Caracterização, aptidão agrícola e capacidade de uso de um Argissolo Vermelho-Amarelo Eutrófico abrúptico: Estudo de caso em Itapetinga-BA / Characterization, agricultural aptitude and use capacity of 'Argissolo Vermelho-Amarelo Eutrófico abrúptico: a case study in Itapetinga -BA

No município de Itapetinga,90% das terras são ocupadas com pecuária e os Argissolos são os solos mais comuns. A pequena capacidade protetora das pastagens e também o adensamento dos rebanhos, tem causado severa compactação no solo, que se torna preocupante.Diante disso, os objetivos da pesquisa foram: i) caracterizar morfológica, física e quimicamente um Argissolo Vermelho-Amarelo; ii) indicar a aptidão agrícola e capacidade de uso. Realizou-se a caracterização morfológica do solo e coletaram-se amostras dos horizontes para caracterização física equímica. Fisicamente determinou-se a granulometria e argila dispersa em água (ADA). Quimicamente foram analisados os cátions trocáveis do complexo sortivo (Ca2+, Mg2+Na+, K+, Al3+e H+), pH, carbono, nitrogênio total e fósforo disponível,bem como, óxidos Al2O3e Fe2O3 por ataque sulfúrico. Os sistemas de Avaliação de Aptidão Agrícola das Terras e de Capacidade de Uso foram as metodologias utilizadas para essas classificações. A descrição morfológica e dados analíticos permitiram classificar o solo como Argissolo Vermelho-Amarelo Eutrófico abrúptico. Quanto à aptidão agrícola e capacidade de uso, o solo foi classificado como 1abC e IV E-3, respectivamente. Conclui-se que o uso atual está inadequado, recomendando-sepastagens perenes associadas a práticas conservacionistas que evitem a erosão do solo. O caráter abrúptico, aliado à compactação provocada pela pecuária extensiva, agrava ainda mais a perda da capacidade produtiva desse solo, condição representativa para a microrregião de Itapetinga, onde a maiorparte do seu território é coberto por Argissolos Vermelho-Amarelos Eutróficos, sendo cerca de 41%.(AU)

The livestock agriculture fromItapetinga are in area ofArgissolos. Themanagement of livestock has caused compaction. Thus, the purpose of the study was: i) describe the morphological, Chemical, and physical of the Argissolo Vermelho-Amarelo; ii) classify your agricultural aptitude and use capacity. The morphological characterization was described: depth, color, structure, texture, consistency, and transition. The physical analysis was: texture and clay dispersed in water. The Chemical analysis determined the cations (Ca2+, Mg2+ Na+, K+, Al3+ e H+), pH, carbon, nitrogen and phosphorus. The oxides Al2O3and Fe2O3were determined. The "Sistema de Avaliação de Aptidão Agrícola das Terras" and "Sistema de Capacidade de Uso" were used for classification. The soil was classified with Argissolo Vermelho-Amarelo Eutrófico abrúptico. Your aptitude has been graded as 1abC and IV E-3 to use capacity. Therefore, the use of soil is incorrect, because the perennial pasture with practices against erosion is the correct form of use. The abrupt characterwith compaction by the animals result in losses of the productive capacity of the soil.This is reality of the microregion of Itapetingabecausemost ofthe territory is in area of Argissolos Vermelho-Amarelos Eutróficos, totaling 41% of the total area.(AU)

Dejeto líquido de suínos: efeito no solo e nas perdas de K, Ca e Mg por erosão hídrica / Pig slurry: effect on soil and K, Ca and Mg losses by water erosion

O dejeto de suíno (DLS) é usado como fertilizante cujos nutrientes são perdidos por erosão e contaminam o ambiente se o dejeto é usado inadequadamente. Objetivou-se avaliar o efeito de DLS nosolo e na erosão, num Nitossolo Bruno. Os tratamentos, 0; 50; 100; e 200 m³ ha-1de DLS foram aplicados superficialmente após a semeadura uma vez em cada um dos cinco cultivos, e na palhada do último cultivo, totalizando 0, 250, 500 e 1000 m³ ha-1, na aveia (Avena strigosa), milho (Zea mays), nabo (Raphanus sativus L.) e soja (Glycine max), e nos resíduos de aveia. A chuva simulada (65 mm h-1e 75 minutos) foi aplicada três vezes no milho e quatro vezes no nabo, na soja, e nos resíduos, com um simulador debraços rotativos. Antes e depois da pesquisa, determinou-se o teor de K, Ca e Mg no solo. As chuvas aplicadas em cada momento compuseram um teste (T). O T1 ocorreu após a aplicação do DLS e os demais testes em intervalos que variaram entre 14 e 70 dias, em função do clima. Durante o escoamento, em intervalos de cincominutos coletaram-se amostras de enxurrada para determinar as perdas de água e o teor de K, Ca e Mg na água. O DLS não influenciou o teor dos nutrientes no solo. O teore as perdas totais dos nutrientes foram maiores com 1000 m3ha-1de DLS do que na ausência do dejeto. Com o aumento de escoamento, diminuiu o teor na enxurrada e aumentou a perda total, a qual aumentou também com o aumento de teor dos nutrientes na enxurrada. Recomenda-se aplicar menos do que 500 m3ha-1de DLS total no solo, mesmo em aplicações intervalares, devido à elevada perda de K, Ca e Mg pela erosão hídrica.(AU)

Pigg slurry (PS) is used as a fertilizer whose nutrients are lost through erosion and contaminate the environment if the manure is used inappropriately. The objective was to evaluate the effect of PS on soil and erosion, in a Alfisol soil. The treatments, 0; 50; 100; and 200 m³ ha-1of PS were applied superficially after sowing once in each of the five crops, and in the straw of the last crop, totaling 0, 250, 500 and 1000 m³ ha-1, in oat (Avena strigosa), corn (Zea mays), turnip (Raphanus sativusL.) and soybean (Glycine max), and in oat residues. The simulated rain (65 mm h-1and 75 minutes) was applied three times to corn and four times to turnip, soybeans, and residues, with a rotating arms simulator. Before and after the research, the content of K, Ca and Mg in thesoil was determined. The rainfall applied at each moment made up a test (T). T1 occurred after the application of the PS and the other tests at intervals that varied between 14 and 70 days, depending on the weather. During the runoff, at five-minute intervals, runoff samples were collected to determine water losses and the content of K, Ca and Mg in the water. The PS did not influence the nutrient content in the soil. The content and total losses of nutrients were higher with 1000 m3ha-1of PS than in theabsence of manure. With the increase in runoff, the content inthe runoff decreased and the total loss increased, which also increased with the increase in the nutrient content in the runoff. It is recommended to apply less than 500 m3ha-1of total PS inthe soil, even in interval applications, due to the high loss of K, Ca and Mg by water erosion.(AU)

Hydrogel composed of potassium acrylate, acrylamide, and mineral as soil conditioner under saline conditions

Hydrogels have potential as soil conditioners due to their high capacity to retain water and mitigate soil salinity. However, investigations under saline conditions are necessary because there are losses in both water absorption and salinity mitigation depending on the composition of hydrogel and ions involved in salinity. In this work, we studied a commercial hydrogel in two experiments. The first experiment was conducted in the laboratory to evaluate the absorption by the hydrogel of water with electrical conductivity (EC) of 0.5, 1.5, 3.0, and 4.5 dS m-1, promoted by NaCl. The second experiment was conducted in a greenhouse in a 2 × 4 factorial scheme (with and without hydrogel × EC of the first experiment). Although salinity reduced water absorption by hydrogel by 84 %, the polymer applied in a sandy soil under saline conditions reduced water losses by 58 %. However, hydrogel did not increase the final soil moisture (~ 0.10 g g-1). The polymer reduced Na+ concentration in leachate from 1,499 to 1,219 mg L-1 at the highest salinity level (4.5 dS m-1), but it increased Na+ soil availability by 0.1 mg kg-1 in comparison with polymer absence. Hydrogel application increased Na+ content in plants from 9 to 13 mg kg-1 at the highest salinity, while K+ content was 10 to 16 mg kg-1 lower than that observed without a polymer. Hydrogel 0.07 % (w/w) reduced maize biomass, indicating damage by monovalent ions, compromising the polymer potential under salinity.

Modeling of soil loss by water erosion in the Tietê River Hydrographic Basin, São Paulo, Brazil / Modelagem da perda de solo por erosão hídrica na Bacia Hidrográfica do Rio Tietê, São Paulo, Brasil

Since the mid-16th century, the Tietê River has been an important route for the territorial occupation and exploitation of natural resources in the interior of São Paulo and Brazil. Currently, the Tietê River is well known for environmental problems related to water pollution and contamination. However, little attention has been focused on water erosion, which is a serious issue that affects the soils and waters of the hydrographic basin. Thus, this work aimed to estimate soil loss caused by water erosion in this basin, which has an area of approximately 72,000 km², using the Revised Universal Soil Loss Equation (RUSLE). The RUSLE parameter survey and soil loss calculation were performed using geoprocessing techniques. The RUSLE estimated an average soil loss of 8.9 Mg ha-1 yr-1 and revealed that 18% of the basin's territory presents high erosion rates. These are priority zones for conservation practices to reduce water erosion and ensure long-term soil sustainability. The estimated sediment transport was 1.3 Mg ha-1 yr-1, whereas the observed sedimentation, which was calculated based on data from the fluviometric station, was 0.8 Mg ha-1 yr-1. Thus, the results were equivalent considering the large size of the study area and can be used to assist in managing the basin. Estimating soil losses can help in the planning of sustainable management of the Tietê River Hydrographic Basin and highlights the importance of minimizing water erosion, thus helping to prevent additional pollution and contamination with sediments, agrochemicals, and fertilizers.(AU)

Desde meados do século 16, o rio Tietê tem sido uma importante rota de ocupação territorial e exploração dos recursos naturais do interior de São Paulo e do Brasil. Atualmente, o Rio Tietê é bastante conhecido pelos problemas ambientais relacionados à poluição e contaminação das águas. No entanto, pouca atenção tem sido dada à erosão hídrica, que é um problema sério que afeta os solos e as águas da bacia hidrográfica. Assim, este trabalho teve como objetivo estimar as perdas de solo causadas pela erosão hídrica nesta bacia, que tem uma área de aproximadamente 72.000 km², utilizando a Equação Universal de Perdas de Solo Revisada (RUSLE). O levantamento dos parâmetros RUSLE e o cálculo das perdas de solo foram realizados utilizando técnicas de geoprocessamento. O RUSLE estimou uma perda média de solo de 8,9 Mg ha-1 ano-1 e revelou que 18% do território da bacia apresenta altas taxas de erosão. Estas são zonas prioritárias para práticas de conservação para reduzir a erosão hídrica e garantir a sustentabilidade do solo a longo prazo. O transporte de sedimentos estimado foi de 1,3 Mg ha-1 ano-1, enquanto a sedimentação observada, calculada com base nos dados da estação fluviométrica, foi de 0,8 Mg ha-1 ano-1. Assim, os resultados foram equivalentes considerando a grande extensão da área de estudo e podem ser utilizados para auxiliar na gestão da bacia. A estimativa das perdas de solo pode auxiliar no planejamento do manejo sustentável da Bacia Hidrográfica do Rio Tietê e destacar a importância de minimizar a erosão hídrica, auxiliando na prevenção de poluição adicional e contaminação por sedimentos, agroquímicos e fertilizantes.(AU)

Sensitivity of tuberous roots crops to salinity in a protected environment / Sensibilidade de culturas de raízes tuberosas à salinidade em ambiente protegido

Soil salinity has been a limiting barrier for the production of vegetables in protected environments. Thus, the understanding of the sensitivity of species to this stress factor must be explored, seeking better growing conditions.Under the hypothesis that beet and radish crops are sensitive to variations in soil salinity, even at low levels, the objective of this work was to evaluate the development and productivity of these two species in soils with different salinities in a protected environment. The experimental design was completely randomized and treatments were formed by the soil salinity levels, obtained with the application of saline solution (NaCl in water), considering the soil electrical conductivity of 0.36 dS m-1as low salinity, of 1.05 dS m-1as moderate salinity and 2.43 dS m-1as elevated. For all variables analyzed, except for the relative chlorophyll index in beet plants, it was found that the increase in soil salinity resulted in significant development losses of beet and radish plants. Therefore, we concluded that beet and radish crops are sensitive to the variation in soil salinity, even in relatively low concentrations, making these species an unattractive choice for cultivation in systems that present this problem.(AU)

A salinidade dos solos tem sido uma barreira limitadora para a produção de hortaliças em ambientes protegidos. Assim, o entendimento quanto a sensibilidade das espécies a esse fator de estresse deve ser explorado, buscando melhores condições de cultivo. Sob a hipótese de que as culturas de beterraba e rabanete são sensíveis às variações da salinidade do solo, mesmo em níveis baixos, o objetivo deste trabalho foi avaliar o desenvolvimento e a produtividade dessas duas espécies em solos comdiferentes salinidades em ambiente protegido. O delineamento experimental foi inteiramente casualizado e os tratamentos foram formados pelos níveis de salinidade do solo, obtidos com a aplicação de solução salina (NaCl em água), considerando a condutividade elétrica do solo de 0,36 dS m-1como baixa salinidade, de 1,05 dS m-1como salinidade moderada e 2,43 dS m-1como elevada. Para todas as variáveis analisadas, com exceção do índice relativo de clorofila em plantas de beterraba, verificou-se que o aumento da salinidade do solo resultou em perdas significativas de desenvolvimento de plantas de beterraba e rabanete. Assim, concluímos que as culturas de beterraba e rabanete são sensíveis à variação da salinidade do solo, mesmo em concentrações relativamente baixas, tornando essas espécies uma escolha pouco atrativa para cultivo em sistemas que apresentam este problema.(AU)

Análise quantitativa da receptividade a presença de abrigos de morcegos hematófagos Desmodus rotundus no município de São Pedro - SP / Quantitative analysis of the receptivity of the presence of vampire bats Desmodus rotundus shelters in the municipality of São Pedro - SP / Análisis cuantitativo de la receptividad de la presencia de hematophagus bat shelters Desmodus rotundus en el municipio de São Pedro - SP

O morcego hematófago Desmodus rotundus é o principal transmissor da raiva dos herbívoros, responsável por enormes prejuízos econômicos na pecuária na América Latina. Devido às interações de D. rotundus como meio ambiente, o risco da raiva nos herbívoros pode ser explicado pela vulnerabilidade e a receptividade do ambiente a capacidade do ecossistema albergar populações de D. rotundus. Utilizando de Sistema de Informações Geográficas foram analisados quantitativamente os seguintes determinantes de receptividade em que se encontravam os abrigos de morcegos hematófagos D. rotundus nomunicípio de SãoPedro - SP: tipo de solo e geologia, uso e cobertura do solo, declividade, hipsometria e proximidade a corpos de água. Foram localizados oito abrigos de D. rotundus, sendo dois abrigos naturais: uma gruta de arenito de Geologia Formação Piramboia e Neossolo Quartzarênico habitada por apenas um morcego, e outra gruta basáltica de Geologia Formação Itaqueri e Latossolo Vermelho-amarelo comum a população estimada de 100 D. rotundus. 75% dos abrigos estava em áreas de pastagem e cana de açúcar, seguido por áreas de vegetação nativa e vegetação riparia associada a pastagens. A presença de abrigos de D. rotundus em áreas de cultura canavieira e pastoril em quantidade superior a áreas de cobertura florestal ressalta a importância de oferta de abrigos artificiais em áreas agrícolas. A declividade do terreno em que se encontravam os abrigos variou de 3% a 29%. 62,5% dos abrigos estavam em áreas com baixas declividades com presença de pastagens, porém próximos a áreas de relevo mais escarpado e vegetação nativa com altitudes que variaram entre 475 m e 929 m. Todos os abrigos estavam localizados próximos a corpos d'agua. Apesar de corpos d'agua não constarem como fator de receptividade à presença de abrigos de D. rotundus no modelo epidemiológico indicado pelo Manual de Combate a Raiva dos Herbívoros - MAPA, no presente estudo a proximidade de todos os abrigos de D. rotundus a corpos d'agua evidencia a importância deste fator na receptividade ambiental à presença de abrigos destes morcegos, tornando relevante a inclusão deste fator nos modelos epidemiológicos de controle da raiva dos herbívoros. Desta forma faz-se necessária uma reavaliação da importância dos fatores de receptividade à presença de abrigos de D. rotundus nos modelos epidemiológicos, considerando a escala e particularidades de cada região em estudo, a inclusão outros tipos de formação geológica além da calcária para formação de abrigos naturais, a inclusão de novos tipos e cobertura de solo e a proximidade de corpos d'agua.

The vampire bat Desmodus rotundus is the main transmitter rabies in herbivores, responsible for enormous economic losses in livestock in Latin America. Due to interactions of D. rotundus with the environment, the risk of rabies in herbivores can be explained by the vulnerability and receptiveness of the environment to the capacity of the ecosystem to support populations of D. rotundus. Using a Geographic Information System, the following determinants of receptivity were quantitatively analyzed in which the vampire bat roosts D. rotundus were found in the city of São Pedro - SP: soil type and geology, land use and cover, slope, hypsometry and proximity to water bodies. Eight D. rotundus shelters were located, two of which were natural: as and stone cave of Piramboia Formation Geology and Quartzarênic Neosol inhabited by only one bat, and another basaltic cave of Itaqueri Formation Geology and Red-yellow Latosol with an estimated population of 100 D. rotundus. 75% of the shelters were in pasture and sugar cane areas, followed by areas of native vegetation and riparian vegetation associated with pastures. The presence of D. rotundus shelters in sugar cane and pastoral areas in a greater quantity than in forest cover areas highlights the importance of offering artificial shelters in agricultural areas. The slope of the land on which the shelters were located ranged from 3% to 29%. 62.5% of the shelters were in areas with lows lopes with the presence of pastures, but close to areas with more rugged relief and native vegetation with altitudes ranging between 475m and 929m. All shelters were located close to bodies of water. Although bodies of water do not appear as a factor of receptivity to the presence of shelters of D. rotundus in the epidemiological model indicated by the Herbivore Rabies Control Manual - MAPA, in the present study the proximity of all roosts of D. rotundus to water bodies highlights the importance of this factor in environmental receptivity to the presence of roosts for these bats, making it relevant to include this factor in epidemiological models for controlling rabies in herbivores. Thus, it is necessary to reassess the importance of factors of receptivity to the presence of D. rotundus roosts in epidemiological models, considering the scale and particularities of each region under study, the inclusion of other types of geological formation in addition to limestone for the formation of natural shelters, the inclusion of new types and land cover and the proximity of water bodies.

El murciélago vampiro Desmodus rotundus es el principal transmisor de la rabia herbívora, responsable de enormes pérdidas económicas en la ganadería en América Latina. Debido a las interacciones de D. rotundus con el medio ambiente, el riesgo de rabia en herbívoros puede explicarse por la vulnerabilidad y receptividad del medio ambiente a la capacidad del ecosistema para sustentar poblaciones de D. rotundus. Utilizando un Sistema de Información Geográfica, se analizaron cuantitativamente los siguientes determinantes de la receptividad en los que se encontraron los refugios de murciélagos vampiro D. rotundus en la ciudad de São Pedro SP: tipo de suelo y geología, uso y cobertura del suelo, pendiente, hipsometría y proximidad a cuerpos de agua. Se ubicaron ocho refugios de D.rotundus, siendo dos refugios naturales: una cueva de arenisca de Geología de la Formación Piramboia y Quartzarênico Neosol habitada por un solo murciélago, y otra cueva basáltica de Geología de la Formación Itaqueri y Latosol Rojo-amarillo con una población estimada de 100 D. rotundus. El 75% de los refugios estaban en áreas de pastos y caña de azúcar, seguidos de áreas de vegetación nativa y vegetación de ribera asociada a pastos. La presencia de refugios de D. rotundus en áreas cañeras y pastorales en mayor cantidad que en áreas de cobertura forestal resalta la importancia de ofrecer refugios artificiales en áreas agrícolas. La pendiente del terreno en el que se ubicaron los refugios osciló entre el 3% y el 29%. El 62,5% de los refugios se encontraban en zonas de baja pendiente con presencia de pastos, pero próximas a zonas de relieve más accidentado y vegetación autóctona con altitudes que oscilan entre 475 my 929 m. Todos los refugios estaban ubicados cerca de cuerpos de agua. Si bien los cuerpos de agua no aparecen como factor de receptividad a la presencia de refugios de D. rotundus en el modelo epidemiológico indicado por el Manual de Combate a la Rabia de Herbívoros - MAPA, en el presente estudio la proximidad de todos los refugios de D. rotundus to bodies d'agua destaca la importancia de este factor en la receptividad ambiental a la presencia de refugios para estos murciélagos, por lo que es relevante incluir este factor en los modelos epidemiológicos para el control de la rabia en herbívoros. Así, es necesario reevaluar la importancia de los factores de receptividad a la presencia de refugios de D. rotundus en los modelos epidemiológicos, considerando la escala y particularidades de cada región en estudio, la inclusión de otros tipos de formación geológica además de la caliza para la formación de refugios naturales, inclusión de nuevos tipos y coberturas terrestres y proximidad de cuerpos de agua.

Leptospira spp. of the urinary tract of female carrier goats in semi-arid conditions

Background: Leptospirosis is an important infectious disease in goat farming, with a worldwide distribution. It is usually transmitted by rodents and the genital route, may cause reproductive losses, negatively impacting goat farming. The diagnosis lies on serological, molecular and isolation techniques. Considering the importance of this disease for small ruminants, this work aimed to evaluate the serological, molecular findings and isolation of pathogenic leptospires in the urinary tract (kidney and bladder tissues) of goats. Materials, Methods & Results: Thirty-four adult goats were used for slaughter. Renal samples (n = 34), bladder (n = 34), were collected for isolation of the agent and molecular detection of Leptospira sp. and blood samples (n = 34) for serological testing. The polymerase chain reaction (PCR) was used as a molecular test and the microscopic serum agglutination test (MAT) was used as a serological test. Samples with DNA amplification were subjected to genetic sequencing. The presence of Leptospira DNA was found in the tissues of 8 (23.4%) goats, and of these, only 2 were positive in PCR and MAT. There was a slight agreement between the PCR and MAT techniques (k = 0.150; P = 0.436). In 6 (17.6%) samples of renal tissue and 2 (5.8%) bladder samples, Leptospira DNA was detected. The genes in a kidney tissue sample were sequenced and demonstrated 99% similarity to Leptospira interrogans. Anti-Leptospira sp. were detected in 6 (17.6%) of the animals tested. Discussion: Serology identified 3 predominant serogroups: Icterohaemorrhagiae, Tarassovi and Autumnalis, serogroups that are related to the presence of rodents that coexist in rural environments. Autumnalis has been reported in small ruminants, raising the hypothesis that goats are adapted, becoming chronic carriers and possible maintenance hosts. The frequency obtained (17.6%) may be the result of the mixed breed pattern and rustic characteristics inherent to the goat species. Given the characteristics of the semi-arid region, such as low rainfall and high solar incidence, it is essential to use an adapted methodology, with a lower cut-off point (1:50), as the serological titer is an established relationship between the animal species, the level of exposure throughout its evolution and the region studied. Molecular findings and bacterial isolation reveal the agent's ability to colonize the urinary tract of goats. These data show the importance that urine has in the epidemiological chain, being able to transmit the agent through direct contact with this product or through contamination of soil and water. There was no statistical agreement between the diagnostic techniques used in this study, in this case, an association between PCR and MAT is recommended to obtain data with high sensitivity and specificity. A bladder sample was sequenced and showed 99% similarity to Leptospira interrogans. In the semiarid region, the most common form of leptospirosis spread is through the sale of animals in business fairs for breeding, rearing or slaughter, as well as sharing the same property with several breeders. The introduction of chronic and asymptomatic carriers on the properties represents a serious risk for the spread of the disease. The results show the presence of Leptospira spp. in semi-arid goat herds, having as risk factors the presence of rodents and intercropping. The association of MAT and PCR is necessary for a better diagnosis of the disease.

Supplemental irrigation using brackish water on maize in tropical semi-arid regions of Brazil: yield and economic analysis

ABSTRACT: Supplemental irrigation during dry spells could reduce maize yield losses in tropical semi-arid regions, notably in small farms. However, good quality water reserves are not sufficient to meet the demands of farming communities. Consequently, our objective was to evaluate the productivity and profitability of maize under different simulated rainfall scenarios, with and without supplemental irrigation (SI) with brackish water. The field experiments were carried out during the cropping seasons of 2018 and 2019 on Ultisol. The experiment followed a randomized block design in the split-plot scheme with four replicates. The plots were formed by simulating the water supply in the soil corresponding to four water scenarios (rainy, normal, drought and severe drought), and the sub-plots with or without SI with brackish water (Electrical conductivity of 4.5 dS m1). Mean yields of green maize ears were 13,083, 11,532, 10,358 and 9,609 kg ha1 for rainy, normal, drought and severe drought scenarios, as supplemented with brackish water. For the same treatments without SI the values were 11,394, 7,896, 3,913 and 1,374 kg ha1, respectively. Data on farmer's income showed that under normal, drought and severe drought supplementation with brackish water becomes economically advantageous from 0.9, 1.0 and 2.4 ha, respectively, while maize cultivation without SI is not advantageous under the last two scenarios. For severe drought conditions, however, SI using brackish water reduced commercial yield by 27 % with negative effects on the farmers profitability. In this case, it is necessary to use water with either lower salinity or select salt tolerant crops.

Short-term effect of a crop-livestock-forestry system on soil, water and nutrient loss in the Cerrado-Amazon ecotone / Efeito da integração lavoura-pecuária-floresta em fase inicial sobre as perdas de solo, água e nutrientes no ecótono Cerrado-Amazônia

Soil, water, and nutrient loss by water erosion are among the main factors leading to land degradation, decreasing soil productivity and the provision of ecosystem services. The Cerrado-Amazon ecotone in western Brazil has suffered rapid land-use cover changes with impacts on soil erosion and land degradation. Despite the importance of the region for Brazilian agriculture and environmental conservation, studies on soil, water, and nutrient loss are still scarce. We tested integrated crop-livestockforestry (ICLF) as a sustainable agriculture management system for the Cerrado-Amazon ecotone region. A field experiment was established in the north of Mato Grosso state to quantify total soil, water, carbon and nitrogen loss during the rainy season in 2012-2013 in plots of integrated crop-forestry (ICF), pasture (PAST), eucalyptus plantation (EUC), no-tillage crop succession (CS) and bare soil (BS). Total soil, water, carbon and nitrogen losses in BS were, on average, 96.7% higher than in ICF, EUC, PAST, and CS. ICF had significantly lower water loss than CS, EUC and PAST. Total loss of carbon (4.3 - 428.2 kg ha-1) and nitrogen (0.3 - 29.2 kg ha-1) differed significantly among treatments. The production systems with tree components (EUC and ICF) and PAST showed reduced soil and nutrients loss compared to CS. Our results demonstrated that ICLF can avoid soil quality loss and thus improve agriculture sustainability in the Cerrado-Amazon ecotone.(AU)

A erosão hídrica é um dos principais fatores da degradação dos solos, impactando seu potencial produtivo e capacidade de provisão de serviços ecossistêmicos. O ecótono Cerrado-Amazônia, no norte de Mato Grosso, Brasil, tem sofrido intensas modificações em seu uso e cobertura com impacto na erosão e degradação do solo. Apesar da importância ambiental e agropecuária da região, estudos sobre as perdas de água, solo e nutrientes são escassos. Neste trabalho, testamos a utilidade da integração lavoura-pecuária-floresta (ICLF) para a produção agrícola sustentável no ecótono Cerrado-Amazônia. Foi implantado um experimento de campo no norte de Mato Grosso para quantificar as perdas de solo, água, carbono e nitrogênio durante o período chuvoso de 2012-2013 em parcelas de integração lavoura-floresta (ICF), pastagem (PAST), plantação de eucalipto (EUC), plantio direto com sucessão de culturas (CS) e solo descoberto (BS). As perdas totais de água, solo, carbono e nitrogênio foram, em média, 96,7% maiores em BS, quando comparadas a ICF, EUC, PAST e CS. As perdas de água e solo foram significativamente menores na ICF comparado a CS. As perdas totais de carbono (4.3 - 428.2 kg ha-1) e nitrogênio (1.05 - 10.4 kg ha-1) diferiram significativamente. Os sistemas com um componente arbóreo (EUC e ICF) e PAST tiveram menores perdas de solo e nutrientes em comparação com CS. Nossos resultados demonstraram que ICLF pode evitar a perda de qualidade de solo, melhorando a sustentabilidade da agricultura no ecótono Cerrado-Amazônia.(AU)

Soil losses in the State of Rondônia, Brazil / Perdas de solo no Estado de Rondônia, Brasil

In the state of Rondônia, deforestation, and inadequate soil use and management have intensified the water erosion process, causing degradation of agricultural land. Modeling is a tool that can assist in the adoption of targeted and effective measures for soil and water conservation in the region. In this context, the objective of the research was to model soil losses due to water erosion in the state of Rondônia using the Revised Universal Soil Loss Equation (RUSLE). The parameters related to rain erosivity, relief, erodibility, and soil cover, as well as the conservation practices of the state of Rondônia, were considered. The modeling steps were performed with the aid of the Geographic Information System. Results were validated with data of total sediments transported with water discharge. The estimated total soil loss was about 605 million tons per year, corresponding to an average loss of 22.50 Mg ha-1 year-1. In 19% of the state, the erosion rate was higher than the soil loss tolerance(T), and these areas should be prioritized for adopting measures to mitigate the erosion process. The RUSLE underestimated the generation of sediments at 0.56 Mg ha-1 year-1, which corresponds to an error of 18.60%. Results obtained can assist in the development of different soil use and management scenarios and provide options for policymakers to encourage soil conservation in the state of Rondônia.(AU)

No Estado de Rondônia, o desmatamento, o uso e o manejo inadequado dos solos têm intensificado o processo de erosão hídrica, gerando a degradação de terras agrícolas. Nesse cenário, a modelagem é uma ferramenta que pode auxiliar na adoção de medidas direcionadas e eficazes de conservação do solo e da água na região. Assim, o objetivo do trabalho foi modelar as perdas de solo por erosão hídrica no Estado de Rondônia utilizando a Equação Universal de Perda de Solo Revisada (RUSLE). Foram considerados os parâmetros referentes a erosividade da chuva, relevo, erodibilidade e cobertura do solo e as práticas conservacionistas do Estado de Rondônia. As etapas da modelagem foram realizadas com auxílio de Sistema de Informações Geográficas. Os resultados foram validados com dados de coleta de sedimentos totais transportados com a descarga dágua. A perda de solo total estimada foi cerca de 605 milhões de toneladas ao ano, correspondente a uma perda média de 22,50 Mg ha-1 ano-1. Em 19% do Estado a taxa erosiva foi superior aos limites de tolerância de perda de solo (TPS), sendo que essas áreas devem ser priorizadas para adoção de medidas de mitigação do processo erosivo. A RUSLE subestimou a geração de sedimentos em 0,56 Mg ha-1 ano-1, o que corresponde a um erro de 18,60%. Os resultados obtidos podem contribuir para elaborar distintos cenários de manejo e uso do solo e fornecer alternativas aos formuladores de políticas agrícolas e ambientais, com o intuito de incentivo a conservação do solo no Estado de Rondônia.(AU)

Increased vegetation ground cover reduces water, sediment and phosphorus losses in Cambisol treated with swine slurry / O aumento da cobertura vegetal do solo reduz as perdas de água, sedimentos e fósforo em Cambissolo tratado com dejetos suínos

This study aims to evaluate the influence of the ground cover rate bycrop residues and the rain time elapsed after the application of liquid swine slurry (LSS) under losses of water, sediments, and phosphorus (P). The study was carried out under a Humic Cambisols. Two areas were delimited: with and without the applicationof LSS. Each area was subdivided intofour levels of crop residues: 5%, 35%, 65%, and 95%. Vegetable residues present in the area, from corn and black oat, were used. Three collecting gutters of 0.60 m² were installed in each subplot. Simulated rain was carried out on these, and the runoff volume collected for quantification and determination of losses. With LSS application, increase in the cover rate by crop residues reduces 0.3 mm h-1the runoff volume and 1.67 mg m-2reactive soluble P (H2O-P). The sediment lossesin the first collection after the beginning of the rain were 23 times lower in the soil with 95% ground cover than in the soil with 5% ground cover. The loss of total P (total-P) decreases with the increase of the ground cover of the soil and increases inthe same way with the increase of the time.

Este trabalho objetivouavaliar a influência da taxa de cobertura do solo por resíduos culturais e o tempo de chuvadecorrido após a aplicação de dejetoslíquidos de suínos (LSS) sob perdas de água, sedimentos e fósforo (P). O estudo foi realizado sob um Cambissolo Húmico. Duas áreas foram delimitadas: com e sem aplicação de LSS. Cada área foi subdividida em quatro níveis de resíduos culturais: 5%, 35%, 65% e 95%. Foram utilizados resíduos vegetais presentes na área, provenientes de milho e aveia preta. Em cada subparcela foram instaladas três calhas coletoras de 0,60 m². Sobre estes foi realizada chuva simulada, sendo ovolume deenxurrada coletado para quantificação e determinação das perdas. Com a aplicação de LSS, o aumento da taxa de cobertura por resíduos culturais reduziuem 0,3 mm h-1o volume do escoamento e em 1,67 mg m-2de P solúvel reativo (H2O-P). As perdasde sedimento na primeira coleta após o início da chuva foram 23 vezes menores no solo com 95% de cobertura do que no solo com 5% de cobertura. A perda de P total (P total) diminui com o aumento da cobertura do solo e aumenta da mesma forma com o aumento do tempo.

Increased vegetation ground cover reduces water, sediment and phosphorus losses in Cambisol treated with swine slurry / O aumento da cobertura vegetal do solo reduz as perdas de água, sedimentos e fósforo em Cambissolo tratado com dejetos suínos

This study aims to evaluate the influence of the ground cover rate bycrop residues and the rain time elapsed after the application of liquid swine slurry (LSS) under losses of water, sediments, and phosphorus (P). The study was carried out under a Humic Cambisols. Two areas were delimited: with and without the applicationof LSS. Each area was subdivided intofour levels of crop residues: 5%, 35%, 65%, and 95%. Vegetable residues present in the area, from corn and black oat, were used. Three collecting gutters of 0.60 m² were installed in each subplot. Simulated rain was carried out on these, and the runoff volume collected for quantification and determination of losses. With LSS application, increase in the cover rate by crop residues reduces 0.3 mm h-1the runoff volume and 1.67 mg m-2reactive soluble P (H2O-P). The sediment lossesin the first collection after the beginning of the rain were 23 times lower in the soil with 95% ground cover than in the soil with 5% ground cover. The loss of total P (total-P) decreases with the increase of the ground cover of the soil and increases inthe same way with the increase of the time.(AU)

Este trabalho objetivouavaliar a influência da taxa de cobertura do solo por resíduos culturais e o tempo de chuvadecorrido após a aplicação de dejetoslíquidos de suínos (LSS) sob perdas de água, sedimentos e fósforo (P). O estudo foi realizado sob um Cambissolo Húmico. Duas áreas foram delimitadas: com e sem aplicação de LSS. Cada área foi subdividida em quatro níveis de resíduos culturais: 5%, 35%, 65% e 95%. Foram utilizados resíduos vegetais presentes na área, provenientes de milho e aveia preta. Em cada subparcela foram instaladas três calhas coletoras de 0,60 m². Sobre estes foi realizada chuva simulada, sendo ovolume deenxurrada coletado para quantificação e determinação das perdas. Com a aplicação de LSS, o aumento da taxa de cobertura por resíduos culturais reduziuem 0,3 mm h-1o volume do escoamento e em 1,67 mg m-2de P solúvel reativo (H2O-P). As perdasde sedimento na primeira coleta após o início da chuva foram 23 vezes menores no solo com 95% de cobertura do que no solo com 5% de cobertura. A perda de P total (P total) diminui com o aumento da cobertura do solo e aumenta da mesma forma com o aumento do tempo.(AU)

Sistema Santa Fé auxilia na redução do escoamento superficial e melhoria da qualidade da água? / Santa Fé System assists in reducing runoff and improvement the quality of water?

A cobertura vegetal na superfície do solo é uma prática fundamental para o estabelecimento de sistemas conservacionistas do solo e da água. O Sistema Santa Fé consiste na inclusão de espécies forrageiras no sistema de produção de grãos, sobretudo por consorciação. O objetivo do estudo foi avaliar o efeito do cultivo do milho solteiro e do milho em consórcio com capim U. brizantha cv. marandu, no escoamento superficial e qualidade da água escoada utilizando um simulador de chuvas.O experimento foi realizado na Fazenda Escola do IF Goiano Campus Iporá em Neossolo Quartzarênico argiloso, em uma região do Cerrado. As seguintes coberturas do solo foram avaliadas: solo descoberto, milho híbrido solteiro e Sistema Santa Fé. Para a determinação do volume escoado e a qualidade da água escoada em cada tratamento foram realizados três testes, utilizando-se um simulador de chuvas pendular construído no IF Goiano Campus Iporá. Em cada teste foram contabilizadas o volume total de água escoada e a cada cinco minutos foram coletadas amostras para caracterização da qualidade da água, nas quais foram analisadas a turbidez, pH e condutividade elétrica. As perdas de água foram reduzidas 82% e a turbidez em 96% no sistema Santa Fé, em comparação ao solo descoberto. O Sistema Santa Fé apresentou melhor desempenho com menor volume de escoamento superficial e melhor qualidade da água escoada quando avaliada a turbidez, o que demonstra o seu elevado potencial em minimizar a erosão hídrica do solo.(AU)

The cover crop on the soil surface is a fundamental practice for the establishment of soil and water conservation systems.The Santa Fé System consists of the inclusion of forage species in the grain production system, mainly by intercropping. The objective of the study was to evaluate the effect of cultivation of single maize and maize in consortium with U. brizantha cv. marandu, in runoff and quality of run off using a rainfall simulator. The experiment was carried out at the School Farm of the IF Goiano Campus Iporá in a Quartzipsament, in a Brazilian Savanna region. The following land cover were evaluated: uncovered soil, single hybrid corn and Santa Fé System. For the determination of the runoff volume and the runoff quality, three tests were performed in each treatment, using a pendulum rainfall simulator built at the IF Goiano Campus Iporá. In each test, the total volume of runoff was counted and every five minutes samples were collected to characterize the runoff quality, in which turbidity, pH and electrical conductivity were analyzed. Water losses were reduced by 82% and turbidity by 96% in the Santa Fé system, compared to uncovered soil.The Santa Fé System showed better performance with less runoff volume and better quality of runoff when turbidity was evaluated, which demonstrates its high potential in minimizing soil water erosion.(AU)

Sistema Santa Fé auxilia na redução do escoamento superficial e melhoria da qualidade da água? / Santa Fé System assists in reducing runoff and improvement the quality of water?

A cobertura vegetal na superfície do solo é uma prática fundamental para o estabelecimento de sistemas conservacionistas do solo e da água. O Sistema Santa Fé consiste na inclusão de espécies forrageiras no sistema de produção de grãos, sobretudo por consorciação. O objetivo do estudo foi avaliar o efeito do cultivo do milho solteiro e do milho em consórcio com capim U. brizantha cv. marandu, no escoamento superficial e qualidade da água escoada utilizando um simulador de chuvas.O experimento foi realizado na Fazenda Escola do IF Goiano Campus Iporá em Neossolo Quartzarênico argiloso, em uma região do Cerrado. As seguintes coberturas do solo foram avaliadas: solo descoberto, milho híbrido solteiro e Sistema Santa Fé. Para a determinação do volume escoado e a qualidade da água escoada em cada tratamento foram realizados três testes, utilizando-se um simulador de chuvas pendular construído no IF Goiano Campus Iporá. Em cada teste foram contabilizadas o volume total de água escoada e a cada cinco minutos foram coletadas amostras para caracterização da qualidade da água, nas quais foram analisadas a turbidez, pH e condutividade elétrica. As perdas de água foram reduzidas 82% e a turbidez em 96% no sistema Santa Fé, em comparação ao solo descoberto. O Sistema Santa Fé apresentou melhor desempenho com menor volume de escoamento superficial e melhor qualidade da água escoada quando avaliada a turbidez, o que demonstra o seu elevado potencial em minimizar a erosão hídrica do solo.

The cover crop on the soil surface is a fundamental practice for the establishment of soil and water conservation systems.The Santa Fé System consists of the inclusion of forage species in the grain production system, mainly by intercropping. The objective of the study was to evaluate the effect of cultivation of single maize and maize in consortium with U. brizantha cv. marandu, in runoff and quality of run off using a rainfall simulator. The experiment was carried out at the School Farm of the IF Goiano Campus Iporá in a Quartzipsament, in a Brazilian Savanna region. The following land cover were evaluated: uncovered soil, single hybrid corn and Santa Fé System. For the determination of the runoff volume and the runoff quality, three tests were performed in each treatment, using a pendulum rainfall simulator built at the IF Goiano Campus Iporá. In each test, the total volume of runoff was counted and every five minutes samples were collected to characterize the runoff quality, in which turbidity, pH and electrical conductivity were analyzed. Water losses were reduced by 82% and turbidity by 96% in the Santa Fé system, compared to uncovered soil.The Santa Fé System showed better performance with less runoff volume and better quality of runoff when turbidity was evaluated, which demonstrates its high potential in minimizing soil water erosion.

Supplemental irrigation using brackish water on maize in tropical semi-arid regions of Brazil: yield and economic analysis

Supplemental irrigation during dry spells could reduce maize yield losses in tropical semi-arid regions, notably in small farms. However, good quality water reserves are not sufficient to meet the demands of farming communities. Consequently, our objective was to evaluate the productivity and profitability of maize under different simulated rainfall scenarios, with and without supplemental irrigation (SI) with brackish water. The field experiments were carried out during the cropping seasons of 2018 and 2019 on Ultisol. The experiment followed a randomized block design in the split-plot scheme with four replicates. The plots were formed by simulating the water supply in the soil corresponding to four water scenarios (rainy, normal, drought and severe drought), and the sub-plots with or without SI with brackish water (Electrical conductivity of 4.5 dS m−1). Mean yields of green maize ears were 13,083, 11,532, 10,358 and 9,609 kg ha−1 for rainy, normal, drought and severe drought scenarios, as supplemented with brackish water. For the same treatments without SI the values were 11,394, 7,896, 3,913 and 1,374 kg ha−1, respectively. Data on farmer's income showed that under normal, drought and severe drought supplementation with brackish water becomes economically advantageous from 0.9, 1.0 and 2.4 ha, respectively, while maize cultivation without SI is not advantageous under the last two scenarios. For severe drought conditions, however, SI using brackish water reduced commercial yield by 27 % with negative effects on the farmers’ profitability. In this case, it is necessary to use water with either lower salinity or select salt tolerant crops.

Supplemental irrigation using brackish water on maize in tropical semi-arid regions of Brazil: yield and economic analysis

Supplemental irrigation during dry spells could reduce maize yield losses in tropical semi-arid regions, notably in small farms. However, good quality water reserves are not sufficient to meet the demands of farming communities. Consequently, our objective was to evaluate the productivity and profitability of maize under different simulated rainfall scenarios, with and without supplemental irrigation (SI) with brackish water. The field experiments were carried out during the cropping seasons of 2018 and 2019 on Ultisol. The experiment followed a randomized block design in the split-plot scheme with four replicates. The plots were formed by simulating the water supply in the soil corresponding to four water scenarios (rainy, normal, drought and severe drought), and the sub-plots with or without SI with brackish water (Electrical conductivity of 4.5 dS m−1). Mean yields of green maize ears were 13,083, 11,532, 10,358 and 9,609 kg ha−1 for rainy, normal, drought and severe drought scenarios, as supplemented with brackish water. For the same treatments without SI the values were 11,394, 7,896, 3,913 and 1,374 kg ha−1, respectively. Data on farmer's income showed that under normal, drought and severe drought supplementation with brackish water becomes economically advantageous from 0.9, 1.0 and 2.4 ha, respectively, while maize cultivation without SI is not advantageous under the last two scenarios. For severe drought conditions, however, SI using brackish water reduced commercial yield by 27 % with negative effects on the farmers profitability. In this case, it is necessary to use water with either lower salinity or select salt tolerant crops.(AU)

Antifungal activity of homeopathic medicines against the white mold causing agent Sclerotinia sclerotiorum

White mold disease, caused by fungus Sclerotinia sclerotiorum (Lib.) de Bary., is a disease hard to control due to the high amount of sclerotia produced, which guarantees its survival in the soil for years leading to significant yield losses. Alternative techniques to control the pathogen have been researched, including homeopathy. The present work aimed to evaluate the in vitro antifungal effect of homeopathic medicines on S. sclerotiorum mycelial growth. Homeopathic medicines Sulphur, fungal sclerotium Nosode and Calcarea carbonica, in 30CH, 200CH and 1000CH dynamizations were tested. Assays were carried out in a completely randomized design, with four repetitions. Experiments were performed through the addition of homeopathic medicines on the surface of plates containing culture medium, followed by insertion of a disc containing fungus mycelia and incubation. Control treatment received no homeopathic medicine. The mycelial progression was monitored by seven halo diameter measurements during experiment period. All homeopathic medicines tested and their dynamizations were able to inhibit partially the development of the fungus. Calcarea carbonica at the dynamization of 1000 CH showed the best inhibitory effect on S. sclerotiorum, which under its effect produced a mycelial halo 40% smaller than the control treatment.

Antifungal activity of homeopathic medicines against the white mold causing agent Sclerotinia sclerotiorum

White mold disease, caused by fungus Sclerotinia sclerotiorum (Lib.) de Bary., is a disease hard to control due to the high amount of sclerotia produced, which guarantees its survival in the soil for years leading to significant yield losses. Alternative techniques to control the pathogen have been researched, including homeopathy. The present work aimed to evaluate the in vitro antifungal effect of homeopathic medicines on S. sclerotiorum mycelial growth. Homeopathic medicines Sulphur, fungal sclerotium Nosode and Calcarea carbonica, in 30CH, 200CH and 1000CH dynamizations were tested. Assays were carried out in a completely randomized design, with four repetitions. Experiments were performed through the addition of homeopathic medicines on the surface of plates containing culture medium, followed by insertion of a disc containing fungus mycelia and incubation. Control treatment received no homeopathic medicine. The mycelial progression was monitored by seven halo diameter measurements during experiment period. All homeopathic medicines tested and their dynamizations were able to inhibit partially the development of the fungus. Calcarea carbonica at the dynamization of 1000 CH showed the best inhibitory effect on S. sclerotiorum, which under its effect produced a mycelial halo 40% smaller than the control treatment.(AU)

Genetic Similarities of Escherichia Coli Isolated from Different Substrates of the Broiler Production Chain

Brazil is the largest exporter of chicken meat and poultry farming is one of the most important productive segments, despite major losses due to the bacterium Escherichia coli, which is also a zoonotic microorganism. The objetive of this study was to isolate E. coli and to evaluate its transmissibility potential from the field to chicken meat using the Pulsed Field Gel Electrophoresis (PFGE) technique. Environmental samples (poultry litter, soil and water) were collected from broiler farms located in the South of Brazil where the majority of the Brazilian poultry production occurs. In addition, chicken meat (gizzard, heart, drumette and tulip) samples were collected from local supermarkets. As results, 47.36% of the samples were positives for E. coli. Furthermore, 10 pairs of clones of E. coli were found always in the same substrate (two water-water pairs; three soil-soil pairs and five meat-meat pairs) using PFGE. These findings suggest that certain strains of E. coli may have habitat preferences, making the transfer from one substrate type to another more difficult to occur. Moreover, since no clones were found between environmental samples and chicken meat, it is possible to imply a low risk of E. coli transmissibility throughout the chicken meat production chain.(AU)

Genetic Similarities of Escherichia Coli Isolated from Different Substrates of the Broiler Production Chain

Brazil is the largest exporter of chicken meat and poultry farming is one of the most important productive segments, despite major losses due to the bacterium Escherichia coli, which is also a zoonotic microorganism. The objetive of this study was to isolate E. coli and to evaluate its transmissibility potential from the field to chicken meat using the Pulsed Field Gel Electrophoresis (PFGE) technique. Environmental samples (poultry litter, soil and water) were collected from broiler farms located in the South of Brazil where the majority of the Brazilian poultry production occurs. In addition, chicken meat (gizzard, heart, drumette and tulip) samples were collected from local supermarkets. As results, 47.36% of the samples were positives for E. coli. Furthermore, 10 pairs of clones of E. coli were found always in the same substrate (two water-water pairs; three soil-soil pairs and five meat-meat pairs) using PFGE. These findings suggest that certain strains of E. coli may have habitat preferences, making the transfer from one substrate type to another more difficult to occur. Moreover, since no clones were found between environmental samples and chicken meat, it is possible to imply a low risk of E. coli transmissibility throughout the chicken meat production chain.