RESUMO

The growth of cover crops can contribute to the increase in phosphorus content at depth by root decomposition. The aim of this work was to verify the effect of cover crops on soil phosphorus availability and use by successive plants, and the accumulation of soil P in a no-tillage system conducted for 14 years. This research was carried out during the 2016/2017 and 2017/2018 crop seasons, whose treatments have been installed and maintained since 2003. The experimental design was a randomized block design, and the plots consisted of spring crops: pearl millet, forage sorghum, sunn hemp, and additionally, a fallow/chiseling area. The evaluation of available P was determined by P fractionation. In general, in the two years of evaluation, the accumulation of P in the shoot dry matter was higher in sunn hemp growth, on average 25% higher than pearl millet in 2016 and 40% higher than sorghum in 2017. The highest contents of labile inorganic P were in the sorghum-soybean and fallow/chiseling-soybean successions, with values higher than 50 mg kg-1 of P in the 0-0.1 m soil layer. However, in the other layers analyzed, the cover crops obtained higher availability of labile inorganic P. The systems using cover crops recovered 100% of the P fertilized in soybean.

RESUMO

Environmental conditions affect crop yield, and water deficit has been highlighted by the negative impact on soybean grain production. Radicial growth in greater volume and depth can be an alternative to minimize losses caused by a lack of water. Therefore, knowledge of how soybean roots behave before the chemical, physical, and biological attributes of the soil can help establish managements that benefit in-depth root growth. The objective was to evaluate the growth of soybean roots in response to chemical, physical, and biological variations in the soil, in different soil locations and depths. Six experiments were conducted in different locations. Soil samples were collected every 5 cm of soil up to 60 cm of soil depth for chemical, physical, and biological analysis. The roots were collected every 5 cm deep up to 45 cm deep from the ground. The six sites presented unsatisfactory values of pH and organic matter, and presented phosphorus, potassium, and calcium at high concentrations in the first centimeters of soil depth. The total porosity of the soil was above 0.50 m3 m-3, but the proportion of the volume of macropores, micropores, and cryptopores resulted in soils with resistance to penetration to the roots. Microbial biomass was higher on the soil surface when compared to deeper soil layers, however, the metabolic quotient was higher in soil depth, showing that microorganisms in depth have low ability to incorporate carbon into microbial biomass. Root growth occurred in a greater proportion in the first centimeters of soil-depth, possibly because the soil attributes that favor the root growth is concentrated on the soil surface.

RESUMO

The study of adaptability and stability underlies the cultivar recommendation process for all crops. There is a considerable number of statistical methods available for this purpose, but little is known about their actual adoption by the Brazilian scientific community. The objective of this study was to carry out a systematic review of the scientific literature on the adaptability and stability methods used in maize and soybean in Brazil from scientific articles published between 1970 and 2017 in Brazilian journals. Article searches were carried out in journals indexed through the SciELO database. The articles were classified according to the year of publication and the adaptability and stability methods used. We also evaluated the pattern of association between methods. We found 113 articles on adaptability and stability in maize and soybean, in which 21 methods were listed. The most commonly used method was the Eberhart and Russell methodology. The Cruz, Torres, and Vencovsky along with the AMMI methods were also widely used. The number of articles using most methods decreased in the current decade, except for the GGE Biplot, MHPRVG, and Centroid methods. In studies with more than one method, the methods were more likely to be used together with the Eberhart and Russell methodology. Adaptability and stability in maize and soybean have been widely studied over the last several decades in Brazil, although the number of publications on this subject has decreased over this time period.(AU)

Assuntos

RESUMO

The study of adaptability and stability underlies the cultivar recommendation process for all crops. There is a considerable number of statistical methods available for this purpose, but little is known about their actual adoption by the Brazilian scientific community. The objective of this study was to carry out a systematic review of the scientific literature on the adaptability and stability methods used in maize and soybean in Brazil from scientific articles published between 1970 and 2017 in Brazilian journals. Article searches were carried out in journals indexed through the SciELO database. The articles were classified according to the year of publication and the adaptability and stability methods used. We also evaluated the pattern of association between methods. We found 113 articles on adaptability and stability in maize and soybean, in which 21 methods were listed. The most commonly used method was the Eberhart and Russell methodology. The Cruz, Torres, and Vencovsky along with the AMMI methods were also widely used. The number of articles using most methods decreased in the current decade, except for the GGE Biplot, MHPRVG, and Centroid methods. In studies with more than one method, the methods were more likely to be used together with the Eberhart and Russell methodology. Adaptability and stability in maize and soybean have been widely studied over the last several decades in Brazil, although the number of publications on this subject has decreased over this time period.

Assuntos

RESUMO

A sensitive and reliable process was established using high-performance liquid chromatography (HPLC) to distinguish conventional varieties of glyphosate-resistant genetically modified crops via shikimate detection in soybean (Glycine max L. Merril) seeds. Glyphosate has a well-defined mechanism of action. It is the only herbicide that specifically inhibits 5-enolpiruvilshikimate-3-phosphate synthase (EPSPS E.C. 2.5.1.19), which catalyzes the condensation of shikimate with phosphoenolpyruvate. This study is based on the concept that shikimate significantly accumulates in soybean plant tissues after EPSPS inhibition by glyphosate. In plants not subjected to glyphosate, shikimate is not easily detected because it quickly metabolizes into shikimate 3-phosphate and subsequently into 5-enolpiruvilshikimate 3-phosphate through the action of EPSPS. Conversely, in non-genetically modified plants subjected to glyphosate, shikimate metabolism is impaired, resulting in its accumulation. This metabolite can be detected in extremely low quantities (in the microgram range), through HPLC. In this study, six different contrasts were analyzed, each being formed by a transgenic cultivation and its parental strain, subject or not subject to the treatment of soaking with a 0.6% glyphosate solution. Chromatographic analyses indicated shikimate accumulation only in conventional cultivars with seeds previously soaked in a 0.6% glyphosate solution. Thus, this shikimate detection method can be used as a rapid and accurate means to distinguish soybeans with glyphosate-resistant qualities.

Este estudo estabelece um processo, sensível e confiável, com aplicação de cromatografia líquida de alta eficiência (HPLC) para distinguir variedades de soja convencionais de geneticamente modificadas, resistentes ao glifosato, por detecção de chiquimato nas sementes. O mecanismo de ação doglifosato é bem definido. É o único herbicida que inibe especificamente a enzima 5-enolpiruvilchiquimato-3-fosfato sintase (EPSPS, E.C. 2.5.1.19), que catalisa a condensação do chiquimato com fosfoenolpiruvato. O trabalho está baseado na concepção do chiquimato se acumular significativamente nos tecidos vegetais de soja convencional, após a inibição da EPSP sintase pelo glifosato. Em plantas não submetidas ao glifosato, o chiquimato não é facilmente detectado, pois rapidamente é metabolizado a chiquimato 3-fosfato e, a seguir, em 5-enolpiruvilchiquimato 3-fosfato, pela ação da EPSPS. Por outro lado, em plantas não geneticamente modificadas submetidas ao glifosato, a metabolização do chiquimato é prejudicada, resultando em seu acúmulo. Este metabólito pode ser detectado em quantidades extremamente baixas (na faixa de µg), por HPLC. Neste trabalho foram analisados seis contrastes diferentes, sendo cada contraste formado por uma cultivar transgênica e sua respectiva cultivar parental convencional, submetidas ou não a embebição com solução de glifosato 0,6%. As análises cromatográficas indicaram o acúmulo de chiquimato apenas em cultivares convencionais, nas quais as sementes foram previamente embebidas em solução de glifosato 0,6%. Os resultados demonstraram que adetecção de chiquimato pode ser utilizada como um método rápido e preciso na diferenciação de soja resistente ao glifosato de soja convencional.

Assuntos

RESUMO

Asian soybean rust is an aggressive disease and chemical control must be handled assertively to minimize productivity damage. The objective was to evaluate systemic fungicides and multisite mancozeb, combined or not, and the effects on disease control and soybean yield, cv. 'BMX Lança'. The work was conducted in the field in the 2016/17 and 2017/18 crops, in a randomized complete block design, with four replications. The following treatments were evaluated: T+P) trifloxystrobin + prothioconazole; A+B) azoxystrobin + benzovindiflupyr; T+P+MB) trifloxystrobin + prothioconazole + mancozeb; A+B+MB) azoxystrobin + benzovindiflupyr + mancozeb; MB) mancozeb; and Control (without fungicide application). After the occurrence of the first symptoms of the disease, the severity (%) was evaluated in five trifolia per plot, every seven days, making it possible to calculate the area under the disease progress curve (AUDPC). The yield components and productivity (kg ha-1) were also evaluated. In both crops, the combination of systemic fungicides and mancozeb reduced the severity (%) and progress of Asian rust, reaching a control above 81%. Treatment with trifloxystrobin + prothioconazole + mancozeb (T+P+MB) obtained the highest percentages of control (94.5% -2016/17,and 93.7% -2017/18) of Asian rust, and provided, in the 2016/17 crop, productivity at 15 sc ha-1, in relation to the fungicide applied alone (T+P). The combination of systemic fungicides and mancozeb, as proposed in this work, reduces the severity and progress of Asian rust and ensures the maintenance of the productive potential of the soybean.

A ferrugem asiática da soja é uma doença agressiva e o controle químico deve ser manejado assertivamente, para minimizar danos sobre a produtividade. Objetivou-se avaliar fungicidas sistêmicos e o multissítio mancozeb, combinados ou não, e os efeitos sobre o controle da doença e a produtividade da soja, cv. ‘BMX Lança’. O trabalho foi conduzido à campo nas safras 2016/17 e 2017/18, em delineamento de blocos ao acaso, com quatro repetições. Foram avaliados os tratamentos: T+P) trifloxistrobina + protioconazol; A+B) azoxistrobina + benzovindiflupyr; T+P+MB) trifloxistrobina + protioconazol + mancozeb; A+B+MB) azoxistrobina + benzovindiflupyr + mancozebe; MB) mancozeb; e Testemunha (sem aplicação de fungicidas). Após o surgimento dos primeiros sintomas da doença, a severidade (%) foi avaliada em cinco trifólios por parcela, a cada sete dias, possibilitando o cálculo da área abaixo da curva de progresso da doença (AACPD). Avaliou-se também os componentes de rendimento e a produtividade (kg ha-1). Em ambas as safras, a combinação entre fungicidas sistêmicos e o mancozeb reduziu a severidade (%) e o progresso de ferrugem asiática, atingindo um controle acima de 81%. O tratamento com trifloxistrobina + protioconazol + mancozeb (T+P+MB) obteve os maiores percentuais de controle (94,5% -2016/17; e 93,7% -2017/18) da ferrugem asiática, e proporcionou, na safra 2016/17, produtividade superior em 15 sc ha-1, em relação ao fungicida aplicado isoladamente (T+P). A combinação entre fungicidas sistêmicos e mancozeb, conforme proposto nesse trabalho, reduz a severidade e o progresso da ferrugem asiática e assegura a manutenção do potencial produtivo da soja.

Assuntos

RESUMO

Asian soybean rust is an aggressive disease and chemical control must be handled assertively to minimize productivity damage. The objective was to evaluate systemic fungicides and multisite mancozeb, combined or not, and the effects on disease control and soybean yield, cv. 'BMX Lança'. The work was conducted in the field in the 2016/17 and 2017/18 crops, in a randomized complete block design, with four replications. The following treatments were evaluated: T+P) trifloxystrobin + prothioconazole; A+B) azoxystrobin + benzovindiflupyr; T+P+MB) trifloxystrobin + prothioconazole + mancozeb; A+B+MB) azoxystrobin + benzovindiflupyr + mancozeb; MB) mancozeb; and Control (without fungicide application). After the occurrence of the first symptoms of the disease, the severity (%) was evaluated in five trifolia per plot, every seven days, making it possible to calculate the area under the disease progress curve (AUDPC). The yield components and productivity (kg ha-1) were also evaluated. In both crops, the combination of systemic fungicides and mancozeb reduced the severity (%) and progress of Asian rust, reaching a control above 81%. Treatment with trifloxystrobin + prothioconazole + mancozeb (T+P+MB) obtained the highest percentages of control (94.5% -2016/17,and 93.7% -2017/18) of Asian rust, and provided, in the 2016/17 crop, productivity at 15 sc ha-1, in relation to the fungicide applied alone (T+P). The combination of systemic fungicides and mancozeb, as proposed in this work, reduces the severity and progress of Asian rust and ensures the maintenance of the productive potential of the soybean.(AU)

A ferrugem asiática da soja é uma doença agressiva e o controle químico deve ser manejado assertivamente, para minimizar danos sobre a produtividade. Objetivou-se avaliar fungicidas sistêmicos e o multissítio mancozeb, combinados ou não, e os efeitos sobre o controle da doença e a produtividade da soja, cv. ‘BMX Lança. O trabalho foi conduzido à campo nas safras 2016/17 e 2017/18, em delineamento de blocos ao acaso, com quatro repetições. Foram avaliados os tratamentos: T+P) trifloxistrobina + protioconazol; A+B) azoxistrobina + benzovindiflupyr; T+P+MB) trifloxistrobina + protioconazol + mancozeb; A+B+MB) azoxistrobina + benzovindiflupyr + mancozebe; MB) mancozeb; e Testemunha (sem aplicação de fungicidas). Após o surgimento dos primeiros sintomas da doença, a severidade (%) foi avaliada em cinco trifólios por parcela, a cada sete dias, possibilitando o cálculo da área abaixo da curva de progresso da doença (AACPD). Avaliou-se também os componentes de rendimento e a produtividade (kg ha-1). Em ambas as safras, a combinação entre fungicidas sistêmicos e o mancozeb reduziu a severidade (%) e o progresso de ferrugem asiática, atingindo um controle acima de 81%. O tratamento com trifloxistrobina + protioconazol + mancozeb (T+P+MB) obteve os maiores percentuais de controle (94,5% -2016/17; e 93,7% -2017/18) da ferrugem asiática, e proporcionou, na safra 2016/17, produtividade superior em 15 sc ha-1, em relação ao fungicida aplicado isoladamente (T+P). A combinação entre fungicidas sistêmicos e mancozeb, conforme proposto nesse trabalho, reduz a severidade e o progresso da ferrugem asiática e assegura a manutenção do potencial produtivo da soja.(AU)

Assuntos

RESUMO

Objetivou-se estudar os efeitos da aplicação de glifosato e manganês (Mn) em estádios de desenvolvimento na nutrição e características agronômicas da cultura da soja, no município de Selvíria-MS, Brasil, na safra 2012/13, utilizando-se a variedade de soja BRS Valiosa RR em um Latossolo Vermelho Distrófico, de textura argilosa. O delineamento experimental foi em blocos casualizados com quatro repetições, distribuídos em esquema fatorial 6x2, sendo: seis doses de aplicação de glifosato (a-0g i.a. ha-1, b-aplicação de 720 g i.a. ha-1no estádio V3, c-1440 g i.a. ha-1 totalmente em V3, d- aplicação de 1440g i.a. ha-1 parcelado em duas aplicações de 720+720g i.a. ha-1 em V3 e V7, e -1440 g i.a. ha-1 totalmente em V7, e f -aplicação de 2160g i.a. ha-1 parcelado em duas aplicações de 720+1440 g i.a. ha-1 em V3e V7; com ou sem aplicação de Mn (0g ha-1e350g ha-1), no estádio V5. A aplicação foliar de Mn e de glifosato não influenciou as concentrações dos macro e micronutrientes foliar da cultura da soja. O glifosato nas doses de 720+1440 g i.a. ha-1, aplicado nos estádios V3 e V7, associado a adubação foliar com 350 g ha-1 de Mn no estádio V5, reduz a altura de inserção da primeira vagem, porém aumenta o número de grão por vagem. A produtividade de grãos de soja foi reduzida com a aplicação de glifosato na dose de 720+1440 g i.a. ha-1, nos estádios V3 e V7, independentemente da aplicação foliar com Mn.

The objective of this study was to evaluate the effects of glyphosate and manganese (Mn) application at developmental stages in the nutrition and agronomic characteristics of soybean crop, in the municipality of Selvíria-MS, Brazil, in the 2012/13 harvest, using the soybean variety BRS Valiosa RR in an Oxisol, with a clayey texture. The experimental design was a randomized block with four replications in a 6x2 factorial scheme, being: Six glyphosate application rates (0 g a.i. ha-1, application of 720 g a.i. ha-1in V3 stage, 1440 g a.i. ha-1V3, 720+720 g a.i. ha-1V3 and V7, 1440 g a.i. ha-1in V7, and application of 720+1440 g a.i. ha-1V3 and V7; with or without tMn application ( 0 g ha-1and 350 g ha-1) in V5 stage. Foliar applications of Mn and glyphosate did not influenced the leaf concentrations of macro and micronutrients in soybean. Glyphosate at doses of 720+1440 g a.i. ha-1, applied in stages V3 and V7, associated with foliar fertilization with 350 g ha-1 Mn in the V5 stage, reduces the first pod height, but increases the number grain per pod. Soybean yield was reduced with glyphosate application at a dose of 720+1440 g ai ha-1in V3 and V7 stages, regardless of Mn leaf application.

RESUMO

Objetivou-se estudar os efeitos da aplicação de glifosato e manganês (Mn) em estádios de desenvolvimento na nutrição e características agronômicas da cultura da soja, no município de Selvíria-MS, Brasil, na safra 2012/13, utilizando-se a variedade de soja BRS Valiosa RR em um Latossolo Vermelho Distrófico, de textura argilosa. O delineamento experimental foi em blocos casualizados com quatro repetições, distribuídos em esquema fatorial 6x2, sendo: seis doses de aplicação de glifosato (a-0g i.a. ha-1, b-aplicação de 720 g i.a. ha-1no estádio V3, c-1440 g i.a. ha-1 totalmente em V3, d- aplicação de 1440g i.a. ha-1 parcelado em duas aplicações de 720+720g i.a. ha-1 em V3 e V7, e -1440 g i.a. ha-1 totalmente em V7, e f -aplicação de 2160g i.a. ha-1 parcelado em duas aplicações de 720+1440 g i.a. ha-1 em V3e V7; com ou sem aplicação de Mn (0g ha-1e350g ha-1), no estádio V5. A aplicação foliar de Mn e de glifosato não influenciou as concentrações dos macro e micronutrientes foliar da cultura da soja. O glifosato nas doses de 720+1440 g i.a. ha-1, aplicado nos estádios V3 e V7, associado a adubação foliar com 350 g ha-1 de Mn no estádio V5, reduz a altura de inserção da primeira vagem, porém aumenta o número de grão por vagem. A produtividade de grãos de soja foi reduzida com a aplicação de glifosato na dose de 720+1440 g i.a. ha-1, nos estádios V3 e V7, independentemente da aplicação foliar com Mn.(AU)

The objective of this study was to evaluate the effects of glyphosate and manganese (Mn) application at developmental stages in the nutrition and agronomic characteristics of soybean crop, in the municipality of Selvíria-MS, Brazil, in the 2012/13 harvest, using the soybean variety BRS Valiosa RR in an Oxisol, with a clayey texture. The experimental design was a randomized block with four replications in a 6x2 factorial scheme, being: Six glyphosate application rates (0 g a.i. ha-1, application of 720 g a.i. ha-1in V3 stage, 1440 g a.i. ha-1V3, 720+720 g a.i. ha-1V3 and V7, 1440 g a.i. ha-1in V7, and application of 720+1440 g a.i. ha-1V3 and V7; with or without tMn application ( 0 g ha-1and 350 g ha-1) in V5 stage. Foliar applications of Mn and glyphosate did not influenced the leaf concentrations of macro and micronutrients in soybean. Glyphosate at doses of 720+1440 g a.i. ha-1, applied in stages V3 and V7, associated with foliar fertilization with 350 g ha-1 Mn in the V5 stage, reduces the first pod height, but increases the number grain per pod. Soybean yield was reduced with glyphosate application at a dose of 720+1440 g ai ha-1in V3 and V7 stages, regardless of Mn leaf application.(AU)

RESUMO

ABSTRACT Plant Growth Promoting Rhizobacteria (PGPR) have different mechanisms of action in the development of plants, such as growth promotion, production of phytohormones and antibiotic substances and changes in root exudates. These help to control plant diseases. In order to evaluate the potential of microorganisms in the control of Meloidogyne javanica and Ditylenchus spp., five rhizobacteria isolated from rhizosphere of garlic cultivated in the Curitibanos (SC) region were tested. Hatching chambers were set on Petri dishes, in which were added 10 mL of bacterial suspension and 1 mL of M. javanica eggs suspension, at the rate of 4500, on the filter paper of each chamber. The same procedure was performed with 300 juvenile Ditylenchus spp. The experimental design was completely randomized, with four replications. The evaluations were performed every 72 h for nine days. The antagonized population of nematodes was determined in Peters counting chamber, determining the percentage hatching (for M. javanica) and motility (for Ditylenchus spp). Isolates CBSAL02 and CBSAL05 significantly reduced the hatching of M. javanica eggs (74% and 54.77%, respectively) and the motility of Ditylenchus spp. (55.19% and 53.53%, respectively) in vitro. Isolates were identified as belonging to the genera Pseudomonas (CBSAL05) and Bacillus (CBSAL02).

Assuntos

RESUMO

Plant Growth Promoting Rhizobacteria (PGPR) have different mechanisms of action in the development of plants, such as growth promotion, production of phytohormones and antibiotic substances and changes in root exudates. These help to control plant diseases. In order to evaluate the potential of microorganisms in the control of Meloidogyne javanica and Ditylenchus spp., five rhizobacteria isolated from rhizosphere of garlic cultivated in the Curitibanos (SC) region were tested. Hatching chambers were set on Petri dishes, in which were added 10 mL of bacterial suspension and 1 mL of M. javanica eggs suspension, at the rate of 4500, on the filter paper of each chamber. The same procedure was performed with 300 juvenile Ditylenchus spp. The experimental design was completely randomized, with four replications. The evaluations were performed every 72 h for nine days. The antagonized population of nematodes was determined in Peters counting chamber, determining the percentage hatching (for M. javanica) and motility (for Ditylenchus spp). Isolates CBSAL02 and CBSAL05 significantly reduced the hatching of M. javanica eggs (74% and 54.77%, respectively) and the motility of Ditylenchus spp. (55.19% and 53.53%, respectively) in vitro. Isolates were identified as belonging to the genera Pseudomonas (CBSAL05) and Bacillus (CBSAL02).(AU)

Assuntos

RESUMO

Plant Growth Promoting Rhizobacteria (PGPR) have different mechanisms of action in the development of plants, such as growth promotion, production of phytohormones and antibiotic substances and changes in root exudates. These help to control plant diseases. In order to evaluate the potential of microorganisms in the control of Meloidogyne javanica and Ditylenchus spp., five rhizobacteria isolated from rhizosphere of garlic cultivated in the Curitibanos (SC) region were tested. Hatching chambers were set on Petri dishes, in which were added 10mL of bacterial suspension and 1mL of M. javanica eggs suspension, at the rate of 4500, on the filter paper of each chamber. The same procedure was performed with 300 juvenile Ditylenchus spp. The experimental design was completely randomized, with four replications. The evaluations were performed every 72h for nine days. The antagonized population of nematodes was determined in Peters counting chamber, determining the percentage hatching (for M. javanica) and motility (for Ditylenchus spp). Isolates CBSAL02 and CBSAL05 significantly reduced the hatching of M. javanica eggs (74% and 54.77%, respectively) and the motility of Ditylenchus spp. (55.19% and 53.53%, respectively) in vitro. Isolates were identified as belonging to the genera Pseudomonas (CBSAL05) and Bacillus (CBSAL02).

Assuntos

RESUMO

Phosphorus (P) intake, genotype, and growth environment in soybean cultivation can affect the composition of the soybean. This experiment was conducted in two locations (microregions I and II) using a randomized complete block design, including conventional soybean (BRS Sambaíba) and genetically modified (GM) [Msoy 9144 Roundup Ready (RR)] cultivars and varying doses of phosphorus fertilizer (0, 60, 120, and 240 kg/ha P2O5). Soybeans were evaluated for chemical composition, total phenols, phytic acid content, individual isoflavone content, antioxidant activity, oil quality, fatty acid profile, total carotenoid content, and individual tocopherol contents. Multivariate analysis facilitated reduction in the number of variables with respect to soybean genotype (conventional BRS Sambaíba and GM Msoy 9144 RR), dose of P2O5 fertilizer, and place of cultivation (microregion I and II). BRS Sambaíba had higher concentrations of ß-glucosides, malonylglucosides, glycitein, and genistein than Msoy 9144 RR, which showed a higher concentration of daidzein. The highest concentrations of isoflavones and fatty acids were observed in soybeans treated with 120 and 240 kg/ha P2O5, regardless of the location and cultivar.

Assuntos

RESUMO

This study aimed to characterize the harvest phenological stages of soybean cultivars intended for silage. Cultivars were evaluated for dry weight of the composite sample, branches, leaves and pods; wet mass of branches, leaves, pods and ground natural matter. This experiment was a 3 x 2 factorial randomized block design, with four replications each, where the first factor corresponds to the harvest stage: R4, R5 and R6; and the second factor refers to two soybean maturity groups (8.0 and 8.1). A significant interaction was detected only for ground natural matter. Higher values of most traits evaluated were observed for the R6 harvest phenological stage. The cultivar with maturity group 8.0 showed higher values for ground natural matter.

Objetivou-se com esse estudo caracterizar os estádios fenológicos de colheita de cultivares de soja destinada à ensilagem. As características avaliadas foram massa seca da amostra composta, das ramificações, das folhas e das vagens; massa úmida das ramificações, folhas, vagens e matéria natural triturada. O delineamento adotado foi o de blocos casualizados em um esquema fatorial 3 x 2, com quatro repetições cada, em que o primeiro fator corresponde ao estádio de colheita: R4, R5 e R6; e o segundo fator diz respeito aos dois cultivares de soja com grupos de maturações diferentes (8.0 e 8.1). A significância da interação foi constatada apenas na matéria natural triturada. Verificaram-se maiores valores para o estádio fenológico de colheita R6 na maioria dos caracteres avaliados. Observou-se que o cultivar com grupo de maturação 8.0 apresentou maiores valores na matéria natural triturada.

Assuntos

RESUMO

This study aimed to characterize the harvest phenological stages of soybean cultivars intended for silage. Cultivars were evaluated for dry weight of the composite sample, branches, leaves and pods; wet mass of branches, leaves, pods and ground natural matter. This experiment was a 3 x 2 factorial randomized block design, with four replications each, where the first factor corresponds to the harvest stage: R4, R5 and R6; and the second factor refers to two soybean maturity groups (8.0 and 8.1). A significant interaction was detected only for ground natural matter. Higher values of most traits evaluated were observed for the R6 harvest phenological stage. The cultivar with maturity group 8.0 showed higher values for ground natural matter.(AU)

Objetivou-se com esse estudo caracterizar os estádios fenológicos de colheita de cultivares de soja destinada à ensilagem. As características avaliadas foram massa seca da amostra composta, das ramificações, das folhas e das vagens; massa úmida das ramificações, folhas, vagens e matéria natural triturada. O delineamento adotado foi o de blocos casualizados em um esquema fatorial 3 x 2, com quatro repetições cada, em que o primeiro fator corresponde ao estádio de colheita: R4, R5 e R6; e o segundo fator diz respeito aos dois cultivares de soja com grupos de maturações diferentes (8.0 e 8.1). A significância da interação foi constatada apenas na matéria natural triturada. Verificaram-se maiores valores para o estádio fenológico de colheita R6 na maioria dos caracteres avaliados. Observou-se que o cultivar com grupo de maturação 8.0 apresentou maiores valores na matéria natural triturada.(AU)

Assuntos

RESUMO

A cada ano são descobertos e utilizados novos produtos para o tratamento de sementesna cultura da soja (Glycine maxL. Merril), visando aumentos de produção. Há a necessidade de conhecer a influência desses produtos sobre o desenvolvimento das plantas, a fim de obter sucesso na atividade. O objetivo do experimento foi avaliar o efeito de principais produtos aplicados via tratamento de sementes, sobre a morfologia de plantas de soja, em diferentes fases de desenvolvimento da cultura, bem como, sobre os componentes do rendimento e produtividade. Os produtos utilizados foram: tiametoxan; [abamectina+tiametoxan + fludioxonil]; [fipronil + tiofanatometilico + piraclostrobina]; [imidacloprido + tiodicarbe]; CruiserAdvanced(r); carboxamida; abamectina; [metalaxyl-M + fludioxonil]; além da testemunha sem tratamento. Na primeira etapa, avaliou-se a qualidade fisiológica das sementes tratadas. Posteriormente, avaliou-se o crescimento inicial aos 15, 30 e 45dias após a emergência. Na terceira etapa, avaliaram-se características agronômicas e componentes de rendimento. O delineamento experimental utilizado para os testes fisiológicos das sementes foi inteiramente casualizado e para as determinações de desenvolvimento inicial e de final de ciclo, blocos ao acaso. Para análise estatística, utilizou-se o programa SASM-Agri. Concluiu-se que a mistura de ingredientes ativos inseticidas e fungicidas prejudica o desenvolvimento inicial das plântulas de soja. Aos 45 dias após a emergência, há efeito positivo dos produtos tiametoxan, [abamectina + tiametoxan + fludioxonil], CruiserAdvanced(r) e [metalaxyl-M + fludioxonil] sobre o crescimento, porém este estímulo não se reflete na produção final.

Every year, new products are discovered and used for seed treatment in soybeans (Glycine max.L. Merril), aiming to increase production. There is the need to know the influence of the products on the development of plants in order to be succeed in the activity. The aim of the experiment was to evaluate the effect of products applied as seed treatment on the morphology of soybean plants at different stages of crop development, as well as the components of income and productivity. The products used were: tiametoxan; [abamectina + tiametoxan + fludioxonil]; [fipronil + tiofanatometilico + piraclostrobina]; [imidacloprido + tiodicarbe]; Cruiser Advanced(r); carboxamida; abamectina; [metalaxyl-M + fludioxonil]; and the control without treatment. In the first step, it was evaluated the physiological quality of treated seed. Subsequently, it was evaluated the initial growth at 15, 30 and 45 days after emergence. In the third stage were evaluated agronomic traits and yield components. The experimental design used for physiological tests of the seeds was randomized and the measurements of early development and late season, were randomized blocks. For statistical analysis, it was used the program SASM-Agri (CANTERI et al., 2001). It was concluded that the mixture of active ingredients insecticides and fungicides affect the early development of soybean seedlings. At 45 days after emergence, there is a positive effect of the products Tiametoxan, [abamectina + tiametoxan + fludioxonil], Cruiser Advanced(r) and [metalaxyl-M + fludioxonil] on growth, but this stimulus, is not reflected in the final production.

RESUMO

A utilização de sementes de qualidade, a equilibrada nutrição das plantas e a adoção de técnicas adequadas de cultivo são fundamentais para o sucesso da lavoura. O uso de silício (Si) é uma tecnologia limpa do ponto de vista ambiental, que pode conferir vários benefícios para as plantas como estimular o crescimento e a produção vegetal, proporcionar maior tolerância das plantas ao ataque de insetos e doenças, reduzira transpiração e aumentar a taxa fotossintética e, proteger contra estresses abióticos. O objetivo do trabalho foi avaliar o efeito da aplicação de Si oriundo da cinza de casca de arroz carbonizada, via solo, nas características agronômicas, na produtividade e na qualidade fisiológica das sementes de cultivares de soja. O experimento foi conduzido em vasos de 18 L preenchidos com solo, sob o delineamento experimental de blocos casualizados, com quatro repetições. As cultivares de soja utilizadas foram BMX Turbo RR e NA 5909 RR, cultivadas sob cinco doses de silício via solo (0, 1, 2, 3, e 4 t ha-1). Foram avaliadas as características agronômicas e o rendimento de sementes (número total de legumes nos ramos, número total de sementes nos ramos, número total de legumes na haste principal, número total de sementes na haste principal, número total de legumes por planta, número total de sementes por planta, massa de sementes por planta e massa de 1000 sementes). A qualidade fisiológica das sementes foi avaliada pelos testes de germinação e de vigor (primeira contagem da germinação, teste de frio, envelhecimento acelerado, comprimento da parte aérea e da raiz). A aplicação de silício via solo é benéfico para a cultura da soja, melhorando as principais características agronômicas (número total de legumes nos ramos, número total de sementes nos ramos, número total de legumes por planta, massa de sementes por planta) e aumentando o rendimento de sementes por planta na cultivar de soja BMX Turbo RR.[...](AU)

Use of quality seeds, balanced plant nutrition and the adoption of adequate cultivation techniques are critical to the success of the soybean crop. Use of silicon (Si) is a clean technology from an environmental point of view, which can confer several benefits to the plants as stimulate growth and plant production, improve tolerance of plants to attack by insects and diseases, reduce perspiration and increase the photosynthetic rate and protect against abiotic stresses. The goal was to evaluate the effect of soil Si application derived from rice husk ash on the agronomic characteristics, productivity and physiological quality of soybean cultivars seeds. The experiment was conducted in pots of 18 L filled with soil, under a randomized block design with four replications. The soybean cultivars were BMX Turbo RR and NA 5909 RR, grown under five doses of silicon (0, 1, 2, 3, and 4 t ha-1). Agronomic traits and seed yield were evaluated (total number of pods on branches, total number of seeds on the branches, the total number of pods on the main stem, total number of seeds on the main stem, total number of pods per plant, total number of seeds per plant, seed weight per plant and seed weight of 1000). Physiological seed quality was evaluated by germination and vigor tests (first count of germination, cold test, accelerated aging, shoot length and root). The soil application of silicon is beneficial for the soybean crop, improving the main agronomic characteristics (total number of pods on branches, total number of seeds in the branches, total number of pods per plant, weight of seeds per plant) and increasing seed yield per plant in soybean cultivar BMX Turbo RR. The mass of a thousand seeds is positively influenced by the dose of 1.67 t ha-1 for the cultivar BMX Turbo RR and up to a dose of 2.32 t ha-1 for the cultivar NA 5909 RR. Cultivar BMX Turbo RR seed vigor is increased with the use of silicon in the soil.(AU)

Assuntos

RESUMO

A semente de soja apresenta, cerca de 20% da sua massa seca em óleo e 40% em proteína. Esse teor de óleo pode sofrer influência perante as condições ambientais durante o enchimento das sementes, produzindo modificações na sua composição bioquímica. Em condições de cultivo in vivo é difícil controlar esse fator. Nesse sentido, o cultivo in vitro vem auxiliar a pesquisa, pois a semente fica isolada da planta mãe em ambiente controlado. O objetivo deste trabalho foi avaliar os teores de óleo das cultivares BRS 184 e BRS 282 cultivadas in vitro e in vivo. O cultivo in vivo ocorreu em casa de vegetação em vasos com a coleta de sementes no estádio R8, e o cultivo in vitro, em laboratório, utilizando sementes imaturas removidas da planta mãe no estádio R5 e cultivadas em meio de cultura líquido contendo 20 mM, 40 mM e 60 mM de glutamina, e concentração de sacarose de 204,5 mM, com agitação constante por oito dias à temperatura de 25 ± 0,2 ºC. Decorrido o tempo para o cultivo in vitro foi avaliado o ganho de massa de matéria fresca das sementes, e após, em ambos os experimentos, foi determinado o teor de óleo para o cultivo em R5, e para R8. O acúmulo de óleo nas sementes de soja apresenta interações complexas, variando entre genótipo e condições ambientais tanto no cultivo in vivo quanto in vitro. Há correlação positiva entre ganho de massa e teor de óleo nas sementes.(AU)

The soybean seed presents around 20% of oil and 40% of protein. These levels, during the filling of the seeds, can be influenced by environmental conditions, where are produced changes on its biochemistry composition. The higher temperatures promote the accumulation of protein, and the moderate temperatures favor the oil accumulation. Under in vivo growing conditions the control of these factors is difficult. The in vitro procedure can help the research, because the seed can be isolated from the mother plant in controlled environment. The objective of this experiment was to evaluate the oil content of BRS184 and BRS282in vitro and in vivo. The in vivo procedure, occurred in the greenhouse, with 3plantsper potand seed collectionin R8, and in vitro procedure, developed in the laboratory, where the immature seeds were taken from the mother plant in R5 stage, cultured with a liquid culture medium containing 20 mM, 40 mM and 60 mM glutamine, with a constant agitation, during eight days at 25 ± 0.2 C, and sucrose concentration of 204.5 mM. After the in vitro cultivation time for, the fresh weight gain of the seeds was evaluated, and after both experiments, was determined by the oil content for cultivation in R5, and R8. The accumulation of oil in soybean seeds presents a complex interaction, ranging between the genotype and the environmental conditions, under in vivo and in vitro cultivation. There is a positive correlation between production and oil content in seeds.(AU)

Assuntos

RESUMO

A cada ano são descobertos e utilizados novos produtos para o tratamento de sementesna cultura da soja (Glycine max L. Merril), visando aumentos de produção. Há a necessidade de conhecer a influência desses produtos sobre o desenvolvimento das plantas, a fim de obter sucesso na atividade. O objetivo do experimento foi avaliar o efeito de principais produtos aplicados via tratamento de sementes, sobre a morfologia de plantas de soja, em diferentes fases de desenvolvimento da cultura, bem como, sobre os componentes do rendimento e produtividade. Os produtos utilizados foram: tiametoxan; [abamectina+tiametoxan + fludioxonil]; [fipronil + tiofanatometilico + piraclostrobina]; [imidacloprido + tiodicarbe]; CruiserAdvanced(r); carboxamida; abamectina; [metalaxyl-M + fludioxonil]; além da testemunha sem tratamento. Na primeira etapa, avaliou-se a qualidade fisiológica das sementes tratadas. Posteriormente, avaliou-se o crescimento inicial aos 15, 30 e 45dias após a emergência. Na terceira etapa, avaliaram-se características agronômicas e componentes de rendimento. O delineamento experimental utilizado para os testes fisiológicos das sementes foi inteiramente casualizado e para as determinações de desenvolvimento inicial e de final de ciclo, blocos ao acaso. Para análise estatística, utilizou-se o programa SASM-Agri. Concluiu-se que a mistura de ingredientes ativos inseticidas e fungicidas prejudica o desenvolvimento inicial das plântulas de soja. Aos 45 dias após a emergência, há efeito positivo dos produtos tiametoxan, [abamectina + tiametoxan + fludioxonil], CruiserAdvanced(r) e [metalaxyl-M + fludioxonil] sobre o crescimento, porém este estímulo não se reflete na produção final.(AU)

Every year, new products are discovered and used for seed treatment in soybeans (Glycine max. L. Merril), aiming to increase production. There is the need to know the influence of the products on the development of plants in order to be succeed in the activity. The aim of the experiment was to evaluate the effect of products applied as seed treatment on the morphology of soybean plants at different stages of crop development, as well as the components of income and productivity. The products used were: tiametoxan; [abamectina + tiametoxan + fludioxonil]; [fipronil + tiofanatometilico + piraclostrobina]; [imidacloprido + tiodicarbe]; Cruiser Advanced(r); carboxamida; abamectina; [metalaxyl-M + fludioxonil]; and the control without treatment. In the first step, it was evaluated the physiological quality of treated seed. Subsequently, it was evaluated the initial growth at 15, 30 and 45 days after emergence. In the third stage were evaluated agronomic traits and yield components. The experimental design used for physiological tests of the seeds was randomized and the measurements of early development and late season, were randomized blocks. For statistical analysis, it was used the program SASM-Agri (CANTERI et al., 2001). It was concluded that the mixture of active ingredients insecticides and fungicides affect the early development of soybean seedlings. At 45 days after emergence, there is a positive effect of the products Tiametoxan, [abamectina + tiametoxan + fludioxonil], Cruiser Advanced(r) and [metalaxyl-M + fludioxonil] on growth, but this stimulus, is not reflected in the final production.(AU)

Assuntos

RESUMO

Arbuscular mycorrhizal fungi (AMF) are obligatory biotrophics, which complicates the feasibility of producing inoculants. Thus, the discovery of substances capable of stimulating mycorrhizal colonization, like the isoflavone formononetin emerges as a promising alternative to explore the benefits of AMF native soil in extensive crops system. The aim of this study was evaluate the application of the isoflavone formononetin (7-hydroxy-4'-methoxy isoflavone) andfungicide via seed in Cerrado soil in no-tillage system and fertilization with two doses of phosphorus in soybean under field and controlled conditions. In the field experiment the treatments were three levels of formononetin (0, 0.5 and 1.0 mg Formononetin seed-1) in the absence and presence of fungicide (Carbendazim + Thiram commercial mix) applied to seeds with two doses of phosphorus (100 % and 33% of the recommended fertilization). The study was conducted until the maturation of soybeans. The greenhouse conditions experiment was implemented with the same treatments used in the field research and the flowering stage of the soybean plant was simulated water stress during 10 days, returning to normal irrigation until to harvest the soybean grain. Applying of formononetin stimulated the increased of mycorrhizal colonization, number of nodules, vegetative growth and soybean production in the greenhouse. In the field research the treatments contributed to attenuate the negative effect of the fungicide Carbendazim + Thiram in soybean reflecting increased soybean production and adequate supply of soil phosphorus besides high density of propagules of natives AMF that contributed to reduce the benefits of stimulating mycorrhizal (formononetin) in this research.

Os fungos micorrízicos arbusculares (FMAs) são biotróficos obrigatórios, o que dificulta a viabilidade da produção de inoculantes. Com a descoberta de substâncias capazes de estimular a colonização micorrízica, o isoflavonóide formononetina surge como uma alternativa promissora para explorar os benefícios dos FMAs nativos do solo em cultivos extensivos. O objetivo do presente estudo foi de avaliar os efeitos das aplicações do isoflavonóide formononetina (7-hydroxy-4'-methoxy isoflavone) e de fungicida nas sementes em solo do Cerrado no sistema de plantio direto com duas doses de fósforo na cultura da soja em campo e em casa de vegetação. No experimento de campo os tratamentos foram três doses de formononetina (0, 0,5 e 1,0 mg de Formononetina semente-1); na ausência e presença de fungicida (Mistura comercial Carbendazim + Thiram) aplicado via semente e duas doses de fósforo (100 % e 33 % da adubação recomendada). O experimento de casa de vegetação foi implantado com os mesmos tratamentos utilizado no estudo em campo e na fase de florescimento das plantas de soja foi simulado um estresse hídrico, por 10 dias, retornando a irrigação normal até a colheita dos grãos. A aplicação de formononetina estimulou aumento da colonização micorrízica, número de nódulos, crescimento vegetativo e a produção de grãos soja em condições de déficit hídrico simulado em casa de vegetação e no no estudo de campo contribui para amenizar o efeito negativo dos fungicidas nas plantas de soja refletindo em aumento da produção da soja.

Assuntos