ABSTRACT Shade-tolerant soybean genotypes will allow their greater adoption for use in agroforestry or intercropped systems in tropical and subtropical regions. These genotypes can be obtained from the selection of existing superior genotypes or through breeding programs. This study, was verified such genetic variability and select those genotypes with cultivation potential at reduced levels of photosynthetically active radiation (PAR). Morphophysiological and yield characteristics of 16 soybean genotypes were evaluated in two experiments conducted in a controlled environment and laid in a randomized block design with three replications. Genetic parameters, correlations and genetic diversity were estimated and path analysis was performed. The soybean cultivars used showed genetic variability with a high variation index and heritability, which is advantageous for the selection of superior cultivars. Leaf area showed genotypic correlation and had a direct effect on seed weight per plant, regardless of shading. Additionally, the number of pods, hypocotyl diameter, and leaf area, all indirectly contributed to seed weight per plant regardless of shading. Seven genotypes (NS7780, NS8338, NS7667, NS7901, RK8115, CZ37B43 and 8579RSF) were selected based on genetic gain obtained by the Mulamba and Mock index at the two levels of PAR reduction tested. Furthermore, five of these genotypes (CZ37B43, RK8115, NS7901, NS8338 and 8579RSF) were identified by the Unweighted Pair-Group method Arithmetic Mean, as suitable either as a shaded crop or, as parental materials in breeding programs. Shadetolerant Shade tolerant regions programs study PAR. . (PAR) 1 replications parameters performed heritability shading Additionally pods diameter NS7780, NS7780 NS (NS7780 NS7667 NS7901 RK8115 RK CZB CZ B CZ37B4 8579RSF RSF tested Furthermore CZ37B43, (CZ37B43 NS833 PairGroup Pair Group Mean (PAR NS778 (NS778 NS766 NS790 RK811 CZ37B (CZ37B4 NS83 NS77 (NS77 NS76 NS79 RK81 (CZ37B NS8 NS7 (NS7 RK8 (NS

Abstract The aim of this study was to identify, through different methodologies, soybean cultivars with adaptability and stability for grain yield in environments with different levels of light restriction. The grain yield of sixteen cultivars was evaluated in environments with 25% and 48% restriction of photosynthetically active radiation (PAR) in the agricultural years 2019/2020 and 2021/2022. Based on the results, an adaptability and stability analysis was performed using the Eberhart and Russell, ANN (Artificial Neural Network) and GGE (Genotype plus Genotype-Environment interaction) methods. Grain yield varied with the levels of PAR restriction and agricultural years, being higher in environments A3 (2021/2022 25% PAR) and A1 (2019/2020 25% PAR), respectively. Cultivars NS7780, 8579RSF, NS8338 and RK6718 showed higher yield. The adaptability of cultivars AS3680, M7110, and 74177RSF was low, while that of NS8338 and NS7780 was high. Cultivars NS8338, 74177RSF, RK7518, and M6210 showed high phenotypic stability to environments. identify methodologies 25 48 (PAR 20192020 2019 2020 2019/202 20212022 2021 2022 2021/2022 results Russell Artificial Network Genotype GenotypeEnvironment Environment interaction methods A (2021/202 (2019/202 PAR, , respectively NS 8579RSF RSF NS833 RK RK671 AS3680 AS M7110 M low NS778 RK7518 M621 2 4 2019202 201 202 2019/20 2021202 2021/202 (2021/20 (2019/20 NS83 RK67 AS368 M711 NS77 RK751 M62 201920 20 2019/2 202120 2021/20 (2021/2 (2019/2 NS8 RK6 AS36 M71 NS7 RK75 M6 20192 2019/ 20212 2021/2 (2021/ (2019/ AS3 M7 RK7 2021/ (2021 (2019 (202 (201 (20 (2 (

RESUMO: O comprimento do hipocótilo tem-se destacado como potencial descritor da cultura da soja, no entanto, não se tem informação sobre o seu comportamento ao longo de várias épocas de plantio. Diante disto, objetivou-se identificar cultivares de soja com estabilidade e previsibilidade de comportamento quanto ao comprimento do hipocótilo por meio de redes neurais e metodologias tradicionais de adaptabilidade e estabilidade. Analisou-se 16 cultivares de soja em seis épocas de plantio, em condições de casa de vegetação. Em cada época, adotou-se o delineamento em blocos casualizados com quatro repetições, sendo a unidade experimental composta por três plantas e usou-se a média da parcela na análise. Os dados de comprimento de hipocótilo foram analisados por meio da análise de variância e teste de Tukey e, posteriormente, procedeu-se análises por meio do Método Tradicional, Plaisted e Peterson, Wricke, Eberhart e Russell e Redes Neurais Artificiais. Identificou-se efeito significativo (p<0,01 pelo teste F) para Cultivares x Épocas, Épocas e Cultivares. As cultivares BRS810C, BRSMG760SRR, TMG1175RR e BMX Tornado RR apresentaram menores médias, alta estabilidade e adaptabilidade geral quanto ao comprimento do hipocótilo de soja; enquanto que, a cultivar BG4272 apresentou maior média, alta estabilidade e adaptabilidade geral. A identificação de cultivares de soja de comportamento previsível e estável, quanto ao comprimento do hipocótilo, contribui para o Melhoramento da Soja no tocante ao melhor conhecimento do potencial descritor e à possibilidade de incremento do número de descritores.

ABSTRACT: The length of the hypocotyl has been highlighted as a potential descriptor of the soybean crop. However, there is no information available in the published literature about its behavior over several planting times. The present study aimed to identify soybean cultivars with stability and predictability of hypocotyl length behavior through neural networks and traditional adaptability and stability methodologies. We analyzed 16 soybean cultivars in 6 planting seasons under greenhouse conditions. In each season, a randomized block design with 4 replications was adopted. The experimental unit was composed of 3 plants. The plot mean was used in the analysis. Hypocotyl length data were analyzed by analysis of variance and Tukey’s test. Then analyses were carried out using the Traditional Method, Plaisted and Peterson, Wricke, Eberhart and Russell, and Artificial Neural Networks. A significant effect (p<0.01 by the F test) was identified for Cultivars versus Planting Season and Planting Seasons and Cultivars. Cultivars BRS810C, BRSMG760SRR, TMG1175RR, and BMX Tornado RR showed lower averages, high stability, and general adaptability regarding soybean hypocotyl length whereas the cultivar BG4272 presented higher mean, high stability, and general adaptability. Identification of soybean cultivars of predictable and stable behavior as to hypocotyl length contributes to Soybean Improvement as it further our knowledge on the potential descriptor and the possibility of increasing the number of descriptors.

Objetivou-se analisar a herança e identificar marcadores microssatélites ligados ao gene de resistência da 'TMG 803' à Phakopsora pachyrhizi. Foi realizada hibridação entre as cultivares TMG 803 e BRS Valiosa RR para obtenção da progênie F1 e população F2. Os genitores 'TMG 803' e 'BRS Valiosa RR' comportaram-se, respectivamente, como resistentes e suscetíveis e entre as 116 plantas F2, 93 comportaram-se como resistentes e 23 como suscetíveis à P. pachyrhizi, submetidas à infecção natural, em condições de campo. Verificou-se que a resistência da cultivar TMG 803 é governada por um gene com dominância completa, mapeado como o loco de resistência Rpp4, do grupo de ligação G. Dentre os 16 marcadores microssatélites testados, um marcador, sc21_3420, encontrou-se completamente ligado ao gene de resistência (distância de 0,0cM) estando a forma alélica favorável presente na cultivar TMG 803, podendo, portanto, ser útil na seleção assistida em populações segregantes.

This study analyzed the inheritance and identified microsatellite markers linked to the resistance gene to Phakopsora pachyrhizi in soybean cultivar TMG 803. Hybridization between the cultivars TMG 803 and BRS Valiosa RR was performed to obtain F1 progenies and the F2 population. The response of the parents 'TMG 803' and 'BRS Valiosa RR' to P. pachyrhizi was, respectively, resistant and susceptible, and among the 116 F2 plants,93 were resistant and 23 susceptible, under natural infection and field conditions. It was found that the resistance of cultivar TMG 803 is controlled by one gene with complete dominance, mapped as resistance locus Rpp4 of linkage group G. Of the 16 tested, one microsatellite marker, sc21_3420, was completely linked to the resistance gene (distance 0.0cM) and the favorable allelic form was present in cultivar TMG 803, which may therefore be useful in assisted selection in segregating populations.

Objetivou-se estimar parâmetros genéticos e o tamanho ótimo das amostras para comprimento do hipocótilo e do epicótilo, e analisar a conversão dos dados quantitativos em multicategóricos para genótipos de soja. Foram analisados 85 genótipos de soja em quatro experimentos no delineamento inteiramente casualizado, em condições de casa de vegetação da Universidade Federal de Viçosa. A magnitude das estimativas dos parâmetros genéticos caracterizou a influência de componentes genéticos na expressão fenotípica do comprimento do hipocótilo e do epicótilo em genótipos de soja; o tamanho ótimo da amostra variou entre genótipos avaliados; e a conversão dos dados quantitativos em multicategóricos proporcionou estimativas de coeficientes de correlação maior que 0,80 e de coincidência maior que 81% entre os dados convertidos e os originais.

The objective of this study was to estimate the genetic parameters and optimal sample size for the lengths of the hypocotyl and epicotyls and to analyze the conversion of quantitative data in multiple categories for soybean genotypes. A total of 85 soybean genotypes were analyzed in four experiments in a completely randomized design under greenhouse conditions at the Federal University of Viçosa, Brazil. The magnitude of the genetic parameter estimates characterized the influence of the genetic components in the phenotypic expression of the length of the hypocotyls and epicotyls of different soybean genotypes. The optimal size of the sample varied between the genotypes and the conversion of the quantitative data in multiple categories provided estimates of correlation coefficients greater than 0.80 and coincidence greater than 81% between the converted data and the original data.

The development of soybean cyst nematode, Heterodera glycines Ichinohe, resistant genotypes with high yields has been one of the objectives of soybean (Glycine max (L.) Merrill) breeding programs. The objective of this study was to characterize the pathotype of soybean cyst nematodes and analyze the genetic diversity of ten differentiator lines ('Lee 74', Peking, Pickett, PI 88788, PI 90763, PI 437654, PI 209332, PI 89772, PI 548316 and 'Hartwig'). Inoculum was obtained from plants cultivated in field soil in Viçosa, state of Minas Gerais, Brazil. Thirty-four days after inoculating each plant with 4,000 eggs, the number of females, female index, total number of eggs, number of eggs per female, reproduction factor, plant height, number of nodes, fresh and dry matter weights were assessed. The differential lines were first grouped with Scott-Knott test. Subsequently, the genetic diversity was evaluated using dendrograms, graphic analysis and the Tocher grouping method. The inoculum of H. glycines obtained from NBSGBP-UFV was characterized as HG Type 0. The differentiating lines were divergent, and PI 89772, PI 437654, 'Hartwig' and 'Peking' had the greatest potential for use in breeding programs.

Estudos envolvendo descritores adicionais têm sido de importância para o melhoramento genético de soja. Por isso, neste trabalho, objetivou-se estimar o coeficiente de repetibilidade do comprimento do hipocótilo, do epicótilo, do internódio entre o nó das folhas unifolioladas e da primeira folha trifoliolada, do pecíolo e da raque da primeira folha trifoliolada e determinar o número mínimo de avaliações necessário para predizer o valor real dos genótipos. O trabalho foi desenvolvido na Universidade Federal de Viçosa, analisando-se 85 genótipos de soja em quatro experimentos, no delineamento inteiramente casualizado. A partir das estimativas dos coeficientes de repetibilidade e de determinação obtidos pelos métodos - da análise de variância, dos componentes principais e da análise estrutural -, foram calculados os números de avaliações necessárias. Concluiu-se que os comprimentos do hipocótilo, do epicótilo e do internódio requereram menor quantidade de medição em comparação com os comprimentos do pecíolo e da raque, para o mesmo nível de confiabilidade; e com 15 medições obteve-se 85% de confiabilidade para comprimento do hipocótilo pelos métodos ANOVA e AE(correl) e 90% para CP(correl) e CP(cov); 90% de confiabilidade para comprimento do epicótilo e do internódio pelos métodos ANOVA, CP(correl), CP(cov) e AE(correl); 80% de confiabilidade para comprimento da raque da primeira folha trifoliolada pelos métodos ANOVA, CP(correl), CP(cov) e AE(correl); e, para o comprimento do pecíolo da primeira folha trifoliolada, seriam necessárias 21 medições para confiabilidade de 80% pelos métodos ANOVA e AE(correl) e de 85% pelos CP(correl) e CP(cov).

Studies involving additional descriptors has been important for soybean genetic improvement, so this study aimed to estimate the repeatability the length coefficient of hypocotyl, epicotyl, the internode between the unifoliated leaf nodes and the first trifoliate leaf, from the petiole and from the rachis of the first trifoliate leaf stage and determine the minimum number of evaluations needed to predict the real value of the genotypes. The study was conducted at the Universidade Federal de Viçosa, analyzing 85 soybean genotypes in four experiments in a completely randomized design. The numbers of necessary evaluations were calculated from the estimates of repeatability and coefficient of determination obtained by the methods of analysis of variance of the principal component and by the structural analysis. It was concluded that the lengths of the hypocotyl, epicotyl and the internode required fewer measurements compared with the length of the petiole and rachis to the same level of reliability, and with 15 measurements 85% of reliability was obtained for hypocotyl length by ANOVA and AE(correl) methods and 90% by CP(correl) and CP(cov) methods; 90% reliability was obtained for epicotyl and internode length by ANOVA, CP(correl), CP(cov) and AE(correl) method; 80% reliability was obtained for rachis length by ANOVA, CP(correl), CP(cov) and AE(correl) methods; and for petiole length, 21 measurements were needed for reliability by ANOVA and AE(correl) methods and 85% for CP(correl) and CP(cov) methods.

Heterodera glycines é um fitonematoide de importância econômica para a cultura da soja. Por isso, objetivou-se comparar metodologias para a avaliação de genótipos de soja em relação a este nematoide. Foram desenvolvidos dois experimentos (Ensaios A e B), em casa de vegetação, em delineamento inteiramente casualizado com seis repetições. No ensaio A, utilizaram-se vasos de cerâmica de 0,8 dm³ e métodos-padrão de inoculação e avaliação. No ensaio B, utilizaram-se vasos de polietileno de 0,5 dm³ preenchidos com solo infestado e análise visual. Foram avaliados genótipos promissores de diferentes programas de melhoramento genético de soja. Dos genótipos analisados, em 74% havia número de fêmeas semelhantes em ambos os ensaios. O coeficiente de correlação entre o número de fêmeas do Ensaio A e o número de fêmeas do Ensaio B foi de 0,85 (p<0,01) e entre o número de fêmeas do Ensaio A e a nota visual do número de fêmeas Ensaio B foi 0,90 (p<0,01). Os métodos-padrão de inoculação e avaliação utilizando solo infestado e análise visual foram, de maneira geral, coerentes entre si. Foram identificados genótipos resistentes (UFVS 2010 e BCR1070G229) e moderadamente resistentes (BCR132390, BCR945G114 e BCR1057G163) ao nematoide de cisto raça 3, pelos dois métodos de avaliação.

Heterodera glycines is a phytonematode of economic importance in the soybean crop. Therefore, the objective was to compare methodologies for evaluation of soybean genotypes in relation to H. glycines. Two experiments were conducted (trials A and B) under greenhouse condition in a completely randomized design with six replications. In the trial A, ceramic pots of 0.8 dm³ and standard methodologies of inoculation and assessment were used. In the trial B, polyethylene pots filled with 0.5 dm³ infested soil and visual analysis were used. Promising genotypes obtained by different soybean genetic breeding programs were evaluated. Seventy four percent of the studied genotypes presented similar numbers of females in both trials. The correlation coefficient between the number of female in trial A and the number of female in trial B was 0.85 (p<0.01) and between the number of female in trial A and the visual rating of the number of females in trial B was 0.90 (p<0.01). The standard methodologies of inoculation and evaluation using infested soil and visual analysis were, in general, mutually consistent. Genotypes identified as resistant (UFVS 2010 and BCR1070G229) and moderately resistant (BCR132390, BCR945G114 and BCR1057G163) to the cyst nematode race 3 were found by the two methods of assessment.

Este trabalho teve como objetivo analisar a diversidade genética entre genótipos de soja inoculados com Heterodera glycines, raça 3. Os experimentos foram conduzidos sob condições de casa de vegetação. Foram avaliados 27 genótipos de soja sob dois ensaios de análise do comportamento quanto às características morfoagronomicas e de resistência ao patógeno. Estimou-se o coeficiente de determinação genotípica, a partir do método da análise de variância, e análise de diversidade genética por meio de dendrogramas e método de otimização. Verificou-se que as estimativas dos coeficientes de determinação genotípica demonstraram que as diferenças observadas nos caracteres avaliados foram de natureza, predominantemente, genética; e os genótipos superiores mantiveram a variabilidade genética, podendo ser utilizados em programas de melhoramento para resistência a nematoide de cistos.

The purpose of this study was to analyze the genetic diversity among soybean genotypes inoculated with Heterodera glycines race 3. The experiments were conducted in a greenhouse. In two performance tests of morphological characteristics and resistance to the pathogen, 27 soybean genotypes were assessed. The coefficient of genotypic determination was estimated by the method of analysis of variance and the genetic diversity analyzed based on dendrograms and optimization method. The estimated coefficients of determination indicated a predominantly genetic origin of the genotypic differences in the traits. The genetic variability was maintained in the superior genotypes, which can be used in breeding programs for resistance to soybean cyst nematode.

Avaliaram-se a estabilidade e a previsibilidade da qualidade fisiológica de sementes de 13 genótipos de soja [Glycine max (L.) Merrill], produzidas em três localidades do município de Cristalina, Estado de Goiás. Os ensaios de melhoramento foram conduzidos no campo no ano agrícola 2004/05. Os ensaios de avaliação da qualidade das sementes foram realizados nos laboratórios e casa-de-vegetação da Universidade Federal de Viçosa, instalados no delineamento inteiramente casualizado com quatro repetições. Foram realizados os testes de germinação em papel toalha, emergência em leito de areia, índice de velocidade de emergência e análises de estabilidade pelos métodos propostos por Lin e Binns (1988) e Annicchiarico (1992). As médias de porcentagem de germinação, emergência de plântulas e índice de velocidade de germinação foram comparadas pelo teste de Tukey, a 5% de probabilidade. Na avaliação da qualidade fisiológica de sementes, foi identificado, como melhor, o genótipo 7B1454170 e como pior, o genótipo 9B1459189. Os genótipos Emgopa 313, 7B1454170, 11B145341 e DM339 foram classificados como de alta estabilidade para qualidade fisiológica, e os genótipos 3B1346193 e 9B1459189 classificaram-se como de baixa previsibilidade. Os métodos de estimação utilizados foram eficazes, coerentes entre si e permitiram identificar, entre os genótipos avaliados, os de maior estabilidade e previsibilidade.

The physiological quality stability and predictability of seeds from 13 soybean genotypes [Glycine max (L.) Merrill] were analyzed. They were produced at three different locations in the town of Cristalina, Goiás. The field improvement trials were held in the agricultural year of 2004/05. The seed quality evaluation studies took place in the laboratories and in the greenhouse of the Federal University of Viçosa, in a completely randomized design with four repetitions. Germination in paper towels, emergence in sand bed, index of emergence speed and stability analyses were tested through the methods proposed by Lin and Binns (1988) and Annicchiarico (1992). The germination percentage averages, the emergence of plants and the emergence speed index were compared through Tukey's test at 5% probability. In the evaluation of the seeds' physiological quality, genotype 7B1454170 was identified as the best, and genotype 9B1459189 as the worst. The genotypes Emgopa 313, 7B1454170, 11B145341 and DM339 were classified as offering high stability in physiological quality, and genotypes 3B1346193 and 9B1459189 offered low predictability. The estimation methods used were efficient, coherent among them and allowed the identification, among the evaluated genotypes, of the ones that offered greater stability and predictability.