines recommended by the Ministry of Health. There is a significant follow-up loss among the children.

RESUMEN Objetivo: analizar la puericultura y el seguimiento de niños expuestos a sífilis o notificados con sífilis congénita en Atención Primaria de la Salud. Método: estudio descriptivo realizado en Fortaleza, Ceará, cuya población estuvo conformada por niños expuestos a sífilis o notificados con sífilis congénita en 2017 y 2018. Los datos se recolectaron de los formularios de notificación y de las historias clínicas de los niños. Se analizaron variables sociodemográficas de las madres y de la puericultura de los niños. Para tal fin se utilizó el Statistical Package for the Social Sciences (SPSS), versión 22. Resultados: un total de 15 niños participaron en el estudio. La edad de las madres varió entre 14 y 42 años, 436 (61%) tenían escuela primaria completa como nivel de estudio máximo, 276 (38,6%) tenían pareja estable o eventual, 97 (13,6%) poseían alguna actividad remunerada y 23 (3,2%) consumían drogas. Un total de 712 (99,6%) acudió a las consultas prenatales y 134 (18,7%) recibieron tratamiento para la sífilis. En relación con los niños, 50 (7,0%) solo acudieron a una consulta de puericultura y se observó una considerable pérdida en el seguimiento a lo largo de los meses. Diez (1,4%) completaron las ocho consultas recomendadas por el Ministerio de Salud y ningún niño se sometió al Venereal Disease Research Laboratory de uno, tres, seis, 12 y 18 meses. Conclusión: la puericultura y el seguimiento de niños expuestos a sífilis o notificados con sífilis congénita no cumplen con las directrices recomendadas por el Ministerio de Salud; además, se registra una importante pérdida en seguimiento de los niños.

RESUMO Objetivo: analisar a puericultura e o seguimento de crianças expostas ou notificadas com sífilis congênita na atenção primária em saúde. Método: estudo descritivo realizado em Fortaleza, Ceará cuja população foi composta por crianças expostas à sífilis ou notificadas com a sífilis congênita nos anos de 2017 e 2018. Os dados foram coletados nas fichas de notificação e nos prontuários das crianças. Foram analisadas variáveis sociodemográficas da mãe e da puericultura da criança. Para isso, utilizou-se o programa Statistical Package for the Social Sciences (SPSS), versão 22. Resultados: participaram do estudo 715 crianças. A idade das mães variou de 14 a 42 anos, tinham até o ensino fundamental completo 436 (61%), parceiro fixo ou eventual 276 (38,6%), atividade remunerada 97 (13,6%) e fazia uso de drogas 23 (3,2%). Frequentaram o pré-natal 712 (99,6%) e foram tratadas para sífilis, 134 (18,7%). Em relação às crianças, 50 (7,0%) receberam somente uma consulta de puericultura e observa-se perda considerável no seguimento ao longo dos meses. Dez (1,4%) completaram o quantitativo de oito consultas recomendado pelo Ministério da Saúde. Nenhuma criança fez o Venereal Disease Research Laboratory de um, três, seis, 12 e 18 meses. Conclusão: a puericultura e o seguimento de crianças expostas à sífilis ou notificadas com a sífilis congênita não atendem às diretrizes recomendadas pelo Ministério da Saúde. Há importante perda de seguimento das crianças.

ABSTRACT This research studied the environmental impact of the UASB/anaerobic biofilter system (anaerobic sludge blanket reactor — UASB/ABF) + floating-type constructed wetland (FCW) + vertical flow constructed wetland — microbial fuel cell (FVCW-MFC) + mixed filter with reactive support (MFRS), applied for pilot-scale remediation of urban effluents on a university campus. Scenarios for proposed changes to the settings of the wastewater treatment plant (WTP) were made (Scenarios 2 and 3). The Scenario 1 system was operated in pulses, with the application of 2.9 m3 of university campus effluent per week. Energy required for pumping in the pilot scale unit (Scenario 1) and for potential application with runoff flow (Scenario 2) were inventoried, considering materials for construction and processing, especially with the control of pollutant load in liquid and atmospheric effluents. The SimaPro 8.0.4 software was used, with a functional unit of 2.9 m3 week-1 of effluent and a reference flow of 20 years. The results showed a contribution of 84.8% (in single score — Pt) for the system's construction materials, as well as 15.2% for the operation of the Scenario 2 system, without the use of electricity for pumping. Scenario 3, on the other hand, showed that replacing fiberglass tanks with fiber cement tanks could help reduce environmental impacts during the construction phase of the system by up to 58.6% in terms of energy use and up to 80% in emissions of carcinogenic pollutants.

RESUMO Nesta pesquisa, foi estudado o impacto ambiental do sistema UASB/Biofiltro Anaeróbio (reator anaeróbio de manta de lodo — UASB/BFA) + wetland construído do tipo floating (WCF) + wetland construído de fluxo vertical-célula de combustível microbiana (WCFV-CCM) + filtro misto com suporte reativo (FLR), aplicado para remediação em escala piloto de efluentes urbanos em um campus universitário. Foram feitos cenários de propostas de mudanças das configurações da estação de tratamento de efluente (ETE) (Cenários 2 e 3). O sistema do Cenário 1 foi operado em pulsos, com aplicação de 2,9 m3 de efluente de campus universitário semanalmente. A energia necessária para o bombeamento na unidade em escala piloto (Cenário 1) e para a potencial aplicação com fluxo por escoamento (Cenário 2) foi inventariada, considerando materiais de construção e processamento, especialmente com o controle de carga poluente nos efluentes líquidos e atmosféricos. O software SimaPro 8.0.4 foi utilizado, tendo como unidade funcional 2,9 m3 semana-1 de efluente e fluxo de referência de 20 anos. Os resultados demonstraram que os materiais da construção do sistema contribuíram com 84,8% (em pontuação única — Pt), e a operação do sistema do Cenário 2 contribuiu com 15,2%, sem o uso de energia elétrica para o bombeamento. Já o Cenário 3 mostrou que a substituição dos tanques de fibra de vidro por tanques de fibrocimento poderia ajudar a reduzir os impactos ambientais na fase de construção do sistema em até 58,6% em termos de uso de energia e até 80% nas emissões de poluentes carcinogênicos.

Resumen La tendencia en el consumo de alimentos funcionales, con pocas calorías y con propie dades biológicamente activas, ha ido en aumento. El consumo de raíces tuberosas de yacón se adapta a este concepto por los altos niveles de fructooligosacáridos, lo que le confiere propiedades nutracéuticas. Sin embargo, estas propiedades pueden modularse mediante el manejo de la fertilización en el cultivo de esta planta. Así, nuestro estudio tiene como objetivo evaluar diferentes dosis de fertilización potásica en las características fisico químicas de las raíces de yacón. El diseño experimental utilizado fue de bloques al azar, con 4 repeticiones y 5 tratamientos: cuatro dosis de fertilización potásica (50%; 100%; 150%; 200%) del valor de referencia, correspondiente a 178,7 kg.ha-1; 357,4 kg.ha-1; 536,1 kg.ha-1; 714,8 kg.ha-1 de cloruro de potasio - (KCl), y un testigo (suelo sin fertilizar). Las carac terísticas químicas evaluadas fueron pH, acidez total titulable, sólidos solubles, conduc tividad, turbidez, porcentaje de humedad y cenizas. El perfil de textura se elaboró anali zando la tenacidad, la adhesividad, la cohesión, el índice de masticabilidad, la elasticidad y la pegajosidad. La fertilización con potasio mejoró las características químicas (mayores niveles de sólidos solubles y menor acidez) y las características físicas (menor dureza, masticabilidad, cohesión y adherencia) de las raíces tuberosas de yacón, aportando mayor calidad al producto final.

Abstract The already marked tendency for functional food consumption, low in calories, and with biologically active properties, has been increasing. In this scenario, yacon tuberous roots, with high levels of nutraceutical fructooligosaccharides, gain importance. However, these nutraceutical properties depend on fertilization management. Thus, our study aims to evaluate different doses of potassium fertilization on the physicochemical characteristics of yacon roots. The experimental design consisted of randomized blocks, with 4 replications and 5 treatments: four doses of potassium fertilization (50%; 100%; 150%; 200%) of the reference value, corresponding to 178.7 kg.ha-1; 357.4 kg.ha-1; 536.1 kg.ha-1; 714.8 kg.ha-1 of potassium chloride - (KCl), and a control (soil without fertilization). The chemical features evaluated were pH, total titratable acidity, soluble solids, conductivity, turbidity, moisture and ashes. The texture profile was analyzed through toughness, adhesiveness, cohesiveness, chewability index, elasticity, and gooeyness. Most of the variables were influenced by potassium soil fertilization. Only turbidity, conductivity and gumminess showed no response to the applied doses, not fitting the tested models. Potassium fertilization improved both chemical (higher levels of soluble solids and less acidity) and physical characteristics (less hardness, chewability, cohesiveness, and adhesion) of yacon tuberous roots, bringing greater quality to the final product.