Instituto de Ciências Agrárias – CRP
URI permanente desta comunidadehttps://locus.ufv.br/handle/123456789/11787
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Resultados da Pesquisa
Item SPEED Stat: a free, intuitive, and minimalist spreadsheet program for statistical analyses of experiments(Crop Breeding and Applied Biotechnology, 2020) Carvalho, André Mundstock Xavier de; Mendes, Felipe Queiroz; Mendes, Fabrícia Queiroz; Tavares, Laene de FátimaSPEED Stat is a new spreadsheet program for univariate statistical analyses, focused on the dominant profile of agricultural experimentation. The program can perform analysis of variance; tests for normality, homoscedasticity, additivity, outliers; complex contrasts; multiple comparison tests; Scott-Knott's grouping analysis; regression analysis; and others. It has available at speedstatsoftware.wordpress.com.Item Associação de agrotóxicos aos teores foliares de micronutrientes e à produtividade e qualidade fisiológica de sementes de soja(Pesquisa Agropecuária Tropical, 2011-10) Reis, Marcelo Rodrigues; Silva, Antonio Alberto; Freitas, Marco Antonio Moreira; Pereira, Marcio Dias; Galon, Leandro; França, André Cabral; Pereira, Jardel LopesEfeitos do glyphosate nos teores foliares de micro-nutrientes de soja transgênica têm sido amplamente relatados, porém, pouco se sabe sobre seus efeitos associados a outros agrotóxicos. Objetivou-se, neste trabalho, avaliar a produção e a qualidade fisiológica de sementes de soja, bem como os teores de micronutrientes nas folhas, em função de métodos de controle de plantas daninhas. Foram avaliados dez tratamentos DBC, em esquema de parcelas subdivididas, com quatro repetições. Nas parcelas, avaliou-se o efeito da aplicação ou não de endossulfan + tebuconazole e, nas subparcelas, o efeito dos métodos de controle de plantas daninhas (testemunha não capinada; testemunha capinada; aplicação única de glyphosate (1.080 g ha-1) e fomesafen + fluazifop-ρ-butil (180 + 225 g ha-1), ambas aos 15 DAE; e aplicação sequencial de glyphosate (1.080 g ha-1), aos 15, 30 e 45 DAE). Após a colheita da soja, as sementes foram amostradas, para avaliar a sua germinação, vigor e produtividade. Os teores de manganês foram influenciados pela aplicação sequencial de glyphosate, associada ao endossulfan + tebuconazole. A germinação do teste de frio foi reduzida em sementes de plantas tratadas com fomesafen + fluazifop-p-butil, em associação com endossulfan + tebuconazole. Dentre os tratamentos sem endossulfan + tebuconazole, a aplicação sequencial de glyphosate promoveu a maior massa de cem sementes, bem como, associada à mistura endossulfan + tebuconazole, diminuiu os teores foliares de Cu e Mn, porém, melhorou a germinação e não influenciou no vigor das sementes, em relação à soja capinada.Item Propolis extract in postharvest conservation banana 'prata'(Revista Brasileira de Fruticultura, 2016-03) Passos, Flávia Regina; Mendes, Fabrícia Queiroz; Cunha, Mariana Crivelari da; Pigozzi, Mariana Teixeira; Carvalho, André Mundstock Xavier deIn the present work were evaluated the effects of propolis coatings of various botanical sources on quality traits of bananas cv. Prata (Musa sapientum L.) stored at room temperature. ´Prata´ bananas were selected and submitted to five postharvest treatments: four coatings applied by immersion in propolis extracts at a concentration of 2.5% (w/v) and a control (without coating). Propolis extracts were applied as 1) a wild type aqueous propolis extract, 2) a wild type hydroalcoholic propolis extract, 3) a rosemary green type hydroalcoholic propolis extract and 4) a red type hydroalcoholic propolis extract. The bananas were evaluated at three-day intervals along 12 days for fresh weight losses, flesh firmness, soluble solids (SS), titratable acidity (TA), the ratio SS/TA and pH. Sensory analyses were performed after three and six days of storage by 55 not trained panelists designed for acceptability. At the end of the twelve-day storage period, bananas coated either with the rosemary green hydroalcoholic extract or with the aqueous extract presented lower fresh weight losses in comparison to the bananas of the control treatment. No differences were determined in relation to flesh firmness and along the storage period TA values decreased and pH values increased in bananas of all treatments. SS contents increased towards the end of the storage period that, consequently, contributed to increases in the SS/TA ratio. The most significant increase in SS/TA ratio was determined in bananas coated with the red type hydroalcoholic extract. Taste panelists did not detect significant differences amongst coated and not coated cv. Prata bananas up to six days of storage.Item Nanopartículas de prata: método alternativo de sanitização para couve minimamente processada(Pesquisa Agropecuária Tropical, 2015-04) Passos, Flávia Regina; Ribeiro, Lorena; Pereira, Adayane Aparecida; Fialho Júnior, José Felício QueirozO processamento mínimo de hortaliças visa, basicamente, a estender a vida útil dos alimentos, o que depende de uma série de fatores, como, por exemplo, a sanitização, a qual é considerada etapa fundamental para a qualidade microbiológica do alimento. No entanto, os agentes antimicrobianos usuais reduzem a população microbiana em, no máximo, dois ciclos logarítmicos. Dessa forma, existe a necessidade de desenvolvimento de sanitizantes alternativos. O presente trabalho objetivou aumentar a inocuidade de couve minimamente processada, por meio de sanitização com nanopartículas de prata. Observou-se que as nanopartículas promoveram três reduções logarítmicas, ou seja, 99,9 % de redução, na população de Escherichia coli inoculada na superfície da couve. Quando comparadas com outros agentes antimicrobianos (dicloroisocianurato de sódio e hipoclorito de sódio), as nanopartículas mostraram-se mais eficientes na sanitização da couve minimamente processada, apresentando menor contagem de mesófilos aeróbios. Observou-se, também, que a superfície da couve apresenta características hidrofóbicas, resultando em maior propensão para adesão bacteriana, o que foi confirmado na avaliação da termodinâmica de adesão favorável para Staphylococcus aureus, Escherichia coli e Listeria innocua.Item Flight movement and spatial distribution of immunomarked thrips in onion, potato, and tomato(Pesquisa Agropecuária Brasileira, 2015-05) Fernandes, Flávio Lemes; Fernandes, Maria Elisa de SenaThe objective of this work was to evaluate the spatial distribution of thrips in different crops, and the correlation between meterological parameters and the flight movements of this pest, using immunomarking. The experiment was conducted in cultivated areas, with tomato (Solanum lycopersicum), potato (Solanum tuberosum), and onion (Allium cepa); and non-cultivated areas, with weedy plants. The areas with tomato (100 days), potato (20 days), and weeds were sprayed with casein, albumin, and soy milk, respectively, to mark adult thrips; however, the areas with onion (50 days) and tomato (10 days) were not sprayed. Thrips were captured with georeferenced blue sticky traps, transferred into tubes, and identified by treatment area with the Elisa test. The dependence between the samples and the capture distance was determined using geostatistics. Meteorlogical parameters were correlated with thrips density in each area. The three protein types used for immunomarking were detected in different proportions in the thrips. There was a correlation between casein-marked thrips and wind speed. The thrips flew a maximum distance of 3.5 km and dispersed from the older (tomato) to the younger crops (potato). The immunomarking method is efficient to mark large quantities of thrips.Item Foliar indices for carrot crop using the compositional nutrient diagnosis method(Pesquisa Agropecuária Tropical, 2017-10) Reis, Marcelo Rodrigues dos; Aquino, Leonardo Angelo de; Silva, Frederico Dellano Souza; Silva, Natalia Oliveira; Oliveira, Thaísa FernandaCarrot has a high yield potential, which requires an adequate and adaptable nutritional management, according to the needs and demands of each crop. Foliar diagnosis is a tool for adjustment and constant improvement of crop fertilization programs. This study aimed to determine leaf indices and reference values using the compositional nutrient diagnosis (CND) method, at three phenological stages of carrot crops [40 and 70 days after sowing (DAS) and at harvest]. In order to calculate the CND method, a database was created with leaf contents of the nutrients N, P, K, Ca, Mg, S, B, Cu, Mn and Zn and root yields, in commercial carrot crops. The nutrient limitation order was generated according to the fertilization response potential. At 70 DAS and at harvest, Mg and Mn were the most limiting nutrients by deficiency, while Zn was the most limiting by excess at 70 DAS, and P and Ca were the most limiting by excess at harvest. The results indicate that the foliar diagnosis performed with the CND method is only effective for the correction of nutritional disturbances in subsequent crops.Item Ação nematicida do eugenol em tomateiro(Pesquisa Agropecuária Tropical, 2013-07) Moreira, Lara Caroline Borges; Vieira, Bruno Sérgio; Mota Júnior, Célio Vinícius da; Lopes, Everaldo Antônio; Canedo, Ellen JúniaÓleos essenciais de várias espécies de plantas possuem propriedades nematicidas e poderiam ser utilizados no controle do nematoide das galhas. Desta forma, esta pesquisa objetivou avaliar o efeito da aplicação de concentrações de eugenol no controle de Meloidogyne incognita e Meloidogyne javanica, em casa-de-vegetação. O eugenol foi aplicado nas concentrações de 0,25 mL L-1, 0,50 mL L-1, 0,75 mL L-1 e 1,00 mL L-1, na forma de pulverização foliar ou adição ao solo. O delineamento experimental foi inteiramente casualizado, em arranjo fatorial 4 x 2 + 1 (concentrações de eugenol x formas de aplicação + testemunha – tratamento adicional), com cinco repetições. Os números de galhas e de ovos de M. incognita e de ovos de M. javanica foram reduzidos em plantas tratadas com eugenol, em comparação com a testemunha. A adição ao solo foi o método mais eficiente de aplicação do eugenol, considerando-se a redução no número de galhas. Houve efeito significativo do aumento de concentrações de eugenol na redução do número de ovos de M. incognita. O eugenol apresenta potencial para ser utilizado no manejo do nematoide das galhas, embora novos estudos ainda sejam necessários para suportar tal expectativa.Item Influence of spray drying operating conditions on microencapsulated rosemary essential oil properties(Food Science and Technology, 2013-02) Fernandes, Regiane Victória de Barros; Borges, Soraia Vilela; Botrel, Diego AlvarengaSpray drying is an important method used by the food industry in the production of microencapsulated flavors to improve handling and dispersion properties. The objective of this study was to evaluate the influence of the process conditions on the properties of rosemary essential oil microencapsulated by spray drying using gum Arabic as encapsulant. The effects of the wall material concentration (10-30%), inlet air temperature (135-195 ºC), and feed flow rate (0.5-1.0 L.h-1) on the moisture content, hygroscopicity, wettability, solubility, bulk and tapped densities, particle density, flowability, and cohesiveness were evaluated using a 23 central composite rotational experimental design. Moisture content, hygroscopicity and wettability were significantly affected by the three factors analyzed. Bulk density was positively influenced by the wall material concentration and negatively by the inlet air temperature. Particle density was influenced by the wall material concentration and the inlet air temperature variables, both in a negative manner. As for the solubility, tapped density, flowability, and cohesiveness, the models did not fit the data well. The results indicated that moderate wall material concentration (24%), low inlet air temperature (135 ºC), and moderate feed flow rate (0.7 L.h-1) are the best spray drying conditions.Item Mechanical harvesting of coffee in high slope(Revista Caatinga, 2016-07) Santonato, Felipe; Silva, Rouverson Pereira da; Silva, Vantuir de Albuquerque; Silva, Carlos Diego da; Tavares, Tiago de OliveiraBrazilian coffee farming is carried out both on flat and steep lands. In flat areas, mechanized operations are intensive; however, in steep slope areas, certain mechanized operations cannot be performed, such as harvesting. Based on this, the industry has developed machinery to harvest coffee in areas with up to 30% slope. However, harvesters have their efficiency and operational performance influenced by land slope. Thus, this study aimed to evaluate the operational performance and harvesting efficiency of a steep -slope harvester under different situations, using different speed settings. The experiment was carried out in the county of Santo Antônio do Amparo, state of Minas Gerais, Brazil, using five coffee stands with 10, 15, 20, 25 and 30% slope. Evaluations were performed with a self-propelled harvester (Electron, TDI(r), Araguari, MG, Brazil) at three rotation speeds (600, 800 and 1.000 rpm) and two ground speeds (800 and 1.000 m h -1). The results showed the lower speed (800 m h-1) was suitable for 10% slope areas since the amount of fallen coffee berries. For areas of 20% slope, harvesting time was 21.6% longer than in flatter areas. Downtime varied from 10.66 to 29.18% total harvest due to a higher number of maneuvers.Item The epiphytic orchids Ionopsis utricularioides and Psygmorchis pusilla associate with different Ceratobasidium lineages at Valle del Cauca, Colombia(Acta Botanica Brasilica, 2015-01) Pereira, Marlon Corrêa; Valadares, Rafael Borges da Silva; Otero, Joel Tupac; Cardoso, Elke Jurandy Bran NogueiraIn Orchidaceae, association with symbiotic fungi is required for seed germination and seedling development, thereby being the main energy source during the first steps of germination. Colombia is one of the countries with the greatest biodiversity of orchids, with an estimated 3,200 species, but few studies on orchid mycorrhiza have been conducted. In our study, we isolated and sequenced the internal transcribed spacer rDNA region of fungi from two co-occurring Colombian epiphytic orchids, I. utricularioides and P. pusilla, both belonging to the subtribe Oncidiinae. All sequences were recognized as belonging to the genus Ceratobasidium, known to be a common orchid mycorrhizal fungus in both tropical and temperate orchids. One sequence was 100% similar to fungi isolated from I. utricularioides in Costa Rica in a previous study. I. utricularioides was confirmed to be a specialist, associating with only one clade of mycorrhizal fungi. However, P. pusilla was shown to be a generalist, associating with three clades. This finding indicates that the variation in mycorrhizal specificity could be an important factor in the co-existence of orchids. The high affinity between the subtribe Oncidiinae and Ceratobasidium was also reinforced.