ABSTRACT Background: The Amazon rainforest plays an essential role in sheltering global biodiversity and providing essential ecosystem services. However, the region has been threatened by increased rates of deforestation and degradation, which is often reported as the failure of the Brazilian conservation policy that could affect the image of agriculture Brazilian products abroad. In this sense, here we aimed to evaluate the foreign environmental perception of the region using data from social medias, to assess which are the main terms related to the region, how their importance varies over time and whether this perception tends to be more negative or positive. For this, we used data from posts made on Twitter® involving the term “Amazon rainforest” over 18 weeks using a data mining process. From these posts, we extracted the text, which went through steps of cleaning and organization, as well as crossing with additional databases (such as the sentiment dictionary). From the final data set, we first evaluated which are the main terms present in these posts and how their importance varied in the evaluated period. Next, we assess whether the terms cited are mainly negative or positive and how this sentiment varied over the monitoring period. Results: We found that the main terms are related to the environmental context such as “carbon”, “deforestation” and “fire” and that there is a relationship between their importance and the occurrence of fires in the region, which is positive with a temporal lag. In addition, we also found that the posts are, on average, composed of 68.47% of negative terms and that this sentiment predominates throughout the entire time series, being higher during the fire peaks in the region. Conclusion: Our results indicate that the environmental perception of the region presented in the posts in Twitter® is mainly negative, due to the degradation and fires observed over the last few years. We also discuss limitations of the approach and establish perspectives for future work.

Abstract Banana tree bacterial wilt is caused by the Ralstonia solanacearum Moko ecotype. These strains vary in their symptom progression in banana, and are classified as typical Moko variants (phylotype IIA and IIB strains from across Central and South America), Bugtok variant (Philippines), and Sergipe facies (the states of Sergipe and Alagoas, Brazil). This study used comparative genomic and phylogenomic approaches to identify a correlation between the symptom progression of the Moko ecotypes based on the analysis of 23 available genomes. Average nucleotide identity and in silico DNA-DNA hybridization revealed a high correlation (>96% and >78%, respectively) between the genomes of Moko variants. Pan-genome analysis identified 21.3% of inheritable regions between representatives of the typical Moko and Sergipe facies variants, which could be traced to an abundance of exclusive homolog clusters. Moko ecotype genomes shared 1,951 orthologous genes, but representatives with typical symptoms did not display unique orthologues. Moreover, Bugtok disease and Sergipe facies genomes did not share any unique genes, suggesting convergent evolution to a shared symptom progression. Overall, genomic and phylogenomic analyses were insufficient to differentiate the Moko variants based on symptom progression.

Abstract Banana vascular wilt or Moko is a disease caused by Ralstonia solanacearum. This study aimed to sequence, assemble, annotate, and compare the genomes of R. solanacearum Moko ecotypes of different sequevar strains from Brazil. Average nucleotide identity analyses demonstrated a high correlation (> 96%) between the genome sequences of strains CCRMRs277 (sequevar IIA-24), CCRMRs287 (IIB-4), CCRMRs304 (IIA-24), and CCRMRsB7 (IIB-25), which were grouped into phylotypes IIA and IIB. The number of coding sequences present in chromosomes and megaplasmids varied from 3,070 to 3,521 and 1,669 to 1,750, respectively. Pangenome analysis identified 3,378 clusters in the chromosomes, of which 2,604 were shared by all four analyzed genomes and 2,580 were single copies. In megaplasmids, 1,834 clusters were identified, of which 1,005 were shared by all four genomes and 992 were identified as single copies. Strains CCRMRsB7 and CCRMRs287 differed from the others by having unique clusters in both their chromosomes and megaplasmids, and CCRMRsB7 possessed the largest genome among all Moko ecotype strains sequenced to date. Therefore, the genomic information obtained in this study provides a theoretical basis for the identification, characterization, and phylogenetic analysis of R. solanacearum Moko ecotypes.

RESUMO Objetivo: Verificar a influência das alterações climáticas sobre o broncoespasmo induzido por exercício, nos períodos chuvoso e seco de uma região do semiárido brasileiro. Métodos: Foram submetidos à avaliação do broncoespasmo em esteira ergométrica, em ambiente externo, nos períodos chuvoso e seco, 82 adolescentes, com idades de 15 a 18 anos. Foram avaliadas as variáveis antropométricas, a maturação sexual e o volume expiratório forçado no primeiro segundo. Para comparação da temperatura e umidade, queda do volume expiratório forçado no primeiro segundo (%) e frequência do broncoespasmo entre os períodos, foram utilizados o teste t de Student independente, o teste de Wilcoxon e o teste de McNemar, respectivamente. O nível de significância adotado foi p<0,05. Resultados: A média de idade foi 15,65±0,82 anos. A temperatura, a umidade e a queda do volume expiratório forçado no primeiro segundo (%) diferiram entre os períodos, com valores de temperatura e umidade maiores no período chuvoso (29,6ºC±0,1 e 70,8%±0,6 versus 28,5ºC±0,2 e 48,4%±0,6; p<0,05). A queda do volume expiratório forçado no primeiro segundo (%) foi maior no período seco (9,43%±9,97 versus 12,94%±15,65; p<0,05), e não foi encontrada diferença da frequência do broncoespasmo entre os períodos. Conclusão: O período seco influenciou negativamente no volume expiratório forçado no primeiro segundo de adolescentes, observando maior percentual de queda dessa variável nesse período. De acordo com os achados, propõe-se uma maior gravidade do broncoespasmo induzido por exercício em condições de baixa umidade.

ABSTRACT Objective: To examine the impact of climate variability on the occurrence of exercise-induced bronchospasm in the rainy and dry seasons of a Brazilian semi-arid region. Methods: This sample comprised 82 adolescents aged 15 to 18 years, who were submitted to exercise-induced bronchospasm assessment on a treadmill and outdoors, during the rainy and the dry season. Anthropometric variables, sexual maturity and forced expiratory volume in the first second were analyzed. Air temperature and humidity, decline in forced expiratory volume in the first second (%) and frequency of bronchospasm were compared between seasons using the independent Student’s t test, the Wilcoxon and McNemar tests, respectively. The level of significance was set at p<0.05. Results: The mean age was 15.65±0.82 years. Air temperature, air humidity and decline in forced expiratory volume in the first second (%) differed between seasons, with higher air temperature and humidity in the rainy season (29.6ºC±0.1 and 70.8%±0.6 versus 28.5ºC±0.2 and 48.5%±0.6; p<0.05). The decline in forced expiratory volume in the first second (%) was greater in the dry season (9.43%±9.97 versus 12.94%±15.65; p<0.05). The frequency of bronchospasm did not differ between seasons. Conclusion: The dry season had a negative impact on forced expiratory volume in the first second in adolescents, with greater decrease detected during this period. Findings of this study suggested bronchospasm tends to be more severe under low humidity conditions.

abstract background: the recovery of areas impacted by mining activities is a major challenge and requires knowledge of how the biological and biochemical processes of the soil as well as the establishment of plant species are affected by mining residue. in this work, the influence of deposition of iron mining mud and tailings on soil biochemical attributes and the initial development of tree seedlings was studied in a simulated event in the greenhouse. pots (n = 27) with natural soil (2.0 kg) received deposition (280 ml) of iron mining mud or tailings and by three-month was cultivated with urochloa decumbens. at the end of this period, part of the pots was sampled and the soil biochemical activities were evaluated. then tree seedlings (schinus terebinthifolius and eremanthus incanus) were planted and cultivated for a year, when then shoot (sdw) and roots (rdw) dry weight were evaluated. results: deposition of iron mining mud and tailings did not affect microbial biomass carbon or basal soil respiration, however both conditions reduced (p < 0.05) β-glucosidase activities by up to 30%, and the easy extractable glomalin by about 19%. in addition, the mud deposition reduced (p < 0.05) the sdw and rdw of s. terebinthifolius by about 21% and 24%, respectively. nevertheless, uruchloa decumbens and eremanthus incanus had no variation in dry weight production between treatments, so they have good ability to grow settle in soil affected by mining residue. conclusion: this study shows that the sequential planting of u. decumbens and e. incanus can be an alternative for use in environments with deposition of iron mining tailings.

Resumo Este estudo teve como objetivo estimar a força propulsora da braçada(FPB) em jovens nadadores do estilo livre e propor uma equação para estimar a força propulsora, considerando variáveis antropométricas e a maturação. Setenta e seis nadadores competitivos [meninos: n = 53; idade = 13,58 ± 1,79; meninas: n = 23; idade = 12,98 ± 1,79] participaram deste estudo. Foram avaliados: altura, massa magra, estatura sentada, comprimento da perna, envergadura, dobra cutânea do tríceps, área muscular do braço (AMB) e maturação. A força propulsiva da braçada foi medida pelo teste de nado atado. Uma regressão linear múltipla (modelo concorrente) foi usada para desenvolver a equação usando as variáveis AMB, envergadura e maturação. O método de Bland – Altman foi utilizado para comparar os valores encontrados entre FPB e força propulsiva estimada (FPE). Houve correlação significativa entre as variáveis FPB e AMB (R² = 0,12; p <0,01), envergadura (R² = 0,21; p <0,01) e maturação (R² = 0,20; p <0,01) para meninos, enquanto os valores das meninas foram: AMB (R² = 0,07; p = 0,20), envergadura (R² = 0,50; p <0,01) e maturação (R² = 0,44; p <0,01). Duas equações lineares foram estabelecidas para predizer a FPB em meninos e meninas. A análise de Bland-Altman mostrou concordância entre FPB e FPE. Em conclusão, a equação é uma ferramenta valiosa para monitorar o treinamento e ajudar a melhorar o desempenho do nadador.

Abstract This study aimed to estimate the propulsive force of the arm (PFA) in young freestyle swimmers and propose an equation to estimate propulsive force, considering anthropometric variables and maturity offset. Seventy-six competitive swimmers [boys: n= 53; age= 13.58 ± 1.79; girls: n= 23; age= 12.98 ± 1.79] participated in this study. Height, lean mass, sitting height, leg length, arm span, triceps skinfold, arm muscle area (AMA), and maturity offset were assessed. The propulsive force of the arm was measured by the tethered swim test. A multiple linear regression (concurrent model) was used to develop the equation using the variables AMA, arm span, and maturity offset. The Bland–Altman method was used to compare the values found between PFA and propulsive force–estimated (PFE). There was a significant correlation between the variables PFA and AMA (R²=0.12; p<0.01), arm span (R²=0.21; p<0.01), and maturity offset (R²=0.20; p<0.01) for boys, whilst in girls theses values were: AMA (R²=0.07;p=0.20), arm span (R²=0.50;p<0.01), and maturity offset (R²=0.44;p<0.01). Two linear equations were established to predict the PFA in boys and girls Bland-Altman analysis showed an agreement between PFA and PFE. In conclusion, the equation is a valuable tool to monitor training and help improve swimmer performance.

ABSTRACT Background: Intrathecal injection of voltage-sensitive calcium channel blocker peptide toxins exerts analgesic effect in several animal models of pain. Upon intrathecal administration, recombinant Phα1β exerts the same analgesic effects as the those of the native toxin. However, from a clinical perspective, the intrathecal administration limits the use of anesthetic drugs in patients. Therefore, this study aimed to investigate the possible antinociceptive effect of intravenous recombinant Phα1β in rat models of neuropathic pain, as well as its side effects on motor, cardiac (heart rate and blood pressure), and biochemical parameters. Methods: Male Wistar rats and male Balb-C mice were used in this study. Giotto Biotech® synthesized the recombinant version of Phα1β using Escherichia coli expression. In rats, neuropathic pain was induced by chronic constriction of the sciatic nerve and paclitaxel-induced acute and chronic pain. Mechanical sensitivity was evaluated using von Frey filaments. A radiotelemeter transmitter (TA11PA-C10; Data Sciences, St. Paul, MN, USA) was placed on the left carotid of mice for investigation of cardiovascular side effects. Locomotor activity data were evaluated using the open-field paradigm, and serum CKMB, TGO, TGP, LDH, lactate, creatinine, and urea levels were examined. Results: Intravenous administration of recombinant Phα1β toxin induced analgesia for up to 4 h, with ED50 of 0.02 (0.01-0.03) mg/kg, and reached the maximal effect (Emax = 100% antinociception) at a dose of 0.2 mg/kg. No significant changes were observed in any of the evaluated motor, cardiac or biochemical parameters. Conclusion: Our data suggest that intravenous administration of recombinant Phα1β may be feasible for drug-induced analgesia, without causing any severe side effects.

Resumo: O objetivo deste trabalho foi avaliar o efeito do uso de escória de siderurgia como corretivo da acidez do solo e de fungos micorrízicos associados à adubação fosfatada em plantas de milho. O trabalho foi conduzido em casa de vegetação, tendo-se utilizado vasos com 3 kg de Latossolo Vermelho distrófico, em arranjo fatorial 4x5x2, com quatro tratamentos corretivos da acidez (C1, correção com calcário dolomítico na dosagem de 4 Mg ha-1; C2, correção com escória de siderurgia de aciaria na dosagem de 4 Mg ha-1; C3, correção com a mistura 1:1 de 2 Mg ha-1 de calcário dolomítico e 2 Mg ha-1 de escória; e C4, controle, sem correção de pH), cinco doses de fósforo (0, 42, 95, 213 e 480 mg dm-3), e presença ou ausência de dois fungos micorrízicos arbusculares (Rhizophagus clarus e Gigaspora margarita), com cinco repetições. A escória foi eficiente em corrigir o pH do solo e fornecer Ca e Mg para as plantas; portanto, pode substituir o calcário. A inoculação com R. clarus e G. margarita, associada às doses de 42, 95 e 213 mg dm-3 de P, promoveu melhoras no desenvolvimento de plantas de milho após 45 dias, tendo resultado em maiores altura, diâmetro do colo, área foliar e matéria seca das raízes e da parte aérea das plantas.

Abstract: The objective of this work was to evaluate the effect of the use of steel slag as a soil acidity corrective and of mycorrhizal fungi associated with phosphate fertilization on corn plants. The study was performed in a greenhouse, using 3-kg pots with a Typic Haplorthox, in a 4x5x2 factorial arrangement, with four acidity correction treatments (C1, correction with dolomitic limestone at a dose of 4 Mg ha-1; C2, correction with steel slag at a dose of 4 Mg ha-1; C3, correction with a 1:1 mixture of 2 Mg ha-1 dolomitic limestone and 2 Mg ha-1 steel slag; and C4, control, without pH correction), five phosphorus doses (0, 42, 95, 213, and 480 mg dm-3), and the presence or absence of two arbuscular mycorrhizal fungi (Rhizophagus clarus and Gigaspora margarita), with five replicates. Steel slag was efficient in correcting soil pH and providing Ca and Mg for the plants; therefore, it could replace limestone. The inoculation with R. clarus and G. margarita, associated with P doses of 42, 95, and 213 mg dm-3, improved the development of corn plants after 45 days, resulting in greater plant height, stem diameter, leaf area, and shoot and root dry matter.

ABSTRACT This research was conducted to investigate the effect of live and inactive sugarcane yeast on beef cattle voluntary intake, apparent digestibility of nutrients, ruminal pH, volatile fatty acids (VFA) concentrations, and ruminal ammonia. Five rumen-cannulated Nellore heifers were distributed in a 5×5 Latin square design, with five experimental periods of 15 days, with seven days for adaptation to the additives and the remaining days for data records and sampling. Total mixed ration (TMR) was composed by corn silage (20%) and concentrate (80%) based on corn and soybean meal. Five treatments were evaluated: without additive use (negative control; NC); chemical buffer addition – 0.71% in concentrate DM of sodium bicarbonate and 0.18% of magnesium oxide (positive control, PC); 10 g/day live yeast (LY); 15 g/day of inactive yeast (IY15); and 30 g/day of inactive yeast (IY30). Sugarcane yeasts were directly infused in rumen immediately after morning and afternoon feed supply. Feed additives did not affect voluntary intake, nutrient digestibility, and sorting behavior of animals. However, heifers from all treatments presented preferential intake of fibrous fraction of diet, especially those from NC and IY15. Nitrogen balance, VFA concentrations, and blood parameters were not influenced as well. Sodium bicarbonate and magnesium oxide led to greater ruminal pH than yeast, and IY15 presented greater pH than IY30. Ruminal ammonia was increased by the use of additives. Active and inactive yeasts are not recommended as feed additives for bovines fed diets with 80% of concentrate since it allows animals to select fibrous particles from TMR, and no representative gain in ruminal parameters and digestibilities are guaranteed.

Resumo O estudo avaliou a ocorrência de focos de calor nos remanescentes da Mata Atlântica no estado do Rio de Janeiro, sob o aspecto climático. As informações obtidas da base de dados BDQueimadas, do período de junho de 1998 a dezembro de 2015, sofreram estatística descritiva, exploratória e paramétrica. As maiores ocorrências de focos de calor foram registradas nos meses de agosto, setembro e outubro e, os anos com os maiores registros foram nos ciclos 2010/2011 (16,06%) e 2014/2015 (41, 24%), ambos somaram 57,30% da série temporal, referente a La Niña e El Niño nas categorias forte e fraco. O teste paramétrico mostrou uma repetição dos meses de abril e junho nos anos avaliados na série temporal de focos de calor. As regiões de Governo Centro-Sul Fluminense e Médio Paraíba registraram os maiores registros de focos de calor, segundo a avaliação espacial. Nossos resultados demonstram que o acesso a uma base gratuita de dados permite a prevenção de danos causados pelas queimadas e incêndios. Com a evolução dos sensores de temperatura e de algoritmos de tratamento de dados, será possível diferenciar os focos de calor que representam incêndios e queimadas daqueles que indicam, por exemplo, atividade de indústrias.

Abstract The study evaluated the occurrence of fire focus in the remnants of the Atlantic Forest in the state of Rio de Janeiro, from a climatic perspective. The data obtained from the database BDQueimadas, from June 1998 to December 2015, underwent descriptive, exploratory and parametric statistics. The highest temperature records were identified in the 2010/2011 (16.06%) and 2014/2015 (41% and 24%) cycles. The total percentage (57, 30%) of the time series indicated strong and weak categories, as La Niña and El Niño. The parametric test showed that August, September and October had the highest temperature records, but a similar thermal pattern was found during April and June, in the same years. As for the regions, the highest temperature recorded, according to the spatial evaluation of the fire focus distribution, was for Central-South Fluminense and Médio Paraíba. Our results demonstrate that through access to a relatively simple database it is possible to obtain objective information that can be used for the prevention of damage caused by fires. With the expected evolution of thermal sensors and data-processing algorithms, it is very likely that we can skillfully discriminate fire focus related to fires from those indicating, for example, industry activity or relevant specificities.

Resumo: O objetivo deste trabalho foi identificar e quantificar, por meio de modelos de regressão linear múltipla, os fatores de produção que afetam o consumo diário de ração e a conversão alimentar de suínos nas fases de crescimento e terminação, em granjas integradas a uma cooperativa. Foram avaliados os históricos produtivos de 690 lotes, que representavam aproximadamente 363 mil animais alojados entre 2010 e 2013 em 118 granjas vinculadas a uma cooperativa do Estado do Paraná. Foram considerados 44 fatores de produção relacionados a instalações, manejo, sanidade, genética e alimentação. O consumo diário de ração (CDR) foi menor nos lotes oriundos de granjas com árvores nas laterais dos galpões e naqueles formados apenas por fêmeas. Já a conversão alimentar (CA) foi melhor para os lotes provenientes de granjas com árvores nas laterais dos galpões, alojados no verão/outono, oriundos de granjas edificadas em alvenaria e que apresentavam composteira e unidades especializadas produtoras de leitões. Os pesos de entrada e de saída dos lotes influenciaram o CDR, e o peso de entrada e a duração do período de engorda, a CA. Os modelos de regressão linear múltipla possibilitam identificar variáveis de importância e estimar seus efeitos sobre a conversão alimentar e o consumo diário de ração de suínos nas fases de crescimento e terminação.

Abstract: The objective of this work was to identify and quantify, through multiple linear regression models, the factors of production that affect the daily feed intake and feed conversion ratio of pigs in the growing and finishing phases, in farms linked to a company. The production records of 690 batches were evaluated, representing approximately 363 thousand animals housed between 2010 and 2013 in 118 commercial farms linked to a company in the state of Paraná, Brazil. Forty-four factors of production related to facilities, management, health status, genetics, and feeding were considered. Daily feed intake (DFI) was lower in batches from farms that had trees planted on the sides of the barns and in those formed only by females. The feed conversion ratio (FCR) was better in batches from farms with trees on the sides of the barns, housed during summer/fall, originated from farms with barns built of masonry and that had compost bins and specialized units for producing piglets. The initial and final weights of the batches affected DFI, and the initial weight and duration of the growing and finishing phases, the FCR. The multiple linear regression models allow identifying important variables and estimating their effects on FCR and DFI of pigs in the growing and finishing phases.

ResumoObjetivou-se avaliar as características de qualidade da carne de frango de corte tipo caipira em diferentes tempos de jejum alimentar. Aves, machos, da linhagem “pesadão vermelho”, criadas até 85 dias de idade em sistema semiextensivo, foram submetidas aos tempos de zero, três, seis, nove e 12 horas de jejum alimentar. Obteve-se o peso vivo, peso da carcaça, o rendimento de carcaça fria, o peso do trato gastrintestinal das aves. Foram avaliados o pH24h, a luminosidade (L*), o teor de vermelho (a*), o teor de amarelo (b*), a capacidade de retenção de água, a perda de peso por cocção e a força de cisalhamento na carne do peito, da coxa e da sobrecoxa. Menor valor de rendimento de carcaça foi observado no tempo zero hora (74,54%), e o maior (82,43%) às nove horas de jejum alimentar. Maior peso para o trato gastrintestinal (540,8g) foi observado no tempo zero e o menor (229,33g) às 12 horas de jejum alimentar. Não foi observado efeito dos diferentes tempos de jejum alimentar nas características de qualidade da carne das aves. Houve diferença no pH24h, na luminosidade (L*), no teor de vermelho (a*), no teor de amarelo (b*) e na capacidade de retenção de água quando se comparou os cortes da carne do peito, da coxa e da sobrecoxa das aves de corte tipo caipira. Recomendam-se os períodos de jejum de nove ou 12 horas, nos quais houve maior rendimento de carcaça fria.

AbstractIt aimed to evaluate the quality characteristics of the rustic type broiler meat at different times of fasting. Birds, males, Pesadão Vermelho lineage, created up to 85 days old in semiextensivo system, were subject to the zero times, three, six, nine and 12 hours of fasting. This gave the live weight, carcass weight, cold carcass yield, the weight of the gastrointestinal tract of birds. The pH24h were evaluated, lightness (L*), red content (a*), a yellow content (b*), the water holding capacity, cooking loss of weight and shear force in meat breast, thigh and drumstick. Carcass yield lower was observed in the zero hour (74.54%) and the largest (82.43%) to nine hours of fasting. Greater weight to the gastrointestinal tract (540,8g) was observed at time zero and the lowest (229,33g) at 12 hours of fasting. There was no effect of different times of fasting in the quality characteristics of the meat of birds. There was a difference in pH24h, the lightness (L*), red content (a*), yellow content (b*) and water holding capacity when compared the breast meat cuts, thigh and drumstick of the rustic type broiler. Periods of fasting are recommended nine or 12 hours, in which there was higher cold carcass yield.

A estrutura do solo exerce importante influência na sustentabilidade dos ecossistemas e no crescimento de plantas. Os fungos micorrízicos arbusculares (FMAs) constituem um importante grupo funcional da microbiota do solo, atuando diretamente nos processos de agregação, principalmente em agroecossistemas e têm relação direta com a produção e diversidade vegetal. Esses estão amplamente distribuídos no agroecossistemas tropicais e são extremamente importantes para o crescimento de várias espécies vegetais agrícolas. No presente estudo, avaliou-se o efeito da inoculação com Glomus macrocarpum e diferentes sucessões de culturas no crescimento vegetal, na atividade microbiana e na agregação de um Latossolo Vermelho de Cerrado. O estudo foi conduzido em delineamento inteiramente casualizado com arranjo fatorial 4 x 4. Os tratamentos constituíram da combinação entre quatro condições de eliminação e/ou introdução de FMA (NS-NI: não autoclavado-não inoculado; NS-I: não autoclavado-inoculado; S-NI: autoclavado-não inoculado; S-I: autoclavado-inoculado) e quatro sucessões de culturas (Panicum maximum/Panicum maximum; Brachiaria ruziziensis/soja; sorgo/soja; Stylosanthes spp./soja). A inoculação com FMAs favoreceu o crescimento do estilosantes, apresentando aumento de até 91% na produção de massa seca quando inoculado. Nenhumas das gramíneas beneficiaram-se com a introdução de G. macrocarpum. Nós observamos que a inoculação com G. macrocarpum associado aos FMAs indígenas incrementou a biomassa microbiana, atividade da fosfatase ácida, diâmetro médio geométrico e o ponderado. Os resultados indicam os efeitos benéficos da inoculação que reflete na melhoria da estrutura do solo, contribuindo para a sustentabilidade.

Soil structure has major influence on ecosystem sustainability and plant growth. Arbuscular mycorrhizal fungi (AMF) are an important functional group of soil microbiota, acting in the process of aggregation, especially in agroecosystems and related to the production and plant diversity. AMF are widely distributed in tropical agroecosystems and are extremely important for development of many agricultural crops. The present study evaluated the effect of inoculation with Glomus macrocarpum in different crop sequences on plant growth, microbial activity and aggregation of a Cerrado Oxisol. The study was conducted in a completely randomized design in a4 x 4 factorial scheme. Treatments consisted of four conditions of elimination and/or introduction of AMF (NS-NI: non-sterilized and non-inoculated; NS-I: non-sterilized and inoculated; S-NI: sterilized and non-inoculated; andS-I: sterilized and inoculated) and four crop sequences (Panicum maximum/Panicum maximum, Brachiaria ruziziensis/ soybean, sorghum/soybean and Stylosanthes spp./soybean). Inoculation favored growth of Stylosanthes spp. by increasing plant growth in up to 91% when inoculated. None of the grasses benefited from G. macrocarpum introduction. We observed that G. macrocarpum inoculation associated with indigenous AMF increased microbial biomass, phosphatase activity, mean geometric diameter and mean weighted diameter. The results indicated the beneficial effects of inoculation, which reflected in soil structure improvement and, hence, to agroecosystems sustainability.

A busca por substratos alternativos, que possam substituir produtos comerciais na produção de mudas de tomate, é de fundamental importância para a redução dos custos nessa fase inicial da cultura. Objetivou-se, com esta pesquisa, avaliar a qualidade de mudas de tomate industrial IPA 6, produzidas com substratos à base de esterco ovino. O experimento foi conduzido em viveiro da Universidade Federal Rural de Pernambuco, Unidade Acadêmica de Serra Talhada, de 16 de fevereiro a 30 de março de 2012. Utilizou-se o delineamento inteiramente casualizado, com quatro repetições. Os tratamentos avaliados foram: T1 - [substrato comercial]; T2 - [esterco ovino + areia (1:1)]; T3 - [esterco ovino + areia (2:1)]; T4 - [esterco ovino + areia (3:1)]; T5 - [esterco ovino + solo (1:1)]; T6 - [esterco ovino + solo (2:1)]; T7 - [esterco ovino + solo (3:1)]; T8 - [esterco ovino + areia + solo (1:1:1)];T9 - [esterco ovino + areia + solo (2:1:1)]; T10 - [esterco ovino + areia + solo (3:1:1)]. Os indicadores de emergência avaliados foram: percentagem, índice de velocidade e tempo médio de emergência. Analisaram-se as seguintes características de desenvolvimento: número de folhas, altura de plântula, diâmetro de caule, comprimento de raízes, massa da matéria seca da parte aérea e das raízes. O substrato comercial proporcionou melhor vigor de mudas de tomate IPA 6. Por outro lado, o uso do esterco ovino mais solo (2:1), para compor substratos alternativos constituiu-se opção viável para a produção de mudas desse cultivar.

The search for alternative substrat that can replace commercial products in the tomato seedlings production is very important to reduce costs at the first stage of such culture. The present study aimed to evaluate the quality of industrial tomato IPA 6 seedlings produced with alternative substrate of sheep manure. The experiment was carried ou at a plant nursery at the Universidade Federal Rural de Pernambuco, in Serra Talhada, Pernambuco State, Brazil, from February 16 to March 30, 2012. The experimental design was a completely randomized design with four replications. The treatments were: T1 - commercial substrate; T2 - sheep manure + sand (1:1); T3 - sheep manure + sand (2:1); T4 - sheep manure + sand (3:1); T5 - sheep manure + soil (1:1); T6 - sheep manure + soil (2:1); T7 - sheep manure + soil (3:1); T8 - sheep manure + sand + soil (1:1:1); T9 - sheep manure + sand + soil (2:1:1); T10 - sheep manure + sand + soil (3:1:1). The emergence indicators were: percentage, speed index and average time of emergence. Regarding the development characteristics of seedlings were analyzed: leaf number, stem diameter, seedling height, root length, shoot dry matter and root dry matter. The commercial substrate provided better vigor of tomato IPA 6 seedlings. Moreover, the use of soil and sheep manure (2:1) to compose alternative substrates consisted of a viable option for seedlings production of this cultivar.