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Soybean (Glycine max (L.) Merr.), an important crop grown for its protein source for humans and livestock, is widely introduced in different parts of Ethiopia. However, the productivity of the crop is far below its potential in the country due to different factors, among which low soil fertility is a major contributor. Hence, this field experiment was conducted with the objective of determining the optimum rate of starter nitrogen (N) and bradyrhizobium inoculation on yield and yield components of soybean in the 2019 and 2020 cropping seasons. Two levels of bradyrhizobia (inoculated and uninoculated) and six levels of starter nitrogen (0, 9, 18, 27, 36, and 54 kg N ha−1) were arranged in a factorial design. The result showed that soybean grain yield increased by about 60 % with inoculation of bradyrhizobia applied with low rates of starter nitrogen fertilizer, regardless of cropping seasons. Application of a nitrogen rate above 18 kg N ha−1 leads to yield decline and has no significant variation from bradyrhizobia inoculation only. Regardless of the cropping seasons, elevated levels of starter nitrogen beyond 27 kg ha−1 suppressed nodulation and nodule dry matter. Starter N at a rate of 9 and 18 kg N ha−1 improved soybean nodulation by 125–130 % over control and 95 % over bradyrhizobia inoculation alone. Thus, it was recommended to apply bradyrhizobia strains with 9 or 18 kg N ha−1 starter nitrogen for better yield of soybean as well as adequate nitrogen fixation in Nitisols having moderate soil nitrogen levels similar to the Teppi areas.

Abstract The Brazilian Midwest is responsible for 54.3% of the country’s soybean production. Adequate storage technologies are essential to maintain physical, physiological, and sanitary seed qualities while also minimizing deterioration processes and consequent germination and vigor declines. In this context, the aim of the present study was to evaluate the physiological potential and physical qualities of soybean seeds stored under different environmental conditions and storage bag depths. Assays were carried out in September 2021 employing Foco 74i77 RSF IPRO cultivar seeds stored from April to August 2021 under three conditions, as follows: chilled at an average temperature of ≤20 °C, at an average temperature of ≤25 °C using a with blanket, and in without blanket warehouse structure at an average temperature of ≥25 °C with no with blanket. A completely randomized 3x3 factorial experimental design was applied, comprising three storage environments and three bag positions (top, middle, and bottom), with three replication each. Physical, physiological, and biochemical tests were performed on the stored seeds. The findings indicate better seed preservation in the chilled environment or when using a with blanket, with significant differences noted for seeds stored the middle of the storage bag. Therefore, soybean seed storage in a chilled environment or using a with blanket aids in slowing down the seed deterioration processes, preserving physiological quality and vigor compared to a conventional storage environment. Additionally, the quality of soybean seeds stored under these conditions in the middle of storage bags is maintained.

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Soybean (Glycine max L.) is a crop with prominence in Brazil and worldwide. The increase in soybean production and production capacity is associated with scientific and technological advances in the productive sector. One of these advances is the use of biostimulants. In this sense, this work aimed to review current knowledge about the effects of biostimulants on soybeans, highlighting the direct or indirect response of the plant when using such substances. This review was carried out through a research with a qualitative approach, being considered a literature review of the narrative type, using other studies and research at the same theme, in high impact magazines from the last five years or more that were relevant to the study, with subsequent critical reading about the subject. Based on found results, it is clear the use of biostimulants in soybeans is a potential alternative input for increasing the growth and development of the crop, as they are able to provide increments in its productive variables. However, further research is needed in order to provide better information on agronomic interests.

As queimadas na Amazônia emitem quantidade significativa de gases para a atmosfera, os quais são responsáveis pela formação de ozônio, um poluente altamente oxidante que pode causar efeitos negativos à produção agrícola. O presente trabalho teve como objetivo avaliar o crescimento (altura, diâmetro do caule, número de folhas e de vagens) e acúmulo de biomassa (peso seco de raiz, vagens e grãos) da cultivar “Tracajá” de Glycine max L. (soja) plantada, rotineiramente, em áreas amazônicas. Para tanto, foram realizados dois experimentos em que as plantas de soja foram mantidas no ambiente do Parque Estadual das Fontes do Ipiranga (PEFI), afetado por ozônio, e em casa de vegetação com ar filtrado. Os resultados mostraram os efeitos do ozônio no crescimento e produção de biomassa de soja. A Análise de Componentes Principais (ACP) indicou forte associação dos valores de altura, diâmetro do caule, número de folhas e vagens com as unidades amostrais da casa de vegetação. Diferenças estatísticas foram observadas no acúmulo de biomassa entre as plantas mantidas sob os dois tratamentos, sendo que a biomassa das sementes foi a variável mais afetada. Assim, a produtividade de soja “Tracajá”, cultivada em locais atingidos por ozônio na região amazônica, possivelmente vem sendo afetada por esse poluente.

Para obtenção de maiores produtividades em lavouras de soja, o uso de novos produtos, a exemplo dos biofertilizantes, tem tido boa aceitação pelos produtores, seja para aplicação via solo ou foliar. Desse modo, o objetivo do presente estudo foi avaliar o efeito dos biofertilizantes comerciais VitaComplex® (a base de melaço de cana-de-açucar + aminoácidos) e AminoVita® (a base de ácido cítrico, sacarídeos e resíduos de abate de animais) em caracteres agronômicos e produtividade da soja. Os produtos foram aplicados via foliar em estádios vegetativos e reprodutivos. Foram avaliados a altura de plantas, diâmetro de caule, SPAD, carbono orgânico foliar (C.O) e produtividade. Diâmetro de caule altura, índice SPAD e C.O não apresentaram diferenças estatísticas significativas em função das doses testadas. Para produtividade, houveram ganhos de até 1,78 t ha-1, quando comparado ao tratamento controle. Tanto a aplicação individual ou em conjunto dos produtos testados ocasionaram aumentos na produtividade de soja.

Genotype by environment interaction (GEI) is a phenomenon that occurs in heterogeneous environments that slows breeding progress by preventing the selection of superior cultivars for breeding and commercialization. Therefore, the objectives of this study were to find out how GEI impacts soybean output and to identify the most adapted and stable genotypes. Moreover, to look at the possibility of other mega environments for testing in the future. The experiments were grown for two years in a four-replicated randomized block design at each environment. Over the course of several harvests, yield components, days to flowering, days to maturity, plant height, the number of pods per plants, the number of seeds per plant, hundred seed weight and grain yield per hectare were evaluated in the main for 2018 and 2019.To analyze the stability performance of the genotypes, general linear method, GGE and Additive main effect and multiplicative interaction effects analysis (AMMI) and ASV rank analysis were applied. The GGE biplot revealed that the GGE biplots explained 74.29% of the total variation distributed as,56.69% and 17.62% of sum of squares between principal component PC1 and PC2, respectively whereas, AMMI model, the first two interaction principal component axes (IPCA1 and IPCA2) explained 47.74% and 26.62% of the variation due to GEI, respectively, exposed genotypes identified the five as best performer. The results from the four distinct stability statistics AMMI biplot (G8, G2, G1, G11), ASV (G1, G11; (GSI; G9, G1, G11) and (GGE: G2, G8, G9) are taken into account together with the genotypes` grand mean. The genotypes JM-CLK/CRFD-15-SD (G8) and 5002T (G1), which rank among the best and have the highest seed output, are suitable for hybridization as a parent and commercial production. Therefore, genotypes JM-CLK/CRFD-15-SD (G8) and 5002T(G1) have the highest seed output were among the best and thus could be recommended for release as a new soybean varieties cultivation across.

ABSTRACT The aim of this study was to evaluate the development, yield and its components of soybean sown in hill drop method with variation in hole spacing, compared to the conventional sowing method in lines. The experiment was conducted in a randomized block design, with six treatments and four replications, using the variety M7739 RR IPRO with four plans per hole. The treatments consisted of population variation from 50 to 150% of the recommended one, obtained by the holes spacing alteration and a control sowed in lines with the recommended population. The control was compared to the other treatments using the Dunnett test and the hole spacing effect was evaluated by regression. The cultivar 7739 RR IPRO responds to hill drop sowing, obtaining even in lower populations, yields similar to the conventional sowing in lines. The highest yields in the hill drop sowing method are obtained in the higher populations, with a linear decrease in yield with an increase in hole spacing. Increasing hole spacing increases the number of pods and branches and reduces leaf cover, light interceptcion, plant height and first pod height.

The question of the spray volume for applying agrochemicals to plants has and still demands studies to continuously search for guiding parameters for technicians due to the several variables involving application technology. This experiment aimed to determine the best spray volume for applying pesticides with a boom sprayer to soybean (Glycine max) and wheat (Triticum aestivum) crops. The experiment had a completely randomized blocks design with five treatments and five replications. In soybean (crop year 2011/12), the treatments were the control (no pesticide application) and spray volume applications of 50, 100, 150, and 200 L ha-1. For wheat (crop year 2012), the treatments were the control and spray volumes of 75, 100, 125, and 150 L ha-1. The variables analyzed were the yield components. The study concluded the need for applying foliar fertilizers and performing the chemical control of diseases and pests in soybean and wheat crops. The spray volumes of 50 L ha-1 for soybeans and 75 L ha-1 for wheat were satisfactory for spraying agrochemicals with a ground bar sprayer on plants.

A wide range of soybean cultivars is available on the market and understanding the physiological response and yield of these materials is fundamental to develop new management systems. Thus, the objective of the present study was to assess ecophysiological parameters and yield of soybean cultivars under field conditions. The experiment was carried out on a farm located in the municipality of Açailândia, Maranhão, Brazil. Three commercial cultivars were used (SC1, SC2 and SC3), and gas exchanges, SPAD index, Fv/Fm, photosynthesis index (PI), instantaneous water use efficiency (WUE) and intrinsic instantaneous of the use of water (iWUE) were assessed during the vegetative (V5) and reproductive (R5) stages. In addition, the biomass and production components were obtained. A randomized complete block design was used, with three cultivars and six replications. SC2 obtained the best mean for the photochemical variables. SC2 was more efficient at both development stages in WUE, but the maximum iWUE values were obtained in SC3. The SC2 cultivar obtained the best responses in the main variables analyzed, resulting in a higher yield.

ABSTRACT Agriculture has caused numerous concerns regarding the preservation of natural resources. In this context, agroforestry systems are emerging as a more sustainable alternative. The present study aimed to evaluate growth characteristics, radiation use efficiency, biomass partition, and yield of soybean grown in two agroforestry systems and full sun. A field experiment was conducted in Southern Brazil during the 2014/2015 crop year, in which transmissivity of solar radiation, leaf area index, radiation use efficiency, and yield of soybean were evaluated. The solar radiation dynamics varied among the study factors, mainly due to the agroforestry arrangements. Shading influenced the leaf area index, radiation use efficiency, biomass partition, and soybean yield. Based on the soybean yield values generated in this study, the use of more spaced agroforestry arrangements and Peltophorum dubium forest species is recommended. However, because the yield values were below the expected levels, it is not yet possible to confirm the full potential of soybean crop in agroforestry systems. Thus, new studies should be conducted in order to generate alternatives that make soybean cultivation feasible in agroforestry systems, such as assessing the use of more spaced agroforestry arrangements, the insertion of the soybean crop in the initial years of cultivation of agroforestry, as well as reduce intraspecific competition by decreasing the plant population of the crop.

Drought is one of the most important factors limiting the successful production of cultivated plants. One of the most sensitive stage to the water deficit in plants is seed germination. There are various methods of pre-sowing treatments that aim to reduce the negative impact of drought stress and improve seed germination. One of them is priming seeds. The aim of this experiment was to examine the effect of priming seeds in solutions - KNO3 (1%), ascorbic acid - AsA (100 mgl-1) and potassium chloride KCl (1%) on the reduction of the negative effect of drought stress. The effect of drought stress was simulated using different concentrations of PEG 6000 (0 (control), -0.30, -0.51, -0.80 MPa). The results of the research showed that with the increase of water deficiency, the effect of priming seeds is greater. At the water potential of the solution of -0.30 MPa, germination energy and seed germination increased on average by 6.77% and 5.08%, while at the water potential of the solution of -0.80 MPa, the increase was 19.28% and 16.75%, respectively. Also, priming seeds significantly reduced the intensity of lipid peroxidation and the content of free proline. From all the above, it can be concluded that priming of seeds is a method that can serve to improve the germination of soybean seeds in conditions of drought stress.

O cobre em elevada concentração no solo torna-se tóxico ao desenvolvimento das plantas e microrganismo. O trabalho objetivou selecionar fungos micorrízicos arbusculares eficientes para o desenvolvimento e produtividade da soja cultivada em solo contaminado com cobre. O delineamento experimental foi em Inteiramente casualizado em arranjo fatorial 7 × 4, sendo, sete doses de cobre (0, 80, 160, 240, 320, 400 e 480 mg de cobre kg-1de solo), quatro inóculos (testemunha sem inoculação e três fungos micorrízicos: Acaulospora colombiana, Dentiscutata heterogama e Rhizophagus clarus), com 7 repetições. Avaliou-se a altura da parte aérea, diâmetro do colo, número de grão por planta, massa seca da parte aérea e sistema radicular, área foliar, área superficial específica de raízes, teores e acúmulo de cobre na parte aérea, radicular e no grão, parâmetros da clorofila, e porcentagem de colonização micorrízica. A inoculação com fungos micorrízicos arbusculares Acaulospora colombiana, Dentiscutata heterogama, Rhizophagus clarus aumenta os parâmetros fenológicos e fisiológicos da soja e a sua produtividade soja em solo contaminado com até 480 mg kg-1de cobre aplicado no solo. O isolado Rhizophagus clarus promove maior desenvolvimento da soja e aumenta sua produtividade em solo contaminado com até 480 mg kg-1de cobre aplicado no solo em relação aos demais isolados.

The boron (B) fertilization in soybean is important to ensure great yields. Boron correction must be applied in deficient soils repairing losses, exports and leaching. The objective of this study was to evaluate the effects of doses, methods and times of application of B in soybean B content and yield. The field experiments were conducted during the 2015/16 and 2016/17 cropping seasons and set as a randomized block design with nine treatments (0, 0.5, 1, 1.5, 2 kg ha-1 of B, 0.5 kg ha-1 of B mixed with NPK (02-28-18) in furrow during sowing, foliar application with 0.3 kg ha-1 of B in V4 soybean stage, foliar application with 0.3 kg ha-1 of B in R1 soybean stage, and foliar application of 0.15 kg ha-1 in V4 plus 0.15 kg ha-1 of B in R1 soybean stage) and four replications. Boric acid was the B source and the variables analyzed were: B leaf content, B exported in seeds, number of pods per plant, number of seeds per pod, weight of 100 seeds (g) and productivity (kg ha-1). The levels of B in leaf were between 30.1 and 43.8 mg kg-1 and between 65.0 and 92.6 mg kg-1 in the 2015/16 and 2016/17 growing season, respectively. Exports of B in seeds were estimated between 166 and 248 g ha-1 and between 208.9 to 260.8 g ha-1 in the 2015/16 and 2016/17 growing season, respectively. Great productivity (3,820 kg ha-1) was observed in the 2016/17 growing season, with an estimated dose of 0.95 kg ha-1 of B.

Brazil is a major soybean production country and cultivate yearly more than 36 million hectares. Several factors have been reported reducing soybean production and occurrence of diseases is one of the most important. Some diseases such as the pod and stem blight (Diaporthe phaseolorum var. sojae) can limit soybean yield by shortening plant cycle and reducing seed quality. Field experiments were conducted aiming to evaluate the effect of row spacing, soybean cultivar and fungicide application on the incidence of pod and stem blight on soybean. The trial was carried out twice, with planting date at 11/15/2012 and 12/15/2012, in Planaltina-DF, Brazil. Treatments were arranged in a split-split plot scheme obeying the randomized block design. The factors evaluated were row spacing (42, 60 and 75 cm), soybean cultivars (“Syn1180RR” and “Syn1080RR”) and spray or not the fungicide Boscalid (500 g a.i./ha) at R1 and R3 soybean growth stages. Disease incidence was assessed on stems at the harvest time and on seeds after harvest and yield was estimated. Results obtained show that broader row spacing increased disease incidence on stems and seed, cultivar “Syn1180RR” was more susceptible than “Syn1080RR” and fungicide application reduced disease incidence. Pod and stem blight significantly reduced soybean yield.

Soybeans are a grain-producing species of high international demand and occupy a prominent position in the Brazilian economy. The success of this crop in Brazil is due to public and private investments in production technologies and to breeding programs. It is through the seed that the genetic advances reach the producer. In this context, the success of a cultivar and high productivity depend on the quality of the seed. In view of the above, the objectives of the study were to evaluate the physiological quality of soybean cultivar seeds at different harvesting times. The experiment was conducted in an experimental area located at Fazenda Capim Branco, belonging to the Federal University of Uberlândia, in the 2016/2017 harvest. Ten soybean cultivars were evaluated (CD 2737 RR, UFUS 7415, UFUS 7910, UFUS Milionária, UFUS 7801, NA 5909 RG, UFUS 8301, TMG 7062 IPRO, UFUS Xavante and UFUS 6901) at four harvest times (R7, R8, R8+15, R8+30), constituting a 10 x 4 factorial. The experiment was carried out in a randomized complete block design with four replicates. For the evaluation of the physiological quality, germination, electrical conductivity and fresh matter and dry matter of seedlings tests were performed. In all tests the physiological quality of the seeds decreased with the harvest delay. Emphasis was placed on the cultivar NA 5909 RG, which showed the best means to delay the harvest in 15 and 30 days.

A model to estimate the damage caused by white mold to soybean yield from experimental field data gathered during the summer season of 2009-10 was generated. Six soybean cultivars were grown on six sites of the Cerrados region, resulting in a total of nine separate experiments. The gradient of disease intensity (plant stem incidence) and yield was generated through the application of different fungicides and rates three times over the course of the season. The disease incidence in plant stems was evaluated at the R1, R5.2 and R5.5 growing stages. Manual harvest at the physiological ripening stage was followed by grain drying, threshing, and cleaning. Finally, grain yield was estimated in kg/ha, and regression analysis was performed. Nine linear equations representing the damage function were generated. The mean damage function was y = - 6.7 x + 1,000, where y represents grain yield normalized to 1,000 kg/ha and x represents WM incidence in plants. To appraise the damage caused by various disease intensities, these models should first be validated. Damage coefficients may be used to determine the level of economic damage.

A persistência no solo de herbicidas do grupo das triazinas é dependente de basicamente de condições de precipitação e características do solo. Objetivou-se avaliar o efeito residual de diferentes épocas de aplicação e doses de atrazina e atrazina + simazina para a cultura da soja. Conduziram-se experimentos a campo e casa de vegetação. A campo utilizou-se o delineamento de parcelas subdivididas com quatro repetições, sendo o fator A composto por épocas de aplicação 56, 49, 42, 35, 28, 21 e 14 dias antes da semeadura da soja; e fator B, pelos herbicidas atrazina e atrazina + simazina. Para o experimento em casa de vegetação o delineamento inteiramente casualizados, o fator A foi constituído de doses 0, 570, 1.140, 1.715, 2.285, 2.860, 3.430 e 4.000 g i.a.ha-1; e fator B pelos herbicidas atrazina e atrazina + simazina. A aplicação dos tratamentos foi realizada com pulverizador costal pressurizado por CO2, após a aplicação realizou-se a semeadura da soja. A campo avaliou-se o estande de plantas, fitotoxicidade, estatura, altura de inserção do primeiro entrenó, teor de clorofila e produtividade. Em casa de vegetação foram avaliados fitotoxicidade, estatura de plantas, área foliar e massa seca. Após os dados foram submetidos a análise de variância e quando significativas as medias foram comparadas pelo teste Tukey a 5%. A simulação de residual dos herbicidas atrazina e atrazina + simazina no solo apresentam comportamento similares quanto aos efeitos na soja. No experimento a campo, devido às altas precipitações ocorridas no intervalo entre as aplicações dos herbicidas e a semeadura da soja, não foram observados efeitos fitotóxicos ou redução na produtividade da cultura. Em casa de vegetação, o aumento da dose residual dos herbicidas no solo incrementou os efeitos tóxicos na soja.

The aim of this study was to evaluate the chemical control of Asian soybean rust (Phakopsora pachyrhizi Syd. & P. Syd.) using different tips and spray nozzles under controlled conditions. Rooted trifolia placed inside an acrylic box containing macronutrients, micronutrients and vitamins were treated with epoxiconazol + pyraclostrobin, ciproconazol + azoxystrobin and tebuconazol fungicides. These fungicides were sprayed at a height of 0.5 m with two knapsack sprayers pressurized with CO2 gas (drop generator in four spray tips spaced by 0.5 m from each other) and another rotating nozzle (drop generator through a rotating nozzle). Untreated trifolia were controls. Water sensitive paper was placed next to each acrylic box to obtain median volume diameter (MVD), number of droplets.cm-2 and coverage (%). Trifolia were inoculated 24 hours after that these were treated with fungicide, using a spore concentration adjusted to 2 x 104 uredospores.mL-1. Then, the number of lesions and uredia.cm-2 in central leaflets were quantified. Lower number of lesions and uredia.cm-2 were observed in leaflets treated with two fungicide mixtures using an AIRMIX 11001 tip. A lower VMD was found in leaflets sprayed with the fungicides azoxystrobin + epoxiconazol and tebuconazol, when compared to the leaflets treated with another mixture. The Asian rust control, as well as the number of droplets.cm-2 and coverage, seems to be dependent on the interactions among fungicides and tips or nozzles.

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Yield and quality performances of 27 soybean cultivars were evaluated in two years field experiment between 2015 and 2016 at the Experimental Farm of Faculty of Agricultural Sciences and Technologies, Nigde Omer Halisdemir University, Nigde, located in the Central Anatolia Region. The field experiments were laid out in the randomized complete block design with three replications in each year. The main phenological stages of development such as time to emergence, flowering, time to pod formation and time to maturity were determined as calendar days. Plant height, the first pod height, numbers of branch, pod and seed per plant, number of seed per pod, 100-seed weight, protein content, oil content and seed yield per decar were determined as yield and quality parameters. The results of two-year study revealed that the soybean cultivars differed significantly for all characters studied under Nigde conditions. It was also observed that yield and quality performances of cultivars fluctuated in years. Average seed yield values of cultivars were ranged from 135.2 kg/da-1 (Inton-I. maturity group) to 295.8 kg/da-1 (Adasoy-IV maturity group) in 2015 and 2016. In two years mean, the cultivars Adasoy, Sa-88 and Nova were determined as the most promising genotypes for main crop production in Nigde conditions.

The objective of this study was to produce silage from intercropped RR glyphosate tolerant corn (RR - Roundup Ready) and RR soybeans under Brazilian Cerrado conditions. The research was carried out in off-season between February and June 2015, in Rio Verde, Goiás (Brazil). In the experimental period the rainfall was 865 mm and the average temperature of 23.7°C. Two trials were performed. The first had corn rows spaced in 1 m with a row of soybeans in the interrow. The second had double corn rows interspersed with one row of soybeans, all spaced in 0.50 m. In both trials, we used a randomized block design, in a 2x2+3 factorial scheme, with four replications. Primary factor consisted of two types of pre-sowing fertilization: one only in corn rows and the other over the total area. The secondary factor corresponded to two soybean varieties: medium and late cycle variety. In addition, three control treatments were made: one of corn and two of soybeans. The corn cutoff point was at the hard farinaceous stage when the milk line reaches half the grain, and in the sole crop soybean at the R5.5 final phase of grain filling. Silage was stored in PVC experimental silos for 60 days. The intercropped treatments, in both spatial arrangements, promoted increases in neutral detergent fiber and acid detergent fiber contents. Soybean monoculture presented high values of crude protein and ethereal extract. There were higher effluent losses in medium-cycle soybean variety silage when it was grown in single cropping. However, the lowest effluent losses were recorded for silages of medium-cycle soybean intercropped under a double row pre-sowing corn fertilization system. The soybeans mixed silages produced together with corn under off-season conditions did not yield satisfactory results.

In recent decades, the expansion of soybean production in Brazil has been observed. This advance was motivated by the search of environments with better cultivation conditions, as well as the development of genotypes with wide adaptation. The diversity of "environments" hinders the process of selection and recommendation of cultivars, since the productive potential of a cultivar is given as a function of the sum of the genotype effect, the environment and the interaction between the latter two (G x E). In the case of this G x E interaction, regional studies are necessary in order to detail the differential behavior of the cultivars. Thus, the objective of this work was to evaluate the genotype interaction by environments, adaptability and phenotypic stability for grain yield, of fifteen soybean cultivars, in four sowing seasons, in order to identify cultivars that combine high productive potential, predictability of behavior and adaptation to the edaphoclimatic conditions of Uberlândia-MG. The trials were conducted at the Experimental Farm Capim Branco, in Uberlândia-MG. Fifteen soybean cultivars were evaluated in four sowing seasons (October 23, 2016, November 19, 2016, December 10, 2016 and January 14, 2017), in relation to grain yield. The experimental design was of randomized complete blocks, with three replications, in each season. Data were submitted to individual and joint analyzes. The G x E interaction was decomposed by the method proposed by Cruz and Castoldi (1991). The differential behavior of the genotypes was detailed by the adaptability and phenotypic stability by the methods of Eberhart and Russell (1966), Lin and Binns (1988) modified by Carneiro (1998), AMMI and Centroid. By the analysis of joint variance, it was observed the existence of the cultivar interaction by sowing times (C x E), for the grain yield trait, at the 5 % probability level by the F test. The C x E was predominantly complex in nature. The cultivar CD 2737 RR presented satisfactory results for the four sowing seasons in Uberlândia-MG, with high grain yield and predictability of behavior, by the evaluated methods. The cultivar NS 6909 IPRO was classified into favorable environments by the methods of Eberhart and Russell (1966) and Lin and Binns (1988) modified by Carneiro (1998). Considering Lin and Binns (1988) modified by Carneiro (1998) and Centroid the cultivar that is also classified for this cultivation condition is UFUS 8301. By AMMI, UFUS 7415, CD 2737 RR and UFUS Milionária are considered stable and adaptable.

Soybean has great economic importance in the world accordingly, this legume has been exploited in breeding programs aiming to provide cultivars with extensive grain yield, tolerant to pests and diseases, and adapted to different soil and climatic conditions. Therefore, the objectives of this work were to evaluate genetic parameters and correlations between soybean traits to select lineages to increase yield and improve agronomic traits. Experiments were carried out on the Capim Branco farm, of the Federal University of Uberlândia, harvest in 2016/2017. Fifteen morph-agronomic traits were assessed on twenty-two genotypes in a randomized complete block design with three replicates. Agronomic traits related to cycle, height, number of nodes and total pods have shown coefficients of genotypic determination higher than 70%. In addition, coefficients of variation of the number of days to the flowering and number of days to maturity were equal to 3.79% and 4.87%, respectively, indicating high homogeneity of data and low random variation. Among evaluated traits, ten have presented the ratios between the coefficient of genetic variation (CVg) and coefficient of environmental variation (CVe) above one, demonstrating high success likelihood in the selection of these traits. Fifteen genotypes have presented grain yield above the national average of the 2016/2017 harvest, which was 2882 kg h-1. Significant phenotypic correlations between traits ranged from -0.49 to 0.89, however genotype correlation was higher than the phenotypic ones, indicating that genetic factors have contributed more than the environmental factors. Traits related to cycle, height, and the number of nodes in the main stem have presented measures of H² and CVg / CVe with extensive magnitudes, evidencing the possibility of selection lineages having superior traits in the Soybean Breeding Program of the Federal University of Uberlândia. To increasing grain yield, the traits Number of pods of three grains and the Total number of pods were identified as appropriated to indirect selection based on the phenotypic and genotypic correlations. The 2lP14, B2P1, B2P28, B1P33 and 2AP11 lineages stand out as superior genotypes to direct selection.

Soybeans sowing in different plants’ spatial distribution can influence the phytosanitary management of this crop and, consequently, impact on grains yield. This study was carried out to evaluate the effect of plants arrangements on infestation and control of caterpillars, the deposition of spray syrup as well as assess the agronomic performance of soybean cultivated in the Brazilian Cerrado. The assay was performed during two consecutive seasons in a randomized complete block design with four replications. Soybean cultivation was implemented in 0.50 m spacing between rows, crossed (0.50 m x 0.50 m), twin rows (0.25 m / 0.75 m), and narrow (0.25 m). In the reproductive stage of plants, both crossed and narrow arrangements showed higher caterpillars’ incidence. There was a more evident risk of caterpillar incidence in arrangements that promoted better equidistance among plants. This risk was mitigated when taking into account both control and overlap of syrup, which could be incremented into inferior canopy with the enhancement of application rate. The increase in application rate from 75 to 150 L ha-1 promoted superior spray deposition volumes. Increases in grain yield was noted in the narrow arrangement.

O objetivo deste estudo foi avaliar o comportamento de diferentes genótipos de soja quanto à tolerância à ferrugem-asiática-da-soja (FAS), em condições de campo. Foram conduzidos experimentos, em dois anos consecutivos, no delineamento experimental de blocos ao acaso, com quatro repetições, em esquema fatorial, com oito níveis para genótipos de soja e três para aplicação de fungicida na parte aérea das plantas. Verificou-se suficiente variabilidade entre os genótipos avaliados quanto à tolerância à FAS, com alta interação com o ano. Os genótipos mais precoces apresentaram reduções de produtividade inferiores aos de ciclo mais tardio. A cultivar 'BRS 239' foi caracterizada como tolerante à FAS, pelo fato de as produtividades com e sem controle da doença não apresentarem diferenças significativas. A cultivar 'BRSGO 7560', apesar de apresentar ciclo mais tardio, comportou-se como tolerante à FAS, sem redução significativa da produtividade em condições de estresse pelo patógeno, na ausência de controle da doença, o que garantiu maior estabilidade produtiva.

Durante o ano agrícola de 2012/2013, no município de Campo Novo do Parecis, MT, objetivou-se analisar a variabilidade espacial de atributos da soja e da fertilidade num Latossolo Vermelho distrófico típico cultivado sob plantio direto. Foi instalada a malha de amostragem para a coleta de dados numa área de 5,0 ha. Foram avaliadas a produtividade de grãos de soja, população de plantas, matéria orgânica, P, Ca+2, Mg+2, K+, Al+3, H+ + Al+3, pH (CaCl2), soma de bases, capacidade de troca catiônica e saturação por bases. Efetuou-se a análise descritiva clássica, com auxílio do software estatístico SAS, análise de correlação e regressão com o Excel, sendo modelados semivariogramas para todos os atributos, obtendo-se as respectivas validações cruzadas e mapas de krigagens com o GS+ 7.0. A maior parte dos atributos pesquisados apresentou dependência espacial, sendo possível modelar seus respectivos semivariogramas, predominantemente do tipo gaussiano. Os alcances geoestatísticos utilizados para os atributos analisados não deverão ser inferiores a 43,8 m, por serem a distância na qual os valores dos atributos estão relacionados entre si. O estudo da variabilidade dos atributos do solo bem como a adoção de técnicas que auxiliem no manejo do solo, como a geoestatística, é essencial ao adequado desenvolvimento vegetal.

O principal objetivo da aplicação de produtos fitossanitários é o controle eficiente de insetos-praga, patógenos e plantas daninhas. O arranjo espacial da cultura pode interferir na estrutura morfológica da planta e alterar a arquitetura da planta, criando condições diferenciadas para a penetração das gotas no dossel. Este trabalho teve como objetivo avaliar o efeito de diferentes estandes e espaçamentos entrelinhas na deposição de calda de pulverização e na produtividade da cultura da soja. Foi utilizado um delineamento experimental em blocos casualizados no esquema fatorial 2x6, sendo dois estandes (160.000 e 240.000 plantas ha-1) e seis espaçamentos entrelinhas (0,30; 0,40; 0,50; 0,60; 0,70m e 0,50m em semeadura com linhas cruzadas), com quatro repetições. Foram avaliados o tempo de fechamento das entrelinhas, a porcentagem de fechamento das entrelinhas, a deposição de calda de pulverização nos terços superior, médio e inferior da planta, a razão deposição entre o terço superior e inferior do dossel e a produtividade. Os tratamentos com espaçamentos de 0,6 e 0,7m não atingiram 100% de fechamento. Houve maior deposição no terço inferior nas parcelas semeadas em linhas cruzadas. A maior produtividade de grãos ocorreu no espaçamento de 0,4m. Os resultados indicam que a alteração do arranjo espacial pode aumentar o tempo de fechamento e/ou reduzir o fechamento total das entrelinhas da soja, possibilitando controle eficiente das doenças de baixeiro.

During the 2012/2013 agricultural year, in the city of Campo Novo do Parecis, MT, the study aimed to analyze the spatial variability of soybean and of the fertility attributes of Typic Tropudox under no-tillage. The sampling grid for data collect was installed in an area of 5.0 ha. The productivity of soybeans, plant population, organic matter, P, Ca+2, Mg+2, K+, Al+3, H+ + Al+3, pH (CaCl2), sum bases, cation exchange capacity and base saturation were evaluated. A classic descriptive analysis was carried out with the help of the SAS statistical software, correlation and regression analysis with Excel and semivariograms were then modeled for all attributes, giving the respective cross-validations and kriging charts with the GS+ 7.0 software. Most surveyed attributes presented spatial dependence, and modeled their semivariograms by predominantly Gaussian type. The geostatistical ranges used for the attributes analyzed should not be less than 43.8 m, being the distance at which the attribute values are related to each other. The study of the variability of soil attributes and the adoption of techniques that help in the management of soil, such as geostatistics, is essential to proper plant development. [ABSTRACT FROM AUTHOR]

This work had as its objective to study the phenotypic stability of soybean genotypes, the grain yield, in eight experiments, four in Gurupi-TO, and four in Palmas-TO, its conducted through 2008 to 2012. The experiments were done with completely randomized blocks, with four replications and eleven soybean genotypes. The following methods of stability were used: Eberhart and Russel (1966), Lin and Binns (1988) modified by Carneiro (1998), and Annicchiarico (1992). The methods of Lin (1982) and Cruz and Castoldi (1991) were used for the analysis of environmental stratification and dissimilarity. Theaverage grain yield of the genotypes in the experiments was 2,931 kg ha-1. The result of analysis of variance had shown significanteffects of the environments and the interaction of G x E, and this was predominant complex in all pairs of environments. The genotype TMG 131 RR was more appropriate for the two environmental conditions, favorable and unfavorable. The genotype TMG 132 RR was more appropriate for the favorable conditions. The methods used complete each one and, when they were used together can to increase the confidence in relation the classification and indication of soybean genotype for specific environments. = Objetivou-se com este trabalho estudar a estabilidade fenotípica de cultivares de soja, quanto à produção de grãos, em oito ensaios, quatro na cidade de Gurupi-TO e, quatro na cidade de Palmas - TO, conduzidos durante os anos de 2008 a2012. Os ensaios foram instalados com delineamento em blocos casualizados, com quatro repetições, e onze cultivares de soja.Foram utilizadas as metodologias de análise de estabilidade de Eberhart e Russell (1966), Lin e Binns (1988) modificado porCarneiro (1998), e Annicchiarico (1992) e também, as de Lin (1982) e Cruz e Castoldi (1991) nas análises de estratificação edissimilaridade ambiental. A produção média das cultivares nos ensaios foi de 2.931 kg ha-1 de grãos. O resultado da análise devariância conjunta mostrou efeitos significativos dos ambientes (ensaios) e da interação G x A, a qual foi predominantemente do tipo complexa para todos os pares de ensaios. O genótipo TMG 131 RR foi mais adequado em ambas as condições ambientais (desfavoráveis e favoráveis), tendendo para as desfavoráveis. E o genótipo TMG 132 RR para as favoráveis. As metodologias utilizadas, de modo geral, se completam e, quando usadas conjuntamente, podem aumentar a confiança quanto à classificação e indicação de cultivares de soja para determinados ambientes.

Soybean (Glycine max (L.) Merrill) is a widely grown crop of economic prominence. Brazil is considered as the second largest worldwide producer and exporter. Soybean cyst nematode, Heterodera glycines Ichinohe, in one of the most serious threats for this crop, considered as its most destructive parasite. The first report of this disease in Brazil was recorded during the 1991/1992 harvest. Control of nematodes is more challenging if compared with other plant diseases control. Thus, there is a growing demand to search for alternative control practices that will not harm the environment nor the human being. Therefore, the highly specific bacteria Pasteuria spp. Metchnikoff, represents an auspicious biological control agent against nematodes. The biological control of the soybean cyst nematode with the bacterium Pasteuria nishizawae Sayre has proven an excellent choice and has been studied by different scientists. The objective of this work was to determine the natural occurrence of Pasteuria nishizawae in Brazilian soils. The experiment was performed under greenhouse conditions at the Research unit from Syngenta® in Uberlandia-MG, Brazil, with soil samples originated from soybean planted areas from the Brazilian states of Bahia, Goiás, Mato Grosso and Paraná. Fractions of 150 cm3 of soil were withdrawn to be processed by the centrifugal flotation technique in sucrose solution. Aliquots of 1 mL from the obtained suspension were observed in Peters' chamber with the aid of an inverted light microscope, in order to verify the absence or presence of bacterial endospores attached to the cuticle of the nematodes extracted from the soil samples. The frequency of Pasteuria nishizawae incidence was of 100% within the samples analyzed.

O cultivo integrado da soja com pastagens é uma das principais formas para diversificar os sistemas de produção de grãos no Brasil. O objetivo dessa pesquisa foi avaliar o efeito de intensidades de pastejo em U. ruziziensis, de épocas de dessecação desta em relação à semeadura da soja e da adubação da cultura com nitrogênio mineral sobre o crescimento e o desempenho produtivo da cultivar de soja NK 7059 RR. Foram testadas três alturas de manejo da pastagem de U. ruziziensis (15, 35 e 50 cm), pastejada de forma contínua por seis meses, além de um piquete sem pastejo, constituindo quatro experimentos distintos. Em cada experimento foi utilizado o delineamento de blocos completos casualizados, com três repetições, em esquema de parcelas subdivididas. Nas parcelas foram alocadas quatro épocas de dessecação da pastagem (35, 28, 20 e 8 dias antes da semeadura da soja) e, nas subparcelas, a adubação nitrogenada na soja (sem N ou com 30 kg de N ha-1 na semeadura). Após a análise estatística de cada experimento, realizou-se análise conjunta. As intensidades de pastejo não afetaram significativamente o crescimento e o desempenho da soja cultivada em sucessão. O aumento do intervalo entre a dessecação e a semeadura da soja e a adubação nitrogenada na cultura incrementaram o crescimento e o acúmulo de N no início do ciclo de desenvolvimento da cultura, mas essas diferenças foram inexpressivas no período reprodutivo, não afetando a produtividade de grãos.

Despite the great importance of soybeans in Brazil, there have been few applications of soybean crop modeling on Brazilian conditions. Thus, the objective of this study was to use modified crop models to estimate the depleted and potential soybean crop yield in Brazil. The climatic variable data used in the modified simulation of the soybean crop models were temperature, insolation and rainfall. The data set was taken from 33 counties (28 Sao Paulo state counties, and 5 counties from other states that neighbor São Paulo). Among the models, modifications in the estimation of the leaf area of the soybean crop, which includes corrections for the temperature, shading, senescence, CO2, and biomass partition were proposed; also, the methods of input for the model’s simulation of the climatic variables were reconsidered. The depleted yields were estimated through a water balance, from which the depletion coefficient was estimated. It can be concluded that the adaptation soybean growth crop model might be used to predict the results of the depleted and potential yield of soybeans, and it can also be used to indicate better locations and periods of tillage.Aplicações de modelos de previsão de produtividade na cultura da soja são muito raros. Assim, o objetivo desta pesquisa foi realizar a estimação da produtividade deplecionada e potencial da cultura de soja, usando modelos de previsão modificados. Os dados climáticos utilizados nos modelos de simulação foram a temperatura, precipitação e insolação. Os dados foram proveniente de 33 municípios (28 do estado de São Paulo, e cinco municípios de estados vizinhos). Dentre os modelos propostos modificados está a estimação da área foliar da soja, com correções para temperatura, sombreamento, senescência, CO2, partição de biomassa, bem como os métodos de simulação das variávies climáticas do “input” para o modelo. As produções deplecionadas foram estimadas através do balanço hídrico, a partir do qual, o coeficiente de depleção foi estimado. Considerando as adaptações do modelo para a cultura da soja, pode-se concluir que o modelo pode ser usado para predição de resultados para produção deplecionada e potencial da soja. Também é possível determinar através do modelo os melhores locais de cultivo da soja no Estado de São Paulo.

The aim of this study was to evaluate the effect of high dilutions of Pulsatilla nigricans in dinamisations 6, 12, 18, 24 and 30 CH on the vigour of soybean seeds subjected to accelerated aging. The experiment was conducted according to a randomised design with 6 treatments and 10 replicates. The treatments consisted of dinamisations 6, 12, 18, 24 and 30 CH and a distilled-water control. After the treatments, the seeds were subjected to accelerated aging (48h at 42ºC) in a growth chamber (25 ± 2ºC). The study evaluated the germination, the length of primary roots and shoots, the fresh weight of roots and shoots and the enzymatic activity of peroxidase (POX-EC1.11.1.7). The variables were analysed by ANOVA, and the means were compared using the Scott-Knott test (p = 0.05). The germination and the fresh weight of roots and shoots of the seedlings treated with Pulsatilla nigricans were higher than the water control, except that CH 30 did not significantly increase the fresh weight of shoots. The dinamisations 6, 24 and 30 CH produced a lower primary root length compared with the control. The dinamisations 12, 18 and 30 CH yielded a greater length of shoots. The total length of seedlings was reduced by the high dilutions 6 and 24 CH.O objetivo do presente trabalho foi de avaliar o efeito de altas diluições de Pulsatilla nigricans nas dinamizações 6, 12, 18, 24 e 30 CH, no vigor de sementes de soja submetidas ao envelhecimento acelerado. O experimento foi conduzido em delineamento inteiramente casualizado com 6 tratamentos e 10 repetições. Os tratamentos foram constituídos das dinamizações 6, 12, 18, 24 e 30 CH e testemunha com água destilada. Após aplicação dos tratamentos, as sementes foram submetidas ao teste de envelhecimento acelerado (48h a 42ºC), em câmara de crescimento (25 ± 2ºC). Avaliou-se a germinação, o comprimento da raiz primária e da parte aérea, massa fresca da raiz e da parte aérea e atividade enzimática da peroxidase (POX- EC1.11 .1.7). As variáveis foram analisadas por ANOVA e as médias comparadas pelo teste Scott-Knott a 5%. A germinação e a massa fresca da raiz e da parte aérea das plântulas tratadas com Pulsatilla nigricans foram superiores ao controle com água, exceto na dinamização 30 CH para massa fresca da parte aérea. As dinamizações 6, 24 e 30 CH tiveram menor comprimento da raiz primaria comparadas ao controle. As dinamizações 12, 18 e 30 CH, apresentaram maior comprimento de parte aérea. O comprimento total de plântulas foi reduzido com as diluições 6 e 24 CH.

With the advance of agriculture, there was consequent rising in environment degradation. Therefore, It is interesting the use of plants which have in their chemical composition substances capable of helping in the control of weeds to minimize the use of pesticides. Hence, the objective of this paper was to evaluate solutions of leucena extract on weeds that are frequent on soybean crop. The treatments were leucena extracts at 0, 20, 40, 60, 80 and 100% at room temperature water and water heated to 80°C. The extracts were obtained by crushing 200g of leucena leaves and mixing them with one liter of distilled water with the help of a blender. Seeds were kept in B.O.D. at a temperature of 25°C, with a photoperiod of 12 hours of light. Evaluations were done on a daily basis, from the first to the last day of the experiment, varying according to the species. Results show a negative interference of the extracts, both hot and cold, in the root length of Ipomoea grandifolia, in the percentage of germination and in the root length of Arrowleaf sida and Hair beggarticks. There was no negative interference in the analyzed parameters for soybean seeds. Thus, the results indicate allelopatic potential of Leucaena leuucocephala as an alternative for the management of weeds without interfering on the development of the soybean crop.Com o desenvolvimento da agricultura surgiram os conseqüentes aumentos na degradação ambiental. Assim, estuda-se a utilização de plantas que possuam em sua composição química substâncias capazes de auxiliar no controle de plantas invasoras, amenizando o uso de agrotóxicos. Desta forma, o objetivo do trabalho foi avaliar soluções de extratos de leucena sobre plantas invasoras que freqüentemente ocorrem na cultura da soja. Foram utilizados como tratamentos os seguintes extratos de leucena nas proporções de: 0, 20, 40, 60, 80 e 100% com água à temperatura ambiente e com água aquecida à 80°C. Os extratos foram obtidos triturando-se 200 g de folhas de leucena em um litro de água destilada, com auxílio de um liquidificador. As sementes foram mantidas em B.O.D. à temperatura de 25°C, com fotoperíodo de 12 horas de luz. As avaliações foram diárias, do primeiro ao último dia de experimento, este variando conforme a espécie. Os resultados demonstraram interferência negativa dos extratos, tanto quente quanto frio, no comprimento de raiz de corda de viola, na porcentagem de germinação e no comprimento de raiz de guanxuma e picão-preto. Não foram constatadas interferências negativas nos parâmetros analisados para as sementes de soja. Sendo assim, os resultados obtidos indicam potencial alelopático da espécie Leucaena leuucocephala como alternativa de manejo de plantas invasoras sem interferir no desenvolvimento da cultura da soja.

This research was carried out from September of 2006 to February of 2007, under greenhouse conditions, in Rio Verde –GO/ Brazil to study the influence of Panicum maximum populational density on the phytoremediation of soil contaminated with picloram. The treatments were the combination of four Panicum maximum (cultivar Tanzânia) populational densities (0, 5, 10 e 15 plants per pot, corresponding to a 0, 122, 244 and 366 plants m-2, respectively) and three rates of picloram (0, 80 and 160 g ha-1 applied directly on the pots, simulating levels of soil contamination). After cultivating the phytoremediator specie on substrate during 100 days, soybean Glycine max L was sown at the same pot, used as a phytotoxicity bioindicator specie. Height of plants and green and dry mass of the above ground part of soybean were evaluated. The population density of the phytoremediate species Tanzania influenced the level of phytotoxicity of the herbicide picloram soybean crop sowed in succession. The population density of , 122 plants m-2 was the most efficient in the decontamination of the soil.O objetivo desse trabalho foi avaliar a influência da densidade populacional de Panicum maximum (cultivar Tanzânia) sobre a fitorremediação de solo contaminado com o herbicida picloram. O experimento foi conduzido em casa-de-vegetação, de setembro de 2006 a fevereiro de 2007. Os tratamentos foram compostos pela combinação entre quatro densidades populacionais da espécie vegetal Panicum maximum (cultivar Tanzânia) (0, 5, 10 e 15 plantas por vaso, equivalentes a 0, 122, 244 e 366 plantas m2, respectivamente) e de três doses do picloram (0, 80 e 160 g ha-1 aplicadas diretamente nos vasos, simulando níveis de contaminação do solo). Após o cultivo da espécie fitorremediadora por 100 dias, efetuou-se, no próprio vaso, a semeadura da espécie bioindicadora da presença do picloram, soja (cultivar Monsoy 6101), na qual foram avaliadas a fitotoxicidade, a altura de plantas e a massa verde e seca da parte aérea. A densidade populacional da espécie fitorremediadora Tanzânia influenciou o nível de fitotoxicidade do herbicida picloram sobre a cultura da soja semeada em sucessão. Das densidades populacionais avaliadas, 122 plantas m-2 foi a mais eficiente na descontaminação do solo.

The objective of the work was to study the influence of the climate on the progress of the soybean rust (Phakopsora pachyrhizi) under field conditions. Two assays were carried out during the 2005/2006 season in Castro and Arapoti regions, Paraná. The epidemic was divided in three periods: sowing until first symptoms of disease; beginning of the disease until severity of 20% and severity of 20% until maximum severity. The rust symptoms occurred in Castro at 78 days and in Arapoti at 82 days after the sowing. The biggest duration of leaf wetness period - Dpm (18 hours) was observed in Castro. During the second period of the epidemic, Arapoti presented apparent infection rate-r (0.18), higher than observed in Castro (0.12). During same period were observed greater rainfall values and greater index of number of days of rain – Indr compared with Castro. The final disease severity was 99.9% in Arapoti and 96% in Castro 96%. It was observed a relation between Dpm with the appearance of the first symptoms and was also observed and relation between precipitation data and Indc with the progress of the epidemic. The ambient conditions had been more favorable to the disease in Arapoti, where bigger value of AACPDp (38.2) was observed and less favorable for Castro (30.4).O trabalho objetivou estudar, em condições de campo, a influência do clima no progresso da ferrugem da soja (Phakopsora pachyrhizi). Dois ensaios foram conduzidos na safra 2005/2006, um na região de Castro e outro em Arapoti, Paraná. Dividiu-se a epidemia em três períodos: semeadura até primeiros sintomas da doença, do início da doença até severidade de 20% e severidade de 20% até severidade máxima. Os sintomas da ferrugem apareceram em Castro aos 78 dias e em Arapoti aos 82 dias após a semeadura. A maior duração do período de molhamento foliar - Dpm (18 horas) foi observada em Castro. No segundo período da epidemia, Arapoti apresentou taxa aparente de infecção-r (0,18), maior do que observado em Castro (0,12). Durante mesmo período foram observados maiores valores de precipitação e maior índice de número de dias de chuva (Indc) quando comparados à Castro. No período final, em Arapoti obteve-se severidade final de 99,9% e em Castro 96%. Observou-se relação entre Dpm com o aparecimento dos primeiros sintomas e também relação entre dados de precipitação e Indc com o progresso da epidemia. As condições ambientais foram mais favoráveis à doença em Arapoti, onde foi observado maior valor da AACPDp (38,2) e menos favoráveis para Castro (30,4).

The objective of this study was to evaluate the nutritional and productive performance of forage sorghum in an intercropping with soybean submitted to nitrogen doses. The experiment was in blocks with a complete randomized design, with four repetitions in a factorial arrangement (6x2+1), with six doses of nitrogen (0, 20, 40, 60, 80 e 100 kg de N ha-1), in two systems, being the intercropping of sorghum x soybean and one control with only sorghum with an application of 100 kg de N ha-1. The variables studied were sorghum dry and fresh matter productivity, crude protein of sorghum, fresh matter productivity for the intercropping and protein efficiency index. Higher doses of N applied as cover on the sorghum x soybean intercropping increased the quality and the productivity of the forage, when compared to the monoculture. The sorghum intercropping with two lines of soybean provides higher productivities of fresh matter, dry matter and crude protein. The intercropping with one and two lines of soybean provides a saving of 40% and 60%, respectively, of nitrogen on the production of crude protein when compared to monoculture. [ABSTRACT FROM AUTHOR]

The release of cultivars has ensured higher yield associated with increased tolerance to climatic adversity. ‘UFUSRiqueza’ is resistant to natural dehiscence and to the diseases: bacterial pustule, downy mildew, frogeye leaf spot, brown stem rot,stem canker and stem necrosis and can reach yields of 3475 kg ha-1, with grain contents of 18 % oil and 39 % protein.

A cultura da soja tem papel importante como matéria prima para o biodiesel e potencialidade para a produção de etanol a partir do carboidrato presente. Neste sentido, o presente trabalho teve como objetivo avaliar a divergência genética e a eficiência do uso do fósforo entre cultivares de soja, quanto ao teor de carboidratos, visando à produção de etanol. No ano agrícola 2009/10, foram realizados quatro ensaios de competição de cultivares de soja, sendo dois no Campus Universitário de Palmas e outros dois no Campus Universitário de Gurupi, totalizando quatro ambientes. Em cada local, os cultivares foram conduzidas sob alto e baixo fósforo (150 kg ha-1de P2O5 e 30 kg ha-1de P2O5 respectivamente). O delineamento experimental utilizado, em cada ensaio, foi de blocos casualisados com três repetições e 11 tratamentos: 1 (P98Y51), 2 (P98Y70), 3 (P99R01), 4 (P98R91), 5 (M9056RR), 6 (M 9144RR), 7 (M8766RR), 8 (M8867RR), 9(M8527RR), 10 (M9350), 11 (BR/EMGOPA 314)). Foi estudada a característica percentagem de carboidratos, sendo determinada a eficiência do uso de fósforo pelos cultivares, através da metodologia adaptada de Fischer, bem como realizada a estratificação ambiental. A divergência genética foi realizada através de procedimentos multivariados: distância generalizada de Mahalanobis e pelos métodos de agrupamento de Tocher e vizinho mais próximo. No estudo da divergência genética, cada ensaio representou uma variável distinta no modelo multivariado. Os cultivares apresentaram comportamento diferencial em função das doses de fósforo. Os ambientes foram dissimilares quanto à ordem de classificação dos cultivares. M8766RR, M8867RR e M9144RR são potencialmente promissores para produção de carboidratos e eficientes no uso do fósforo. As hibridações M8766RR x M9144RR e M8867RR X M9144RR são indicadas para obtenção de populações segregantes visando à produção de carboidratos.

Understanding the impact of Asian soybean rust on soybean yield is of great importance in the crop simulation model for this crop become it is possible to predict yield using different sowing dates and growth conditions. The goal of this study were to evaluate the performance of two soybean cultivars in Triângulo Mineiro/Alto Paranaíba, MG, Brazil and the effects of soybean rust on the yield of these cultivars using the CSM-CROPGRO Soybean model. Two soybean cultivars "NK 7074" (early) and "UFUS-Impacta" (medium late), which differ in their development cycles, were growing in Uberaba city during the 2009/2010 growing season. The validation for cultivar "UFUS-Impacta" was conducted comparing the measured and simulated yield data considering three different sowing dates in the "Uberlândia" city during the 2002/2003 growing season. Daily meteorological data obtained from six meteorological stations of the National Institute of Meteorology (INMET). To determine the performance of the soybean cultivars and the effect of soybean rust on yield, three different scenarios were used: no occurrence of rust (NOR) and occurrence of rust with inoculum concentrations of U5.000 and U10.000 urediniospores/mL. For all environments studied, the early cultivar had the best performance than the medium late cultivar. Soybean rust had the most effect on yield for the U10.000 scenario than for the U5.000 scenario. The best soybean performance occurred for "Araxá" and "Uberaba" cities. The South-Southeast area of the "Triângulo Mineiro/Alto Paranaíba" region was the most sensitive to the effect of rust on yield compared to the North region.

The influence of soybean moisture content-at-harvest and storage time upon total and non-hydratable phosphatides content in oil and bean phospholipase D activity was evaluated. Tests were performed upon soybeans harvested with moisture contents between 14.4 and 33.3% weight wet basis (wb). They were air dried at 25ºC until achieving safe storage moisture contents between 12.8 and 13.5 % wb and were stored at the same temperature for 245 days. Periodically they were analyzed for total and non-hydratable phosphatides content and phospholipase D activity. Total phosphatides initial content was high in soybeans with higher initial moisture levels and decreased slightly with time. Total phosphatides content remained constant at their initial levels in soybeans with lower initial moisture content. Non-hydratable phosphatides content was related to the phospholipase D activity, which decreased 30–35 days after harvest, and then stabilized, with values between 3.0 x 10-4 and 3.8 x 10-4 choline mmol/(min • soybean g).

Objetivando avaliar o efeito do número de aplicações foliares de fungicidas e da época de colheita de cultivares de soja, em duas épocas de semeadura, na qualidade fisiológica das sementes, foram conduzidos oito experimentos em duas etapas (campo e laboratório) na safra de 2003/04, em Viçosa-MG. Utilizou-se um esquema de parcelas subdivididas, tendo nas parcelas as aplicações dos fungicidas [mistura (Pyraclostrobin + Epoxiconazole) e Carbendazin] e nas subparcelas as épocas de colheita (R9, R9 + 15 e R9 + 30 dias). No delineamento em blocos casualizados com quatro repetições. Foram avaliadas a germinação, a emergência e o índice de velocidade de emergência. Concluiu-se que a germinação e a emergência de plântulas da cultivar Vencedora, colhidas no estádio R9, não foram influenciadas pelas aplicações de fungicidas e que o retardamento da colheita em 30 dias após o estádio R9 reduziu a germinação, a emergência de plântulas e o vigor das sementes, independentemente da cultivar e da época de semeadura.

Fungal species Fusarium solani and Pythium sp. are among the microorganisms causing diseases in pre and post harvest crop soybean (Glycine max). Four strains of the genus Bacillus (B. subtilis ATCC6633, B. amylolyticus, B. subtilis var. natto, B. subtilis var. natto domesticated) were tested to evaluate the inhibitory response of them on the phytopathogenic fungi previously mentioned. The inoculation treatments were 1) seeds inoculated with Bradyrhizobium japonicum, and 2) seeds coinoculated with B. japonicum and B. subtilis. Plants were grown in a thermostated culture chamber at 30±1 °C, 60 % relative humidity and 16/8 light-dark photoperiod for 35 d. Data were analyzed by ANOVA and means were compared by applying the Tukey test (p≤0.05). The in vitro assays of the strain B. subtilis ATCC6633 reduced the mycelial growth of Fusarium solani (50 %) and Pythium sp. (47 %) compared to controls. The coinoculation of B. japonicum and B. subtilis stimulated the growth of the whole plant by 125 %, 100 % aerial part, 235 % root, 20 % number of leaves, and 88 % nodule number compared to control. The strain B. subtilis ATCC6633 synthesized metabolites of proteinaceous nature and others with biosurfactant capacity. When the bacteria were grown in minimal saline medium, glycerol 1 % and concentrations of L-glutamic acid between 40 and 55 mM, the highest concentration of proteinaceous metabolites (35 μg protein mL-1) was obtained and increased biofilm formation. Biofilm formation, the presence of biosurfactants and the release of antifungal metabolites positioned this bacterium in a situation competitively advantageous compared to the rest of the microbiota of the rhizosphere in the soybean plant. [ABSTRACT FROM AUTHOR]

The objective of this study was to explore the potential interaction between gravity and growth hormones on isoflavonoid accumulation. Soybean callus ( Glycine max (L.) Merr. cv. 'Acme') was grown in the dark for 16 days at 22 °C in a growth medium supplemented with four different combinations of phytohormones and subjected to 4- g and 8- g forces simulated in a centrifuge and 1- g in an adjacent stationary control. Isoflavonoid aglycones and their glycoside concentrations (daidzein, genistein, daidzin, 6″-O-malonyl-7-O-glucosyl daidzein, genistin, 6″-O-malonyl-7-O-glucosyl genistein) were determined in the resulting tissues. Although gravity had no significant impact on callus growth, increasing gravity reduced isoflavonoid accumulation in three out of the four phytohormone-supplemented culture media. The ratio of the auxin naphthalene acetic acid (NAA) to the cytokinin benzylaminopurine (BAP) was found to have profound effect on both callus growth and isoflavonoid accumulation. The cytokinin BAP promoted callus tissue growth, but reduced callus isoflavonoid suggesting the isoflavonoid accumulation was not keeping pace with the cell growth in the elevated concentration of BAP. On the other hand, NAA had little or no effect on callus growth, but greatly enhanced isoflavonoid accumulation. Interactive effects of gravity and hormone on isoflavonoid accumulation were evident and its implication to the mechanism by which gravity exerts the effect on plant secondary metabolites is discussed. [ABSTRACT FROM AUTHOR]

Background and Aims Despite their toxicity, reactive oxygen species (ROS) play important roles in plant cell signalling pathways, such as mediating responses to stress or infection and in programmed cell death, at lower levels. Although studies have indicated that hydrogen peroxide (H2O2) promotes seed germination of several plants such as Arabidopsis, barley, wheat, rice and sunflower, the role of H2O2 in soybean seed germination is not well known. The aim of this study therefore was to investigate the relationships between ROS, plant hormones and soybean seed germination. Methods An examination was made of soybean seed germination, the expression of genes related to ethylene biosynthesis, endogenous ethylene contents, and the number and area of cells in the root tip, using N-acetylcysteine, an antioxidant, to counteract the effect of ROS. Key Results H2O2 promoted germination, which N-acetylcysteine suppressed, suggesting that ROS are involved in the regulation of soybean germination. H2O2 was produced in the embryonic axis after imbibition. N-Acetylcysteine suppressed the expression of genes related to ethylene biosynthesis and the production of endogenous ethylene. Interestingly, ethephon, which is converted to ethylene, and H2O2 reversed the suppression of seed germination by N-acetylcysteine. Furthermore, morphological analysis revealed that N-acetylcysteine suppressed cell elongation at the root tip, and this suppression was also reversed by ethephon or H2O2 treatments, as was the case in germination. Conclusions In soybean seeds, ROS produced in the embryonic axis after imbibition induce the production of endogenous ethylene, which promotes cell elongation in the root tip. This appears to be how ROS regulate soybean seed germination. [ABSTRACT FROM AUTHOR]

Vinte e seis cultivares de soja pertencentes ao grupo de maturação tardio foram avaliados com base em 85 locos RAPD, obtidos de 27 primers, submetendo-se os dados obtidos à técnica de bootstrap para determinar o número mínimo de locos necessários para se ter uma boa precisão nos estudos de diversidade genética. O procedimento de bootstrap dos locos foi utilizado para estimar o coeficiente de variação (CV) do índice de similaridade de Jaccard, utilizando-se 1000 permutações. O número mínimo de locos foi encontrado através da expressão xc= [ a2b2(2b-1)/(b-2)] 1/(2-2b) onde xc é o ponto de máxima curvatura da função, e corresponde à quantidade mínima de locos a ser amostrado no genoma. Foi obtido um coeficiente de determinação de 0,98, indicando um bom ajuste da curva estimada aos dados observados. Para este conjunto de dados, o ponto de curvatura máxima foi xc = 12,41, que corresponde a um CV de 33 %, e indica que o uso de 12 a 13 locos marcadores proporcionaria a precisão obtida para as estimativas. O parâmetro b da equação representa uma medida da heterogeneidade entre bandas. O valor encontrado neste estudo, de b = 0,426, mostra uma alta heterogeneidade entre bandas, já que o valor máximo esperado para este parâmetro é de 0,5. UNITERMOS: RAPD, Glycine max, diversidade genética