Resumo em Português:

RESUMO Investigações sobre as etapas de armazenamento e secagem na pós-colheita de frutos de macaúba (Acrocomia aculeata (Jacq.) Lodd. Mart) ainda são incipientes. Desta forma, objetivou-se estudar o efeito da secagem na qualidade do óleo de amêndoas de macaúba durante o armazenamento. A secagem foi realizada em três condições de ar: 40; 50 e 60 ºC. Foram utilizadas quatro repetições para cada temperatura. Após a secagem, as amêndoas foram armazenadas durante 0; 60; 120; 240 e 360 dias, e em cada período, foram realizadas as seguintes análises físico-químicas: teor de óleo da amêndoa; índice de acidez; estabilidade oxidativa; atividade de água e cor do óleo. O aumento no período de armazenamento ocasionou elevação no índice de acidez e redução na estabilidade oxidativa do óleo para todos os tratamentos. Os valores médios de atividade de água no óleo variaram de 0.56 - 0.68. Os valores médios das coordenadas L* e b*, não diferiram do controle, com exceção dos períodos de armazenamento de 0 e 60 dias. Com relação à coordenada a*, houve diferença entre os processos de secagem, quando comparados ao controle. Não foram observadas diferenças significativas para o teor de óleo. Conclui-se que a secagem pode ser tornar ferramenta eficiente no controle da qualidade do óleo de amêndoa ao longo do armazenamento.

Resumo em Inglês:

ABSTRACT Studies of post-harvest storage and drying in macauba fruit (Acrocomia aculeata (Jacq.) Lodd. Mart) are still in the early stages. The aim of this work was to investigate the effect of drying on the quality of macauba kernel oil during storage. Drying was carried out under three different air temperatures: 40°C, 50°C and 60°C. Four replications were used for each temperature. After drying, the kernels were stored for 0, 60, 120, 240 and 360 days, and the following physico-chemical analyses were carried out for each period: kernel oil content, acidity index, oxidative stability, water activity and oil colour. An increase in storage time resulted in an increase in the acidity index and a reduction in the oxidative stability of the oil in all treatments. The mean value for water activity in the oil ranged from 0.56 to 0.68. The mean values of the L* and b* coordinates did not differ from the control, except for the storage times of 0 and 60 days. There was a difference in the a* coordinate between the drying processes when compared to the control. No significant differences were seen for oil content. It was concluded that drying can be efficient tool in controlling the quality of kernel oil during storage.

Resumo em Português:

RESUMO O uso de índices de vegetação apresenta bom potencial para a predição da produtividade de diversas culturas, porém fatores como a época de avaliação, cultivares e fenologia da planta podem influenciar na performance de modelos preditivos. O objetivo do trabalho foi avaliar e comparar a precisão de estimativa da produtividade do feijoeiro, em função do índice de vegetação NDVI, utilizando modelos individuais por cultivar e geral com todas as cultivares. Foram avaliadas as cultivares IAC Imperador e IPR Campos Gerais, de hábitos de crescimento determinado e indeterminado, respectivamente. Foram submetidas a diferentes manejos de fornecimento de nitrogênio, a fim de proporcionar variação da produtividade. Foram realizadas avaliações do NDVI ao longo do ciclo da cultura, em 6 datas, durante estádios vegetativos e reprodutivos. A produtividade de grãos do feijão pode ser estimada com elevada performance em função do índice de vegetação NDVI, obtendo-se R2 de até 78% e erro médio próximo de 350 kg ha-1. Os melhores ajuste de estimativa são obtidas em estádios fenológicos reprodutivos do feijão, especialmente após o florescimento da cultura (R6). Modelos generalistas, compostos por dados de mais de uma cultivar, apresentam precisão semelhante e, em alguns casos, superior aos modelos ajustados para cada cultivar, demonstrando a viabilidade da utilização de um mesmo modelo para vários genótipos.

Resumo em Inglês:

ABSTRACT The use of vegetation indices has good potential for predicting the productivity of several crops, but factors such as the time of assessment, cultivar, and plant phenology can influence the performance of predictive models. The objective of this study was to evaluate and compare the precision of estimating the common bean grain yield, according to the normalized difference vegetation index (NDVI), using individual models per cultivar and a general model with all cultivars. The cultivars IAC Imperador and IPR Campos Gerais, with determined and indeterminate growth habits, respectively, were evaluated. They were subjected to different nitrogen management methods to provide grain yield variability. NDVI evaluations were conducted throughout the culture cycle on six dates during the vegetative and reproductive stages. The common bean grain yield was estimated with high precision as a function of NDVI, obtaining a precision of up to 78% and an average error close to 350 kg ha-1. The greatest fit of estimation was obtained in the phenological reproductive stages of beans, especially after crop flowering. General models, composed of data from more than one cultivar, had similar precision and, in some cases, superiority to the fitted models for each cultivar, demonstrating the feasibility of using the same model for several genotypes.

Resumo em Português:

RESUMO Estresses abióticos associados causam efeitos e respostas diferentes da exposição a uma única fonte de estresse. Objetivou-se avaliar o efeito do estresse combinado de temperatura supraótima e déficit hídrico no processo germinativo de lotes de sementes de trigo com diferentes níveis de vigor. Sementes de trigo IPR Catuara de quatro lotes foram submetidas a germinação nos potenciais hídricos 0,000, - 0,075, - 0,223 e - 0,444 MPa, associados às temperaturas 20, 24, 28 e 32 ºC, totalizando 16 combinações de estresse. O delineamento experimental foi inteiramente casualizado, com quatro repetições, em esquema fatorial: quatro lotes x 16 combinações de estresse, e comparação de médias por Scott-Knott 5%. Avaliaram-se a germinação das plântulas normais aos quatro e oito dias, o conteúdo de proteína total e a atividade da catalase e ascorbato peroxidase (APX) na parte aérea e radicular das plântulas. As análises de componentes principais e de agrupamento hierárquico foram aplicadas à matriz original formada pelas 16 combinações, para a média dos quatro lotes. Sementes de trigo de maior vigor são mais tolerantes a combinação dos estresses hídrico e térmico. Não há prejuízo ao processo germinativo de trigo nas combinações sob temperaturas supraótimas até 28 °C e redução dos potenciais hídricos até -0,223 MPa. Independente da temperatura, o potencial hídrico -0,444 MPa diminui a porcentagem e a velocidade da germinação. A atividade da APX aumenta em condições de estresses hídrico e térmico atuando como defesa ao estresse oxidativo na germinação de trigo.

Resumo em Inglês:

ABSTRACT Combined abiotic stresses have different effects and responses than exposure to a single source of stress. The objective of this study was to evaluate the effect of the combined stress of supra-optimal temperatures and water deficit on the germination of wheat seeds with different levels of vigor. Wheat seeds from four different lots of the IPR Catuara cultivar were germinated at water potentials of 0.000, -0.075, -0.223, and -0.444 MPa, associated with temperatures of 20 °C, 24 °C, 28 °C, and 32 °C, totaling 16 stress combinations. The experimental design was completely randomized in a factorial scheme with four replications (four seed lots × 16 stress combinations), and means were compared using Scott-Knott 5%. We evaluated the germination of normal seedlings at 4 and 8 d, the activity of catalase and ascorbate peroxidase (APX), and the protein content of the aerial and root parts of wheat seedlings. Principal components analysis and hierarchical clustering were applied to the original matrix formed by the 16 combinations for the average of the four lots. Wheat seeds with higher vigor were more tolerant to combined water and thermal stress. Temperatures up to 28 °C and reduction of water potentials down to -0.223 MPa did not prejudice the germination process of wheat seeds. Regardless of temperature, a water potential of -0.444 MPa decreased the percentage and rate of germination. APX activity increased under water stress and supra-optimal temperatures, acting as a defense mechanism against oxidative stress.

Resumo em Português:

RESUMO No Brasil para conservar o solo e a água faz-se necessário a adoção do pacote tecnológico da agricultura conservacionista, em conjunto com o plantio em nível e o uso dos terraços agrícolas. Porém pouco se sabe sobre a percepção e o nível de adoção dessas práticas pelos agricultores. Neste contexto, o objetivo do estudo foi verificar a percepção e o nível de adoção de práticas de conservação do solo e da água por agricultores, em áreas agrícolas com culturas anuais, o objetivo do estudo foi verificar a percepção e o nível de adoção de práticas de conservação do solo e da água por agricultores, em áreas agrícolas com culturas anuais, em uma bacia hidrográfica; além de analisar a relação entre a adoção destas práticas e as características socioeconômicas destes agricultores. Para tanto, foi realizada uma pesquisa do tipo survey junto a agricultores da bacia hidrográfica do Rio Vermelho, no sul do Brasil. Com base nos resultados, verificou-se que a grande maioria dos agricultores tem percepção adequada acerca do uso das práticas de conservação do solo e da água. A manutenção da produtividade foi apontada como principal motivo para se conservar o solo e a água, enquanto que a redução de custo de produção e o controle da erosão aparecem como motivos secundários. O uso dos terraços agrícolas e o plantio direto foram as práticas mais adotadas pelos agricultores, e a rotação de culturas foi a menos adotada. Cerca de 78,3% dos proprietários de terra e 50% dos arrendatários adotaram o plantio direto. Porém, apenas 26,8% dos agricultores adotaram a agricultura conservacionista. No geral, verificou-se que a maioria dos agricultores adota medidas conservacionistas, mas de forma parcial, que podem não ser suficientes para garantir a conservação do solo e a da água. A conscientização sobre a conservação do solo e da água precisa ser melhorada.

Resumo em Inglês:

ABSTRACT In Brazil, to conserve soil and water, the adoption of a complete array of conservation agriculture technologies in conjunction with contour farming and agricultural terraces is necessary. However, there is little knowledge about the awareness and adoption level of conservationist practices by farmers. In this context, the objective of the study, which took place in a watershed containing agricultural areas dominated by annual crops, was to verify farmers’ perception and adoption level of soil and water conservation practices and the relationship between their adoption level of conservation practices and their socioeconomic characteristics. For this purpose, a survey was carried out with farmers in the Rio Vermelho watershed in southern Brazil. It was found that the majority of farmers have adequate awareness about the use of soil and water conservation practices. Maintaining productivity was identified as the main reason to conserve soil and water, while reducing production costs and controlling erosion stood out as secondary reasons. Agricultural terraces and no-tillage were the most adopted practices by farmers. No-tillage was implemented by approximately 78.3% of landowners and 50% of tenants. However, only 26.8% of farmers adopted conservation agriculture. Overall, most farmers adopt conservationist practices, but in a partial manner, which may not be sufficient to ensure soil and water conservation. Awareness of soil and water conservation needs to be further improved.

Resumo em Português:

RESUMO O feijão-caupi verde é uma importante alternativa para a geração de emprego e renda para os agricultores familiares, contribuindo para expansão de sua produção e consumo. No entanto, fatores bióticos como insetos, fungos, bactérias, nematoides e vírus têm limitado sua produção, destacando-se os vírus Cowpea Severe Mosaic Virus (CPSMV) e Cowpea aphid-borne mosaic virus (CABMV). O controle mais eficiente desses vírus é por meio da utilização de variedades resistentes, porém poucas são as variedades destinadas para a produção de feijão verde que são resistentes. Dessa forma, objetivou-se desenvolver e identificar linhagens superiores de feijão-caupi quanto à resistência simultânea aos vírus CPSMV e CABMV com características associadas à produção de grãos verdes. Foram realizados cruzamentos em casa de vegetação no Instituto Agronômico de Pernambuco-AIP entre os genótipos Sempre Verde Salgueiro (suscetível), CNC-0434 (imune ao CPSMV) e TVu-966 (resistente ao CABMV). A partir dos cruzamentos foram selecionadas 50 linhagens F2:5 com coloração do grão tipo Sempre Verde, sendo avaliada a resistência aos vírus em casa de vegetação e as suas características agronômicas para produção de grãos verdes em experimento na Estação Experimental do AIP em Belém do São Francisco-PE. O delineamento experimental foi em blocos casualizados completos, com três repetições. As linhagens L300.026, L300.039, L300.040 e L300.049 mostraram-se resistentes a ambos os vírus e possuem elevado potencial para a produção de grãos verdes; o índice de seleção de Mulamba e Mock facilitou a seleção de linhagens superiores e promissoras para futuro lançamentos de novas variedades resistentes destinadas à produção de grãos verdes.

Resumo em Inglês:

ABSTRACT Green cowpea is an important alternative for generating employment and income for family farmers and helps broaden production and consumption of the grain. However, biotic factors such as insects, fungi, bacteria, nematodes and viruses have hampered production, especially the Cowpea Severe Mosaic Virus (CPSMV) and Cowpea Aphid-Borne Mosaic Virus (CABMV). The most efficient control of these viruses is via the use of resistant varieties, but few varieties intended for green-grain production are resistant. As such, the aim of this study was to develop and identify superior strains of cowpea in terms of joint resistance to the CPSM and CABM viruses that show characteristics associated with green-grain production. Crosses were carried out in a greenhouse at the Agronomic Institute of Pernambuco (AIP) between the following genotypes: Sempre Verde Salgueiro (susceptible), CNC-0434 (immune to CPSMV) and TVu-966 (resistant to CABMV). From these crosses, fifty F2:5 strains with the Sempre Verde type of grain colouring were selected, their resistance to the viruses assessed in a greenhouse, and their agronomic characteristics for green-grain production evaluated in an experiment at the Experimental Station of the AIP in Belém do São Francisco, Pernambuco. The experimental design was of completely randomised blocks, with three replications. The L300.026, L300.039, L300.040 and L300.049 strains proved to be resistant to both viruses, with a high potential for green-grain production. The Mulamba-Mock selection index facilitated the selection of superior strains that are promising for the future launch of new resistant varieties destined for the production of green grains.

Resumo em Português:

RESUMO O desenvolvimento de novas linhagens de feijão com caracteres que atendam a preferência dos consumidores aumenta a sua probabilidade de uso na alimentação. Os objetivos desse trabalho foram avaliar a variabilidade genética de linhagens e cultivares de feijão para caracteres da qualidade de grãos e concentração de minerais e selecionar as linhagens superiores usando o índice de soma de ranks com pesos econômicos diferenciados. Os experimentos foram conduzidos em duas épocas de cultivo para avaliar 17 genótipos de feijão. Os dez caracteres da qualidade de grãos e a concentração de sete minerais foram determinados em grãos crus. Efeito significativo para genótipo foi observado para 15 caracteres e interação genótipo x ambiente significativa foi constatada para 14 caracteres. Alta herdabilidade (≥ 60,00%) e estimativas de ganho genético favoráveis aos objetivos da seleção de linhagens de feijão de grãos claros e escuros superiores para a maioria dos caracteres da qualidade de grãos e concentração de minerais foram obtidas. As linhagens e cultivares de feijão apresentam variabilidade genética para todos os caracteres da qualidade de grãos e concentração de minerais, exceto para a concentração de cobre. Quatro genótipos de feijão carioca (LEC 04-16, Linhagem 110, UEM 266 e Pérola) e quatro genótipos de feijão preto (TB 17-03, SM 1510, BRS Intrépido e Fepagro Triunfo) são superiores para vários caracteres da qualidade de grãos e possuem alta concentração de potássio, fósforo, cálcio e ferro, evidenciando potencial de uso no melhoramento e na nutrição.

Resumo em Inglês:

ABSTRACT The development of new common bean lines with traits that meet consumer preference increases their probability of use as food. The objectives of this work were to evaluate the genetic variability of common bean lines and cultivars for grain quality traits and mineral concentration and to select superior lines using the rank-sum index with differentiated economic weights. The experiments were carried out in two growing seasons to evaluate 17 common bean genotypes. The ten grain quality traits and the concentration of seven minerals were determined in raw grains. A significant effect for genotype was observed for 15 traits and a significant genotype x environment interaction was found for 14 traits. High heritability (≥ 60.00%) and genetic gain estimates favorable to the objectives of selection of superior light-and dark-grain common bean lines for most of grain quality traits and mineral concentration were obtained. The common bean lines and cultivars show genetic variability for all grain quality traits and mineral concentration, except for copper concentration. Four carioca (LEC 04-16, Linhagem 110, UEM 266 and Pérola) and four black (TB 17-03, SM 1510, BRS Intrépido and Fepagro Triunfo) common bean genotypes are superior for several grain quality traits and have high concentrations of potassium, phosphorus, calcium and iron, showing potential for use in breeding and nutrition.

Resumo em Português:

RESUMO Estabelecer os procedimentos adequados para condução do teste de germinação em espécies florestais é importante para viabilizar a comercialização de lotes de sementes, sobretudo para espécies que ainda não constam nas Instruções Normativas. Objetivou-se com este estudo determinar as condições ideais de temperatura e substrato para a realização do teste de germinação de sementes de Senna siamea, bem como: (i) caracterizar a morfo-fisiologia do estabelecimento da plântula, (ii) o período para a avaliação das plântulas, e (iii) validar a eficiência da metodologia em 10 lotes de sementes. O delineamento utilizado foi inteiramente ao acaso em arranjo fatorial 2 x 2 (temperaturas x substratos) com 12 repetições de 50 sementes para cada tratamento. Para a avaliação dos diferentes lotes, os dados foram submetidos à análise de variância e as médias comparadas pelo teste de Scott-Knott ao nível de 5% de probabilidade. Avaliou-se o percentual e a velocidade de germinação, primeira contagem, comprimento de plântulas, germinação acumulada, e morfologia de plântulas. Sementes de S. siamea possuem maior potencial germinativo em substrato rolo de papel sob temperaturas de 25 e 30 °C (86% e 87%). A primeira contagem de germinação e avaliação final de plântulas deve ser feita aos 15 e 21 dias após a semeadura, respectivamente. A espécie possui germinação do tipo epígea e suas plântulas são fanerocotiledonares. Observou-se que as condições de execução e avaliação do teste de germinação recomendadas neste estudo são adequadas na avaliação de lotes de sementes de S. siamea.

Resumo em Inglês:

ABSTRACT Establishing the appropriate procedures for conducting germination tests in forest species is important for marketing the seeds, especially species that are not yet included in the relevant Normative Instructions. The aim of this study was to determine the ideal conditions of temperature and substrate to carry out the germination test on seeds of Senna siamea, as well as: (i) to characterise the morpho-physiology of seedling establishment, (ii) the period for seedling evaluation, and (iii) validate the efficiency of the methodology in 10 batches of seeds. The experimental design was completely randomised in a 2 x 2 factorial scheme (temperatures x substrates), with 12 replications of 50 seeds in each treatment. To evaluate the different batches, the data were submitted to analysis of variance, and the mean values compared by the Scott-Knott test at 5% probability. The percentage and speed of germination, first count, seedling length, accumulated germination, and seedling morphology were evaluated. The germination potential of S. siamea seeds is greater on paper-roll substrate at temperatures of 25 °C and 30 °C (86% and 87%). The first germination count and final seedling evaluation should be carried out 15 and 21 days after sowing, respectively. The species has epigeal germination and the seedlings are phanerocotyledonous. It was found that the method for carrying out and evaluating the germination test recommended in this study is suitable for evaluating batches of S. siamea seeds.

Resumo em Português:

RESUMO O uso de sensores de solo tem sido uma alternativa para a redução dos custos com amostragem e análise de solo em laboratório, permitindo a adoção de uma maior densidade amostral. O presente estudo teve como objetivo desenvolver uma plataforma multisensor portátil para solo, com sensores de condutividade elétrica aparente, umidade, temperatura e resistência do solo à penetração. A plataforma multisensor foi desenvolvida com base no computador de placa única BeagleBone Black (BBB). Para os sensores de condutividade elétrica aparente e sensor de umidade, circuitos eletrônicos foram desenvolvidos. Uma célula de carga foi utilizada no sensor de resistência do solo à penetração. Para validação, dados de ECa, umidade e resistência à penetração obtidos utilizando a plataforma multisensor e sensores comerciais foram comparados entre si. Um módulo GNSS (Global Navigation Satellite System) de baixo custo foi utilizado para georreferenciamento dos pontos de coleta de dados. O custo com aquisição dos componentes necessários para montagem da plataforma multisensor foi de US$ 361,94. Para ECa, umidade e resistência à penetração média e máxima a correlação entre os dados obtidos com a plataforma multisensor e com os sensores comerciais foram 0,95; 0,92; 0,90 e 0,91, respectivamente. A forte correlação comprova que a plataforma multisensor desenvolvida tem precisão aceitável. Os mapas gerados com os dados obtidos pelos quatro sensores permitiram caracterizar a variabilidade espacial da condutividade elétrica aparente, umidade, temperatura e resistência do solo à penetração em uma lavoura de café.

Resumo em Inglês:

ABSTRACT Soil sensors are alternatively used to reduce the costs of soil sampling and be able to perform analyses in a laboratory. However, using individual sensors can result in low accuracy because the measured variable may be related to more than one soil characteristics. This study aimed to develop a portable soil multisensor platform with sensors for apparent electrical conductivity, moisture, temperature, and penetration resistance of the soil. The multisensor platform was developed based on a BeagleBone Black (BBB) single-board computer. Electronic circuits have been developed for electrical conductivity and moisture sensors. A load cell was used in the soil-penetration resistance sensor. For validation, the ECa, soil moisture, and penetration resistance data obtained using the multisensor platform and commercial sensors were compared. A low-cost global navigation satellite system module was used to georeference sampling points. The cost of acquiring the components required to assemble the multisensor platform was US$ 361.94. The strong correlation between the data obtained with the multisensor platform and commercial sensors proves that the developed multisensor platform has acceptable accuracy. The spatial variability of the apparent soil electrical conductivity, moisture, temperature, and penetration resistance in a coffee plantation can be characterized by the generated maps from the data obtained by the four sensors.

Resumo em Português:

RESUMO O mercado consumidor tem ampliado sua busca por alimentos que agreguem atributos sensoriais, nutricionais e bioativos, o que traz os cogumelos comestíveis a uma posição de destaque. No entanto, sua cadeia produtiva ainda apresenta deficiências na prevenção de danos mecânicos, contaminação microbiológica, perecibilidade e perda de massa ao longo do armazenamento, fatores muito associados ao uso de embalagens pouco adequadas ao produto. O objetivo deste trabalho foi avaliar se diferentes configurações de embalagens, associadas à aplicação de cobertura comestível de gel de Aloe vera, preservam a vida útil e segurança de cogumelos shiitake frescos ao longo de seu armazenamento, sobretudo em substituição à embalagem padrão. O experimento foi conduzido com cogumelos shiitake frescos, com delineamento inteiramente casualizado em esquema fatorial 3 x 2 x 4, sendo 3 configurações de embalagem (EPS PVC, EPS PVC perfurado, Xtend), 2 condições de cobertura (com e sem cobertura de gel de Aloe vera), 4 período de armazenamento (0, 3, 7 e 10 dias), com 4 repetições. Em cada período de armazenagem avaliou-se perda de massa, aparência visual, concentração de CO2 na embalagem e avaliações microbiológicas. Constatou-se que o uso de cobertura de Aloe vera em cogumelos shiitake preserva seus atributos de qualidade e promove a segurança do alimento através da ação antimicrobiana, prolongando sua vida útil. Embalagens Xtend® mostram-se potencialmente adequadas para substituir embalagens EPS PVC na comercialização de cogumelos frescos, reduzindo a perda de massa e preservando qualidade e segurança do alimento.

Resumo em Inglês:

ABSTRACT The consumer market has expanded its search for foods combining sensory, nutritional, and bioactive attributes, which puts edible mushrooms in evidence. However, their production chain still has deficiencies to prevent mechanical damage, microbiological contamination, perishability, and weight loss during storage, factors closely associated with unsuitable packaging of the product. This study aimed to evaluate whether different packaging configurations, associated with the application of edible Aloe vera gel coating, preserve shelf life and safety of fresh shiitake mushrooms throughout their storage, especially as a replacement for standard packaging. The experiment was conducted with fresh shiitake mushrooms, with a completely randomized design in a 3 x 2 x 4 factorial scheme, with three packaging configurations (EPS PVC, EPS PVC perforated, Xtend®), 2 coating conditions (with and without Aloe vera gel coating), four storage times (0, 3, 7 and 10 days), with four repetitions. For each storage time, weight loss, visual aspect, CO2 concentration in the package, and microbiological evaluations were assessed. In conclusion, use of Aloe vera coating on shiitake mushrooms preserves their quality attributes and promotes food safety through antimicrobial action, extending their shelf life. Xtend® packaging is potentially suitable to replace EPS PVC packaging in the sale of fresh mushrooms, reducing weight loss and preserving food quality and safety.

Resumo em Português:

RESUMO A escassez de água se tornou uma preocupação para muitos países; um sistema de irrigação adequado é essencial para o uso racional da água. Portanto, são necessárias informações sobre a dinâmica da água no volume de solo molhado. Investigações de campo e análises de laboratório podem medir as dimensões do volume de solo molhado, mas são demoradas e onerosas. Modelos matemáticos podem ser usados para obter tais informações com base nas propriedades do solo, dentre os modelos mais utilizados no HYDRUS-2D. Nesse sentido, objetiva-se simular o movimento da água em um perfil de solo arenoso utilizando o modelo HYDRUS-2D para gotejadores de subsuperfície em diferentes espaçamentos, profundidades e vazões. Inicialmente, foi realizado um teste para validar HYDRUS-2D para o solo Neossolo Quartzarênico. Após a validação, foram feitas simulações para gotejadores, dispostos da seguinte forma: espaçamentos de 0,30, 0,40 e 0,50 m; profundidades de 0,20, 0,25 e 0,30 m; e taxas de fluxo de 1,0 e 1,6 L h-1. Em todas as simulações, foram realizadas dez aplicações de 1 L de água. As simulações mostraram que o espaçamento, profundidade e vazão de 0,40 m, 0,20 m e 1,6 L h-1, respectivamente, apresentaram os melhores desempenhos. Nessa configuração, o volume de solo úmido permaneceu em profundidade adequada em um cenário de raiz de cana e próximo à superfície, evitando custos econômicos e ambientais devido a perdas de água por lixiviação.

Resumo em Inglês:

ABSTRACT Water scarcity has become a concern for many countries; a proper irrigation system is essential for rational water use. Therefore, information on water dynamics within the wetted soil is necessary. Field investigations and laboratory analyses can measure wetted soil volume dimensions, but these are time-consuming and costly. Mathematical models can also be used to obtain such information based on soil physical-hydraulic properties, among the most used models in HYDRUS-2D. In this sense, we aimed to simulate water movement in a sandy soil profile using the HYDRUS-2D model for subsurface drippers at different spacings, depths, and flows rates. Initially, a greenhouse test was carried out to validate HYDRUS-2D for the soil Psamment (Ferralic Arenosol). After validation, simulations for drippers were arranged as follows: spacings of 0.30, 0.40, and 0.50 m; depths of 0.20, 0.25, and 0.30 m; and flow rates of 1.0 and 1.6 L h-1. In all simulations, ten applications of 1 L of water were carried out. Simulations showed that the dripper spacing, depth, and flow rate of 0.40 m, 0.20 m, and 1.6 L h-1 presented the best performance. In this configuration, wetted soil volume remained at an adequate depth in a scenario of sugarcane root and near the surface, avoiding economic and environmental costs due to water losses to deeper soil layers.

Resumo em Português:

RESUMO A atividade de experimentação agrícola pode exigir alto orçamento e longos períodos de tempo para obtenção de dados. Devido às características de produção, os processos decisórios em unidades agroindustriais que utilizam a cana-de-açúcar como matéria-prima devem ser otimizados. Nesse cenário, a modelagem de sistemas operacionais que utilizam tecnologia embarcada como automação agrícola possibilita a otimização da tomada de decisões e influencia o desempenho operacional e os custos. Este artigo apresenta um modelo de recebimento e processamento de cana-de-açúcar baseado em sua capacidade de colheita, considerando o índice de colheita e a capacidade nominal da colhedora. A análise de sensibilidade permite a avaliação de potenciais infratores e a realocação de ativos, otimizando recursos e garantindo a operação da planta. Essa análise também possibilita novas possibilidades, como colher em diferentes espaçamentos entre linhas e colheita simultânea de linhas.

Resumo em Inglês:

ABSTRACT The activity of agricultural experimentation may require high budget and long periods of time for obtaining data. Due to production features, decision-making processes within agro-industrial mills that use sugarcane as raw material must be optimized. In this scenario, modeling operating systems that use embedded technology as agricultural automation enables the optimization of decision-making and influences operational performance and costs. This article presents a model for receiving and processing sugarcane based on its harvesting capacity, considering the harvestability index and the nominal capacity of the harvester. Sensitivity analysis enables the assessment of potential offenders and the reallocation of assets, thus optimizing resources and ensuring plant operation. This analysis also enables new possibilities, such as harvesting under different row spacings and harvesting simultaneously different rows.

Resumo em Português:

RESUMO Os objetivos deste trabalho foram determinar o tamanho ótimo de parcela (Xo) para avaliar a produtividade de matéria fresca de trigo (Triticum aestivum L.) e verificar se Xo difere entre três métodos de determinação. Foram conduzidos cinco ensaios de uniformidade. Os ensaios 1 e 2 foram conduzidos, respectivamente, com as cultivares TBIO Sossego e TBIO Toruk, ambas semeadas em 03 de agosto de 2018. Os ensaios 3, 4 e 5 foram conduzidos com a cultivar TBIO Audaz semeada, respectivamente, em 07 de junho de 2019, 27 de junho de 2019 e 18 de julho de 2019. Foi avaliada a produtividade de matéria fresca em 540 unidades experimentais básicas (UEB) de 1 m × 1 m (108 UEB por ensaio). A UEB foi formada por cinco fileiras de 1,0 m de comprimento, espaçadas 0,20 m entre fileiras, totalizando 1,0 m2. Foi determinado o tamanho ótimo de parcela por meio dos métodos da curvatura máxima modificado, do modelo linear de resposta com platô e do modelo quadrático de resposta com platô. O tamanho ótimo de parcela difere entre os métodos e decresce na seguinte ordem: modelo quadrático de resposta com platô (15,78 m2), modelo linear de resposta com platô (7,11 m2) e curvatura máxima modificado (2,56 m2). O tamanho ótimo de parcela para avaliar a produtividade de matéria fresca de trigo é 7,11 m2 e a precisão experimental estabiliza a partir desse tamanho.

Resumo em Inglês:

ABSTRACT The objectives of this study were to determine the optimal plot size (Xo) to evaluate the fresh matter productivity of wheat (Triticum aestivum L.) and check whether Xo differs between three determination methods. Five uniformity trials were carried out. Trials 1 and 2 were carried out, respectively, with the cultivars TBIO Sossego and TBIO Toruk, both sown on August 3, 2018. Trials 3, 4 and 5 were carried out with the cultivar TBIO Audaz, sown, respectively, on June 7, 2019, June 27, 2019 and July 18, 2019. Fresh matter productivity was evaluated in 540 basic experimental units (BEU) of 1 m × 1 m (108 BEU per trial). The BEU was formed by five rows of 1.0 m in length, spaced 0.20 m apart, totaling 1.0 m2. The optimal plot size was determined using the methods of modified maximum curvature, linear response and plateau model and quadratic response and plateau model. The optimal plot size differs between the methods and decreases in the following order: quadratic response and plateau model (15.78 m2), linear response and plateau model (7.11 m2) and modified maximum curvature (2.56 m2). The optimal plot size to evaluate the fresh matter productivity of wheat is 7.11 m2 and the experimental precision stabilizes from this size on.

Resumo em Português:

RESUMO Com a descoberta recente de cinco novas espécies do gênero Monosporascus, gênero fúngico envolvido na “podridão das raízes por Monosporascus e declínio das ramas”, estudos de patogenicidade tem se tornado importante para conhecer o impacto dessas novas espécies em plantas cultivadas, principalmente sobre espécies vegetais utilizadas como alternativa de rotação de culturas. Este estudo teve como objetivo avaliar a patogenicidade de Monosporascus spp. em culturas não-cucurbitáceas. Os ensaios foram realizados em duplicata, em casa-de-vegetação, utilizando o delineamento inteiramente casualizado, tendo como tratamentos: um isolado de cada espécie de Monosporascus (M. brasiliensis, M. caatinguensis, M. cannonballus, M. mossoroensis, M. nordestinus e M. semiaridus) e a testemunha absoluta, e cinco culturas (feijão-caupi, feijão-de-porco, milho sorgo e pimentão). Sementes destas culturas foram semeadas em vasos contendo solo + Tropstrato HT® (proporção 2:1, v / v), previamente inoculados com sementes de trigo colonizadas com as espécies de Monosporascus. Após 50 dias da semeadura, as plantas foram avaliadas quanto a incidência, severidade da doença, comprimento da parte aérea e das raízes, peso fresco e seco da parte aérea e raízes. Todas as espécies de Monosporascus induziram danos em feijão-caupi e pimentão, sendo M. cannonballus a espécie mais agressiva. O milho, feijão-de-porco e sorgo apresentaram poucos ou nenhum sintoma da doença, podendo ser indicadas como culturas alternativas a serem usadas em rotação de cultivo com cucurbitáceas. Estudos com um maior número de isolados e cultivares para cada cultura testada neste estudo deverão ser realizados para fortalecer os dados obtidos.

Resumo em Inglês:

ABSTRACT With the recent discovery of five new species of the Monosporascus genus, a fungal genus involved in “Monosporascus root rot and vine decline,” pathogenicity studies have become important to understand the impact of these new species on cultivated plants, mainly on plant species used as an alternative for crop rotation. This study aimed to evaluate the pathogenicity of Monosporascus spp. in non-cucurbitaceous cultures. The tests were carried out in duplicate in a greenhouse in a completely randomized design, with the treatments: One isolate of each species of Monosporascus (M. brasiliensis, M. caatinguensis, M. cannonballus, M. mossoroensis, M. nordestinus, and M. semiaridus) and the absolute control, and five cultures (cowpea, jack bean, corn, sorghum, and bell pepper). Seeds of these cultures were sown in pots containing soil + Tropstrate HT® (ratio 2:1, v / v), previously inoculated with wheat seeds colonized with the species of Monosporascus. After 50 days of sowing, plants were evaluated for incidence, disease severity, length of shoot and roots, fresh and dry weight of shoots and roots. All inoculated Monosporascus species were able to induce damage in cowpea and bell pepper cultures, with M. cannonballus being the most aggressive. Corn, jack beans, and sorghum presented few or no symptoms of the disease and may be indicated as alternative cultures to be used in crop rotation with cucurbits. Studies with a greater number of isolates and cultivars for each culture tested in this study should be carried out to strengthen the data obtained.

Resumo em Português:

RESUMO O Clima é um fator determinante na produção agrícola e as mudanças climáticas podem afetar esta produtividade. Assim, este estudo tem como objetivo analisar as consequências das mudanças climáticas na dinâmica da água no solo e do crescimento da soja no sul do Brasil. Foram criados cenários para condições de aumento de temperatura de 2 ºC, redução de 20% e aumento de 50% nas taxas de precipitação, representando cenários quentes, secos e úmidos, respectivamente. Os forçamentos atmosféricos gerados foram utilizados como dados de entrada para a versão agrícola do modelo de Simulação Integrada da Biosfera (Agro-IBIS) e simulações foram executadas para uma estação de cultivo de soja no noroeste do Rio Grande do Sul, Brasil. Analisaram-se as seguintes variáveis estimadas pelo Agro-IBIS: umidade do solo, índice de área foliar (LAI) da soja, evaporação e transpiração. Os resultados mostraram que as mudanças climáticas projetadas pelas simulações influenciam o crescimento da soja na área de estudo. Ao aumentar a temperatura em 2 °C, o modelo Agro-IBIS indicou a ocorrência de ciclos de crescimento de safra mais curtos e resultados ainda mais impactantes no LAI, com redução de 70% nos valores mais altos. Além disso, o aumento de 50% na taxa de precipitação mostrou efeitos positivos na agricultura, indicados pelo aumento do LAI no período reprodutivo. Por outro lado, a redução de 20% na precipitação tem efeito negativo, pois expõe a cultura a condições de déficit hídrico, impactando a umidade do solo e diminuindo o LAI. A evaporação do solo também é intensificada com o aumento das temperaturas devido à maior demanda evaporativa da atmosfera e um declínio significativo do LAI. A transpiração para o cenário quente é mais fortemente afetada durante o estádio de crescimento vegetativo e a senescência das folhas.

Resumo em Inglês:

ABSTRACT Climate is a determining factor in agricultural production and climate change can affect this productivity. This, study aims to analyze the consequences of climatic change in the soil water dynamic and growth soybean in Southern Brazil. Scenarios were created for conditions of a 2 ºC temperature increase, a 20% reduction, and a 50% increase in precipitation rates, representing hot, dry and wet scenarios, respectively. The atmospheric forcing generated were used as input data for the agricultural version of the Integrated Biosphere Simulator model (Agro-IBIS) and simulations were carried out for a soybean growing season in the northwestern Rio Grande do Sul, Brazil. The following variables estimated by Agro-IBIS were analyzed: soil moisture, soybean leaf area index, evaporation, and transpiration. The results showed that the climatic changes projected by the simulations influence soybean growth in the study area. By increasing the temperature in 2 °C, the Agro-IBIS model indicated the occurrence of shorter crop growth cycles and even more impactful results on the leaf area index, with a 70% reduction in the highest values. Furthermore, a 50% increase in precipitation rate showed positive effects on agriculture, indicated by increased LAI in the reproductive period. On the other hand, a 20% reduction in precipitation has a negative effect, as it exposes the crop to water deficit conditions, impacting soil moisture and decreasing LAI. The soil evaporation is also intensified with increased temperatures due to the higher evaporative demand of the atmosphere and a significant decline in LAI. The transpiration for the hot scenario is more strongly impacted during the vegetative growth stage and leaf senescence.

Resumo em Português:

Resumo Para avaliar quantitativamente o efeito da altura do restolho e da cobertura morta na resistência do solo à erosão do vento em terras cultivadas protegidas de castanheiros sob diferentes condições de velocidade do vento, foram realizados testes de conservação e lavoura convencional no planalto da Mongólia, China, utilizando um túnel móvel de vento de erosão do vento. Os solos de castanha são um tipo de solo em ecossistemas semi-áridos frágeis que são suscetíveis à desertificação após a erosão pelo vento e são encontrados principalmente na Ásia Central e no continente norte-americano. Os resultados mostram que a erosão do solo na lavoura de conservação é menor do que a lavoura convencional em diferentes velocidades de vento. A resistência da lavoura de conservação à erosão do solo pelo vento aumenta com o aumento da altura do restolho e da cobertura. Com uma altura do restolho de 300 mm e uma cobertura de 50%, a eficiência média de resistência da lavoura de conservação à erosão pelo vento é de 74,82%, evitando efetivamente a erosão pelo vento dos solos agrícolas.

Resumo em Inglês:

ABSTRACT >To quantitatively evaluate the effect of stubble height and mulching on soil resistance to wind erosion in protected cultivated chestnut soil farmland under different wind speed conditions, tests were carried out on conservation and conventional tillage in Mongolian Plateau, China, using a mobile wind erosion wind tunnel. Chestnut soils were a soil type in fragile semi-arid ecosystems that were susceptible to desertification following wind erosion and were found mainly in Central Asia and the North American continent. The results show that soil erosion on conservation tillage was lower than conventional tillage at different wind speeds. The resistance of conservation tillage to soil wind erosion increases with increasing stubble height and cover. At a stubble height of 300 mm and 50% cover, conservation tillage's average wind erosion resistance efficiency was 74.82%, effectively preventing wind erosion of agricultural soils.

Resumo em Português:

RESUMO Em um programa de melhoramento genético, a estimativa do progresso genético ao longo dos anos fornece uma visão ampla do programa, bem como bases para uma ótima tomada de decisão. Nesse sentido, o presente estudo se propõe a estimar o progresso genético de 54 cultivares de soja lançadas para o Centro-Oeste brasileiro entre os anos de 2000 e 2017. Dois experimentos foram conduzidos na safra 2017/18. Foram avaliados o rendimento de grãos (RG), grupo de maturidade (GM), peso de 100 sementes (P100), número de vagens por planta (NVP), número de sementes por vagem (NSP) e altura de planta (AP). O progresso genético foi estimado pela metodologia direta e por regressão linear. De acordo com o método direto, o progresso genético anual médio foi positivo para GR (1,92%), P100 (2,69%), NVP (2,31%), NSP (1,10%) e AP (0,32%), mas negativo para GM (- 0,44%). Os resultados obtidos por ambas as metodologias concordam com os aumentos obtidos para RG e P100 e decréscimos para GM.

Resumo em Inglês:

ABSTRACT In a breeding program, the estimation of genetic progress over the years provides a broad view of the program as well as grounds for optimal decision-making. In this respect, the present study proposes to estimate the genetic progress of 54 soybean cultivars released to the Brazilian Midwest between the years 2000 and 2017. Two experiments were conducted during the 2017/18 crop year. Grain yield (GY), maturity group (MG), 100-seed weight (100SW), number of pods per plant (NPP), number of seeds per pod (NSP) and plant height (PH) were evaluated. Genetic progress was estimated by the direct methodology and by linear regression. According to the direct method, the average annual genetic progress was positive for GY (1.92%), 100SW (2.69%), NPP (2.31%), NSP (1.10%) and PH (0.32%), but negative for MG (-0.44%). The results obtained using both methodologies agree on the obtained increases for GY and 100SW and the decreases for MG.

Resumo em Português:

RESUMO A utilização agrícola de fontes alternativas de água de qualidade inferior, tais como o reuso de águas de esgotos de origem doméstica, surge como opção para ampliar a disponibilidade hídrica, além de proporcionar o reaproveitamento de nutrientes e matéria orgânica, auxiliando na manutenção da fertilidade e produtividade do solo. Nesse contexto objetivou-se com este trabalho avaliar o crescimento, a produtividade e a nutrição do capim elefante irrigado com diferentes combinações de aplicação do esgoto doméstico tratado e água de poço. O delineamento experimental utilizado foi em blocos ao acaso, com seis tratamentos e quatro repetições, contendo 10 plantas em cada parcela. Os tratamentos consistiram em cinco combinações de aplicação do efluente doméstico tratado (EDT) e água de poço (AP): T1 (100% AP), T2 (25% EDT + 75% AP), T3 (50% EDT + 50% AP), T4 (75% EDT + 25% AP), T5 (100% EDT) e um tratamento adicional (T6) irrigado 100% com água de poço + adubação mineral (N-P-K) recomendada para o capim elefante. As variáveis analisadas foram: número de folhas, diâmetro do colmo, número de perfilhos, altura da planta, área foliar, massa fresca e seca da folha e do colmo, produtividades de massa fresca e seca, e o teor de macronutrientes na parte aérea da planta. Os tratamentos com maiores quantidades de EDT aplicado na irrigação foram os que mais se aproximaram das obtidas no tratamento cultivado convencionalmente, sendo os tratamentos com 50% ou mais de EDT estatisticamente iguais ao tratamento com cultivo convencional pelo teste de Tukey (p < 0,05).

Resumo em Inglês:

ABSTRACT The agricultural use of alternative water sources of inferior quality, such as reusing the water from domestic sewage, is seen as one way of increasing water availability, in addition to allowing the reuse of nutrients and organic matter, thereby helping to maintain the fertility and productivity of the soil. The aim of this study, therefore, was to evaluate growth, productivity and nutrition in elephant grass irrigated with different combinations of treated domestic effluent and well water. The experimental design was of randomised blocks, with six treatments and four replications, containing 10 plants in each plot. The treatments comprised five combinations of treated domestic effluent (TDE) and well water (WW): T1 (100% WW), T2 (25% TDE + 75% WW), T3 (50% TDE + 50% WW), T4 (75% TDE + 25% WW), T5 (100% TDE), and an additional treatment (T6) of 100% well water + a mineral fertiliser (NPK) recommended for elephant grass. The following variables were analysed: number of leaves, stem diameter, number of tillers, plant height, leaf area, fresh and dry weight of the leaves and stems, fresh and dry weight production, and the macronutrient content of the aerial part of the plant. The treatments applying the greatest levels of TDE had the closest mean values to those obtained under the conventional treatment, while the treatments applying 50% or more TDE were statistically equal by Tukey’s test (p < 0.05) to the conventional treatment.

Resumo em Português:

RESUMO A aplicação de herbicidas dessecantes na cultura do crambe é importante para produção de sementes de qualidade. Objetivou-se avaliar o efeito de herbicidas dessecantes e diferentes volumes de calda aplicadas em plantas de crambe, cultivar FMS Brilhante, na fase de pré-colheita sobre a produtividade e qualidade de sementes. O delineamento experimental foi em blocos casualizados em esquema fatorial 2 x 5, sendo dois herbicidas dessecantes (Glyphosate – Roundup Original 360 g L-1 e Diquat – Reglone 200 g L-1) e cinco volumes de calda (0,0; 0,5; 1,0; 1,5; e 2,0 L ha-1), com quatro repetições. A aplicação dos dessecantes ocorreu aos 74 dias após a semeadura, baseada no estádio de maturação das sementes, verificado a partir da observação visual da porcentagem de sementes marrons (80%). Após a colheita, as sementes foram beneficiadas e avaliadas quanto ao teor de água, peso de mil sementes, produtividade, teor de óleo, germinação e vigor (primeira contagem de germinação, índice de velocidade de emergência, envelhecimento acelerado e condutividade elétrica). A dessecação na fase de pré-colheita das plantas de crambe com o herbicida Diquat, nos volumes de calda entre 1,3 e 1,5 L ha-1, proporcionou sementes de melhor qualidade fisiológica. O vigor das sementes foi reduzido pela dessecação das plantas com Glyphosate. A produtividade da cultura não foi afetada pelos herbicidas e nem pelos diferentes volumes de calda.

Resumo em Inglês:

ABSTRACT The application of burndown herbicides to crambe crops is important for production of quality seeds. The objective of this work was to evaluate the effect of burndown herbicides applied at pre-harvest, using different spray volumes, on seed yield and quality of crambe plants (Crambe abyssinica cv. FMS Brilhante). A randomized block experimental design was used, with four replications, in a 2 × 5 factorial arrangement consisted of two burndown herbicides [glyphosate (Roundup Original 360 g L-1) and diquat (Reglone 200 g L-1)] and five spray volumes (0.0, 0.5, 1.0, 1.5, and 2.0 L ha-1). The burndown herbicides were applied at 74 days after sowing, when the plants presented 80% brown seeds, based on visual evaluation of the seed maturation stage. After harvest, the seeds were processed and evaluated for water content, one-thousand seed weight, seed yield, oil contents, germination, and vigor (first germination counting, emergence speed index, accelerated aging, and electrical conductivity). The pre-harvest desiccation of crambe with the herbicide diquat, using spray volumes between 1.3 and 1.5 L ha-1, resulted in seeds with better physiological quality. The seed vigor was low when using desiccation of plants with glyphosate. The crop yield was not affected by the herbicides nor by the different spray volumes.

Resumo em Português:

RESUMO O objetivo do presente trabalho foi avaliar a influência de variáveis ambientais na interação entre genótipos e ambientes e identificar genótipos adaptados e estáveis para a produção de sementes. Vinte e uma cultivares foram avaliadas em blocos ao acaso com quatro repetições nos anos de 2016, 2017 e 2018 no semiárido nordestino do Brasil, para rendimento de sementes e teor de óleo. Metodologias de regressão fatorial e análise de componentes principais foram utilizadas com previsões da soma dos efeitos genotípicos e a interação para quantificar o papel de cinco covariáveis ambientais na interação genótipo x ambiente; o Método da Média Harmônica de Desempenho Relativo de Valores Genotípicos foi usado para identificar genótipos adaptados e estáveis. O modelo biplot de covariância é útil para relacionar fatores ambientais importantes e indicar seu efeito relativo no rendimento de sementes e no teor de óleo. A precipitação, a umidade relativa e a temperatura máxima contribuem positivamente para aumentar o teor de óleo, enquanto a temperatura mínima e a radiação solar o reduzem. Dentro dos limites do trabalho, a temperatura máxima influencia positivamente a produção de grãos enquanto a mínima a reduz. Os genótipos mais estáveis e adaptados para rendimento de sementes de grãos e teor de óleo são BMX OPUS IPRO, P 98Y70 RR, BRS 333 RR, BRS 9280 RR, M 8644 IPRO, M 8372 IPRO e ST 920 RR.

Resumo em Inglês:

ABSTRACT The objective of the present work was to evaluate the influence of environmental variables on the interaction between genotypes and environments and to identify adapted and stable genotypes for grain seed yield. Twenty-one cultivars were evaluated in randomized blocks with four replications in the years 2016, 2017, and 2018 in the northeastern semi-arid region of Brazil, for seed yield and oil content. Factor regression methodologies and principal component analysis were used with predictions of the sum of the genotypic effects and the interaction to quantify the role of five environmental covariates in the genotype x environment interaction; the Harmonic Mean Method of Relative Performance of Genotypic Values was used for identifying adapted and stable genotypes. The covariance biplot model is useful for relating important environmental factors and indicating their relative effect on seed yield and oil content. Rainfall, relative humidity and maximum temperature contribute positively to increasing oil content while minimum temperature and solar radiation reduce it. Within the limits of the work, the maximum temperature positively influences grain production while the minimum reduces it. The most stable genotypes and those adapted for grain seed yield and oil content are BMX OPUS IPRO, P 98Y70 RR, BRS 333 RR, BRS 9280 RR, M 8644 IPRO, M 8372 IPRO, and ST 920 RR.

Resumo em Português:

RESUMO A co mpactação é um dos principais fatores físicos do solo que afetam o desenvolvimento vegetal. A pesquisa objetivou avaliar o desenvolvimento aéreo e radicular de plantas de inverno cultivadas em solos de diferentes granulometrias e submetidos a diferentes graus de compactação do solo (GCS). O experimento foi conduzido em casa de vegetação na Universidade Estadual de Ponta Grossa. Foram testados o trigo (Triticum aestivum) e o consórcio de aveia preta (Avena strigosa) + nabo forrageiro (Raphanus sativus) em Cambissolo franco arenoso e Latossolo franco argiloso nos GCS de 85, 90, 95 e 100% da densidade máxima, no delineamento experimental inteiramente casualizado com quatro repetições. Cada parcela era formada por uma coluna de PVC com diâmetro de 0,1 m e altura de 0,2 m, composta por três anéis sobrepostos com altura de 0,08, 0,04 e 0,08 m respectivamente na porção superior, intermediária e inferior. A camada compactada foi a subsuperficial (0,08-0,12 m), correspondente ao anel intermediário. O consórcio de espécies apresentou massa seca de raízes (MSR) 28,5% superior ao trigo na camada subsuperficial compactada. A MSR total diminuiu 32% com o aumento de 85 para 100% no GCS, sendo a camada compactada (0,08-0,12 m) e a camada abaixo dela (0,12-0,2 m) as mais afetadas, com redução de 45,2 e 53%, respectivamente. Considerando as condições deste estudo, o qual avaliou solos sem restrições hídricas e químicas para as plantas, a massa seca de parte aérea (MSA) foi menos afetada que as raízes, pois diminuiu 12% com o aumento de 85 para 100% no GCS. Não houve diferença entre o tipo de solo sobre a resposta das culturas devido a variação no GCS.

Resumo em Inglês:

ABSTRACT Compaction is one of the main physical factors of the soil to affect plant development. The aim of this study was to evaluate root and shoot development in winter plants grown in soils of different textures under varying degrees of soil compaction (DSC). The experiment was conducted in a greenhouse of the State University of Ponta Grossa, in the south of Brazil. Wheat (Triticum aestivum) and an intercropping system of black oats (Avena strigosa) and forage turnip (Raphanus sativus) were tested in a sandy loam Cambisol and a clayey loam Latosol under a DSC of 85%, 90%, 95% and 100% of the maximum bulk density in a completely randomised design with four replications. Each plot consisted of one PVC column, 0.1 m in diameter and 0.2 m in height, comprising three cylinders placed one on top of the other, with a respective height of 0.08, 0.04 and 0.08 m. The sub-surface layer (0.08-0.12 m) was compacted, and corresponded to the middle cylinder. In t he compacted sub-surface layer, the intercropped black oats and forage turnip presented 28.5% more root dry matter (RDM) than did the wheat. The total RDM decreased by 32% for an increase of 85% to 100% in the DSC, where both the compacted sub-surface layer (0.08-0.12 m) and the layer below that (0.12-0.2 m) were most affected, with a reduction of 45.2% and 53%, respectively. Considering the conditions of this study, which evaluated soils that offer no water or chemical restrictions on the plants, shoot dry matter (SDM) was less affected than the roots, decreasing by 12% for an increase of 85% to 100% in the DSC. There was no difference between the types of soil on crop response due to the variation in the DSC.

Resumo em Português:

RESUMO O objetivo do estudo é oferecer um resgate histórico do conjunto de ações em governança do solo implementados no estado do Paraná, desde a década de 1970, que vão dos trabalhos desenvolvidos pelos institutos de pesquisa, aos programas governamentais. São ações que possibilitaram o desenvolvimento de tecnologias e a ampla adoção de práticas conservacionistas pelos produtores. Além de indicar os fatores que deram base para a retomada das discussões, em período recente, sobre conservação do solo e da água. Como fontes de informações foram utilizados relatórios de pesquisa e dos programas desenvolvidos no Paraná, empregando o método de revisão histórico-bibliográfica. Verificou-se que foi executado um amplo trabalho de planificação de uso, manejo e conservação dos recursos naturais no Paraná, denotando a construção de uma governança forte em solo e água. Destacam-se no Paraná as ações realizadas em microbacias hidrográficas, pelo pioneirismo do seu enfoque, duração e dimensões, e o desenvolvimento do Sistema Plantio Direto. Contudo, nem tudo foi sempre linear nessa evolução, uma vez que com o passar do tempo foi se constituindo a falsa percepção – principalmente entre os produtores – de que o problema da erosão já estava solucionado. Em consequência disso, muitos agricultores passaram a negligenciar práticas de conservação do solo com uso de terraços, o abandono das operações agrícolas em nível, bem como a rotação de culturas. Tais condutas reavivaram problemas conhecidos e graves de degradação, acentuando os processos de perdas de solo e água pela erosão, e seus prejuízos associados. Neste contexto, descreve-se os instrumentos que estão sendo utilizados em uma nova estratégia paranaense para a retomada de uma efetiva governança do solo, por meio de políticas públicas e de parcerias público-privadas na promoção da conservação de solos e água.

Resumo em Inglês:

ABSTRACT This study is a historical overview of land governance initiatives implemented in Parana state, Brazil, since the 1970s, ranging from the work carried out by research institutes to government-sponsored programs. These initiatives encouraged the development of technologies and farmers’ widespread adoption of conservation practices. Furthermore, they highlight the factors that brought soil and water conservation to the forefront in discussions on agriculture. This bibliographic review was based on information in research papers and programs developed in Parana. We show that extensive work on management planning and natural resource conservation was undertaken in Parana to strengthen soil governance. The initiatives implemented in watersheds and the development of the no-tillage system represent considerable achievements. However, it was not always that straightforward. As time progressed, the false perception – mainly among farmers – that the erosion problem had been solved led many farmers to neglect soil conservation practices, and in some cases, to abandon agricultural terracing, contour farming, and crop rotation. This resulted in a resurgence of problems related to environmental degradation, aggravating erosion and causing losses of soil and water, with the concomitant environmental damage. In this regard, we describe the means deployed in a new strategy to stimulate a resurgence of effective soil governance based on public policies and public-private partnerships to promote soil and water conservation.

Resumo em Português:

RESUMO O modelo da zona agroecológica (MZA-FAO) é utilizado para descrever cenários agrícolas e o impacto do risco climático sobre as culturas e, quando adaptado, pode ser utilizado para simular o rendimento de espécies forrageiras em condições adversas. Objetivou-se testar o desempenho do modelo MZA-FAO para simular o rendimento do capim Urochloa humidicola no Mato Grosso. O modelo foi adaptado para duas localidades que apresentam condições edafoclimáticas distintas, com dados de dois experimentos (E1 e E2). Foram analisadas as variáveis morfofisiológicas das pastagens, físico-hídricas do solo e dados meteorológicos do período experimental. A calibração do modelo baseou-se nas alterações do coeficiente de sensibilidade da cultura ao déficit hídrico (Ky) e na minimização dos desvios entre dados simulados e observados. O modelo apresentou desempenho satisfatório para as duas regiões analisadas. No experimento E1, o RMSE foi de 29,86% (aceitável) e o índice c de 0,86 (ótimo) na fase de calibração, mantendo os mesmos resultados na validação. No E2, houve uma melhoria no desempenho do modelo, com RMSE e índice c passando de 30,74% (pobre) e 0,84 (muito bom) na calibração, para 17,50% (boa) e 0,92 (ótimo) na etapa de validação, respectivamente. O modelo MZA-FAO adaptado para o capim Urochloa humidicola, pode ser utilizado com boa precisão para simular o rendimento de forragem dessa forrageira na região sul de Mato Grosso.

Resumo em Inglês:

ABSTRACT The agro-ecological zone model (AZM-FAO) is used to describe agricultural scenarios and the impact of climate risk on crops and, when adapted, can be used to simulate the yield of forage species under adverse conditions. The study aimed to test the performance of the AZM-FAO model to simulate the yield of Urochloa humidicola grass in Mato Grosso. The model was adapted for two locations with different soil and climate conditions, with data from two experiments (E1 and E2). The morphophysiological variables of the pastures, the physical-hydric variables of the soil, and the meteorological data of the experimental period were analyzed. The model calibration was based on changes in the yield response coefficient to water (Ky) and the minimization of deviations between simulated and observed data. The model presented a satisfactory performance for the two analyzed locations. In experiment E1, the RMSE was 29.86% (acceptable), and the c index was 0.86 (optimal) in the calibration phase, maintaining the same results in the validation. In E2, there was an improvement in the performance of the model, with RMSE and c index going from 30.74% (poor) and 0.84 (very good) in the calibration to 17.50% (good) and 0.92 (very good) in the validation step, respectively. The AZM-FAO model adapted for Urochloa humidicola grass can be used with good accuracy to simulate the forage yield of this forage in the southern region of Mato Grosso.

Resumo em Português:

RESUMO A medida do potencial propagativo de uma variedade, considerando a micropropagação para a obtenção das mudas, tem tido pouca atenção dos pesquisadores. O uso de técnicas estatísticas pouco usuais, a exemplo da taxa de crescimento geométrico e regressão exponencial, pode produzir informação relevante para o planejamento e aplicação nos subcultivos baseado no comportamento in vitro, o que poderá indicar a necessidade de melhorar o protocolo, assim como a influência dos ensaios de intervalos e repicagens precisa ser mais bem compreendido. O objetivo do trabalho foi avaliar os efeitos de três diferentes intervalos entre subcultivos no potencial propagativo de cultivares comerciais de abacaxizeiros visando otimização dos protocolos de micropropagação e no planejamento para a produção de mudas em escala comercial. Foram utilizadas gemas axilares das cultivares Perola, BRS Imperial e Smooth Cayenne para o estabelecimento e multiplicação in vitro, em ensaios com 30, 45 e 60 dias como intervalo de repicagem em seis subcultivos. A cultivar BRS Imperial apresentou os melhores resultados no ensaio de 30 dias. Embora o número de brotos cresça com o avanço dos subcultivos, há maior queda no potencial propagativo. Maiores intervalos de subcultivos apresentam menor produção de brotos e potencial propagativo, como ficou demostrado pela taxa de crescimento geométrico e uso de modelos log-linear de Poisson. Os ensaios e as ferramentas estatísticas utilizadas permitiram evidenciar que o protocolo necessita de ajustes para melhorar a produção da cultivar Smooth Cayenne que apresentou menor potencial propagativo.

Resumo em Inglês:

ABSTRACT Measuring the propagation potential of any variety, considering micropropagation to obtain the seedlings, has received little attention from researchers. The use of unusual statistical techniques, such as geometric growth rate and exponential regression, can produce important information for planning and applying subcultures based on their in vitro behaviour, which may indicate the need to improve the protocol and to better understand the effects of interval trials and subcultures. The aim of this study was to evaluate the effects of three different subculture intervals on the propagation potential of commercial pineapple cultivars, with the aim of optimising micropropagation protocols and planning for seedling production on a commercial scale. Axillary buds from the Perola, BRS Imperial and Smooth Cayenne cultivars were used for in vitro establishment and multiplication in trials with a subculture interval of 30, 45 and 60 days, in six subcultures. The BRS Imperial cultivar had the best results in the 30-day trial. Although the number of shoots increases as the subcultures progress, the propagation potential is lower. Longer subculture intervals show lower shoot production and propagation potential, as demonstrated by the geometric growth rate and the Poisson log-linear models. The trials and statistical tools employed showed that the protocol needs adjusting to improve production in the Smooth Cayenne cultivar, which had the lowest propagation potential.

Resumo em Português:

RESUMO As influências ambientais e a variabilidade genética podem promover variações entre plantas de uma mesma espécie em características intrínsecas às sementes. Objetivou-se avaliar a divergência entre árvores matrizes de Handroanthus serratifolius a partir de caracteres da qualidade fisiológica de sementes. Sementes colhidas de 13 árvores matrizes foram submetidas aos testes de germinação, condutividade elétrica (CE), de frio, deterioração controlada e envelhecimento acelerado. Foram usadas cinco repetições de 50 sementes para o teste de frio e de 25 sementes para os demais testes. Os dados médios por matriz foram submetidos às análises de agrupamento, pelos métodos de Ward, k-means e Análise de Componentes Principais (ACP). As árvores matrizes foram divididas em 4 grupos pelos métodos de Ward e K-means, e comprovados pela ACP, mas com variações na composição dos grupos entre os métodos. As matrizes do grupo 2 têm qualidade fisiológica inferior, com os menores valores para a maioria dos caracteres avaliados, porém o maior valor de CE e o segundo maior de índice de incerteza da germinação. Por outro lado, o grupo 4 é constituído por matrizes que apresentam sementes de melhor qualidade fisiológica. Oito dos 22 caracteres avaliados são passíveis de descarte, pois contribuem pouco para a variabilidade original dos dados. Os diferentes métodos de agrupamento apontam a existência de divergência entre as árvores matrizes em relação à qualidade fisiológica de sementes, sendo essas informações úteis e que poderão orientar programas de produção de sementes e mudas de H. serratifolius.

Resumo em Inglês:

ABSTRACT Environmental influences and genetic variability can promote, within the same species, variations between plants with intrinsic traits to the seeds. This work aimed at investigating the divergence among Handroanthus serratifolius mother trees from traits related to the physiological quality of seeds. Seeds collected from 13 mother trees were submitted to tests germination, electrical conductivity (EC), cold, controlled deterioration, and accelerated aging. Five replications of 50 and 25 seeds each were used for the cold test and other tests, respectively. The average data per mother tree were submitted to cluster analysis by the methods of Ward, k-means, and Principal Component Analysis (PCA). The mother trees were grouped into 4 clusters by the Ward’s and K-means methods, and confirmed by the PCA, but with varying cluster compositions. Cluster 2 grouped the mother trees with lower seed quality as demonstrated by the lowest values for most of the evaluated traits, but the highest EC and the second-highest value for the germination uncertainty index. On the other hand, cluster 4 grouped the mother trees with better seed quality. Of the 22 evaluated traits, eight are probably suitable for discarding due to their little contribution to the original variability. The results of the different clustering methods indicate significant differences between the mother trees regarding the physiological quality of seeds, showing that these parameters may be used to guide breeding programs aiming to produce high-quality seeds and seedlings of H. serratifolius.

Resumo em Português:

RESUMO O presente trabalho tem como objetivo principal realizar uma pesquisa bibliométrica de literatura sobre o uso de VANTs na cultura de trigo. Para tanto, foi realizada uma pesquisa na base de dados da Web of Science, de todos os artigos científicos publicados até o ano de 2021. Posteriormente foram aplicadas técnicas de análise bibliométrica de literatura através do software VOSviewer, no qual avaliou-se as coautorias entre países e instituições, bem como as coocorrências de palavras entre as obras. Foram verificados os periódicos que mais publicam sobre esta temática e os autores que mais publicam. Os resultados indicam uma tendência crescente de publicações com essa aplicação de VANTs nos últimos 7 anos, e que a China, Estados Unidos da América e Reino Unido são os maiores pesquisadores desse tema, porém a china se destaca com aproximadamente 40% das publicações. Esta análise revela os principais assuntos atuais, e as instituições mais influentes em todo o mundo que realizaram pesquisas relevantes em publicações científicas; este estudo expõe os periódicos que incluem mais publicações e os padrões colaborativos relacionados ao uso de VANTs na cultura do trigo. As plataformas mais utilizadas para essa finalidade são do tipo multirotor, embarcados com câmeras multiespectrais. Cerca de 27,8% das publicações são do eixo temático ligado ao monitoramento da produtividade/fenotipagem. Conclui-se que esta aplicação está em bastante evidência, porém são necessários mais estudos com emprego de drones em regiões com alta produção tritícola como países da América do Sul.

Resumo em Inglês:

ABSTRACT The main objective of this study was to carry out a bibliometric search in the literature on the use of UAVs in the wheat crop. For this purpose, a search of all scientific articles published until 2021 was carried out in the Web of Science database. Subsequently, bibliometric literature analysis techniques were applied using the software VOSviewer, which allowed evaluating the co-authorships between countries and institutions and the co-occurrences of words between studies. The journals and authors that publish the most on this topic were verified. The results indicate a growing trend of publications on UAV applications in the last 7 years, with China, the United States, and the United Kingdom being the main researchers on this topic. However, China stands out with approximately 40% of the publications. This analysis reveals the main current issues and the most influential institutions around the world that have carried out relevant research in scientific publications, showing the journals that include more publications and the collaborative patterns related to the use of UAVs in the wheat crop. Multi-rotor platforms with embedded multispectral cameras are the most used for this purpose. About 27.8% of the publications are from the topic related to the monitoring of productivity/phenotyping. Therefore, this application is in evidence, but further studies on the use of drones in regions with high wheat production, such as South American countries, are needed.

Resumo em Português:

RESUMO As espécies vegetais apresentam diferentes mecanismos de adaptação no que diz respeito à sobrevivência das sementes à dessecação, prevenindo a destruição celular durante a perda de água. O conhecimento desses mecanismos é de grande importância para o entendimento de como ocorre os processos de formação/maturação de sementes e dos processos envolvidos na germinação. Dessa forma, o objetivo deste trabalho foi determinar as alterações fisiológicas e enzimáticas durante o processo de maturação das sementes de melão da cultivar “BRS Anton”, obtidas de frutos em diferentes estádios de maturação e submetidas ao armazenamento pós-colheita, por meio da ação das proteínas totais e das enzimas catalase, peroxidase e superóxido dismutase. Os frutos de melão foram cultivados em casa de vegetação na Embrapa Hortaliças e colhidos em cinco épocas distintas: aos 30, 45, 60, 75 e 90 dias após a antese (DAA). Em cada época, foram colhidos 30 frutos, sendo que 15 frutos tiveram suas sementes extraídas imediatamente após a colheita e 15 frutos foram armazenados por 15 dias. Após o beneficiamento e secagem, as sementes foram submetidas às seguintes análises: germinação, primeira contagem, análise do perfil de proteínas e atividade de enzimas antioxidantes (proteínas totais, peroxidase, catalase e superóxido dismutase). Observou-se que as atividades das enzimas antioxidativas a partir dos 60 DAA sob armazenamento, apresentou um comportamento mais ordenado reafirmando os resultados dos testes fisiológicos. Demostrando que as sementes neste ponto de maturação fisiológica, encontra-se bem formadas e que a secagem não provocou danos em suas membranas celulares.

Resumo em Inglês:

ABSTRACT Plant species have different adaptation mechanisms regarding seed survival to desiccation, preventing cellular destruction during the water loss. The knowledge of these mechanisms is of great importance for the understanding of how the seed formation/maturation processes and the processes involved in germination occur. Thus, this study aimed to determine physiological and enzymatic changes during the maturation process of melon seeds of the cultivar BRS Anton, obtained from fruits at different maturation stages and subjected to post-harvest storage, by the action of total proteins and the enzymes catalase, peroxidase, and superoxide dismutase. Melon fruits were grown in a greenhouse at Embrapa Vegetables and harvested at five different times: 30, 45, 60, 75, and 90 days after anthesis (DAA). Thirty fruits were harvested in each season and 15 fruits had their seeds extracted immediately after harvest and the other 15 fruits were stored for 15 days. After processing and drying, the seeds were submitted to the following analyses: germination, first count, protein profile analysis, and activity of antioxidant enzymes (total proteins, peroxidase, catalase, and superoxide dismutase). The activity of the antioxidant enzymes from 60 DAA under storage showed a more orderly behavior, reaffirming the results of physiological tests. It shows that the seeds at this point of physiological maturation are well-formed and drying caused no damage to their cell membranes.

Resumo em Português:

RESUMO O uso de aeronaves remotamente pilotadas (RPA) tem crescido muito na pulverização agrícola em todo o mundo, no entanto, em virtude de ser algo recente faltam dados de pesquisa que auxiliem os usuários na tomada de decisões assertivas. Este trabalho objetivou avaliar a deposição de calda na cultura do milho (estádio fenológico V5-V6), promovida pela aplicação utilizando uma RPA DJI-AGRAS-MG-1, em duas alturas de voo, em comparação à aplicação com pulverizador costal. O experimento constou de 3 tratamentos e 8 repetições, sendo aplicação com RPA, voando a 1,5 e 3,0 m de altura, e com pulverizador costal. A taxa de aplicação foi de 10 L ha-1 para a RPA e 115 L ha-1 para o costal. Empregaram-se pontas de jato plano em todos os tratamentos. Foram avaliadas deposição de traçador no dossel do milho e perda de calda para o solo, por meio da detecção por espectrofotometria, e cobertura, densidade e espectro de gotas em papel hidrossensível. Também foi avaliada faixa de deposição total e efetiva da RPA. Embora a densidade de gotas proporcionada pela RPA tenha variado entre 26 e 39 gotas cm-2, a cobertura foi inferior a 1,3%. A aplicação a 1,5 m de altura proporcionou deposição de traçador na folhagem semelhante à realizada com o costal. O aumento da altura de voo para 3,0 m reduziu a deposição. A aplicação terrestre promoveu maior perda para o solo. A faixa de deposição efetiva foi de 5,7 e 7,6 m para alturas de voo de 1,5 e 3,0 m.

Resumo em Inglês:

ABSTRACT The use of remotely piloted aircraft (RPA) has grown in agricultural spraying around the world, but there is a lack of research data to assist users in making more assertive decisions due to its recent nature. This study aimed to evaluate spray deposition in corn using an RPA DJI AGRAS-MG-1 at two application heights compared to the application using a knapsack sprayer. Sprayings were carried out in the corn crop at the phenological stage V5-V6. The experiment consisted of three treatments and eight replications, applied with an RPA at heights of 1.5 and 3.0 m and a CO2-pressurized knapsack sprayer. The application rate was 10 L ha-1 for RPA and 115 L ha-1 for the knapsack sprayer. Flat fan spray tips were used for all treatments. Tracer deposition in the corn canopy and spray loss to the soil were evaluated using spectrophotometric detection, while coverage, density, and droplet spectrum were evaluated on water-sensitive paper. Total and effective deposition swath were also evaluated for RPA. Although droplet density provided by RPA varied between 26 and 39 droplets cm-2, the coverage was lower than 1.3%. Application using RPA at the height of 1.5 m provided tracer deposition on corn leaves similar to that carried out with the knapsack sprayer. The increase in application height to 3.0 m promoted a reduction in the deposition. Ground spraying promoted higher spray loss to the soil. The effective deposition swath consisted of 5.7 and 7.6 m for application heights of 1.5 and 3.0 m, respectively.

Resumo em Português:

RESUMO O comportamento altamente recalcitrante das sementes de pupunheira justifica a adequação de um método eficiente para determinação do seu teor de água, uma vez que estas são sensíveis à dessecação. Visto que as sementes de pupunha são consideradas grandes (peso de mil sementes > 200 g) os métodos atuais de determinação do teor de água exigem preparo das sementes, o que é inviabilizado devido a resistência do endocarpo. O objetivo deste trabalho foi comparar diferentes métodos de determinação do teor de água de sementes de pupunheira, visando identificar o mais eficiente para a espécie. Foram testadas diferentes formas de preparo da semente e métodos de secagem. Para todos os tratamentos testados, o início da pesagem ocorreu após a primeira hora, continuando até que a massa de cada repetição se tornasse constante por duas medidas consecutivas. Os dados foram analisados por uma regressão não linear quadrática em platô para avaliar o período de estabilização do teor de água. Assim, o método de estufa a 130 ºC durante quatro horas (com sementes inteiras) é recomendado.

Resumo em Inglês:

ABSTRACT Given the recalcitrant nature of peach palm seeds, which results in high sensitivity to desiccation, more effective approaches to seed quality monitoring are extremely important and justify the need to provide an efficient method to determine their moisture content. For seeds which are considered to be larger (thousand seed weight > 200 g), seed preparation is required, but it is impractical owing to endocarp hardness. The objective of this work was to compare methods of evaluating the moisture content of peach palm seeds, aiming to identify an straightforward method for the species. Different seed preparation and drying methods (oven method at 105 ± 3 °C, low temperature at 103 ± 2 °C, and high temperature at 130 ± 2 °C) were tested. For all methods tested, the beginning of weighing took place after the first hour, and continued until the mass of each repetition became constant for two consecutive measurements. The data were analyzed by nonlinear quadratic plateau regression to evaluate the stabilization period of water content. Thus, the oven method at 130 °C for four hours (with whole seeds) is recommended.

Resumo em Português:

RESUMO O estresse salino destaca-se como um dos principais fatores limitantes na produção agrícola nas regiões áridas e semiáridas, devido os efeitos osmótico e iônico sobre as plantas. Neste contexto, objetivou-se avaliar as respostas fisiológicas de mudas de pinheira irrigadas com águas residuárias salinas sob diferentes doses de NPK. Para isso, o experimento foi conduzido em casa de vegetação, em delineamento de blocos casualizado, em esquema fatorial 3 x 5, com quatro repetições. Foram testadas três águas de irrigação, sendo elas água de abastecimento local (controle), rejeito de dessalinizadores e efluente da piscicultura. E cinco doses de NPK, referentes as proporções de 25, 50, 75, 100 e 125% da recomendação de adubação de 100:300:150 mg dm-3 de N:P:K. As mudas foram conduzidas em recipientes com capacidade de 2 dm3 preenchido com solo de textura arenosa por 90 dias após a semeadura. No final desse período foram avaliadas as trocas gasosas, fluorescência da clorofila e o acúmulo de biomassa. O uso do rejeito salino e efluente da piscicultura na irrigação de mudas de pinha reduziu a atividade fotossintética e o acúmulo de biomassa. As melhores respostas fisiológicas e acúmulo de biomassa ocorrem nas doses de NPK de 75% (75:225:112,5 mg dm-3 de N:P:K) para mudas irrigadas com água de abastecimento, 60% (60:180:90 mg dm-3 de N:P:K) para irrigadas com rejeito salino e 40% (40:120:60 mg dm-3 de NPK), para irrigadas com efluente da piscicultura.

Resumo em Inglês:

ABSTRACT Salt stress stands out as one of the main limiting factors in agricultural production in arid and semi-arid regions, due to its osmotic and ionic effects on plants. In this context, the objective was to evaluate the physiological responses of sugar-apple seedlings irrigated with saline wastewater under different doses of NPK. The experiment was carried out in a greenhouse, in a randomized block design, in a 3 x 5 factorial scheme, with four replicates. Three irrigation waters were tested: local-supply water (control), reject brine and fish farming effluent, and five doses of NPK, referring to the proportions of 25, 50, 75, 100, and 125% of the N:P:K fertilizer recommendation of 100:300:150 mg dm-3. Seedlings were cultivated in 2-dm3 containers filled with sandy soil for 90 days after sowing. At the end of this period, gas exchange, chlorophyll fluorescence, and biomass accumulation were evaluated. The use of reject brine and fish farming effluent to irrigate sugar-apple seedlings reduced photosynthetic activity and biomass accumulation. The best physiological responses and biomass accumulation occur at NPK doses of 75% (75:225:112.5 mg dm-3 of N:P:K) for seedlings irrigated with local-supply water, 60% (60:180: 90 mg dm-3 of N:P:K) for seedlings irrigated with reject brine, and 40% (40:120:60 mg dm-3 of N:P:K) for seedlings irrigated with fish farming effluent.

Resumo em Português:

RESUMO A agricultura conservacionista é fundamental para melhorar a sustentabilidade agrícola. No entanto, a qualidade do manejo do solo em sistemas de agricultura conservacionista é altamente variável. O objetivo deste estudo foi verificar se o índice de qualidade participativa do plantio direto (IQP) está associado aos atributos físicos, químicos e microbiológicos do solo. Dessa forma, buscou-se validar sua utilização como indicador da qualidade do manejo do solo. Foi realizado um levantamento para avaliar as práticas agrícolas utilizadas por agricultores da mesorregião oeste do estado do Paraná, Brasil, para a obtenção do IQP. A qualidade do manejo do solo para as lavouras anuais está relacionada ao IQP, conforme evidenciado por sua associação com atributos físicos, químicos e microbiológicos do solo. Os resultados confirmaram a utilidade da metodologia do IQP como ferramenta de avaliação da qualidade do manejo do solo, demonstrando sua sensibilidade às mudanças de curto prazo nas práticas de manejo. Consequentemente, isso pode permitir o monitoramento da qualidade do manejo e inferências sobre os efeitos benéficos das práticas implementadas.

Resumo em Inglês:

ABSTRACT Conservation agriculture is fundamental for improving agricultural sustainability. However, the quality of soil management in conservation agriculture systems is highly variable. The goal of this study was to verify whether a no-tillage participatory quality index (PQI) is associated with the physical, chemical, and microbiological attributes of soil. Thus, we sought to validate its use as an indicator of soil management quality. A survey was conducted to assess the agricultural practices of farmers from the western mesoregion of the state of Paraná, Brazil to evaluate the PQI. The quality of soil management for annual crops was related to the PQI, as evidenced by its association with soil physical, chemical, and microbiological attributes. These results confirmed the usefulness of the PQI methodology as a tool for assessing the quality of soil management, demonstrating its sensitivity to short-term changes in management practices. Consequently, this may allow for the monitoring of management quality and inferences about the beneficial effects of the implemented practices.

Resumo em Português:

RESUMO A abelha Epanthidium tigrinum é nativa do Brasil e apresenta potencial para uso na polinização de culturas agrícolas. No entanto, a pouca informação disponível sobre seus hábitos reprodutivos e alimentares tem impedido qualquer criação ou manejo racional dessas abelhas. O objetivo deste estudo foi investigar a sua aceitação de ninhos-armadilha, e o seu comportamento de nidificação e forrageamento, com vista a compreender o potencial da espécie para a criação racional. Ninhos-armadilha foram oferecidos, e as fêmeas foram observadas por 16 meses para monitorar o estabelecimento, construção e fechamento dos ninhos, bem como suas arquiteturas e o comportamento das abelhas na busca dos recursos utilizados para a construção e provisão dos seus ninhos. Os resultados mostraram que E. tigrinum tem um bom desempenho em ninhos-armadilha; prefere cavidades com diâmetro em torno de 0,45 cm; depende de outros recursos vegetais além do pólen e do néctar, como folhas, fibras e resinas, para construir seu ninho; e permanece ativa durante todo o ano. O estudo concluiu que a espécie tem potencial para uso em programas de polinização agrícola; no entanto, as exigências de nidificação observadas devem ser levadas em consideração, tanto nos esforços de conservação quanto na exploração zootécnica quando criando a abelha para polinização agrícola, pois ambas as situações podem influenciar o número de ninhos e células construídas e, consequentemente, o tamanho da população de polinizadores.

Resumo em Inglês:

ABSTRACT The bee Epanthidium tigrinum is native to Brazil and shows potential for use in pollinating agricultural crops. However, the little information available concerning its reproductive and feeding habits has prevented any rational breeding or management of these bees. The aim of this study was to investigate their acceptance of trap nests, and their nesting and foraging behaviour, with a view to understanding the potential of the species for rational breeding. Trap nests were offered, and the females were observed for 16 months to monitor the establishment, building and closing of nests, as well as their architecture and the behaviour of the bees when searching for the resources used to build and provision the nests. The results showed that E. tigrinum performs well in trap nests; prefers cavities with a diameter of around 0.45 cm; depends on other plant resources besides pollen and nectar, such as leaves, fibres and resins, to build its nest; and remains active throughout the year. The study concluded that the species has the potential for use in agricultural pollination programs; however the observed nesting requirements must be taken into account, both in conservation efforts and in zootechnical exploitation when breeding the bee for agricultural pollination, as both can influence the number of constructed nests and cells, and consequently, the size of the pollinator population.

Resumo em Português:

RESUMO Na experimentação agrícola, a utilização do tamanho ótimo de parcela é uma estratégia importante, para aumentar a precisão experimental, e trabalhos desta natureza são escassos para a cultura do grão-de-bico, leguminosa que vem conquistando o mercado e consumidores em todo o mundo. Assim, o objetivo deste trabalho foi determinar o tamanho ótimo de parcela, para avaliar experimentos com a cultura do grão-de-bico, em cenários formados por combinações de números de tratamentos, números de repetições e níveis de precisão. Dois experimentos em branco foram realizados, compostos por oito linhas de cultivo, de 7 m de comprimento, espaçadas em 50 cm entre linhas e 10 cm entre plantas; foram avaliadas as seis linhas centrais, totalizando 60 plantas por linha de cultivo. Foi determinado o índice de heterogeneidade do solo e o tamanho ótimo de parcela foi estimado por meio do método de Hatheway, em cenários formados pelas combinações de i tratamentos (i = 4, 8, 12 e 16), r repetições (r = 3, 4, 5, 6, 7 e 8) e níveis de precisão (DMS = 25%, 30% e 40%). O índice de heterogeneidade do solo foi superior a 0,7 para todas as variáveis avaliadas. O método de Hatheway possibilita estimar diferentes tamanhos de parcelas, de acordo com as condições e limitações da área experimental. Em experimentos com o grão-de-bico, com 4 a 16 tratamentos, DMS de 25% e seis repetições, as parcelas de 25 unidades básicas são suficientes para identificar, com probabilidade de 5%, diferenças significativas entre as médias dos tratamentos.

Resumo em Inglês:

ABSTRACT In agricultural experimentation, use of the optimum plot size is an important way of increasing experimental precision; however, studies of this type are scarce for the chickpea, a legume that has been conquering both the market and consumers throughout the world. The aim of this study, therefore, was to determine the optimum plot size for evaluating experiments with the chickpea, in scenarios comprising combinations of the number of treatments, number of replications and levels of precision. Two blank experiments were carried out, comprising eight crop rows, 7 m in length, at a spacing of 50 cm between rows and 10 cm between plants; the six central rows were evaluated, giving a total of 60 plants per row. The index of soil heterogeneity was determined, and the optimum plot size was estimated using the Hatheway method in scenarios formed by a combination of i treatments (i = 4, 8, 12 and 16), r replications (r = 3, 4, 5, 6, 7 and 8) and levels of precision (LSD = 25%, 30% and 40%). The index of soil heterogeneity was greater than 0.7 for each of the variables under evaluation. The Hatheway method makes it possible to estimate different plot sizes based on the conditions and limitations of the experimental area. In experiments with the chickpea including 4 to 16 treatments, 25% LSD and six replications, plots of 25 basic units are sufficient to identify significant differences between the mean values of the treatments with a probability of 5%.

Resumo em Inglês:

ABSTRACT Irregular rainfall and the occurrence of droughts in tropical semi-arid regions have a negative impact on the quality and availability of water stored in reservoirs. The aim of this study was to evaluate the quality of water stored in an artificial reservoir in the tropical semi-arid region of Brazil during years of drought. The study area was the Pereira de Miranda reservoir, located in the district of Pentecoste, Ceará, Brazil. Seven water-sampling campaigns were carried out between April 2015 and September 2016. The variables to be analysed were chlorophyll-a (Cl-a), hydrogen potential (pH), electrical conductivity (EC), total nitrogen (Ntotal), total phosphorus (Ptotal), transparency (SD), fixed/volatile/total suspended solids (FSS/VSS/TSS), and temperature (T0); the trophic state index (TSI) was then calculated. The variables which better explained the variance in water quality were identified by principal component analysis (PCA). The waters of the Pereira de Miranda reservoir were classified as hyper-eutrophic throughout the study period and at each of the collection points. The PCA identified that the variability in water quality was determined by suspended sediment and nutrients, showing that the reduction in variables made it possible to obtain high explainability of the conditions of the reservoir during monitoring, saving time and resources on the analyses. In addition, the occurrence of severe drought resulted in low accumulated volumes, which intensified and made vulnerable the quality of the waters. As such, the Pereira de Miranda reservoir proved to be in a process of degradation, mainly due to anthropogenic action, intensified by climate factors.

Resumo em Inglês:

ABSTRACT Knowledge of soil water dynamics is essential for establishing appropriate methods of irrigation management. Water dynamics in unsaturated soils is a complex process that can be explained by the Richards equation. As this is a non-linear differential equation, there is no analytical solution, but requires the use of the finite element method, for example, to obtain solutions, where simulations using numerical modelling make it possible to predict the the flow of water from the soil. As such, the aim of this study was to evaluate a 2D numerical model in simulating water distribution and wet bulb formation resulting from a subsurface irrigation system, in addition to validating the generated model. The Pearson correlation coefficient (r), the coefficient of determination (R2) and the root-mean-square error (RMSE) were calculated. For each treatment, both during and after irrigation, the model showed a small relative error, high values for R2 and a positive correlation with the field data. It was concluded that the model is applicable to the design and management of subsurface irrigation systems, varying the installation depth of the drip tube, the spacing between emitters and the soil moisture, giving good results for the various simulated scenarios.

Resumo em Inglês:

ABSTRACT Forage cactus species are cultivated in northeaster Brazil for feed, mainly during dry periods, as cacti are xerophytes well adapted to drought. Gas exchange studies have elucidated the physiological mechanisms underlying plant adaptation to ecosystems with low water availability. Here, we evaluated the variability between and within cactus forage genera Opuntia and Nopalea with respect to gas exchange behaviour. Twenty-one cultivars were used, 16 of which belonged to genus Opuntia, while six belonged to genus Nopalea, particularly, O. cochenillifera. Gas exchange was evaluated in the secondary cladode at 00:00 hours using a portable infrared gas analyser. Net CO2 assimilation rate, stomatal conductance, CO2 intercellular concentration, transpiration rate, and leaf temperature were evaluated. Additionally, instantaneous water use efficiency, intrinsic water use efficiency, and instantaneous carboxylation efficiency were calculated. Boxplots were used to assess value dispersion between the genera prior to submitting the data to multivariate analysis of principal components and cultivar-based grouping, and subsequently organizing the species studied in a dendrogram. Variability between the two genera and among cactus forage cultivars was detected for gas exchange. Cultivars were classified into three groups and two main components were identified. Cultivars 'Verdura' and 'Orelha de Elefante Mexicana’ showed higher photosynthetic performance.

Resumo em Inglês:

ABSTRACT Among the main problems that compromise the development of forest species are water and salt stresses, especially in the early stages of development, when seedlings are more sensitive. Thus, the objective of this study was to evaluate the morphophysiological and biochemical changes in Enterolobium contortisiliquum seedlings subjected to abiotic stresses. The experimental design was randomized complete blocks (RCB), composed of five treatments, with four replicates, and the experimental plot consisted of twenty plants. From the 31st day after sowing, when the seedlings reached approximately 15 cm in height, they began to receive the treatments, which consisted of different levels of electrical conductivity of irrigation water (0.3; 2; 4; 6; 8 dS m-1) for salt stress and periods of water restriction (0; 4; 8; 12 and 16 days without irrigation) for water stress. The traits evaluated were: plant height, root length, stem diameter, number of leaves, leaf area, total dry matter, Dickson quality index, height/shoot dry matter ratio, total soluble sugars, starch, total amino acids and proline. An increase in the electrical conductivity of irrigation water and days without irrigation compromised the development of E. contortisiliquum seedlings, which was intensified from 2 dS m-1 and four days without irrigation for salt and water stresses, respectively. The mechanism of survival of E. contortisiliquum to abiotic stresses involves reduction in the growth and quality of seedlings, with activation of biochemical defense mechanisms of the species.

Resumo em Inglês:

ABSTRACT This work aims at evaluating and discriminating crambe genotypes regarding tolerance to water deficit by means of morpho-agronomic and physiological traits. The trial was carried out in a greenhouse under a randomized complete block design with four blocks, in a 2 x 8 factorial scheme, being two environments (with and without stress) and eight genotypes (FMS CR 1101, FMS CR 1106, FMS CR 1203, FMS CR 1305, FMS CR 1307, FMS CR 1312 and FMS CR 1326 and cultivar FMS Brilhante). The genotypes were evaluated according to physiological and morpho-agronomic traits. The significance of the mean squares was tested by the F test (P < 0.05) and the genetic parameters were estimated as ratio b between the genetic (CVg) and experimental (CVe) coefficients of variation, broad-sense heritability at genotypic mean level (h^m2), intraclass correlation (r) and selective accuracy (Ac). In general, water deficit did not cause severe physiological limitations to the plants. Plant height (PH), total dry mass (TDM) and grain yield (GY) were the traits that stood out for presenting the highest estimates of ratio b, h^m2), CVg and r, revealing the possibility of genetic gains with the selection. Nevertheless, after evaluating the performance of genotypes in terms of physiological and morpho-agronomic traits, it was concluded that cultivar FMS Brilhante and inbred lines FMS CR 1326 and FMS CR 1106 had the most favorable traits for the selection, therefore, presenting potential for water deficit tolerance.

Resumo em Inglês:

ABSTRACT Global consumption of oilseeds has been growing progressively in the last five growing seasons, in which soybean represents 60% of this sector. Thus, in order to maintain a high production in the region of Rio Verde, State of Goiás, against the phytopathological problems, this study aimed to define the best spectral range for the detection of H. glycines and P. brachyurus by linear regressions in soybean at R3 stage, as well as the elaboration of mathematical models through multiple linear regressions. For this, soil and root were sampled in the experimental area, as well as a flight was performed with the Sentera sensor. Data were used for the elaboration of regressions and for the validation of 2 mathematical models. Significant values were observed in simple linear regression only for cysts, in the visible range, with a good R² value for the Green, Red and 568 nm bands, to nonviable cysts. When working with the stepwise statistics, better results are found for H. glycines, which now has an R²(aj) of 0.7430 and P. brachyurus is then detected. From the mathematical model obtained with the multiple linear regression for non-viable cysts with an R²(aj) of 0.7430, it is possible to detect the spatial distribution of nematodes across the soybean field, in order to perform a localized management, optimizing the applications. Good results are also possible using the mathematical model obtained by simple linear regression.

Resumo em Inglês:

ABSTRACT The floodplain forests of the Amazon estuary have undergone constant change over recent years, where management techniques, especially intensive management, have had an impact on the dynamics of the vegetation and land use. These changes can be monitored using satellite data. With this in mind, the aim of this study was to evaluate the dynamics of ground vegetation on the islands of Jarimbu, Mamangal, Itaboca, Mutirão and Buçu in the district of Igarapé-Miri, Pará, using images from the RapidEye and Planet satellites. The unsupervised ISODATA classification method was used, generating distinct classes of vegetation between each island. To evaluate the efficiency of the classification, an average of 200 random points were used, with another 30 points relating to the type of usage for each class. The Kappa index and overall precision were also analysed, in addition to calculating errors of omission and commission. Monitoring on a seven-year time scale using high-resolution satellites, a more than 50% increase in the Exposed Soil class was seen for the islands of Jarimbu, Mutirão and Itaboca, the latter responsible for an increase of more than 50% in the Urban Area class. On each of the five islands, the Alluvial class, representing the areas of açaí groves, has emerged over the last seven years, increasing in area at the expense of a reduction in the Arboreal class. In this respect, the confusion matrix showed a mean accuracy for the islands of ‘very good’, with a mean overall precision of 77.74%, and a mean Kappa index of 0.73, indicating strong agreement with the reference data and the classification.

Resumo em Inglês:

ABSTRACT In family farming, mechanisation, when appropriate to the task and to the size of the property, can be one way of easing tiring and repetitive work, such as garlic harvesting. The present study is based on a model of harvester currently on the market, and proposes several improvements for mechanising the harvest on family farms, with an emphasis on sloping terrain, to reduce costs and increase productivity. Since the equipment currently on the market reduces the operational performance of these producers resulting in the high prices of commercial garlic, the aim of this study was to evaluate, using the Finite Element Method, the von Mises stresses and the displacement of a garlic harvester in different topographies. A structural analysis was carried out, and the vibration modules in the three main parts that make up the structure of the garlic harvester were checked: the structure supporting the scarifier point, the structure of the plant transport system, and the structure at the rear of the harvester. The structural modifications that were implemented corrected the initial high-stress conditions, showing improvements in stress concentration and areas of displacement. As such, the entire structure of the garlic harvester tends to withstand the proposed loads. From the results of the simulations, we conclude that the connecting support may undergo greater response from structural dynamics, and that frequencies greater than 45.7 Hz should be avoided since there are several natural frequencies above this range that might cause interference to the structure.

Resumo em Inglês:

ABSTRACT The long-term use of agrichemicals might add some heavy metals to soils and, there is little information about the dynamics of these elements in soils under saline conditions in semiarid regions. This study aimed to investigate the dynamics of heavy metals in the different fractions of Fluvic Entisols with saline conditions under long term of coconut cultivation in a semiarid region. Composite soil samples were collected in five agricultural areas and three areas under native vegetation. Physical, chemical, and heavy metal analyses were carried out in soil (semi total and fractionated contents). Quality of irrigation water and drainage water was also evaluated. Analytical results were normalized and subjected to analysis of variance, and means were compared by Scott-Knott test (P < 0.05). Pearson correlation analysis was also used to assure a minimum correlation of variables justifying its use in the matrix of a factorial analysis. Semi-total contents of Cr, Ni, Pb and Zn (except Cu in some areas) were lower than previous local assessment and national guiding values, indicating that they do not cause harmful alterations in soil quality. Analyses of waters showed high levels of HCO3, indicating moderate restriction to use (due to the high levels of EC, SAR, Na and Cl). Fractionation of heavy metals revealed low risk of environmental pollution since most metal contents were bound to the oxidic, organic and residual fractions. The water used in irrigation contributes to the contents of heavy metals and to the salinity condition of the evaluated soils.

Resumo em Inglês:

ABSTRACT The determination of the number of experiments required to achieve high coincidence in identifying significant correlations between culinary quality traits and/or mineral concentrations is unprecedented for common bean. The objectives of this study were to evaluate correlations between culinary quality traits and minerals in common bean lines considering data from individual and combined experiments; define the minimum number of experiments that provide high coincidence in identifying significant correlations; and identify promising traits for indirect selection. For this, seven traits related to culinary quality and the concentration of six minerals in grains of 17 common bean genotypes were evaluated. Pearson’s linear correlation analysis was performed on data obtained from four individual experiments and six combinations of experiments. Twelve of the 13 evaluated traits showed a significant genotype × environment interaction effect, indicating that the common bean genotypes exhibited differences in culinary quality and mineral concentration when these were determined in different experiments. Pearson’s linear correlation coefficients vary in significance, sign, and/or magnitude for the traits analyzed in individual and combined experiments. The use of data from three experiments provides a high coincidence percentage in identifying significant correlations in Pearson’s linear correlation analysis. Common bean lines with high culinary quality and greater mineral concentration can be indirectly selected based on higher L* values (grain lightness) and higher calcium concentrations.

Resumo em Inglês:

ABSTRACT Given the heterogeneity of soils in Roraima state, Brazil, and the need for a phosphorus (P) extraction protocol, this study aimed to assess the efficiency of the Mehlich-1, Mehlich-3, Bray-1 extractants and anion exchange resin (AER) in determining available P in soils representative of the state. The chemical, physical and mineralogical attributes of seven soil classes were determined. The experiment was conducted in a greenhouse, using a randomized block design in a 7 x 5 factorial scheme with four repetitions. The first factor was the soils (LA (ITÃ), LV (ITÃ), LA (SERRA DA PRATA), LA (CCA), PA (CCA), FT (BONFIM), SN (SURUMU)), and the second P doses, estimated based on the maximum P-adsorption capacity (MPAC). A polyethylene pot containing 5 dm3 of soil and five plants was defined as the experimental unit. The indicator species was corn grown in two 30-day phases. The P doses were applied using monopotassium phosphate. Soil samples were removed before planting to determine available P using the extractants. Corn dry weight was assessed at the end of the two-phase experiment. Correlation tests were performed for dry weight versus extractant and extractant versus extractant. The Mehlich-3 and Bray-1 extractants were the most sensitive to variations in soil attributes. The resin exhibited the greatest correlations with the different soils individually and combined, showing potential in determining available P in soils from the humid tropical region of the Brazilian Amazon.

Resumo em Inglês:

ABSTRACT Peanut cultivation in the northeast of Brazil has been badly affected by salts accumulating in the irrigation water; in this respect, the use of plant mulch is one way of mitigating salt stress. The aim of this study was to evaluate the effect of irrigation using brackish water under different mulching strategies on productivity and water use efficiency in the peanut. The experiment was carried out under field conditions in Redenção, in the state of Ceará, in a randomised block design of split-plots with five replications, in which the plots corresponded to two levels of electrical conductivity of the irrigation water (0.8 and 4.0 dS m-1), and the subplots to six mulching strategies based on the phenology of the crop (MS1: mulch throughout the cycle; MS2: flowering stage; MS3: appearance of the gynophore; MS4: pod formation; MS5: final flowering stage; MS6: no mulch). The following were determined at the end of the experimental cycle: commercial, non-commercial and total number of pods, number of grains per pod, pod length and diameter, productivity and water use efficiency. Irrigation with lower-salinity water, together with mulching during the phenological stages of the peanut, affords better productive performance and greater water use efficiency. Salt stress reduced the length and diameter of the pods and had a negative effect on productivity and water use efficiency, both with and without the use of plant mulch during the phenological stages.

Resumo em Inglês:

ABSTRACT Genipa americana L. is a forest species of high socioeconomic potential. However, predatory extractivism actions threaten its existence, making it necessary to adopt conservationist practices. G. americana seeds show sensitivity to desiccation and cooling, making it unfeasible for conservation by conventional methods. Thus, cryopreservation is an promising alternative for the long-term conservation of species that produce unorthodox seeds, such as the genipap. In this sense, the objective was to cryopreservation of seeds of G. americana and to evaluate the effects of desiccation and freezing on germination and establishment of seedlings. Initially, seeds were dehydrated in silica gel 0, 16, 18, 20, 22 and 24 h, and then were cryopreserved in liquid nitrogen (LN) (-196 °C) during 24 h. After thawing, the viability and germination were analyzed. Dehydrated and non-cryopreserved seeds were also analyzed. The silica gel desiccation caused a reduction in viability and germination of the seeds of G. americana. The initial seed water content was so high (47%) that storage in LN (+LN) without prior dehydration treatment resulted in seed mortality. It was verified that, the dehydration in silica gel for the minimum time 20 h (corresponding to 14% water content) provides greater freezing tolerance, allowing the successful cryopreservation. Silica gel dehydration followed by immersion in LN was shown to be highly efficient for cryopreservation of seeds of G. americana, besides germinatio after thawing, high survival rates (100%) were obtained, with growth and normal establishment of the seedlings after acclimatization.

Resumo em Inglês:

ABSTRACT Multicollinearity must be diagnosed in multivariate analyses. Among the indicators, the condition number can be used to quantify the degree of multicollinearity. Hence, this study sought to determine the number of measurements (trials) necessary to estimate the number of condition in linear correlation matrices between rye traits. Five uniformity trials were carried out with ‘BRS Progresso’ rye, and eight morphological traits and eight productive traits were evaluated, forming two groups. In each group of traits, six cases (combinations of traits) were planned and the multicollinearity diagnosis was performed. Repeatability analyses were performed using the following methods: analysis of variance, principal component analysis, and structural analysis, and the number of measurements (trials) was determined for different levels of precision. A higher condition number of repeatability coefficients was obtained by the principal component methods (based on correlation and variance and covariance matrices) and structural analysis based on the variance and covariance matrix. A greater number of measurements (trials) is necessary to estimate the number of conditions in productive traits compared to morphological ones. One trial is enough to efficiently estimate the condition number with a minimum accuracy of 80% in morphological and productive traits of rye, whereas at least three trials are required for 95% accuracy.

Resumo em Inglês:

ABSTRACT The Brazilian bocachico is a rheophilic fish from the northeast region of Brazil that holds great economic and scientific interest. The absence of evident sexual dimorphism and the invasive character of sexing methods and evaluation of gonadal maturation are obstacles to its artificial reproduction. In this scenario, ultrasonography emerges as a non-invasive method for sexing. The objectives of this study were to establish an ultrasound sexing method for Brazilian bocachico and select equations to estimate the gonadosomatic index (GSI), gonad weight (GW), and gonad volume (GV) of live bocachico. A total of 32 bocachico fish (18 females and 14 males) were analyzed ultrasonographically and morphologically. The association of morphometric and ultrasonographic parameters was investigated using Pearson Correlations. The following prediction equations were selected using multiple regression analysis: GSI = 16.22 × transvarea; GW = 30.3 × transvarea; and GV = 0.001260036 × pixels. A model capable of predicting the sex of the animals based on the ultrasonographic parameters was obtained using partial least-squares discriminant analysis with principal component analysis. The significance level adopted was P < 0.05. In conclusion, ultrasonography is a useful tool to perform sexing and evaluate the gonads during the breeding season, contributing to artificial reproduction in captivity.

Resumo em Inglês:

ABSTRACT Reference evapotranspiration (ET0) and rainfall are basic variables for estimating the net irrigation depth (NID). The objective of this study was to estimate the NID for designing irrigation systems in Piracicaba, SP, Brazil, using ET0 and rainfall probability distributions. A 30-year ET0 and rainfall dataset (1990-2019) was obtained from the ESALQ/USP weather station. The water balance between ET0 and rainfall indicated July, August, and September as months of higher water deficit. Based on the first-order Markov chain, August presented the highest water deficit. Rainfall and ET0 were estimated on 19 probability levels, and four probability distributions such as normal, log-normal, beta, and mixed gamma were evaluated. The analysis of historical August series using accumulated values in periods of five, ten, or 15 days is recommended for sizing irrigation designs in Piracicaba, SP, Brazil. The log-normal and mixed gamma probability distributions presented the best fit for ET0 and rainfall data, respectively. To reach a crop coefficient Kc = 1 in Piracicaba, SP, Brazil in August, the irrigation system should be designed for an NID of 4.1 mm day-1. The use of mean monthly rainfall and ET0 values for designing irrigation systems underestimates the NID by a mean of 26.6% compared to estimates made at a probability of 75% at five-, ten-, and 15-day intervals because the mean rainfall values occurred with exceedance probabilities of < 36%, and mean ET0 values occurred with non-exceedance probabilities of < 56%.

Resumo em Inglês:

ABSTRACT The effects of machinery traffic and cover crops on soil physical properties have been underexplored under no-till agricultural production in subtropical environments. The objective of this study was to quantify the soil water infiltration rate and related soil physical properties in response to tractor traffic levels (0, 2, 5, and 20 passes) and the presence or absence of cover crops in a Xanthic Hapludox soil over two growing seasons under no-till conditions. The experiment was carried out in a randomized block design arranged in a factorial scheme with four replications. The traffic factor was constituted by the number of passes with a 6 Mg weight tractor. The winter crop management practices factor consisted of the cover crops (i) black oat (Avena strigosa) in 2017 and turnip (Raphanus sativus var. oleiferus) in 2018 compared with (ii) fallow with spontaneous vegetation. The soil water infiltration rate increased with cover crops when compared to fallow. Regarding tractor traffic levels, shortly after soil compaction, there was a lower water infiltration rate at 20 passes, 45 mm h-1 lower than the absence of tractor traffic. The soil water infiltration rate was positively correlated with macroporosity and negatively correlated with soil bulk density. After 14 months of soil compaction caused by tractor traffic, an improvement in the soil physical properties and the water infiltration rate was found, which were enhanced by the inclusion of cover crops.

Resumo em Inglês:

ABSTRACT Nutri-priming is a low-cost and highly effective way of supplying seeds with micronutrients. The aim of this study was to evaluate the physiological quality of seeds of the Pérola cultivar of the common bean under nutrient solutions containing molybdenum, cobalt and zinc for different imbibition times. The experiment was carried out in the laboratory and greenhouse of the State University of Goiás UEG - UnU Ipameri, using a completely randomised experimental design, with eight micronutrient treatments (T1. Control; T2. Mo; T3. Zn; T4. Co; T5. Mo + Co; T6. Mo + Zn; T7. Zn + Co; T8. Mo + Co + Zn) and six imbibition times (6, 8, 12, 16, 20 and 24 hours). The variables under analysis were seed imbibition, germination test, first germination count, accelerated ageing, seedling emergence, emergence speed index, shoot length, root length, total length, fresh weight, dry weight, and shoot and root biomass. The micronutrients afforded an increase in germination in the seed batches under evaluation; on the other hand, imbibition times of greater than four hours reduced the germination capacity of the seeds. It can be concluded that nutri-priming in the common bean is only beneficial for an imbibition time of up to four hours.

Resumo em Inglês:

ABSTRACT The objective was to verify if the primary root emission can be recommended as a vigor test for soybean seeds. For this, five lots of varieties ANTA 82, NA7337 and BRS1074IPRO were evaluated by first count, germination, emergence, emergence speed index and tetrazolium tests. In the root protrusion test at 20, 25 and 30 ºC, two evaluation criteria were adopted: primary root emission precocity index (PREPI) and percentage of seeds that emitted the primary root (PRE). The seeds counted were those with a primary root equal to or greater than 2 mm, every 12 h from the installation of the test until 120 h. The design was completely randomized and means were compared, within each evaluation time, using the Scott-Knott test at 5% probability. Pearson’s linear correlation was performed for PREPI and PRE with emergence. PREPI was not considered efficient. For the PRE, at 20 ºC, there was a correlation at 72 h, for the three varieties. At 25 ºC there was a correlation for a period of 36 h for ANTA 82 and NA7337 and 60 h for BRS1074IPRO. At 30 ºC there was a correlation in the time of 36 h for the three cultivars. Considering that speed in obtaining results is important in vigor tests, it is concluded that primary root emission for 36 h after installing the test at 30 ºC is recommended as a vigor test in the quality control of soybean seeds.

Resumo em Inglês:

ABSTRACT Melon cultivation under saline conditions is a challenge, as the plants can suffer a reduction in fruit production and quality. The aim of this study was to evaluate the production and quality of noble melon fruit fertigated with different saline solutions and K/Ca ratios. The experimental design was of randomised blocks, with treatments arranged in a 3 x 6 factorial scheme, using three melon cultivars (Bazuca, McLaren, County) fertigated with six nutrient solutions [S1 - standard nutrient solution (SNS); S2 - SNS + NaCl (5.0 dS m-1); S3 - S2 enriched with K (50%); S4 - S2 enriched with K (100%); S5 - S2 enriched with Ca (50%); S6 - S2 enriched with Ca (100%)]. At the end of each cultivar cycle, the fruit was harvested and assessed for the following parameters: fresh fruit weight, fruit diameter, internal cavity, pulp thickness, pulp firmness, soluble solids content, titratable acidity, soluble solids/titratable acidity ratio, and vitamin C. Salt stress impaired the physical characteristics of the fruit of the three noble melon cultivars. The nutrient solution enriched with 50% K (S3) did not reduce the effect of salt stress on fresh weight or fruit size in the melon, but afforded an increase in fruit quality.

Resumo em Inglês:

ABSTRACT Sweet sorghum has been shown to be an alternative for ethanol production in several regions. Because it is sexually propagated, the use of quality seeds becomes an important factor for obtaining an adequate plant stand and, consequently, good productivity. Thus, the objective was to evaluate the production and physiological maturation of seeds of sweet sorghum cv. BRS 511, in response to the interval between irrigations during the reproductive period and harvesting period. Two experiments were carried out in a greenhouse, the experimental design adopted was in randomized blocks, with four replications in a 3 x 2 split-plot scheme, corresponding to three intervals between irrigations during the reproductive stage (0; 4 and 8 days) and two harvest times (102 and 110 days after sowing). The following parameters were evaluated from the harvested panicles: number of seeds, weight of one thousand seeds, water content, germination, first germination count, emergence in sand and emergence speed, electrical conductivity and seedling vigor. The production of seeds per panicle and the weight of a thousand seeds were significantly influenced by the increase in the interval between irrigations in the 2nd experiment, with a reduction of 50.4 and 46.3%, respectively. Water replacement every eight days caused a reduction of up to 43.4% in the first germination count and 16.3% in germination. The production and quality of sweet sorghum seeds reduces as a function of the increase in the interval between irrigations and the harvesting time, presenting germination rates below the required for commercialization.

Resumo em Inglês:

ABSTRACT Water erosion is a natural geological process that is common in tropical regions. It is important to monitor it to contain its physical, environmental, and socio-economic impacts. In the Espírito Santo state, Brazil, much of the land is used for agriculture and studies related to water erosion are scarce. The spatial modeling of water erosion is useful for proposing mitigating measures because combining it with data from geographic information systems can identify the areas most prone to soil loss. The Revised Universal Soil Loss Equation - RUSLE, is a model that requires little input data and is easy to use, providing results useful of helping to mitigate water erosion and promote sustainable land use planning. This study estimates the water erosion rates in the Espírito Santo state by RUSLE and compares them with the soil loss tolerance (T) limits. The parameters used in the model are the land use and management, the soil attributes, the relief and the climate factors. Approximately 38.65% of the state’s area shows soil loss above the T limit (7.79 - 14.14 Mg ha-1 year-1). The areas with steeper slopes and low vegetation cover have most of the highest erosion rates. The mean annual soil loss of the entire state is 33.55 Mg ha-1 year-1. RUSLE provided a diagnosis useful of directing erosion mitigation measures to the most susceptible areas, enabling sustainable planning to support the state's socio-economic development.

Resumo em Inglês:

ABSTRACT Information on irrigation management is essential for achieving satisfactory results when cultivating the green pepper. The aim of this study, therefore, was to evaluate the effects of water deficit, which varies according to phenological stage, on the production, growth and physiology of a crop of green peppers. The experimental design was completely randomised, with seven treatments, four repetitions, and plots comprising two plants. The treatments consisted of replacing the water demand during phenological phases I, II, III and IV (in terms of percentage ETc): T1 - 100%/I, 100%/II, 100%/III and 100%/IV; T2 - 100%/I, 75%/II, 100%/III and 75%/IV; T3 - 100%/I, 75%/II, 75%/III and 75%/IV; T4 - 100%/I, 75%/II, 75%/III and 50%/IV; T5 - 100%/I, 50%/II, 75%/III and 50%/IV; T6 - 100%/I, 50%/II, 50%/III and 50%/IV; T7 - 100%/I, 50%/II, 50%/III and 25%/IV. The plants were grown in the field under drip irrigation. The following variables were analysed: plant height; stem diameter, leaf area, shoot dry weight, number of fruits per plant, soluble solids, fruit length, fruit diameter, fruit weight, productivity, relative chlorophyll index, gas exchange, and water use efficiency. Compared to T1, management based on T2, T3 and T4 did not reduce expression of the vast majority of the vegetative variables or of gas exchange. The water deficit from T2 can be employed without any significant reduction in productivity and affords water savings of 12.5% in relation to T1. T1 and T2 give the highest values for water use efficiency. Management based on T1 and T2 is therefore recommended for cultivating the green pepper under field conditions.

Resumo em Inglês:

ABSTRACT The aim of this study was to analyse patterns of spatial dispersal in Ceratitis capitata using two types of attractive traps and propose a predictive model of pest dispersal with the aim of determining management zones for decision-making. The experiment was conducted in an orchard of the ‘Palmer’ mango in the district of Belo Campo, Bahia. Sampling was carried out using McPhail and Jackson traps. The pattern of spatial dispersal in C. capitata was determined using the Perry and Mead Index of Dispersion, the Morisita Index, and the Local Moran index (LISA). The spatial variability of the abundance of C. capitata was obtained by geostatistical analysis, with the indicator kriging method used to prepare the location and spatial distribution maps. The Perry and Mead Index of Dispersion and the Morisita Index showed an aggregated pattern of spatial dispersal, whereas the Moran Local index showed a random pattern from 7 DFSH (days from the start of the harvest) to 35 DFSH, and an aggregated pattern at 42 DFSH. The SDI was strong at 7 and 35 DFSH and moderate at 14, 28 and 42 DFSH. The dispersal patterns of C. capitata allow an exponential predictive model to be produced, outlining strategies for exponential management zones of C. capitata, and detecting which places have the highest risk of the pest occurring.

Resumo em Inglês:

ABSTRACT Water reservoirs were built in the semi-arid region to mitigate the effects of drought and water scarcity. However, these reservoirs are subject to variables that impact the volume and quality of the stored water, with the contribution of such nutrients as Total Nitrogen (TN) and Total Phosphorus (TP) being one of the main factors in intensifying the eutrophication process. The aim of this study was to quantify the principal inputs and outputs of nutrients (N and P) and calculate the nutrient balance, in order to verify the influence of seasonality on the import and export of these nutrients in surface reservoirs of the semi-arid region of Brazil. Seven campaigns were carried out between 2015 and 2016, with water samples collected at five points in the Pereira de Miranda reservoir and four in the General Sampaio reservoir. The inflow of nutrients was greater when the inflow rate of the water was higher. The balance showed the accumulation of 22.8 tons of TN and 2.8 tons of TP in the Pereira de Miranda reservoir, and 13 tons of TN and 1.5 tons of TP in the General Sampaio. These reservoirs are therefore retaining nutrients, acting as a storage site for nutrients transported by surface runoff in the basin of the Curu River. This increase in storage occurred mainly during the rainy season, when nutrient retention by the reservoirs impaired water quality, resulting in eutrophication, and making it difficult to meet the uses for which the reservoirs were intended.

Resumo em Inglês:

ABSTRACT Vast areas of the Brazilian Amazon have been deforested for the expansion of livestock and the agricultural frontier, which has resulted in soil exhaustion. It is therefore urgent to reduce deforestation and encourage sustainable land use to promote social and economic development in the region. The aim of this study was to evaluate the impact of different land use systems (an agroforestry system, cassava cultivation, non-degraded pasture, native forest) on the chemical properties of the soil (0-40 cm) in the mesoregion of the Juruá Valley, in the state of Acre, Brazil. Principal component analysis showed the soil in the forested area (reference) has greater values for P, Ca2+, Mg2+, K+, Na+, sum of bases, and cation exchange capacity; while hierarchical cluster analysis suggested little dissimilarity to the soil in the agroforestry system, and high dissimilarity to the soil in the areas of cassava cultivation and pasture. The results therefore support agroforestry as the most sustainable land use system, compared to cassava cultivation or pasture.

Resumo em Inglês:

ABSTRACT In this study, the objective was to determine the post-harvest indexes of arugula leaves and beet roots in intercropping under a biomass mixture of different green manures at diverse arugula population densities in two cropping seasons in a semi-arid environment. The experimental design was a randomised complete block design, with treatments arranged in a 4 × 4 factorial scheme with four replications. Treatments consisted of the combination of equitable amounts of Merremia aegyptia and Calotropis procera biomass (20, 35, 50 and 65 t ha-1 on a dry basis) and arugula population densities (400,000, 600,000, 800,000 and 1,000,000 plants ha-1). The characteristics evaluated in the arugula culture were titratable acidity, pH, and soluble solid and total soluble sugar content. In the beet crop, the same characteristics were evaluated in arugula, in addition to the betalain concentration and the internal colour parameters of the tuberose roots. Arugula showed the best post-harvest indexes when fertilised with green manure biomass amounts of 20, 20 and 65 t ha-1 at a population density of 1,000,000 plants ha-1, while beet showed the best indices with green manure amounts of 65, 41, 36 and 40 t ha-1 with an arugula density of 1,000,000 plants ha-1. The best colour parameters of beet roots were obtained with green manure amounts of 30 and 32 t ha-1 at an arugula density of 400,000 plants ha-1.

Resumo em Inglês:

ABSTRACT The aim of this study was use the performance prediction of crosses in a group of conventional soybean genotypes to obtain the breeding value (BV), and to evaluate the correlation between the prediction and the actual productive potential of the progeny generated by this method in experimental tests for different seasons and environments, and determine whether the methodology is efficient in generating progeny of high productive potential for the soybean macro-regions (SMR) and soil and climate regions (SCR) of Brazil. A total of 481 conventional elite genotypes were selected as parents, the BV were generated, and crosses were predicted using the restricted maximum likelihood/best linear unbiased prediction mixed-model procedure (REML/BLUP). In 2019, the predicted crosses and advancement of the F1 and F2 segregating populations were carried and sent to the breeding programs of a private company in Passo Fundo-RS, Cambé-PR, Rio Verde-GO, Lucas do Rio Verde-MT and Porto Nacional-TO, where they were sown during the 2019/2020 crop season. During the 2020/2021 season, 1868 progeny were selected and tested in experimental trials at these locations. The progeny were again tested during the 2021/2022 season in experimental trials in 50 environments in SCR throughout Brazil. The result of the analysis showed a very weak to moderate correlation, indicating little efficiency for the prediction model used in this study. It is suggested that the prediction model be revised to include a greater number of variables, such as the kinship matrix, so that the BV of the genotypes can be more assertively estimated, especially when the aim is to select progeny in early generations with a high degree of heterozygosity.