25 research outputs found

    CENTRIFUGATION METHODOLOGY TO EXTRACT SOIL SOLUTION

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    The quantification of ions and compounds present in the soil solution is extremely difficult and requires standard extraction and quantification techniques. The present work describes in detail the equipment and procedures required to extract the soil solution by the centrifugation method of deformed soil samples and analyzes its application in soils with different granulometry. This description of centrifugation method and the Centrifuge 1.0 software are useful tools to author that desire a quickly and economically method to obtain the soil solution. We emphasize that there is no consensus on the best method of obtaining the soil solution, but is clear the need for the authors to explain how they obtained it

    Short communication: Genetic parameters for post-weaning visual scores and reproductive traits in Suffolk sheep

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              The aim of this study was to estimate the coefficients of heritability and genetic correlations among visual scores (conformation, CPW; precocity, PPW; musculature, MPW) and reproductive traits: age at first lambing (AFL) and scrotal circumference (SC) evaluated at 180 days of age in Suffolk lambs. In the statistical model only the additive genetic effect was considered as random effect. The heritability estimates by univariate analyses for CPW, PPW, MPW, AFL and SC were 0.08, 0.12, 0.09, 0.20 and 0.22, respectively. The genetic correlations among AFL and CPW, PPW, MPW were -0.26, 0.19, and 0.08, respectively. The genetic correlation among SC and CPW, PPW, MPW were, respectively, 0.54, 0.88 and 0.86, and between AFL and SC was 0.26. The direct selection for conformation, precocity and musculature at 180 days of age and age at first lambing will provide slow genetic progress due to low heritability estimates. It is possible to obtain genetic gain in sexual precocity through selection on scrotal circumference in Suffolk rams. The favorable genetic correlation among visual scores and SC and between CPW and AFL, indicated the possibility to gain in genetic progress for reproductive traits through indirect selection of the visual scores in Suffolk sheep

    ANÁLISE DE SUPERAÇÃO DE DORMÊNCIA DE SEMENTES DE LEUCAENA LEUCOCEPHALA E DESENVOLVIMENTO INICIAL DE PLÂNTULAS

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    A leucena é uma fabaceae exótica que possui utilização bastante diversificada, destacando-se no reflorestamento de áreas degradadas para controle de erosão. Por apresentar um crescimento inicial bastante lento, o sucesso de seu cultivo está relacionado com a semeadura e emergência das sementes, que por sua vez requer a utilização de métodos de superação de dormência física para obter êxito. O presente trabalho buscou avaliar o efeito de métodos de superação da dormência na germinação de sementes e no desenvolvimento inicial de plântulas de leucena. Os tratamentos utilizados foram: Testemunha (sem intervenção); escarificação mecânica com lixa nº 100; imersão em H2SO4 (95 %) por 4 minutos e imersão em H2O a 80°C por 15 minutos.  A escarificação mecânica com lixa e a água a 80ºC por 15 minutos apresentaram os melhores resultados para porcentagem de germinação. Já, para índice de velocidade de emergência, a escarificação foi superior

    Soil chemical attributes and sunflower and maize yield according to the application of urban waste compost

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    The use of composted urban waste as a source of nutrients in agriculture is an economic alternative for discarding this material. However, due to the diversity of materials that compose this waste, long term studies on its effects on soil chemical attributes and crop yield are necessary. This study aimed at evaluating the potential of urban waste compost (UWC) as a fertilizer for sunflower and maize crops, as well as its effects on the chemical attributes of an Oxisol. A field experiment, with UWC doses of 0 Mg ha-1, 10 Mg ha-1, 20 Mg ha-1, 30 Mg ha-1 and 40 Mg ha-1 and mineral fertilization according to the recommendation for each crop, was carried out. The results showed an increase in soil pH from 6 to 6.5, with the UWC application. The soil potential acidity decreased linearly from 3.0 cmolc dm-3 to 2.4 cmolc dm-3, contributing to the SMP index increase, what reflected on the increase of the soil cation exchange capacity. The bases saturation increased from 77% to 85%, mainly due to the increase in calcium and magnesium levels. The use of UWC resulted in sunflower grain yield similar to that for mineral fertilization, at 10 Mg ha-1, 20 Mg ha-1 and 30 Mg ha-1, being significantly higher at 40 Mg ha-1. The maize grain yield at or above 20 Mg ha-1 of UWC did not differ from the mineral fertilization. The UWC presented potential to replace the mineral fertilization for sunflower and maize crops

    Alterações da temperatura em solo coberto de palha de aveia-preta

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    The objective of this work was to evaluate the effect of different amounts of black oat (Avena strigosa) straw covering soil surface on soil temperature at different depths. The treatments consisted of 0, 3, 6, and 9 Mg ha-1 straw. Soil temperature was measured hourly by a thermocouple inserted at different depths (0, 5, 15, 30, and 50 cm) and was used to adjust an equation correlating the temperature of covered soil with that of bare soil. With the correlations, it was possible to observe a point value of temperature (inversion temperature of straw effect), below which the presence of straw acts positively on the maintenance of soil temperature and above which the presence of straw acts negatively on soil heating.O objetivo deste trabalho foi avaliar o efeito de diferentes quantidades de palha de aveia-preta (Avena strigosa) em cobertura do solo sobre a temperatura do solo em diferentes profundidades. Os tratamentos consistiram de 0, 3, 6 e 9 Mg ha-1 de palha. A temperatura do solo foi medida a cada hora por meio de termopares inseridos em diferentes profundidades (0, 5, 15, 30 e 50 cm) e usada para ajustar uma equação que correlaciona a temperatura do solo coberto com a do solo descoberto. A partir dessas correlações, foi possível observar um valor pontual de temperatura (temperatura de inversão do efeito da palha), abaixo do qual a presença de palha atua positivamente na manutenção da temperatura do solo e acima do qual a presença de palha atua negativamente no aquecimento do solo

    Hexapoda Yearbook (Arthropoda: Mandibulata: Pancrustacea) Brazil 2020: the first annual production survey of new Brazilian species

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    This paper provided a list of all new Brazilian Hexapoda species described in 2020. Furthermore, based on the information extracted by this list, we tackled additional questions regarding the taxa, the specialists involved in the species descriptions as well as the journals in which those papers have been published. We recorded a total of 680 new Brazilian species of Hexapoda described in 2020, classified in 245 genera, 112 families and 18 orders. These 680 species were published in a total of 219 articles comprising 423 different authors residing in 27 countries. Only 30% of these authors are women, which demonstrates an inequality regarding sexes. In relation to the number of authors by species, the majority of the new species had two authors and the maximum of authors by species was five. We also found inequalities in the production of described species regarding the regions of Brazil, with Southeast and South leading. The top 10 institutions regarding productions of new species have four in the Southeast, two at South and with one ate North Region being the outlier of this pattern. Out of the total 219 published articles, Zootaxa dominated with 322 described species in 95 articles. The average impact factor was of 1.4 with only seven articles being published in Impact Factors above 3, indicating a hardship on publishing taxonomic articles in high-impact journals.The highlight of this paper is that it is unprecedent, as no annual record of Hexapoda species described was ever made in previous years to Brazil.Fil: Silva Neto, Alberto Moreira. Ministério da Ciência, Tecnologia, Inovações. Instituto Nacional de Pesquisas da Amazônia; BrasilFil: Lopes Falaschi, Rafaela. Universidade Estadual do Ponta Grossa; BrasilFil: Zacca, Thamara. Universidade Federal Do Rio de Janeiro. Museu Nacional; BrasilFil: Hipólito, Juliana. Universidade Federal da Bahia; BrasilFil: Costa Lima Pequeno, Pedro Aurélio. Universidade Federal de Roraima; BrasilFil: Alves Oliveira, João Rafael. Ministério da Ciência, Tecnologia, Inovações. Instituto Nacional de Pesquisas da Amazônia; BrasilFil: Oliveira Dos Santos, Roberto. Ministério da Ciência, Tecnologia, Inovações. Instituto Nacional de Pesquisas da Amazônia; BrasilFil: Heleodoro, Raphael Aquino. Ministério da Ciência, Tecnologia, Inovações. Instituto Nacional de Pesquisas da Amazônia; BrasilFil: Jacobina, Adaiane Catarina Marcondes. Universidade Federal do Paraná; BrasilFil: Somavilla, Alexandre. Ministério da Ciência, Tecnologia, Inovações. Instituto Nacional de Pesquisas da Amazônia; BrasilFil: Camargo, Alexssandro. Ministério da Ciência, Tecnologia, Inovações. Instituto Nacional de Pesquisas da Amazônia; BrasilFil: de Oliveira Lira, Aline. Universidad Federal Rural Pernambuco; BrasilFil: Sampaio, Aline Amanda. Ministério da Ciência, Tecnologia, Inovações. Instituto Nacional de Pesquisas da Amazônia; BrasilFil: da Silva Ferreira, André. Universidad Federal Rural Pernambuco; BrasilFil: Martins, André Luis. Universidade Federal do Paraná; BrasilFil: Figueiredo de Oliveira, Andressa. Universidade Federal do Mato Grosso do Sul; BrasilFil: Gonçalves da Silva Wengrat , Ana Paula. Universidade do Sao Paulo. Escola Superior de Agricultura Luiz de Queiroz; BrasilFil: Batista Rosa, Augusto Henrique. Universidade Estadual de Campinas; BrasilFil: Dias Corrêa, Caio Cezar. Universidade Federal Do Rio de Janeiro. Museu Nacional; BrasilFil: Costa De-Souza, Caroline. Museu Paraense Emilio Goeldi; BrasilFil: Anjos Dos Santos, Danielle. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagónica. Universidad Nacional de la Patagonia "San Juan Bosco". Centro de Investigación Esquel de Montaña y Estepa Patagónica; ArgentinaFil: Pacheco Cordeiro, Danilo. Instituto Nacional Da Mata Atlantica; BrasilFil: Silva Nogueira, David. Ministério da Ciência, Tecnologia, Inovações. Instituto Nacional de Pesquisas da Amazônia; BrasilFil: Almeida Marques, Dayse Willkenia. Ministério da Ciência, Tecnologia, Inovações. Instituto Nacional de Pesquisas da Amazônia; BrasilFil: Nunes Barbosa, Diego. Universidade Federal do Paraná; BrasilFil: Mello Mendes, Diego Matheus. Instituto de Desenvolvimento Sustentável Mamirauá; BrasilFil: Galvão de Pádua, Diego. Ministério da Ciência, Tecnologia, Inovações. Instituto Nacional de Pesquisas da Amazônia; BrasilFil: Silva Vilela, Diogo. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Gomes Viegas, Eduarda Fernanda. Ministério da Ciência, Tecnologia, Inovações. Instituto Nacional de Pesquisas da Amazônia; BrasilFil: Carneiro dos Santos, Eduardo. Universidade Federal do Paraná; BrasilFil: Rodrigues Fernandes, Daniell Rodrigo. Ministério da Ciência, Tecnologia, Inovações. Instituto Nacional de Pesquisas da Amazônia; Brasi

    Dynamique temporelle du P dans des sols avec des usages différents en climat tempéré et subtropical

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    The prospect of world population increases requires that the production of food to be potentialized and better distributed around the world. One sustainable alternative to achieve high food production is an efficient use of the areas already cultivated. Phosphorus (P) is an essential nutrient for plant production whose natural reserves are threatened with depletion in the coming decades. Thus, the adequate use of this nutrient is mandatory to achieve sustainability in agriculture and environment. Thus, this work is placed in the scenario of increasing fertilizer efficiency, raising agricultural production, and maintaining the dynamic balance of nutrients aiming at the sustainability of agricultural systems, food security and reduction of climate change. Therefore, the main objective of this These was establishing a more effective strategy of P fertilization on increase forage production, maintenance of plant community and efficiency use of P. As well as, testing the effect of soil management systems on soil P availability and depletion and their stoichiometry with carbon and nitrogen in soil. To achieve our objectives, we analyzed two long-term experiments. The first one was established in 1997 in a natural grassland of Pampa biome, Rio Grande do Sul, Brazil. The soil of this experiment is a phosphorus-poor soil with low total and available P stocks. In this site the effect different P sources were tested by analysing historical dry-matter production, P use efficiency and botanical changes. The second one was established in 2005 in an agricultural soil situated in ORE ACBB at INRAe in Lusignan, France. The experimental soil had high total and available P stocks due to an historic fertilization before experiment. The studies on this site were focused on the long term effect of two management systems (permanent cropland and permanent grassland) by field, P exportation, soil P, C and N total stocks depletion, P availability depletion and changes in soil C:N:P stoichiometry. The dynamic of P in soil microbial biomass and alteration of P, C and N coupling in soil aggregate sizes. We concluded that the use of soluble P sources (such as simple and triple superphosphate) associated with liming is a better strategy to improve dry matter production and P use efficiency in Pampa grassland. These fertilizers lead to a small change in species richness; however, there was higher species turnover, mainly in the tussock grass and forbs groups and in the legume contribution to forage production. To maintain dry matter yield, a regular phosphorus input with no more than three years is necessary. Though, the use of natural phosphates (phosphate rocks) did not improve fertility conditions and dry matter production satisfactorily due to their long term non dissolution (more than six years). In soil with high P stock, permanent grassland provided a greater depletion of total and P-labile stocks than permanent cropland. As well, permanent grassland supports a transformation from inorganic P to organic P in the most labile pool, accompanying the increase of C and N stocks in the soil. Additionally, we observed that the Pmic is an important bioavailable P pool in both management systems and accounted for up to 47% of the available P content (P Olsen) in a permanent cropland system. By 31P-NMR technique was observed that permanent grassland had a more significant effect in reducing α–glycerophosphate and increasing myo-IHP and adenosine monophosphate than permanent cropland.La perspective d'une augmentation de la population mondiale implique que la production alimentaire soit améliorée et mieux répartie dans le monde. Une alternative durable pour atteindre une production alimentaire élevée est une utilisation efficace des surfaces déjà cultivées. Le phosphore (P) est un élément nutritif essentiel à la production végétale dont les réserves naturelles sont menacées d'épuisement dans les prochaines décennies. L'utilisation adéquate de ce nutriment est donc nécessaire pour assurer la durabilité de l'agriculture et de l'environnement. Ainsi, ce travail s'inscrit dans le scénario d'augmentation de l'efficacité des engrais et de la production agricole et de maintien de l'équilibre dynamique des nutriments en visant la durabilité des systèmes agricoles, la sécurité alimentaire et la réduction du changement climatique. Par conséquent, l'objectif principal de ces travaux était d'établir une stratégie plus efficace de fertilisation au P pour augmenter la production de fourrage, le maintien de la communauté végétale et l'utilisation efficace du P. De même, nous avons testé l'effet des systèmes de gestion du sol sur la disponibilité et l'épuisement du P dans le sol et sa stœchiométrie avec le carbone et l'azote. Pour atteindre nos objectifs, nous avons analysé deux expériences de long terme. La première a été établie en 1997 dans une prairie naturelle du biome de la Pampa dans l’état du Rio Grande do Sul au Brésil. Le sol du site expérimental est un sol avec de faibles stocks de P total et disponible. Sur ce site, l’effet de différentes sources de P a été testé sur la production de matière sèche, l'efficacité de l'utilisation du P par les plantes et les changements botaniques. Le second site, établi en 2005, est situé sur le site expérimental de l’ORE ACBB de l’INRAe de Lusignan en France. Le sol du site expérimental présentait des stocks élevés de P total et disponible en raison d'une fertilisation historique avant l'expérience. Aucune fertilisation P n’a été réalisée depuis l’installation du site expérimental. Sur ce site, l'effet à long terme de deux systèmes de gestion (culture permanente et prairie permanente) a été mesuré par l'exportation de P, l'épuisement des stocks totaux de P, C et N du sol, le suivi de la disponibilité du P et les changements dans la stœchiométrie C:N:P du sol. La dynamique du P dans la biomasse microbienne du sol et les modifications du couplage P, C et N dans la taille des agrégats du sol ont également été suivies. Nous avons conclu que l'utilisation de sources de P soluble (comme le superphosphate simple et triple) associée au chaulage est une meilleure stratégie pour améliorer la production de matière sèche et l'efficacité d'utilisation du P dans les prairies de la Pampa. Ces engrais ont entraîné un léger changement dans la richesse des espèces ; cependant, il y a eu un plus grand renouvellement des espèces, principalement dans les groupes de graminées et de plantes fourragères et dans la contribution des légumineuses à la production de fourrage. Pour maintenir le rendement en matière sèche, un apport régulier de phosphore, ne dépassant pas trois ans, est nécessaire. L'utilisation de phosphates naturels (roches phosphatées) n'a pas permis d'améliorer la fertilité et la production de matière sèche de manière satisfaisante en raison de leur non-dissolution à long terme (plus de six ans). D'autre part, les prairies permanentes ont entraîné un plus grand épuisement des stocks totaux et P-labile en comparaison des cultures permanentes. De même, les prairies permanentes ont favorisé une transformation du P inorganique en P organique dans le pool le plus labile, accompagnant l'augmentation des stocks de C et de N dans le sol. La technique RMN 31P a permis d'observer que les prairies permanentes avaient un effet plus significatif sur la réduction de l'α-glycérophosphate et l'augmentation du myo-IHP et de l'adénosine monophosphate que les terres cultivées permanentes

    Dynamique temporelle du P dans des sols avec des usages différents en climat tempéré et subtropical

    No full text
    La perspective d'une augmentation de la population mondiale implique que la production alimentaire soit améliorée et mieux répartie dans le monde. Une alternative durable pour atteindre une production alimentaire élevée est une utilisation efficace des surfaces déjà cultivées. Le phosphore (P) est un élément nutritif essentiel à la production végétale dont les réserves naturelles sont menacées d'épuisement dans les prochaines décennies. L'utilisation adéquate de ce nutriment est donc nécessaire pour assurer la durabilité de l'agriculture et de l'environnement. Ainsi, ce travail s'inscrit dans le scénario d'augmentation de l'efficacité des engrais et de la production agricole et de maintien de l'équilibre dynamique des nutriments en visant la durabilité des systèmes agricoles, la sécurité alimentaire et la réduction du changement climatique. Par conséquent, l'objectif principal de ces travaux était d'établir une stratégie plus efficace de fertilisation au P pour augmenter la production de fourrage, le maintien de la communauté végétale et l'utilisation efficace du P. De même, nous avons testé l'effet des systèmes de gestion du sol sur la disponibilité et l'épuisement du P dans le sol et sa stœchiométrie avec le carbone et l'azote. Pour atteindre nos objectifs, nous avons analysé deux expériences de long terme. La première a été établie en 1997 dans une prairie naturelle du biome de la Pampa dans l’état du Rio Grande do Sul au Brésil. Le sol du site expérimental est un sol avec de faibles stocks de P total et disponible. Sur ce site, l’effet de différentes sources de P a été testé sur la production de matière sèche, l'efficacité de l'utilisation du P par les plantes et les changements botaniques. Le second site, établi en 2005, est situé sur le site expérimental de l’ORE ACBB de l’INRAe de Lusignan en France. Le sol du site expérimental présentait des stocks élevés de P total et disponible en raison d'une fertilisation historique avant l'expérience. Aucune fertilisation P n’a été réalisée depuis l’installation du site expérimental. Sur ce site, l'effet à long terme de deux systèmes de gestion (culture permanente et prairie permanente) a été mesuré par l'exportation de P, l'épuisement des stocks totaux de P, C et N du sol, le suivi de la disponibilité du P et les changements dans la stœchiométrie C:N:P du sol. La dynamique du P dans la biomasse microbienne du sol et les modifications du couplage P, C et N dans la taille des agrégats du sol ont également été suivies. Nous avons conclu que l'utilisation de sources de P soluble (comme le superphosphate simple et triple) associée au chaulage est une meilleure stratégie pour améliorer la production de matière sèche et l'efficacité d'utilisation du P dans les prairies de la Pampa. Ces engrais ont entraîné un léger changement dans la richesse des espèces ; cependant, il y a eu un plus grand renouvellement des espèces, principalement dans les groupes de graminées et de plantes fourragères et dans la contribution des légumineuses à la production de fourrage. Pour maintenir le rendement en matière sèche, un apport régulier de phosphore, ne dépassant pas trois ans, est nécessaire. L'utilisation de phosphates naturels (roches phosphatées) n'a pas permis d'améliorer la fertilité et la production de matière sèche de manière satisfaisante en raison de leur non-dissolution à long terme (plus de six ans). D'autre part, les prairies permanentes ont entraîné un plus grand épuisement des stocks totaux et P-labile en comparaison des cultures permanentes. De même, les prairies permanentes ont favorisé une transformation du P inorganique en P organique dans le pool le plus labile, accompagnant l'augmentation des stocks de C et de N dans le sol. La technique RMN 31P a permis d'observer que les prairies permanentes avaient un effet plus significatif sur la réduction de l'α-glycérophosphate et l'augmentation du myo-IHP et de l'adénosine monophosphate que les terres cultivées permanentes.The prospect of world population increases requires that the production of food to be potentialized and better distributed around the world. One sustainable alternative to achieve high food production is an efficient use of the areas already cultivated. Phosphorus (P) is an essential nutrient for plant production whose natural reserves are threatened with depletion in the coming decades. Thus, the adequate use of this nutrient is mandatory to achieve sustainability in agriculture and environment. Thus, this work is placed in the scenario of increasing fertilizer efficiency, raising agricultural production, and maintaining the dynamic balance of nutrients aiming at the sustainability of agricultural systems, food security and reduction of climate change. Therefore, the main objective of this These was establishing a more effective strategy of P fertilization on increase forage production, maintenance of plant community and efficiency use of P. As well as, testing the effect of soil management systems on soil P availability and depletion and their stoichiometry with carbon and nitrogen in soil. To achieve our objectives, we analyzed two long-term experiments. The first one was established in 1997 in a natural grassland of Pampa biome, Rio Grande do Sul, Brazil. The soil of this experiment is a phosphorus-poor soil with low total and available P stocks. In this site the effect different P sources were tested by analysing historical dry-matter production, P use efficiency and botanical changes. The second one was established in 2005 in an agricultural soil situated in ORE ACBB at INRAe in Lusignan, France. The experimental soil had high total and available P stocks due to an historic fertilization before experiment. The studies on this site were focused on the long term effect of two management systems (permanent cropland and permanent grassland) by field, P exportation, soil P, C and N total stocks depletion, P availability depletion and changes in soil C:N:P stoichiometry. The dynamic of P in soil microbial biomass and alteration of P, C and N coupling in soil aggregate sizes. We concluded that the use of soluble P sources (such as simple and triple superphosphate) associated with liming is a better strategy to improve dry matter production and P use efficiency in Pampa grassland. These fertilizers lead to a small change in species richness; however, there was higher species turnover, mainly in the tussock grass and forbs groups and in the legume contribution to forage production. To maintain dry matter yield, a regular phosphorus input with no more than three years is necessary. Though, the use of natural phosphates (phosphate rocks) did not improve fertility conditions and dry matter production satisfactorily due to their long term non dissolution (more than six years). In soil with high P stock, permanent grassland provided a greater depletion of total and P-labile stocks than permanent cropland. As well, permanent grassland supports a transformation from inorganic P to organic P in the most labile pool, accompanying the increase of C and N stocks in the soil. Additionally, we observed that the Pmic is an important bioavailable P pool in both management systems and accounted for up to 47% of the available P content (P Olsen) in a permanent cropland system. By 31P-NMR technique was observed that permanent grassland had a more significant effect in reducing α–glycerophosphate and increasing myo-IHP and adenosine monophosphate than permanent cropland
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