State Of Tocantins Research Articles

Effects of functional traits on the spatial distribution and hyperdominance of tree species in the Cerrado biome

The ecological influence of functional traits on species persistence as well as on their role over the organization of forest communities in the Brazilian Cerrado biome have not been fully understood yet. In this study, we assessed the effects of six functional groups, characterized by three seed dispersal syndromes (i.e., anemochory, autochory, and zoochory) and three wood density classes (i.e., hardwood, lightwood, and softwood), on tree spatial distribution patterns, habitat occupancy, and ecosystem services (biomass hyper dominance and abundance) provided by a forest community located in the “Parque do Lajeado”, state of Tocantins, Brazil. The similarity among study sites was characterized by applying the tree dominant height approach and the environmental and soil variables as input. The floristic similarity was assessed by applying the Bray-Curtis index. The zoochoric species showed more aggregated spatial pattern at local scale, which indicates that it is more sensitive to environmental gradients than other dispersal syndromes. Meanwhile, hardwood density species were more established in the community, being more persistent to environmental filters. We observed that a small number of species contributed with about 50% of the abundance and biomass of the community, whose functional traits (wood density and dispersal syndrome) indirectly affect the relationship among the community species richness and their ecosystem functions. We observed that the functional traits related to seed dispersal and wood density functional groups resulted in different spatial distribution patterns of those tree species. Therefore, functional traits and environmental factors combined have substantially affected the structure and composition of forest communities at local scale.

To clear or not to clear: Unpacking soy farmers' decision-making on deforestation in Brazil's Cerrado

Agriculture-driven deforestation has come to the top of the environmental policy agenda as one of the main sustainability issues of current food systems. A major case is soy production in Brazil, the largest grower and exporter of what has become the world's crop of choice for animal feed protein. Soy expansion has contributed to the continuous erasure of the Brazilian Cerrado, a highly biodiverse savanna with significant underground carbon storage that plays vital hydrological functions but remains mostly unprotected. Much of the remaining Cerrado vegetation is located within private farms and can be cleared legally; therefore, understanding soy farmers' attitudes regarding deforestation is paramount. Hence, this study explores and analyzes Brazilian soy farmers' perspectives, attitudes, and behavior concerning land-use change. We draw from the literature and semi-structured interviews with 24 soy farmers in Tocantins State, part of an agricultural frontier region called Matopiba. Our findings show how soy-farmer behavior follows primarily an economic rationale unconcerned with environmental sustainability. Farmers have moved to the frontier attracted primarily by cheap land prices and mainly occupied degraded pastures. Still, they have cleared vegetation directly for planting soy and show little restraint. Although chiefly interested in increasing yields, Brazil's soy farmers feel entitled to open new areas whenever they have the economic means and motivation. They may also engage in pre-emptive deforestation for fear of more stringent forthcoming regulations. Such attitudes offer a cautionary note to strategies that hope to conserve the Cerrado through voluntary behavioral change, such as adopting “best practices” or focusing on improving production in already-open areas. We argue that greater regulatory stringency and enforcement are much more promising pathways in the context of excessive permissiveness to deforestation in the Cerrado and actors oriented by profit and by what they are allowed to do. Well-enforced public policies that legally restrict their deforestation rights and protect the remaining areas of Cerrado would offer a royal road, but supply-chain actors, too, may need to become stricter about requesting conversion-free soy. We conclude that, without such actions, soy farmers' attitudes promise a continuation of business as usual toward the Cerrado's end.

Genomic Epidemiology Reveals the Circulation of the Chikungunya Virus East/Central/South African Lineage in Tocantins State, North Brazil.

The chikungunya virus (CHIKV) is a mosquito-borne virus of the family Togaviridae transmitted to humans by Aedes spp. mosquitoes. In Brazil, imported cases have been reported since June 2014 through two independent introductions, one caused by Asian Lineage in Oiapoque, Amapá state, North Region, and another caused by East/Central/South African (ECSA) in Feira de Santana, Bahia state, Northeast Region. Moreover, there is still limited information about the genomic epidemiology of the CHIKV from surveillance studies. The Tocantins state, located in Northern Brazil, reported an increase in the number of CHIKV cases at the end of 2021 and the beginning of 2022. Thus, to better understand the dispersion dynamics of this viral pathogen in the state, we generated 27 near-complete CHIKV genome sequences from four cities, obtained from clinical samples. Our results showed that the newly CHIKV genomes from Tocantins belonged to the ECSA lineage. Phylogenetic reconstruction revealed that Tocantins’ strains formed a single well-supported clade, which appear to be closely related to isolates from the Rio Grande do Norte state (Northeast Brazil) and the Rio de Janeiro state (Southeast Brazil), that experienced an explosive ECSA epidemic between 2016–2019. Mutation analyses showed eleven frequent non-synonymous mutations in the structural and non-structural proteins, indicating the autochthonous transmission of the CHIKV in the state. None of the genomes recovered within the Tocantins samples carry the A226V mutation in the E1 protein associated with increased transmission in A. albopictus. The study presented here highlights the importance of continued genomic surveillance to provide information not only on recording mutations along the viral genome but as a molecular surveillance tool to trace virus spread within the country, to predict events of likely occurrence of new infections, and, as such, contribute to an improved public health service.

Climate changes and land use in farming regions: evidence from Buritirana district (Jalapão gateway), Tocantins state, Brazil: 2004-2018

The following research analyzed the interactions between climate change and land use in the Buritirana district, a farming region located at Jalapão gateway, Tocantins state, Brazil. This relatively small area gathers high-tech soybean production developed in recent years, cattle breeding, small family farming, and none associated producers. The study focused on two groups: on the one hand farmers of the agricultural settlements Sítio and Entre Rios and on the other large soybean producers. The database was obtained by the MapBioma project and the WorldClim collection. The images retrieved were processed to plot geographic illustrations and furthermore to elaborate and interpret linear regression. Such framework intended to provide more evidences about the future perspectives of agricultural production in tropical regions. The results revealed an annual increase of average temperature in the examined region, characterized by a strong expansion of soybean monoculture, between 2013 and 2018. However, based on statistical analysis, evidence of correlating soybean expansion to climate changes in the Buritirana region could not be confirmed. Nevertheless, spread of monoculture and reduction of native flora in the Jalapão region and surroundings should be considered with concern, especially for small rural familiar farmers and for wildlife as well, even after approval of the new Brazilian Forest Code in 2008.

Environmental Changes and the Impact on the Human Infections by Dengue, Chikungunya and Zika Viruses in Northern Brazil, 2010-2019.

Environmental changes are among the main factors that contribute to the emergence or re-emergence of viruses of public health importance. Here, we show the impact of environmental modifications on cases of infections by the dengue, chikungunya and Zika viruses in humans in the state of Tocantins, Brazil, between the years 2010 and 2019. We conducted a descriptive and principal component analysis (PCA) to explore the main trends in environmental modifications and in the cases of human infections caused by these arboviruses in Tocantins. Our analysis demonstrated that the occurrence of El Niño, deforestation in the Cerrado and maximum temperatures had correlations with the cases of infections by the Zika virus between 2014 and 2016. El Niño, followed by La Niña, a gradual increase in precipitation and the maximum temperature observed between 2015 and 2017 were shown to have contributed to the infections by the chikungunya virus. La Niña and precipitation were associated with infections by the dengue virus between 2010 and 2012 and El Niño contributed to the 2019 outbreak observed within the state. By PCA, deforestation, temperatures and El Niño were the most important variables related to cases of dengue in humans. We conclude from this analysis that environmental changes (deforestation and climate change) presented a strong influence on the human infections caused by the dengue, chikungunya and Zika viruses in Tocantins from 2010 to 2019.

Can medical residency keep young specialists in the place where they graduate? Cross-sectional and exploratory study of the first seven years after implementation of medical residency programs in the State of Tocantins, Brazil.

ABSTRACTBACKGROUND:New medical schools and new medical residencies in Brazil, mainly in its interior, were opened under the justification of collaborating towards distribution of these healthcare professionals and specialist doctors across the national territory. However, this proposal did not guarantee that medical practitioners would become established in the place where they graduated and specialized.OBJECTIVE:To calculate, through interviews, how many specialists who graduated in the state of Tocantins stayed there after finishing their medical residency; and to analyze the factors that made them stay or leave the place.DESIGN AND SETTING:Cross-sectional exploratory study conducted at a Brazilian federal public higher education institution.METHODS:All graduates from medical residencies in Tocantins, who graduated between 2013 and 2019, were contacted by telephone and, after obtaining consent, an interview was conducted. The interviews took place between June 2020 and January 2021.RESULTS:The permanence of medical residency graduates in the state increased from 50% in an earlier study to 55.8% in the current study, thus showing a situation of stability. In addition, we detected some reasons for staying or not. In a multivariate analysis, only working in the state capital was related to staying in the state of Tocantins, showing a 5.6 times greater chance.CONCLUSIONS:The percentage of those who remained was just over 50%, even some years after implementation of the first programs. Most specialists remained working for the state health department, with a smaller proportion in municipal health departments, and were concentrated in the state capital.

A checklist of social wasps (Vespidae: Polistinae) from Tocantins state, Brazil

Tocantins state has high biodiversity and a high degree of endemism, nevertheless, there are no studies on the diversity of social wasps. This study introduces a survey of social wasps actively collected using entomological nets and Malaise trap in addition to different light traps in sixteen sites in the Amazon and Cerrado biomes in Tocantins state, Brazil. We sampled a total of 1,013 social wasps distributed in 57 species of 13 genera. Fifty of these species and nine genera represent new distribution records for the state. Some species are not commonly found in collections and lists of species, and Protopolybia picteti (de Saussure, 1854) is newly recorded for Brazil. Such an increase of 714% may indicate that Polistinae richness is probably higher in the studied regions and that the state of Tocantins may well contain several additional (yet unrecorded) social wasp species. More comprehensive studies should be conducted to enhance the knowledge of wasp species in this state, contributing to our understanding of the biodiversity in Northern Brazil.

Primary care: women's health indicators in the state of Tocantins, Brazil

Resumo Introdução Na região norte do Brasil observa-se a maior taxa de incidência e mortalidade por câncer de colo uterino (CCU), uma patologia 100% curável quando diagnosticada precocemente. Objetivo Este estudo visa apresentar uma análise temporo-espacial da adesão ao exame de rastreio do CCU, assim como o número de gestantes acompanhadas por agentes de saúde em domicílio, no estado do Tocantins. Método Os dados para a análise foram obtidos através da plataforma DATASUS, considerando um período de quinze anos (2001 a 2015), e foram organizados em planilhas através do software Excel. Para a avaliação espacial, ferramentas de geoprocessamento foram utilizadas, como o software Quantum GIS, com o intuito de gerar mapas temáticos. Resultados Os resultados revelaram que embora existam programas de prevenção do CCU, a adesão ao exame pelas mulheres no estado é muito inferior ao desejado. Quanto ao acompanhamento domiciliar das gestantes, a maior parte dos munícipios registrou médias acima do esperado. Conclusão Mediante ao estudo nota-se a necessidade de adotar novas medidas para melhorar a adesão ao exame preventivo do CCU, já que empregar apenas campanhas educacionais não está sendo suficientemente efetivo. Em relação ao acompanhamento das gestantes, é necessário avaliar a qualidade e não apenas a quantidade, para que seja possível uma melhor orientação e cuidado.

The tendency of stunting among children under five in the Northern Region of Brazil, according to the Food and Nutrition Surveillance System, 2008-2017

ObjectiveTo analyze the temporal tendency of stunting prevalence among children under five years of age registered in the Food and Nutritional Surveillance System (SISVAN) in the Brazilian Northern Region, from 2008 to 2017. MethodsEcological time-series study with data from SISVAN. The annual variation rate for the prevalence of undernutrition, measured by the presence of stunting (low height-for-age index), was estimated for the Northern Region and for each of its states using the Prais-Winsten regression model with and without variable adjustment for SISVAN coverage to explore the relationship between these variables. ResultsThe Northern Region showed a tendency toward the reduction of chronic child stunting, with an annual variation of -5.30% (95%CI -9.64; -0.77) in the period studied. The states of Acre (-7.19%; 95%CI -12.31; -1.77), Pará (-4.86%; 95%CI -9.44; -0.03), and Tocantins (-6.22%; 95%CI -9.88; -2.41) showed a tendency to reduce the prevalence of stunting, while the other four states showed stability during the period. A strong negative correlation was found between SISVAN coverage and the prevalence of stunting in the states of Acre (beta: -0.725), Amazonas (beta: -0.874), Pará (beta: -0.841), and Tocantins (beta: -0.871), indicating that the increase in system coverage is associated with a reduction of stunting. ConclusionsThere is a tendency toward a reduction in the prevalence of stunting particularly in three states and in the North Region as a whole, from 2008 to 2017. The coverage by the system was associated with a reduction in the prevalence of child stunting in four states.

Predictable Chikungunya Infection Dynamics in Brazil.

Chikungunya virus (CHIKV) was first imported into the Caribbean in 2013 and subsequently spread across the Americas. It has infected millions in the region and Brazil has become the hub of ongoing transmission. Using Seasonal Autoregressive Integrated Moving Average (SARIMA) models trained and validated on Brazilian data from the Ministry of Health’s notifiable diseases information system, we tested the hypothesis that transmission in Brazil had transitioned from sporadic and explosive to become more predictable. Consistency weighted, population standardized kernel density estimates were used to identify municipalities with the most consistent inter-annual transmission rates. Spatial clustering was assessed per calendar month for 2017–2021 inclusive using Moran’s I. SARIMA models were validated on 2020–2021 data and forecasted 106,162 (95%CI 27,303–200,917) serologically confirmed cases and 339,907 (95%CI 35,780–1035,449) total notifications for 2022–2023 inclusive, with >90% of cases in the Northeast and Southeast regions. Comparing forecasts for the first five months of 2022 to the most up-to-date ECDC report (published 2 June 2022) showed remarkable accuracy: the models predicted 92,739 (95%CI 20,685–195,191) case notifications during which the ECDC reported 92,349 case notifications. Hotspots of consistent transmission were identified in the states of Para and Tocantins (North region); Rio Grande do Norte, Paraiba and Pernambuco (Northeast region); and Rio de Janeiro and eastern Minas Gerais (Southeast region). Significant spatial clustering peaked during late summer/early autumn. This analysis highlights how CHIKV transmission in Brazil has transitioned, making it more predictable and thus enabling improved control targeting and site selection for trialing interventions.

Analyzing the impact of agricultural water-demand management on water availability in the Urubu River basin – Tocantins, Brazil

The Urubu River is part of the Formoso River Basin located in Tocantins State in northern Brazil. It is an important agricultural region where irrigation has an important role in rice and soybean crops, cultivated during the rainy and the dry seasons, respectively. The high levels of irrigation associated with below-average precipitation in 2016 and in the following years resulted in a water crisis in the Urubu Basin, with serious consequences to the environment and the economy of the region. This work evaluated the impact of reducing irrigation on environmental flows in the Urubu River Basin using hydrological modeling in WEAP. Irrigation water demand scenarios were simulated and analyzed from July 2018 through June 2019. Results indicated the need to reduce 35% of all water withdrawls in order to avoid the interruption of flow in the Urubu River Basin. This percentage was even greater when only some of the farmers cooperated. The paper emphasized that it is important that all farmers be involved and cooperate to reduce their water withdrawal by any means, including improving their irrigation system efficiency. The water regulator may also motivate water withdrawal reduction by modifying water permits and applying water withdrawal restrictions during the dry season.
 Keywords: hydrological modeling, scenario analysis, water balance.

Palinofácies de folhelhos do devoniano superior da borda oeste da bacia do parnaíba palynofacies of upper devonian shales from the west edge of the parnaíba basin

An outcrop section of rocks from the Upper Devonian, providing plant and animal microfossils that register a time of global post-anoxia and major marine flooding events, was investigated by applying palynofacies techniques and organic geochemistry. The primary purpose of this work is the palynofacies characterization of a Neo-Devonian section of the Parnaíba Basin, belonging to the Pimenteiras Formation. Thirteen outcrop samples were collected in the western edge of the Parnaíba Basin, Tocantins State - Brazil, where a possible contact between the Pimenteiras and Cabeças formations was identified. Through optical/visual analysis of organic content and organic groups (amorphous organic matter - AOM/Palynomorphs/Phytoclasts), as well as their relative abundance, associated with previous total organic carbon (TOC) data, it was possible to individualize four (4) distinct palynofacies throughout the section. The variation in the proportions of marine and continental palynomorphs suggests sea-level fluctuation during deposition, characterizing a transitional environment, varying from the most distal to the most proximal deposition platform. Based on the predominance of palynomorphs and phytoclasts, the kerogen types II and III were recognized, corroborating with the hydrogen and oxygen indexes obtained through pyrolysis data. The predominance of yellow to chestnut colors exhibited by the prasinophyte and acritarch components under ultraviolet light excitation indicates good organic matter preservation and thermal immaturity following the organic geochemistry data.

Hematological, biochemical and histopathological changes in cattle submitted to emergency slaughter

This study aimed to evaluate the effects of stress in bovines submitted to emergency slaughter caused by lengthy transportation to slaughterhouses in the state of Tocantins, Brazil. Blood collections were performed individually during exsanguinations. Tissue samples were obtained after evisceration on the slaughter line. The animals were divided into the Experimental Group (EG), with 19 bovines destined for immediate emergency slaughter, and the Control Group (CG), with 24 bovines slaughtered normally at the abattoir flow. The EG showed lower values of erythrocytes, hemoglobin, hematocrit, platelets, neutrophilia with band neutrophils, and lymphopenia. Hyperalbuminemia, high levels of total proteins, glucose, and creatinine, and lower urea levels were observed in the EG. The globulins were equal between the groups. Histopathology revealed hepatocytes with vacuolated cytoplasm (87.5% of the cases) and liver congestion (83.33%). Interstitial emphysema (95.65%), alveolar emphysema (65.21%), and congestion (52.17%) were observed in the lungs. The kidneys showed congestion (80.95%) and hyaline casts (100%). The spleens showed rarefaction in the white (70%) and red pulp (65%), in addition to hemosiderosis (10%). This suggests that the animals transported over long distances are submitted to severe stress, with water and food deprivation, resulting in hematological and biochemical changes, with histological lesions and serious bruises affecting the musculoskeletal system. There is loss of homeostasis, severe debilitation, with destination for emergency slaughter with the conditional use of meat for consumption.

SER QUILOMBOLA: EXPRESSÕES DE IDENTIDADE QUILOMBOLA CONSTRUÍDAS NA COMUNUNIDADE DONA JUCELINA

The article deals with the identity construction of the Quilombola Dona Juscelina Community, located in the northern region of the state of Tocantins, in the municipality of Muricilândia, based on the psychoanalytical theoretical framework that includes identification as a constituent part of the EU. The article seeks to identify identifying objects that express the quilombola identity in the Dona Juscelina quilombola community, as well as to contribute to the deepening of knowledge related to quilombola identities and traditional peoples in the region. This is a literature review, based on scientific productions about the community. Thus, we found identifying elements that expressed the collective identity of the community such as land, ancestry and the celebration of abolition.

Pesticide residues in the Formoso River: a threat to biodiversity in the Cerrado of the Tocantins State, Brazil

Cerrado biodiversity has been threatened by the increase in agricultural production in the state of Tocantins and the increase in the use of pesticides. This work was carried out in the Formoso do Araguaia region, on the banks of the Formoso River, which is home to about 1,825 indigenous people and is one of the largest indigenous lands in the state of Tocantins, Brazil. The presence of pesticides of the imidazolinone and strobirulin classes was verified, analyzed by UHPLC-MS/MS from April 2018 to February 2019, to assess the impacts of these pesticides on the biodiversity of the study site. After the analyses, five active principles (azoxystrobin, phenamidone, imazethapyr, tricyclazole and trifloxystrobin) were detected in the water matrix, two active principles (azoxystrobin and tricyclazole) in the soil matrix, but no active principle was detected in the sediment matrix. Contamination in the region, where riverine and indigenous people use this water for cultivation, hygiene and food, which is worrying, are exposed to these substances.

Quality of Honey Produced by Four Species Of Stingless Bees in the Central Region of the State of Tocantins

Meliponiculture, the rational breeding of native stingless bees, is considered an excelente sustainable alternative to assist in the pollination process and is an economically viable activity. In the cerrado of Tocantins, the meliponine species that stand out most due to their wide distribution are: Scaptotrigona tubiba, Melipona fasciculata,M. rufiventris and Tetragonisca angustula. The bibliographic collection about these species is still little explored, hence there is a need for research to deepen the existing knowledge in the area. For this reason, the aim of this study was: a) to quantify the honey production of four meliponine species: T. angustula, M. fasciculata, M. rufiventris, and S. tubiba; b) to determine the physicochemical characteristics of the product; c) measure the biological parameters of the colony and d) evaluate the profile and sensory acceptance of honey in the municipalities, Palmas and Miracema, in the Tocantins. The study evaluated the biological parameters of the colony, honey production, and physicochemical analysis. The highest honey production came from the species T. angustula in the two collections for the municipality of Palmas. For Miracema, the species S. tubiba and M. fasciculata were evaluated, respectively. The physicochemical parameters evaluated fit the norms assigned to honey quality control. Results showed that honey from M. fasciculata was the sensory profile that obtained the best average among the characteristics observed in the study. There was a positive and negative correlation between the biological parameters, with a significant difference only between the characters’ height and diameter of the honey pot.

A New Circular Single-Stranded DNA Virus Related with Howler Monkey Associated Porprismacovirus 1 Detected in Children with Acute Gastroenteritis.

Putative replication-associated protein (REP) and capsid-like (CAP) proteins are encoded by circular single-stranded DNA viruses (CRESS DNA), which have been found in samples from most eukaryotic groups. However, the details of these viruses’ life cycles and their significance in diseases have yet to be established. We presented and analyzed two full-length CRESS DNA genomes acquired from two children diagnosed with acute gastroenteritis (GI) in the northeast state of Tocantins, Brazil, using next-generation sequencing and a virus-like filtration approach. Both sequences (named SmaCV3BR08 and SmaCV3BR291) are closely similar to a prior CRESS DNA sequence discovered in the feces of a new world monkey (Alouatta caraya) from the United States in 2009 and termed Howler monkey-associated porprismacovirus 1 (Genbank ID: NC 026317). According to our comparative study, these porprismacovirus genomes deviate by 10% at the nucleotide level. For comparative reasons, the divergence between our sequences (SmaCV3BR08 and SmaCV3BR291) and a porprismacovirus recently identified in a human fecal sample from Peru is 37%. These data suggest that there is a great diversity of porprismacoviruses in South America, perhaps more than two species. In addition, the finding of closely related sequences of porprismacoviruses in humans and native monkeys highlights the zoonotic potential of these viruses.

Temporal trend of mortality and hospitalization for chronic kidney disease in adults from Northern Brazil.

We aimed to evaluate mortality and hospital admissions for chronic kidney disease in young adults according to sex and state in the northern region of Brazil, between 1996 and 2017. A population-based time series study using official data on mortality and hospital admissions due to chronic kidney disease in individuals aged 20 to 49 years old, residents of the northern region of Brazil, in the periods 1996–2017 and to 2008–2017, respectively. Chronic kidney disease was defined according to the International Classification of Diseases, 10th revision (N18).The evolution of mortality from chronic kidney disease decreased by 0.881% per year over the period (1996–2017). In the states of Acre and Amapá, there was a reduction of 5.85% and –5.68% per year, respectively, and in Tocantins, an increase of 4.16% per year. The incidence of hospitalization did not vary between 2008 and 2017. However, 2 states showed an increase in hospitalization rates: Acre (6.08% per year) and Pará (2.83% per year), and 2 states showed a reduction: Amazonas (5.09% per year) and Tocantins (6.23% per year).In general, there was decrease in mortality rate overtime. However, rate of mortality due to chronic kidney disease increased in the state of Tocantins. The evolution of hospitalization due to chronic kidney disease in a population of young adults remained stationary.

Modalities and planting seasons in lettuce cultivation in Gurupi, state of Tocantins (Gurupi-To), Brazil

Lettuce (Lactuca sativa L.) is the main leafy vegetable grown in Brazil. Its productivity and quality are limited by the growing season, the nearby environment and the type of cultivar adopted. The objective of this work was to verify at different times of the year the best planting environment for lettuce cultivation in a semi-humid tropical climate. For this purpose, an experiment was set up in three different seasons (October–November 2014, January–March, May–July 2015). The experimental design was randomized blocks, in a 3 × 3 × 2 factorial arrangement, consisting of three seasons, three cultivars (cvs. Vera®, Tainá® and Rafaela®) and two growing environments (low tunnel with beds protected with mulching consisting of soil protection with plastic fabric covering, and beds without protection or conventional cultivation) and four replicates per treatment. Plant biomass, stem length, head diameter, number of leaves per head and crop productivity were evaluated as response parameters. The results showed that the May–July period favored biomass production, head diameter and productivity. Despite the similarity between varieties, the variety Vera® is more productive in biomass, number of leaves per head, stem length and productivity. The low tunnel planting system with mulching is adequate under the conditions evaluated for lettuce cultivation. This system in the May–July period favors a superior development in the characteristics biomass, head diameter and productivity, if compared to conventional cultivation during the October–November period.

Efficiency of inoculation methods for genotypes selection in corn ear rot disease studies

The identification of resistance of plants to pathogens is crucial for the development of hybrids by breeding programs. To achieve that, it is of great relevance to establish effective inoculation methods for characterizing genotypes with adequate plant resistance levels. Several inoculation methods have been investigated in the search for resistance to corn ear rot disease. However, studies evaluating different corn genotypes cultivated under Neotropical field conditions remain unexplored. Here, we compared three inoculation methods (i.e., aspersion, injectable, and natural) of Fusarium verticillioides in corn ears, and evaluated disease severity and grain yield of 10 corn genotypes. The experiments were conducted in two consecutive experimental corn crop (i.e., 2015 and 2016) seasons located in cities with different environmental temperatures and belonging to different Brazilian states (i.e., Gurupi – Tocantins State, Itumbiara – Goiás State, Planaltina – Brazilian Federal District, and Toledo – Paraná State). We evaluated the mass of 1000 grains and the severity of the disease. Regarding the disease severity, our results showed that the artificial inoculation was more efficient in the regions of Planaltina and Toledo, not affecting grains’ mass in these localities. The severity of disease on the conditions of Toledo was similar for the ten genotypes. However, it was possible to identify two contrasting genotypes since P4285H (low severity) and 32R48YH (medium severity) exhibited significantly more disease symptoms in all other regions. Although the differences regarding the efficiency of inoculation methods are more evident in regions with milder temperatures, the results showed that the characterization of genotypes susceptible to the pathogen is more efficient in regions with higher temperatures.