Control of Conyza spp. with sequential application of glufosinate in soybean pre-sowing / Controle de Conyza spp. com aplicação sequencial de glufosinate em pré-semeadura da soja

ABSTRACT: Conyza spp. is among the main weeds reported worldwide. Due to its aggressiveness, such as high seed production and dispersion, and the growing reports of biotypes resistant to glyphosate, paraquat, and other herbicides, different control practices are required. Thus, this study aimed to evaluate the efficacy of herbicides with sequential application of glufosinate in soybean pre-sowing for control of Conyza spp. with indicative of resistant to paraquat. The study was carried out in the field, at Assis Chateaubriand and Palotina, state of Paraná, Brazil, in the 2018/19 season. The experiments were conducted in a randomized block design with four replications. The treatments consisted in application of glyphosate, 2,4-D, saflufenacil, glufosinate, saflufenacil/imazethapyr, diclosulam, paraquat/diuron, paraquat and imazethapyr/flumioxazin, at different combinations, in soybean pre-sowing. Control of Conyza spp., crop injury to soybean plants and variables related to agronomic performance (plant height and yield) were evaluated. All treatments were selective for soybean, which showed stronger crop injury in the presence of diclosulam herbicide, but this did not compromise soybean agronomic performance. In general, control levels were high for the treatments used. Except for paraquat treatments, in the area with the highest frequency of Conyza spp. with indicative of resistant to paraquat, and imazethapyr/flumioxazin treatment in both areas. These control results emphasized the importance of glufosinate in this management system and showed promising results for saflufenacil/imazethapyr.

RESUMO: A planta daninha Conyza spp. está entre as principais encontradas em todo o mundo. Devido a sua agressividade, como elevada produção e dispersão de sementes e os crescentes relatos de biótipos resistentes ao glyphosate, paraquat e outros herbicidas, faz-se necessário o uso de diferentes ferramentas de manejo. Assim, o objetivo deste estudo foi avaliar a eficácia de herbicidas com aplicação sequencial de glufosinate em pré-semeadura da soja, no controle de Conyza spp. com indicativo de resistência ao paraquat. O estudo foi realizado em campo nos municípios de Assis Chateaubriand e Palotina, estado do Paraná (PR), Brasil, na safra 2018/19. O delineamento experimental utilizado foi o de blocos casualizados, com quatro repetições. Os tratamentos foram compostos pela aplicação de glyphosate, 2,4-D, saflufenacil, glufosinate, saflufenacil/imazethapyr, diclosulam, paraquat/diuron, paraquat e imazethapyr/flumioxazin, em diferentes combinações em pré-semeadura da soja. Foram avaliados controle de Conyza spp., sintomas de injúria nas plantas de soja e variáveis relacionadas ao desempenho agronômico (altura de plantas e produtividade). Todos os tratamentos mostraram-se seletivos a soja. Visualizou-se maiores sintomas de injúria quando se tinha a presença do herbicida diclosulam, mas não resultou em danos ao desempenho agronômico da soja. De forma geral os níveis de controle foram altos para os tratamentos utilizados, em exceção para os tratamentos com paraquat na área que apresentava maior frequência de Conyza spp. com indicativo de resistência a este herbicida, e para o tratamento com imazethapyr/flumioxazin nas duas áreas. Estes resultados de controle enfatizam a importância do glufosinate neste sistema de manejo e demostram resultados promissores para saflufenacil/imazethapyr.

Performance of Soybean Seedlings Upon Nutrient Application by Seed Coating

ABSTRACT The aim of this study was to evaluate the effect of different seed coatings consisting of various combinations of three nutrients (calcium, magnesium and silicon) on two soybean cultivars (BRS 243 RR and CD 233 RR). Dolomitic limestone and aluminum silicate were chosen as the nutrient sources. Leaf area, plant height, shoots dry matter, crop growth rate, relative growth rate and net assimilation rate were the studied variables, evincing that the seed coating that comprised calcium, magnesium and silicon led to better performance in terms of growth rates 30 days after emergence. Significant differences in the response to the seed coatings were also observed between the two studied soybean genotypes.

Energy flows in lowland soybean production system in Brazil / Fluxos de energia em sistema de produção de soja em várzea no Brasil

ABSTRACT: Soybean is the main product of Brazilian agribusiness, both production and income. Considering the increase in food and energy demand and the search for more sustainable production systems, this study aimed to analyze inputs and energy use of a possible area of expansion of soybean production: a system under sub irrigation management located in a lowland area of Cerrado biome, northern region of Brazil. Its environmental performance was compared to other Brazilian locations among them traditionally soybean producers. The evaluation and comparison was made through material and energy flow tools in order to determine the inputs embodied per area, as well as energy demand, availability and efficiency in the analyzed production system. Energy demand (IE) and energy availability (OE) of the analyzed production system were 7.6 and 57.1 GJ ha-1, respectively. Energy balance (EB) was 49,5 GJ ha-1, energy return over investment (EROI) was 7.5 and embodied energy in grains (EE) was 2,2 MJ kg-1, respectively. Highest energy consumption was due to the use of fertilizers, fuel and herbicide. The system is energy efficient, since it provides more energy than demands, and efficient when compared to usual production systems in other regions, however it is highly dependent on non-renewable energy.

RESUMO: A soja é o principal produto do agronegócio Brasileiro, em volume e geração de renda. Considerando o aumento da demanda por alimentos e energia, bem como a busca por sistemas de produção mais sustentáveis, o presente estudo teve como objetivo analisar o uso de energia oriunda de insumos agrícolas em área de possível expansão de produção de soja: sistema de produção sob subirrigação em área de várzea no Cerrado, região Norte do Brasil. Seu desempenho ambiental foi comparado a outros locais no Brasil, entre os quais regiões tradicionalmente produtores de soja. A avaliação e comparação foram feitas por meio do uso de ferramentas de fluxo de materiais e energia, a fim de determinar a quantidade de insumos utilizados por área, bem como a demanda, disponibilidade e eficiência do uso de energia no sistema de produção avaliado. A demanda (IE) e disponibilidade (OE) de energia foram de 7.6 e 57.1 GJ ha-1, respectivamente. O balanço energético (BE), o retorno de energia sobre o investimento (EROI) e a energia incorporada dos grãos (EE) foram 49.5 GJ ha-1, 7.5 e 2.2 MJ kg-1, respectivamente. O maior consumo de energia foi devido à utilização de fertilizantes, herbicidas e combustível. O sistema analisado é eficiente no uso da energia, uma vez que fornece mais energia do que é demandado, e eficiente quando comparado a sistemas de produção usuais em outras regiões, embora seja altamente dependente de energia de origem não-renovável.

Enteromorpha intestinalis Derived Seaweed Liquid Fertilizers as Prospective Biostimulant for Glycine max

ABSTRACT In the present study, the potential of seaweed liquid fertilizer (SLF) of marine algae Enteromorpha intestinalis was evaluated for its effect on seed germination, yield, biochemical parameters and pigment characteristics of Glycine maxE. intestinalis was collected form Mandapam coast of Gulf of Mannar, Tamil Nadu, and the dried seaweeds were used for the preparation of SLF. G. max seeds were germinated with four different concentrations (20, 40, 60, and 100%) of SLF; its growth and yield parameters were evaluated and compared with chemical fertilizer and control. The morphological and bio-chemical parameters such as seed germination (100%), root (6.6cm) and shoot length (5.4 cm), carbohydrates (0.098 mg/g), protein (0.56 mg/g), pigment (0.444 mg/g chl a; 1.073 mg/g chl b; 3.70 mg/g carotenoids) of the plant was found maximum at a concentration of 60% SLF. The phenol content (3.25 mg/g) was maximum in 40% SLF. The GC-MS analysis of SLF revealed the presence of notable benzoic compounds involved in plant growth promotion. Results showed thatE. intestinalis derived SLF was potential biostimulant forG. max. Thus, marine algae based fertilizer could be an effective and alternate to the chemical fertilizers emphasizing the need for systematic evaluation programme for SLF on various crops.

Chemical constituents from pods of Glycine max / 中草药

Objective: To investigate the chemical constituents from the pods of Glycine max. Methods: The chemical constituents were isolated by repeated silica gel chromatography, Sephadex LH-20 gel column chromatography, medium pressure column chromatography, and semi-preparative liquid chromatography. Their structures were elucidated by chemical properties and spectroscopic analyses. Results: Fourteen compounds were identified to be 4,4'-diphenylmethane-bis (ethyl) carbamates (1), 2,6-dimethoxy-1,4-benzoquinone (2), (+)-medioresinol (3), taraxerone (4), lupenone (5), 7,3',4'-trihydroxyflavone (6), coumestrol (7), indole-3-carboxylic acid (8), apigenin (9), phaseol (10), 7,4'-dihydroxyflavone (11), stigmasterol (12), β-sitosterol (13), and β-daucosterol (14). Conclusion: Compounds 1-5 are obtained from the pods of G. max for the first time, and compound 6 is obtained from this plant for the first time.

Analysis on amino acids in Sojae Semen Preparatrm and Glycine max by pre-column derivatization RP-HPLC / 中草药

Objective: To analyze the free and hydrolyzed amino acids in Sojae Semen Preparatum (SSP) and Glycine max (GM) by pre-column derivatization RP-HPLC. Methods: Free amino acids extracted in HCl (0.1 mol/L) by ultrasonic method and hydrolyzed amino acids extracted in HCl (6 mol/L) by hydrolysis method were both derivated by the agent phenylisothiocyanate so as to analyze them by gradient elution. Results: There were 16 kinds of amino acids in both SSP and GM. The 16 kinds of amino acids had good linearity in the range of 0.031-1.750 μmol/mL with the coefficients of correlation all over 0.9979. The average recoveries were 91.02%-102.04% and the RSD values were between 1.01% and 4.81%. Conclusion: The method is not only sensitive and accurate, but also has the high repeatability and stability, and the 16 kinds of amino acids could be separated in the case of the samples with more impurities. The common C18 column is widely used for the determination of many other samples riched in amino acids at lower cost.

Desempenho de cultivares transgênicas de soja em sucessão a culturas de inverno em semeadura direta / Performance of transgenic soybean cultivars in succession to winter cover crops under no tillage system

Objetivou-se com esse trabalho avaliar o desempenho de cultivares de soja transgênica em sucessão a culturas de inverno na implantação do sistema de semeadura direta. O delineamento experimental utilizado foi o de blocos casualizados, em esquema de parcelas subdivididas, com quatro repetições. As parcelas foram representadas por cinco espécies cultivadas no inverno, aveia branca, nabo forrageiro, cevada, trigo e ervilha forrageira e área de pousio. As subparcelas foram constituídas por seis cultivares de soja (BRS 243 RR, BRS 244 RR, BRS 245 RR, BRS 247 RR, BRS 255 RR e BRS 256 RR). Para as características agronômicas e os componentes de produção da cultura da soja indicou que a interação culturas de inverno x cultivares de soja foi significativa para a população final de plantas, número de nódulos por planta, massa de matéria seca de nódulos por planta, número de vagens por planta, número de grãos por vagem e produtividade de grãos. O tratamento de pousio proporcionou os menores valores de nodulação da cultura da soja. Para produtividade de grãos, houve diferenças entre as culturas de inverno antecessoras para o cultivar BRS 243 RR, sendo que, a aveia proporcionou maiores valores.

The objective of this research was to evaluate crop yield and some characteristics and yield components of transgenic soybean cultivars sown after different winter cover crops in the first year under no tillage system. The experimental design was the completely randomized block with split plots and four replications. The main plots consisted of five winter cover crops, white oat (Avena sativa L.), forage turnip (Raphanus sativus L.), barley (Hordeum vulgare L.), wheat (Triticum aestivum L.) and ground pea (Pisum sativum L.) and an area under fallow (spontaneous vegetation). The subplots consisted of six soybean cultivars (BRS 243 RR, BRS 245 RR, BRS 247 RR, BRS 255 RR, BRS 256 RR and BRS 244 RR). Variance analysis for agronomic characteristics showed that soybean yield components were influenced by the interaction between winter crop and soybean cultivar. Thus, final population, number of nodes and pods per plant, nodes dry matter per plant, number of grains per pod and grain yield were affected significantly. When soybean nodulation was evaluated, the treatment with the area under fallow showed lower values. There was difference among winter crops for BRS 243 RR grain yield, white oat showed the highest values.

Atributos físicos e desempenho agronômico da cultura da soja em um Latossolo Vermelho distroférrico submetido a dois sistemas de manejos / Physical attributes and performance of soybean in Oxisol under two management systems

Os sistemas de manejo agindo com condicionadores do solo podem alterar a qualidade física do solo e restringir ou maximizar a produção agrícola. Objetivou-se com este estudo avaliar os atributos físicos e o desempenho agronômico da cultura da soja em um Latossolo Vermelho distroférrico submetido a dois sistemas de manejos em Dourados-MS. O delineamento experimental foi em blocos casualizados, em esquema de parcelas subsubdivididas, sendo dois sistemas manejo do solo nas (parcelas) com 0 e 2000 kg ha-1 de gesso agrícola (subparcelas) e cinco profundidades (0-0,05, 0,05-0,10, 0,10-0,15, 0,15-0,20 e 0,20-0,30 m, sendo as subsubparcelas) com quatro repetições. Foram avaliados atributos físicos do solo e desempenho agronômico da cultura da soja. Os resultados mostram que a densidade do solo foi maior no plantio direto. A macroporosidade foi maior na profundidade de 0-0,05 m no plantio convencional e a microporosidade aumentou com a profundidade nos sistemas de manejo. A resistência à penetração aumentou em maiores profundidades. O plantio direto reduziu o número de vagens e o efeito residual de gesso aumentou a altura final das plantas.

Management systems acting with soil conditioners can change the physical quality of the soil and restrict or maximize agricultural production. In this study, we assessed the effect of the tillage system with and without the gypsum residual effect at different depths in a dystrophic red Oxisol in Dourados, State of Mato Grosso do Sul, Brazil. The experimental design was randomized blocks with arrangements of subdivided plots; the treatments were two soil manure systems, in plots and with 0 and 2000 kg ha-1 gypsum (subplots) and five depths (0-0.05, 0.05-0.10, 0.10-0.15, 0.15-0.20, and 0.20-0.30 m, the latter ones being the subplots) with four replicates. Physical attributes of the soil and agronomic performance of soybean crop were evaluated. The results show that the soil density was higher in tillage system and the gypsum residual effect influenced the soil density at 0.10-0.15 m deep. The macro porosity was higher at 0-0.05 m deep in conventional sowing and the micro porosity increased with the depth in the manure systems. The penetration resistance increased in higher depths. The tillage system with reduced pod number and gypsum residual effect increased the plant height.

Índice de cobertura vegetal e sua modelagem para cultivares de soja no sul de Minas Gerais / Index of vegetal cover and its modeling for soybean cultivars in the south of Minas Gerais

A cobertura vegetal do solo é decisiva para redução dos efeitos erosivos do impacto direto das gotas de chuva na superfície do solo. Desta forma, objetivou-se com este estudo determinar o índice de cobertura vegetal (CV) e desenvolver modelos para sua estimativa para a cultura da soja, usando os atributos climáticos no período de chuvas intensas no Sul de Minas Gerais. As determinações da CV foram feitas semanalmente, na área experimental do Departamento de Ciência do Solo, Universidade Federal de Lavras, no período de novembro de 1999 a maio de 2000, em 28 cultivares de soja com potencial para cultivo nesta região. Para avaliação da cobertura vegetal foi utilizada a metodologia descrita por Stocking (1988). Na modelagem procurou-se relacionar a CV com os valores acumulados dos seguintes atributos climáticos: temperatura média (Tmed), precipitação (PREC) e umidade relativa do ar (UR). Os valores de cobertura vegetal apresentaram uma amplitude de variação de 56 a 83 por cento, sendo BR 162, LO 12 L e M. Soy 108 as cultivares mais eficientes e FT Abyara e Tucano as menos eficientes. O hábito diferencial de crescimento das cultivares ajuda a explicar esse comportamento. O modelo ajustado adequado para estimativa da CV foi: CV = 116589,976 + 0,422 . Tmed + 0,132 . PREC - 0,095 . UR + 0,000024 . Tmed², R² = 0,99 (P < 0,01). A determinação da CV nas diferentes fases de desenvolvimento da cultura é de grande importância, uma vez que seu estabelecimento coincide com o período de maior potencial erosivo das chuvas na região estudada.

Vegetal cover of soil is decisive to reduce the erosive effects of direct impact of raindrops on the soil surface. Therefore, the objective of this study was to determine the vegetal cover (CC) index and to develop models to estimate it for soybean cultivars, using climatic attributes in the period of intense rains in the South of the State of Minas Gerais in Brazil. CC was measured weekly in the experimental area of the Department of Soil Science, Federal University of Lavras, from November 1999 to May 2000, for 28 soybean cultivars with yield potential in this region. To evaluate the vegetal cover, the method described by Stocking (1988) was used. In the modeling, CC was related with the accumulated values of following climatic attributes: medium temperature (Tmed), precipitation (PREC), and relative humidity of the air (RH). Vegetal cover values presented an amplitude from 56 to 83 percent, being BR 162, LO 12 L and M. Soy 108, the more efficient cultivars, and the FT Abyara and Tucano, the least efficient ones. The differential growth habit of the cultivars helps to explain this behavior. The best adjusted model for the estimative of CC was: CC = 116589.976 + 0.422, Tmed + 0.132, PREC - 0.095, RH + 0.000024 Tmed², R² = 0.99 (P < 0.01). The knowledge of CC for different development phases of the crop is of great importance, taking into account that its establishment time coincides with the highest erosive potential of the rains in the studied region.

Genetic diversity among Brazilian soybean cultivars based on SSR loci and pedigree data

In this study, simple sequence repeats (SSR) loci and pedigree data were used to investigate the genetic relationship in a group of 168 Brazilian soybean cultivars. Eighteen SSR loci produced an average of 5.06 alleles and a mean gene diversity of 0.58 for the cultivars studied. Genetic distance (GD) was determined using the modified Roger's Wright distance, and a final dendrogram was in agreement with the cultivar pedigree. A distance matrix based on the coefficient of parentage scores was also generated for the cultivars, which ranged from 0 to 1, with a mean of 0.18, whereas SSR-based genetic similarity (1- GD) ranged from 0.01 to 0.90, with a mean of 0.25. Mantel's Z test showed that the similarity matrices generated from both the data sets were low, but significantly correlated (r = 0.31, p<0.001). The results showed that SSR data and pedigree analyses could help to quantify more accurately the degree of relationship among the soybean cultivars.

Locos microssatélites e dados de genealogia foram utilizados para avaliar a diversidade genética de um grupo de 168 cultivares brasileiras de soja. Os dezoito locos utilizados apresentaram em média 5,06 alelos por loco e coeficiente de diversidade genética médio de 0,58. O dendrograma final resultante da matriz de distância genética de Roger modificado por Wright, apresentou boa concordância com a ancestralidade dos grupos formados. Também foi estimado os coeficientes de parentesco entre as cultivares, sendo observada variação de 0 a 1 com média de 0,18, enquanto que as similaridades para os locos microssatélites (1- GD) variou de 0,01 a 0,90 com média de 0,25. A correlação entre as duas matrizes obtidas determinada pelo teste Z de Mantel apresentou valor baixo, 0,31, mas significativo (p<0,001). Os resultados obtidos sugerem que os locos microssatélites aliados às informações de genealogia proporcionam melhor análise da diversidade genética de cultivares de soja.

Fingerprints of soybean total isoflavone by HPLC / 中草药

Objective To study the HPLC fingerprints of isoflavones from different medicinal plants of G.max and establish a sensitive and specific method for controlling the quality of the soybean isoflavone.Methods The gradient elution mode was applied in chromatographic separation.A C_(18) column(250 mm?4.6 mm,5 ?m) was used with the mobile phase: ice acetic acid water solution(pH value 3.2)-methanol,flow rate: 0.6 mL/min,detecting wavelength: 261 nm,and the column temperature: room temperature.All 25 samples collected from different species were determined.The clustering analysis and the software of similarity analysis were applied for datum analysis.Results This method had a good repeatability and reproducibility.The ratio of peaks′ area from distinct samples were different.Conclusion The method can show the difference of chemical compositions among species completely and can be used as a quality control method for soybean.