Sete Lagoas Research Articles

Assessment of sorghum genotypes for silage: nutritional value

The objective of this study was to determine the agronomic characteristics, chemical composition and in situ degradability of different sorghum genotypes. The experiment was conducted at the National Maize and Sorghum Research Center – Sete Lagoas, MG. For agronomic and nutritional characteristics, a randomized block design was used, and for in situ degradability, a split-plot design was applied. Genotypes 13F2006, BRS655 and Volumax showed lower dry matter productivity compared to 12F02006 and 12F03033. Genotype BRS655 had the lowest levels of neutral detergent-insoluble fiber (NDF), acid detergent-insoluble fiber (ADF) and lignin. Furthermore, no difference was found for potential degradability (PD), indigestible fraction (IF), and effective degradability (ED) at 2; 5 and 8% hour-1 DM among the studied materials. Genotypes 12F03033 and 12F02006 combine higher productivity and nutritional quality.

Modeling the Impact of Groundwater Pumping on Karst Geotechnical Risks in Sete Lagoas (MG), Brazil

Modeling the Impact of Groundwater Pumping on Karst Geotechnical Risks in Sete Lagoas (MG), Brazil

Inoculation with Bacillus megaterium CNPMS B119 and Bacillus subtilis CNPMS B2084 improve P-acquisition and maize yield in Brazil.

Phosphorus (P) is a critical nutrient for plant growth, yet its uptake is often hindered by soil factors like clay minerals and metal oxides such as aluminum (Al), iron (Fe), and calcium (Ca), which bind P and limit its availability. Phosphate-solubilizing bacteria (PSB) have the unique ability to convert insoluble P into a soluble form, thereby fostering plant growth. This study aimed to assess the efficacy of inoculation of Bacillus megaterium B119 (rhizospheric) and B. subtilis B2084 (endophytic) via seed treatment in enhancing maize yield, grain P content, and enzyme activities across two distinct soil types in field conditions. Additionally, we investigated various mechanisms contributing to plant growth promotion, compatibility with commercial inoculants, and the maize root adhesion profile of these strains. During five crop seasons in two experimental areas in Brazil, Sete Lagoas-MG and Santo Antônio de Goiás-GO, single inoculations with either B119 or B2084 were implemented in three seasons, while a co-inoculation with both strains was applied in two seasons. All treatments received P fertilizer according to plot recommendations, except for control. Both the Bacillus strains exhibited plant growth-promoting properties relevant to P dynamics, including phosphate solubilization and mineralization, production of indole-3-acetic acid (IAA)-like molecules, siderophores, exopolysaccharides (EPS), biofilms, and phosphatases, with no antagonism observed with Azospirillum and Bradyrizhobium. Strain B2084 displayed superior maize root adhesion compared to B119. In field trials, single inoculations with either B119 or B2084 resulted in increased maize grain yield, with relative average productivities of 22 and 16% in Sete Lagoas and 6 and 3% in Santo Antônio de Goiás, respectively. Co-inoculation proved more effective, with an average yield increase of 24% in Sete Lagoas and 11% in Santo Antônio de Goiás compared to the non-inoculated control. Across all seasons, accumulated grain P content correlated with yield, and soil P availability in the rhizosphere increased after co-inoculation in Santo Antônio de Goiás. These findings complement previous research efforts and have led to the validation and registration of the first Brazilian inoculant formulated with Bacillus strains for maize, effectively enhancing and P grain content.

What is the potential of sugarcane borer in reducing sorghum fitness and grain production?

AbstractPest attack is an important biotic threat to sorghum productivity, and one of the main insect pests of grain sorghum is sugarcane borer (SCB) Diatraea saccharalis. Despite the importance of this insect species, little is known about the relationship between SCB infestation and reduction in sorghum grain yield, as well as on the gain threshold and economic injury level for decision making of pest control. This study evaluated the influence of SCB infestation on plant performance and grain production in three commercial grain sorghum hybrids. Hybrids AG1090, BRS 373, and DKB 590 were planted in three crop seasons in Sete Lagoas, Brazil, and six treatments were assessed in the experiments, consisting of three grain sorghum hybrids with and without the insecticide chlorantraniliprole at 52.5 g a.i. ha−1 under SCB natural infestation. The parameters evaluated on sorghum plants were the length of tunnels, plant height, length and weight of panicles, stem borer injury, and grain yield. The infestation of SCB was higher when sorghum plants were not treated with insecticide, resulting in lower productivity. The use of insecticide increased plant height, reduced tunnel length, and increased panicle length and weight. Hybrids only affected panicle weight. The hybrid that presented the highest panicle weight when using the insecticide was AG 1090. Hybrids AG 1090 and DKB 590 showed reduced grain production with increasing gallery length, whereas BRS 373 did not show a significant correlation, which may suggest a certain level of tolerance to SCB attack. This is the first study that determines the gain threshold and economic injury level and that effectively shows how much grain yield is lost by SCB attack in grain sorghum hybrids.

Organic-walled microfossils from the Ediacaran Sete Lagoas Formation, Bambuí Group, Southeast Brazil: taxonomic and biostratigraphic analyses

Abstract This work presents a detailed taxonomic study on organic-walled microfossils from the Ediacaran Sete Lagoas Formation (Bambuí Group) at the Barreiro section in the Januária area of the São Francisco basin, Brazil. Seven species are described, including Siphonophycus robustum (Schopf, 1968), Ghoshia januarensis new species, Leiosphaeridia crassa (Naumova, 1949), Leiosphaeridia jacutica (Timofeev, 1966), Leiosphaeridia minutissima (Naumova, 1949), Leiosphaeridia tenuissima Eisenack, 1958, and Germinosphaera bispinosa Mikhailova, 1986. These taxa are recovered for the first time in the Sete Lagoas Formation. They occur abundantly in the lower portion of the studied section, but only Ghoshia januarensis is present in the upper part of the studied section, probably due to environmental or taphonomic changes. Leiosphaeridia species, particularly Leiosphaeridia minutissima, dominate the organic-walled microfossil assemblage. Although most taxa described here have long stratigraphic ranges, they are consistent with a terminal Ediacaran age as inferred from detrital zircon data and tubular fossils (e.g., Cloudina and Corumbella) from the Sete Lagoas Formation. UUID: http://zoobank.org/7f92b900-0176-4da6-93a3-fd51edb22cbf

Are Land Use and Cover Changes and Socioeconomic Factors Associated with the Occurrence of Dengue Fever? A Case Study in Minas Gerais State, Brazil

Several studies have already demonstrated the relationship between the loss of natural habitats and the incidence of diseases caused by vectors, such as dengue, which is an acute fever disease that is considered a serious public health problem. The aim of the present study was to investigate the relationship between the number of dengue cases and land use and cover changes (LUCC) and socioeconomic and climatic factors by municipality, using the state of Minas Gerais as a case study. For this, secondary data obtained from openly available sources were used. Natural vegetation cover data were obtained from the MAPBiomas platform and dengue occurrence data from the Ministry of Health, in addition to eight socioeconomic parameters from the Brazilian Institute for Geography and Statistics and precipitation data from the Brazilian Agricultural Research Corporation (EMBRAPA, Sete Lagoas, Minas Gerais). Between 2015 and 2019, 1,255,731 cases of dengue were recorded throughout the state of Minas Gerais, ranging from 0 to 227 per thousand inhabitants between municipalities. The occurrence of dengue was distributed throughout all regions of Minas Gerais and was associated with LUCC and socioeconomic factors. In general, municipalities with a net loss of natural vegetation, predominantly located in the Cerrado biome, had the highest number of dengue cases in the studied period. Additionally, the occurrence of dengue was associated to three socioeconomic parameters: population density, human development index (both positively), and Gini inequality index (negatively). These results indicate that, contrary to expectations, municipalities with better social conditions had more dengue cases. Our study indicates that natural vegetation is, directly or indirectly, involved in the ecosystem service of dengue control, despite the occurrence of this disease being affected by multiple factors that interact in a complex way. Thus, policies towards reducing deforestation must be complemented by a continuous investment in public health policies and a reduction in social inequalities to efficiently control dengue fever.

Description of vaccination coverage and hesitancy obtained by epidemiological survey of children born in 2017-2018, in Belo Horizonte and Sete Lagoas, Minas Gerais, Brazil.

To describe vaccination coverage and hesitation for the basic children's schedule in Belo Horizonte and Sete Lagoas, Minas Gerais state, Brazil. Population-based epidemiological surveys performed from 2020 to 2022, which estimated vaccine coverage by type of immunobiological product and full schedule (valid and ministered doses), according to socioeconomic strata; and reasons for vaccination hesitancy. Overall coverage with valid doses and vaccination hesitancy for at least one vaccine were, respectively, 50.2% (95%CI 44.1;56.2) and 1.6% (95%CI 0.9;2.7), in Belo Horizonte (n = 1,866), and 64.9% (95%CI 56.9;72.1) and 1.0% (95%CI 0.3;2.8), in Sete Lagoas (n = 451), with differences between socioeconomic strata. Fear of severe reactions was the main reason for vaccination hesitancy. Coverage was identified as being below recommended levels for most vaccines. Disinformation should be combated in order to avoid vaccination hesitancy. There is a pressing need to recover coverages, considering public health service access and socioeconomic disparities. Vaccination coverage of children up to 4 years old was 50.2% in Belo Horizonte, and 64.9% in Sete Lagoas. Fear of severe reactions and believing that vaccination against eradicated diseases is unnecessary were the main reasons for vaccination hesitancy. Recovery of high vaccination coverage among children, considering public health service access conditions and socioeconomic inequities. Acting on reasons for hesitancy that can assist in targeting actions. The multifactorial context of vaccination hesitancy demands the development of health education strategies to raise awareness about child immunization.

Technical Feasibility of Sorghum Biomass for Briquettes Production

Vegetable biomass has been widely used for bioenergy generation, including sorghum, which has been the object of research for presenting high biomass productivity in the field in a short period of time and its in natura form is an option in sugar and energy plants during the off-season. The use of raw biomass has a number of disadvantages and its densification, through the production of briquettes, improves its energy and physical-mechanical characteristics. The objective of this study was to characterize the in natura biomass and briquettes of two hybrids of biomass sorghum: the commercially used BRS 716 and CMSXS 7016 still in test phase. The cultivation of the two hybrids was carried out at the experimental station of Embrapa Milho e Sorgo, located in the municipality of Sete Lagoas, in Minas Gerais, Brazil, in the 2016/2017 crop, with conventional cultural management for sorghum. The values found for the two hybrids of sorghum biomass are quite satisfactory compared to the values found in the literature for forest and agricultural species that are normally used for energy purposes, except for the ash content, being a viable alternative for energy production. The in natura biomass of hybrid CMSXS 7016 presents similar characteristics to the commercial hybrid BRS 716, and can be used commercially energetic applications. The briquettes of sorghum hybrids biomass are technically feasible for energetic generation, with energy and physical-mechanical characteristics superior to the biomass in natura, with apparent and energy density about 7-8 times higher.

Overexploitation assessment in an urban karst aquifer: The case of Sete Lagoas (MG), Brazil

Overexploitation of groundwater in urban karst aquifers can lead to negative consequences such as land subsidence, depletion of springs and lakes, and water pollution. It can also have indirect effects such as environmental, socio-economic, and political instability. In the municipality of Sete Lagoas, Brazil, the long-term effects of extensive groundwater extraction have been observed and studied over the years. This paper analyzes the response of the karst aquifer to urban, industrial, and climatological changes that may have contributed to changes in the aquifer over the last four decades. The results show that groundwater extraction has exceeded the average aquifer recharge since the year 2000. From the 1980s, the number of wells has steadily increased due to unplanned urban development, resulting in higher demand for groundwater. In the 2010s, pumping from tubular wells (7.39 × 107 m3/yr) exceeded the maximum recharge capacity of the aquifer (7.33 × 107 m3/yr). These wells are mainly concentrated in two areas: the central urban zone and the industrial sector. As a result, kilometer-long cones of depression have formed, changing the aquifer from confined to unconfined within these regions. According to the census data, about 67% of the wells remain unidentified. The average annual recharge to the aquifer is estimated to be 5.68 × 107 m3/yr, which accounts for 12% of the average annual rainfall in the region. Climatological trends indicate an incipient decrease in precipitation and an increase in temperature, suggesting a potential decrease in future aquifer recharge. In addition, only 17% of the area has high infiltration rates ranging from 35% to 75%. The current situation in Sete Lagoas is one of overexploitation of groundwater resources, which could be mitigated by localized reduction of groundwater consumption and implementation of effective management strategies to increase aquifer recharge.

SIMPLE STRUCTURES AND COMPLEX STORIES: POTENTIAL MICROBIALLY INDUCED SEDIMENTARY STRUCTURES IN THE EDIACARAN SERRA DE SANTA HELENA FORMATION, BAMBUÍ GROUP, EASTERN BRAZIL

ABSTRACT Microbially induced sedimentary structures (MISS) are abundant in Ediacaran and lower Cambrian successions. However, the relationship between MISS distribution and facies has not been thoroughly explored in Ediacaran–Cambrian successions in South America. This study documents the occurrence of MISS and other potential biogenic structures from the late Ediacaran Serra de Santa Helena Formation in the Bambuí Group of eastern Brazil. This unit overlies the Cloudina-bearing Sete Lagoas Formation and is a mixed carbonate-siliciclastic succession devoid of macroscopic body fossils. Potential microbial structures include wrinkled structures such as “elephant-skin” and Kinneyia-like textures, as well as pustular structures and abundant positive epirelief discoidal structures. Another putative biogenic structure is a mm-wide meandering groove resembling a simple locomotion trail of a small vagile benthic metazoan. Microbial surface textures (i.e., “elephant skin” and Kinneyia-type wrinkles) were mainly observed in heterolithic deposits, usually at the interface between sandstone and siltstone/shale. On the other hand, discs show a facies-independent distribution, observed in heterolithic as well as carbonate and marl deposits. Petrographic analyses of these discs suggest that they have complex origins and some of them may be diagenetic structures. Thus, while facies may have strongly controlled the preservation of MISS-related structures and textures in the Serra de Santa Helena Formation, their abundance and diversity in tidal flat deposits indicate the wide distribution of matgrounds in these shallow marine paleoenvironments. Also, we demonstrate how detailed description and classification of simple features, such as discoidal structures, is an important task for paleoenvironmental reconstruction of marine ecosystems at the Ediacaran–Cambrian transition when the microbially bounded substrates played important roles in the dynamics of coastal environments.

Horizontal and vertical compartmentalization in the fissure and karstic aquifers of the Lagoa Santa Karst Environmental Protection Area and surroundings, Minas Gerais, Brazil

The study area comprises the Lagoa Santa Karst Environmental Protection Area (EPA) and its surroundings in the metropolitan region of Belo Horizonte. The complex and fragile karstic system of the Sete Lagoas Formation is the main local aquifer and an important reservoir of groundwater for human supply. Based on multidisciplinary studies, a refinement of the Hydrogeological Model of Paula (2019) was made. The study area was expanded to northwest and vertical and horizontal compartmentalization of the aquifers were proposed. The horizontal compartmentalization of the karstic aquifer was based on hydrogeological, hydrodynamic and hydrochemical aspects, where three more karstified compartments were defined. In vertical compartmentalization of the karstic and fissure aquifers, fractures (water inflows), lithological descriptions, cover width and hydraulic conductivity of wells were considered. In the limestones, the more karstified portion extends down to 30 m deep and the crystalline basement acts as an aquifuge at depths greater than 60 m. Six hydrogeologic units were proposed: Granular Aquifer (covers), Aquiclude (pelites of Serra de Santa Helena Formation), Karstic and Fissured-Karstic Aquifer (carbonates of Sete Lagoas Formation), and Fissure Aquifer and Aquifuge (crystalline basement of Belo Horizonte complex).

Effects of maize genotypes, nitrogen rates and sources in yield, nutritional status, and fumonisins incidence.

The maize yield, nutritional status, and grain fumonisins concentration were evaluated in different genotypes, doses, and nitrogen sources (N) in two years and three locations. Two experiments were carried out in each area and year in an experimental design of a subdivided plot with four replications. One experiment involved a 4x2 factorial treatment: four nitrogen (N) doses (0, 80, 160, and 240 kg ha-1) in coverage and having urea as a source of N and two genotypes. Another experiment involved a 4x2 factorial treatment: four N sources: urea, urea covered with polymer, ammonium nitrate, and ammonium nitrate + urea (UAN), at a dose of 160 kg ha-1, in two genotypes. The genotype generally influenced maize yield more than N doses and sources, mainly due to the bushy stunt/corn stunt tolerance of AG7098 PRO2 and AG8677 PRO2. The N doses linearly increased the N leaf content. However, the N sources did not affect the N leaf content. The N doses and sources had no significant effect on the content of fumonisins, which was affected only by the genotypes in Sete Lagoas in 2016 (N doses experiment) and 2017 (N sources experiment). The hybrids, P3630H and AG8677PRO2 (Sete Lagoas, 2016, N doses experiment and 2017, N sources experiment, respectively) exceeded the Brazilian legislation for Maximum Tolerance Limit for fumonisins in corn grains, which is 5,000 µg kg-1. The best result was obtained with AG7098 PRO2, with yields (above 10,000 kg ha-1) and fumonisins consistently below 5,000 µg kg-1. Therefore, the selection of corn hybrids is a strategy to reduce the occurrence of fumonisins in the grains.

Organic chemistry manuscript in pandemic times

In the 1990s and 2000s, several countries underwent important and significant changes in their universities. Likewise, in Brazil, due to the implementation of several government programs, there was an expansion of higher education and made possible a greater access to graduation. At the beginning of 2020, the world was threatened by COVID-19, several restrictive measures were implemented by government and private entities to contain the spread of the disease. In this way, Brazilian educational institutions were forced to temporarily suspend their in-person activities in order to promote social distancing. They soon found themselves in the challenge of implementing teaching methodological changes to continue the activities, in an emergency and remote way, since the outbreak of the disease did not stop within months and there was no prediction of when it would occur. This study aims to evaluate the performance of students at the Federal University of São João del-Rei at the Sete Lagoas campus in the discipline of Organic Chemistry, in the Food Engineering, Agronomic Engineering, Forestry Engineering and Interdisciplinary Biosystems courses in the two semesters of 2018 with 223 students and during the two semesters of the first year of emergency remote teaching (2020) with 337 students, drawing a parallel between them in order to raise the impacts of remote teaching for the discipline of Organic Chemistry.

Identification of filamentous fungi, assessment of extraneous matter and physicochemical analysis of artisanal and industrialized açaí cream

Açaí (Euterpe oleracea and E. precatoria) tree produces berries that are industrialized especially as desserts, such as ice creams, creams, and açai pulp. The processing according to Good Manufacturing Practices (GMP) is fundamental to obtain safe foods for consumption. This work aimed to evaluate the quality of açaí cream marketed in Sete Lagoas, Minas Gerais, Brazil, concerning the presence of fungi and extraneous matter, as well as to evaluate certain physicochemical parameters. It was analysed 21 samples of açaí cream (10 artisanal and 11 industrialized). All 21 samples had acceptable physicochemical quality standards. However, regarding mycological analyses, 23.8% of the samples presented filamentous fungi and 100% presented yeast count. The genera of the predominant filamentous fungi were: Cladosporium spp. (93.9%), Penicillium spp. (1.7%), Rhizopus spp. (2.6%), Paecilomyces spp. (0.9%) and Mucor spp. (0.9%). A total of 57% of the samples presented extraneous matter and the vegetal tissues that represent a health risk were the main material found, therefore, there is a need for adjustments in terms of good processing practices.

Professional Master’s Program in Biotechnology and Innovation Management: The Triple Helix in movement and knowledge generation

This paper analyses evidence of innovation in the joint work of a company, a university and government in creating a professional Master’s degree program in Biotechnology and Innovation Management at the Centro Universitário de Sete Lagoas, Minas Gerais, Brazil. It presents a new perspective by combining two fields of knowledge: biotechnology and innovation management. The conceptual scheme of Triple Helix spaces is still not well analyzed from an empirical viewpoint. This paper identifies the development of knowledge, consensus and innovation spaces through an examination of this professional Master’s course. A qualitative approach was used for the conducting of 20 semi-structured interviews with representatives of the Triple Helix: two directors of Embrapa, a Brazilian agriculture and livestock research company; the President of FAPEMIG, the Minas Gerais Research Support Foundation; nine teachers; and eight students. In addition, data were analyzed from the databases of CAPES (Coordination for the Improvement of Higher Education Personnel). The results show that the proximity between the knowledge areas of biotechnology and innovation management strengthened this new program, created only 7 years ago, which has already impacted socio-economic regional development.

Melanaphis sorghi (Theobald, 1904) (Hemiptera: Aphididae), an invasive sorghum pest in the American continent, is a host of Aphidius platensis (Brèthes, 1913) (Hymenoptera: Braconidae: Aphidiinae) in Brazil

Melanaphis sorghi (Theobald, 1904) is an invasive species recently introduced in the American continent and has been causing great losses in the sorghum crop. In surveys carried out in the cities of Uberlândia and Sete Lagoas, state of Minas Gerais, Brazil, during the year 2021, mummified specimens of M. sorghi were collected on sorghum plants, from which the parasitoid Aphidius platensis (Brèthes, 1913) (Hymenoptera: Braconidae: Aphidiinae) and the hyperparasitoids Syrphophagus sp. and Pachyneuron sp. emerged. This is the first record of A. platensis parasitizing M. sorghi in Brazil.

The sulfur isotopic consequence of seawater sulfate distillation preserved in the Neoproterozoic Sete Lagoas post-glacial carbonate, eastern Brazil

Since the report of tubular structures interpreted as Cloudina from the Neoproterozoic Sete Lagoas Formation (SLF) in the Bambuí basin of eastern Brazil, this stratigraphic unit has become a focus of numerous geochemical, palaeomagnetic, geochronological and sequence stratigraphic studies. Geochemical data from the SLF have been used to infer palaeoenvironmental conditions in the Bambuí basin and to study the 13 C enrichment reported in this and overlying units. To further address depositional environments of the SLF, we present high-resolution δ 13 C and δ 34 S data from the SLF in the Januária and Sete Lagoas regions. We report the presence of superheavy pyrite with δ 34 S value greater than carbonate-associated sulfate (CAS) and observe a decrease in CAS abundance coupled with a δ 34 S change from c. +20 to near +50‰. These data are interpreted as evidence for distillation of sulfate through CAS and pyrite removal from the epeiric Bambuí basin. These changes are qualitatively consistent with quantitative simulations of isotopic distillation over a period of c. 10 myr of a seawater sulfate reservoir comparable with modern concentration. Considering that Neoproterozoic seawater sulfate concentrations were probably much lower than in modern oceans, the distillation time interval was probably much shorter than 10 myr. Supplementary material : MATLAB/Octave code to replicate Figs 11, 12 and 13 is available at https://doi.org/10.6084/m9.figshare.c.5845089 Thematic collection: This article is part of the Sulfur in the Earth system collection available at: https://www.lyellcollection.org/cc/sulfur-in-the-earth-system

Accumulation of biomass and lignocellulosic compounds in photoperiod-sensitive biomass sorghum genotypes

Biomass sorghum [Sorghum bicolor (L.) Moench] has unique characteristics that allow its use as a feedstock for bioenergy production. This study aimed to analyse the growth and accumulation of biomass and lignocellulosic compounds in photoperiod-sensitive biomass sorghum genotypes and to evaluate interactions with the environment at different phenological stages using the absolute and relative crop growth rates. Four photoperiod-sensitive biomass sorghum genotypes were evaluated over two crop years and two sites in the state of Minas Gerais, Brazil. It was mensured agronomic and technological traits. The mean performance of the genotypes were adjusted using logistic and polynomial regression models, and the absolute (CGR) and relative (RCGR) growth rates were subsequently estimated. The environment (site and/or crop year) influenced the trait expression regarding plant height, cellulose and lignin accumulation. The genotypes at Sete Lagoas site matured earlier, with a greater plant height and greater accumulation of biomass and lignocellulosic compounds, except lignin, over a shorter period compared to Lavras site. Across genotypes and environments, CGRs with a peak inflection at approximately 90 days after sowing (DAS) were observed for growth and biomass production, but a decrease starting at 30 DAS was observed in the CGRs for lignocellulosic compounds and in the RCGRs for growth, biomass production and lignocellulosic compounds. In addition, at both sites, the crop could be harvested earlier, at approximately 120 DAS in Sete Lagoas and 150 DAS in Lavras, given the high biomass production, dry matter percentage above 30% and high content of lignocellulosic compounds.

Impacto do transporte nas emissões de CO2 do concreto: um estudo de caso em Rio Branco/Brasil

Abstract Due to the scarcity of crystalline massifs in the north of Brazil, concrete producers have been using crushed stone and cement from suppliers located hundreds of kilometers away. In this case, CO2 emissions related to material transportation for concrete production may become significant. Thus, this study aims to analyze the influence of the transportation of the materials in CO2 emissions of ready-mix concrete production in Rio Branco (Acre). Concrete compositions were obtained from a local concrete producer. Brazilian methods of dosage were not applicable due to the high fineness of the regional sand available; the mix designs were adjusted empirically. Two types of cement (CP V-ARI and CP IV) were considered to create the studied scenarios. Transportation distances of the raw materials (cement and aggregates) ranged from 20 km (local sand supplier) to 3,592 km (cement supplier from Sete Lagoas, MG). CO2 emissions to produce concrete (fck of 25 MPa, cement consumption of 426 kg/m3) ranged from 208 kgCO2/m3 to 573 kgCO2/m3. Transportation was responsible for up to 20% of total emissions. The emissions in this study are considerably higher than the national data of concrete production available in the Construction Environmental Performance Information System (Sidac) due to the higher cement consumption and higher transportation distances. Although cement consumption in Acre represents less than 1% of Brazilian consumption, the results reveal the impact of transportation distances in CO2 emissions of concrete in cities that deal with local scarcity.

A 6-year field monitoring of fall armyworm, Spodoptera frugiperda, in transgenic Bt maize in Brazil

A 6-year field monitoring study was designed to compare the presence of fall armyworm Spodoptera frugiperda (J. E. Smith), leaf injury, its parasitoids, 100 seed weight, and seed yield of Bt maize hybrids approved for commercialization in the Brazilian market. Field trials were planted in two municipalities, divided into two periods, from 2011 to 2014 (period I), and due to the approval of different Bt hybrids, from 2015 to 2016 (period II). Treatments were Bt, non-Bt maize and all non-Bt maize sprayed with insecticide methomyl. Six Bt-maize hybrids were planted, expressing the following proteins: Cry1Ab, Cry1F, Cry1A.105 (Cry1Ab +Cry1Ac +Cry1F), Cry2Ab2a and Vip3. In 2015 and 2016 Bt Powercore was planted due to its commercial approval. The number of S. frugiperda larvae for most Bt hybrids was lower than on non-Bt hybrids, except for Fórmula TL and Herculex in period II, in both municipalities. In period I, Bt hybrids VT, VT 2 and Viptera showed almost no injury on their leaves, despite the high number of fall armyworm larvae found in plants. Different parasitoids emerged from larvae from Bt and non Bt hybrids: Archytas sp., Campoletis sp., Chelonus sp., Eiphosoma sp. and Ophion luteus. The average 100 seed weight was higher in municipality from Sete Lagoas for all Bt hybrids, non-Bt hybrids and non-Bt hybrids sprayed with methomyl, when compared to Nova Porteirinha during period I. Fórmula TL, non-Bt Fórmula TL sprayed with methomyl, and non-Bt Fórmula TL showed the lowest seed yield in both municipalities and periods.