RESUMO: Este trabalho teve como objetivo avaliar a importância da análise de variância (ANOVA) geral preliminar na interpretação dos dados de experimentos fatoriais sob nulidade total. Para isso, avaliou-se as taxas de erro tipo I familiar (FWER acumulada) do teste F para os componentes do desdobramento da ANOVA fatorial e da ANOVA fatorial on ranks, em comparação à FWER para o efeito global de tratamentos. Além disso, avaliou-se a FWER do teste de Tukey sob nulidade total para experimentos fatoriais na presença ou ausência da proteção da ANOVA preliminar (teste F global). O estudo foi conduzido a partir da simulação de dados de 2000 experimentos, separados em quatro cenários representativos da pesquisa agrícola. Tanto para a ANOVA fatorial paramétrica, quanto para a ANOVA fatorial não-paramétrica, as FWER ultrapassaram significativamente o nível nominal de 5%, mesmo sob nulidade total. Enquanto os testes que controlam a FWER total nos fatoriais não estiverem sendo utilizados, a ANOVA fatorial não deve ser realizada sem que o teste F da ANOVA preliminar acuse um efeito significativo. O mesmo, evidentemente, não se aplica aos testes que não são de comparações múltiplas, como Bonferroni, Dunn-Sidak e outros, que não precisam proteção da ANOVA. A mesma recomendação se aplica à ANOVA fatorial on ranks.

ABSTRACT: This research evaluated the importance of a preliminary general analysis of variance (ANOVA) in the interpretation of data from factorial experiments under total nullity. For this, we evaluated the familywise type I error rate (accumulated FWER) of the F test for the unfolding of factorial ANOVA and factorial ANOVA on ranks, which were compared with the FWER for the global effect of treatments. In addition, we evaluated the FWER of the Tukey’s test under total nullity for factorial experiments in the presence or absence of preliminary ANOVA protection (omnibus F test). The study was conducted by simulating data from 2,000 experiments, which were separated into four representative agricultural research scenarios. For both the parametric factorial ANOVA and the non-parametric factorial ANOVA, the FWER significantly exceeded the nominal level of 5%, even under total nullity. While the tests that control the total FWER in the factorials are not being used, the factorial ANOVA should not be performed without the preliminary ANOVA F test showing a significant effect. This, of course, does not apply to tests that are not multiple comparisons, such as Bonferroni, Dunn-Sidak and others, which do not need ANOVA protection. The same recommendation applies to the factorial ANOVA on ranks.

Abstract Amongst the sustainable alternatives to increase maize production is the use of plant growth-promoting bacteria (PGPB). Azospirillum brasilense is one of the most well-known PGPB being able to fix nitrogen and produce phytohormones, especially indole-3-acetic acid - IAA. This work investigated if there is any contribution of the bacterium to the plant’s IAA levels, and how it affects the plant. To inhibit plant IAA production, yucasin, an inhibitor of the TAM/YUC pathway, was applied. Plantlets’ IAA concentration was evaluated through HPLC and dual RNA-Seq was used to analyze gene expression. Statistical differences between the group treated with yucasin and the other groups showed that A. brasilense inoculation was able to prevent the phenotype caused by yucasin concerning the number of lateral roots. Genes involved in the auxin and ABA response pathways, auxin efflux transport, and the cell cycle were regulated by the presence of the bacterium, yucasin, or both. Genes involved in the response to biotic/abiotic stress, plant disease resistance, and a D-type cellulose synthase changed their expression pattern among two sets of comparisons in which A. brasilense acted as treatment. The results suggest that A. brasilense interferes with the expression of many maize genes through an IAA-independent pathway.

Resumo Este estudo de caso, de natureza aplicada com abordagem qualitativa-descritiva, tem por objetivo mostrar a importância de projetos de transferência de tecnologia (TT) na agricultura, em especial o projeto da Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA), denominado Reniva – rede de multiplicação e transferência de materiais propagativos de mandioca com qualidade genética e fitossanitária. A mandioca é um tubérculo, rico em carboidratos, de grande importância econômica e social no nosso país e no mundo. Sua cadeia produtiva é uma das mais importantes na agricultura familiar, emprega mais de 1 milhão de pessoas e movimenta algo em torno de 10 bilhões de reais por ano no Brasil. Porém sofre muitas perdas com doenças e baixa produtividade. O Projeto Reniva contribui para o desenvolvimento e aperfeiçoamento do cultivo da mandioca, por meio do melhoramento genético, da seleção de variedades mais produtivas e resistentes, da transferência de tecnologia entre entidades de Pesquisa, Desenvolvimento e Inovação (PD&I) e agricultores, inovação de processos e transferência de know-how para utilização dessas novas tecnologias, tendo por resultado adoção de novas práticas, mão de obra mais qualificada e a disponibilização de mudas, “manivas-sementes”, geneticamente resistentes às doenças, com maior produtividade e adaptadas às diversas localidades. Muito está sendo feito, porém é preciso verificar os resultados e garantir a continuidade do projeto após o primeiro ciclo.

Abstract This case study, of applied nature with a qualitative-descriptive approach, aims to show the importance of technology transfer (TT) projects in agriculture, especially the Brazilian Agricultural Research Corporation’s (EMPRAPA) project called Reniva – a network for the multiplication and transfer of propagating materials of genetic and phytosanitary quality. Cassava is a carbohydrate-rich tuber of great economic and social importance in our country and around the world. Its productive chain is one of the most important in family farming, employs more than 1 million people, and moves around R$ 10 billion a year in Brazil. However, it suffers many losses due to pests and low productivity. The Reniva Project contributes to the development and improvement of cassava cultivation through genetic improvement, selection of more productive and resistant varieties, technology transfer between Research, Development, and Innovation (RD&I) entities and farmers, process innovation, and know-how transfer to use these new technologies, resulting in more qualified manpower, adoption of new practices, availability of genetically resistant seedlings, “maniva-seed”, with higher productivity and adapted to different locations. Much is being done, but it’s necessary to verify the results and ensure the continuity of the project after the first cycle.

Resumen Este estudio de caso, de carácter aplicado con enfoque cualitativo-descriptivo, tiene como objetivo mostrar la importancia de los proyectos de transferencia de tecnología (TT) en la agricultura, en especial al proyecto de la Empresa Brasileña de Pesquisa Agropecuaria (EMBRAPA), denominado Reniva – red de multiplicación y transferencia de materiales propagantes de mandioca con calidad genética y fitosanitaria. La mandioca es un tubérculo, rico en carbohidratos, de gran importancia económica y social en nuestro país y en el mundo. Su cadena productiva es una de las más importantes en la agricultura familiar, emplea a más de 1 millón de personas y mueve aproximadamente a 10 billones de reales al año en Brasil. Sin embargo, sufre muchas pérdidas por las plagas y la baja productividad. El Proyecto Reniva colabora para el desarrollo y mejora del cultivo de la mandioca, a través de la mejora genética, selección de variedades más productivas y resistentes, por medio de la transferencia de tecnología entre entidades de Investigación, Desarrollo e Innovación (I+D+I) y agricultores, innovación de procesos y transferencia de know-how para utilización de estas nuevas tecnologías, teniendo como resultado adopción de nuevas prácticas, mano de obra más calificada y la disponibilidad de mudas, “manivas-semillas”, genéticamente resistentes a enfermedades, con mayor productividad y adaptadas a diferentes ubicaciones. Mucho se está haciendo, pero es necesario averiguar los resultados y garantizar la continuidad del proyecto después del primer ciclo.

Resumo A glutamina sintetase (GS), codificada por glnA, catalisa a conversão de L-glutamato e amônio em L-glutamina. Este processo dependente da hidrólise de ATP é a principal via de assimilação de nitrogênio na bactéria fixadora de nitrogênio Azospirillum brasilense. A estirpe HM053 de A. brasilense possui baixa atividade GS e excreta amônio no meio sob condições de fixação de nitrogênio. Neste trabalho, os genes glnA das estirpes do tipo selvagem e HM053 foram clonados em pET28a, sequenciados e superexpressos em E. coli. A enzima GS foi purificada por cromatografia de afinidade e caracterizada. A GS da estirpe HM053 possui uma substituição P347L que resulta em baixa atividade enzimática e torna a enzima insensível à adenililação pela adenililtransferase GlnE.

Abstract Glutamine synthetase (GS), encoded by glnA, catalyzes the conversion of L-glutamate and ammonium to L-glutamine. This ATP hydrolysis driven process is the main nitrogen assimilation pathway in the nitrogen-fixing bacterium Azospirillum brasilense. The A. brasilense strain HM053 has poor GS activity and leaks ammonium into the medium under nitrogen fixing conditions. In this work, the glnA genes of the wild type and HM053 strains were cloned into pET28a, sequenced and overexpressed in E. coli. The GS enzyme was purified by affinity chromatography and characterized. The GS of HM053 strain carries a P347L substitution, which results in low enzyme activity and rendered the enzyme insensitive to adenylylation by the adenilyltransferase GlnE.

RESUMO Os sistemas agroflorestais (SAFs) integram, com práticas sustentáveis, culturas agrícolas e florestais para produção de madeira e alimentos, conservando os serviços ambientais e a biodiversidade. O freijó, Cordia goeldiana, tem potencial para cultivo na Amazônia para fins madeireiros, porém dados sobre as características de sua madeira em SAFs são escassas. Objetivou-se determinar as propriedades físico-mecânicas e aplicações tecnológicas da madeira de freijó produzida em um SAF multiestratificado estabelecido no estado de Rondônia, Brasil em 1996. No SAF, as espécies agrícolas e madeireiras foram estabelecidas em renques duplos no espaçamento 5,0 m x 2,5 m. Abateram-se três árvores de freijó com 19 anos de idade, para caracterização química, física (densidade e estabilidade dimensional) e mecânica (compressão, flexão estática, dureza Janka e cisalhamento) da madeira. A madeira de freijó apresentou composição química similar à de madeiras nobres tropicais, peso moderado (582,63 kg m-3) e estabilidade dimensional elevada em comparação com outras madeiras consagradas no mercado (retração longitudinal, radial e tangencial = 0,25, 4,27 e 6,83%, respectivamente). Os valores de resistência à compressão paralela (32,32 MPa) e perpendicular (8.02 MPa), resistência específica (55,32 MPa kg-1 m-3), dureza Janka paralela (2373,33 N) e perpendicular (2326,67 N), resistência à flexão estática (63,5 MPa) e ao cisalhamento (5,94 MPa) foram semelhantes aos valores observados em outras madeiras tropicais de alta densidade, produzidas em monocultivo e florestas naturais. A madeira em estudo é adequada para fabricação de produtos de alto valor agregado, como móveis finos, pisos residenciais, instrumentos musicais e peças estruturais.

ABSTRACT Agroforestry systems (AFSs) integrate, through sustainable practices, agricultural and forest crops for the production of wood and food, providing environmental services, and conserving biodiversity. The freijó (Cordia goeldiana) has potential for cultivation in the Amazon for timber purposes, but data on the characteristics of its wood produced in AFSs are scarce. Our objective was to determine the physical-mechanical properties and suggest technological applications of freijó wood produced in a multi-stratified AFS established in the state of Rondônia, Brazil in 1996. Agricultural and forest species were established in the AFS in double rows with 5.0-m x 2.5-m spacing. Three 19-year-old freijó trees were harvested for chemical, physical (density and dimensional stability), and mechanical (compression, static bending, Janka hardness, and shear strength) characterization of the wood. The wood presented a chemical composition similar to tropical hardwoods, was moderately heavy (582.63 kg m-3), and had high dimensional stability in comparison with other consecrated woods on the market (longitudinal, radial, and tangential retraction = 0.25, 4.27, and 6.83%, respectively). The values determined for parallel (32.32 MPa) and perpendicular compression (8.02 MPa), specific strength (55.32 MPa kg-1 m-3), parallel (2373.33 N) and perpendicular Janka hardness (2326.67 N), strength to static bending (63.5 MPa), and shear (5.94 MPa) were similar to the values observed in other high-density tropical woods grown in either monoculture plantations or natural forests. The wood under study is suitable for manufacture of high-value-added products, such as fine furniture, residential floors, musical instruments and structural pieces.

Abstract Butia eriospatha is an endemic palm species from the Atlantic Rainforest in Brazil, a biodiversity hotspot. This species is currently listed in the IUCN red list as vulnerable and lacks specific plastid markers for population genetics studies. In addition, the evolutionary relationship within the genus Butia is not yet well resolved. Here, we sequenced and characterized the complete plastid genome (plastome) sequence of B. eriospatha. The complete plastome sequence is 154,048 bp in length, with the typical quadripartite structure. This plastome length and genes content is consistent with other six species from tribe Cocoseae. However, the Inverted Repeat (IR) borders show some variation among the analyzed species from this tribe. Species from the Bactridinae (Astrocaryum and Acrocomia) and Elaeidinae (Elaeis) subtribes present the rps19 gene completely duplicated in the IR region. In contrast, all plastomes sequenced from the subtribe Attaleinae (Butia, Cocos, Syagrus) present one complete CDS of rps19 and one partial copy of rps19. The difference in the IR/LSC junctions between Attaleinae and the sister clades Bactridinae + Elaeidinae might be considered an evolutionary signal and the plastome sequence of B. eriopatha may be used in future studies of population genetics and phylogeny.

RESUMO: Herbaspirillum seropedicae é uma bactéria fixadora de nitrogênio, capaz de utilizar compostos tóxicos como fonte de carbono. Bactérias com essa capacidade podem ser utilizadas para tornar os animais resistentes à intoxicação por plantas que contém monofluoroacetato (MFA), como Amorimia septentrionalis. O objetivo do presente estudo é avaliar se H. seropedicae é eficiente na degradação do MFA presente em A. septentrionalis e se a inoculação dessa bactéria, em caprinos, confere proteção à intoxicação por A. septentrionalis. Foram realizados dois experimentos: no primeiro experimento foram utilizados 12 caprinos, divididos em dois grupos. Os caprinos do Grupo 1 receberam diariamente, oralmente, uma solução contendo a bactéria H. seropedicae durante 10 dias. A partir do décimo dia passaram a receber, diariamente, além da solução com a bactéria 5g/kg de A. septentrionalis até a observação de sinal clínico de intoxicação. Os caprinos do Grupo 2 receberam apenas a planta na mesma dose, também até que a observação de sinais clínicos de intoxicação. A quantidade de MFA encontrada em A. septentrionalis utilizada no experimento com caprinos foi de 1,6± 0,058µg/mg de planta em média. A dose total de planta ingerida por todos os caprinos do Grupo 1 foi de 80,83±12,81g/kg (129,33±20,50mg/kg de MFA), valores significativamente maiores (p<0,05) do que os dos caprinos do Grupo 2 (39,16±19,08g/kg de planta e 62,66± 30,53mg/Kg de MFA). Os caprinos do Grupo 1 demoraram em média 16,16 ±2,56 dias para desenvolver sinais clínicos da intoxicação, período significativamente maior (p=0,0012) que os caprinos do Grupo 2 (7,83±3,81dias). Dois caprinos do Grupo 2 morreram no mesmo dia que desenvolveram sinais clínicos da intoxicação. Na necropsia desses dois animais não foram observadas alterações significativas. No segundo experimento, amostras de A. septentrionalis foram pulverizadas com uma solução contendo a bactéria H. seropedicae. Antes e oito dias após a pulverização, as amostras foram prensadas e secas para posterior quantificação do MFA. A quantidade de MFA presente nas amostras de A. septentrionalis oito dias após a pulverização com H. seropedicae foi significativamente menor (p=0,017) do que a encontrada antes da pulverização. Pode-se concluir que a administração de H. seropedicae em caprinos é capaz de causar uma maior resistência à intoxicação por A. septentrionalis, e a pulverização da planta com esta bactéria reduz significativamente a quantidade de MFA na planta.

ABSTRACT: Herbaspirillum seropedicae is a nitrogen-fixing bacterium capable of using toxic compounds as a source of carbon. Bacteria with this capacity can be used to make animals resistant to plant poisoning containing monofluoroacetate (MFA), such as Amorimia septentrionalis. The aim of this study was to evaluate if H. seropedicae is efficient in the degradation of MFA present in A. septentrionalis and if the inoculation of this bacterium in goats confers protection to A. septentrionalis intoxication. Two experiments were performed: in the first experiment 12 goats were divided into 2 groups. Goats in Group 1 were orally administered a solution containing the H. seropedicae bacterium for 10 days. From day 10 onwards, they received a daily dose of 5g/kg of A. septentrionalis with the bacteriauntil clinical signs of intoxication were observed. Group 2 goats received only the plant at the same dose, also until the observation of clinical signs of intoxication. The amount of MFA found in A. septentrionalis used in the experiment with goats was 1.6±0.058μg/mg. The total plant dose ingested by all goats in Group 1 was 80.83±12.81g/kg (129.33±20.50mg/kg MFA), which were significantly greater (p<0.05) than those of Group 2 goats (39.16±19.08g/kg plant and 62.66±30.53mg/kg MFA). Group 1 goats took an average of 16.16±2.56 days to develop clinical signs of intoxication, significantly longer (p=0.0012) than Group 2 goats (7.83±3.81 days). Two Group 2 goats died on the same day that they developed clinical signs of intoxication. At necropsy of these two animals, no significant changes were observed. In the second experiment, samples of A. septentrionalis were sprayed with a solution containing H. seropedicae. Before and eight days after spraying, the samples were pressed and dried for quantitation of MFA. The amount of MFA present in samples of A. septentrionalis 8 days after spraying with H. seropedicae was significantly lower (p=0.017) than that found prior to spraying. It can be concluded that administration of H. seropedicae in goats is capable of causing greater resistance to A. septentrionalis intoxication, and spraying the plant with this bacterium significantly reduces the amount of MFA in the plant.

A new fluorophore containing 2,1,3-benzothiadiazole unit with alkylated tetrazole terminal groups as electron donors connected through a π-conjugated system of the type (D-π-A-π-D) was synthesized using the Sonogashira coupling reaction with good yields. The genotoxicity of the two intermediate compounds and the final product was evaluated in vitro in consideration of the potential application of the new compound in the chemical production of photovoltaic paints. The new fluorophore did not show significant biological effects in the cell viability test and the comet assay when compared with the intermediate compounds that were obtained synthetically despite the ability to interact with deoxyribonucleic acid (DNA) as demonstrated in circular dichroism assays. Thus, the compound does not show toxic or genotoxic activity, and therefore, it can be applied as a pigment in photovoltaic paint.

Abstract Paraburkholderia tropica (syn Burkholderia tropica) are nitrogen-fixing bacteria commonly found in sugarcane. The Paraburkholderia tropica strain Ppe8 is part of the sugarcane inoculant consortium that has a beneficial effect on yield. Here, we report a draft genome sequence of this strain elucidating the mechanisms involved in its interaction mainly with Poaceae. A genome size of approximately 8.75 Mb containing 7844 protein coding genes distributed in 526 subsystems was de novo assembled with ABySS and annotated by RAST. Genes related to the nitrogen fixation process, the secretion systems (I, II, III, IV, and VI), and related to a variety of metabolic traits, such as metabolism of carbohydrates, amino acids, vitamins, and proteins, were detected, suggesting a broad metabolic capacity and possible adaptation to plant association.

Abstract Lupinus albescens is a resistant cover plant that establishes symbiotic relationships with bacteria belonging to the Bradyrhizobium genus. This symbiosis helps the development of these plants in adverse environmental conditions, such as the ones found in arenized areas of Southern Brazil. This work studied three Bradyrhizobium sp. (AS23, NAS80 and NAS96) isolated from L. albescens plants that grow in extremely poor soils (arenized areas and adjacent grasslands). The genomes of these three strains were sequenced in the Ion Torrent platform using the IonXpress library preparation kit, and presented a total number of bases of 1,230,460,823 for AS23, 1,320,104,022 for NAS80, and 1,236,105,093 for NAS96. The genome comparison with closest strains Bradyrhizobium japonicum USDA6 and Bradyrhizobium diazoefficiens USDA110 showed important variable regions (with less than 80% of similarity). Genes encoding for factors for resistance/tolerance to heavy metal, flagellar motility, response to osmotic and oxidative stresses, heat shock proteins (present only in the three sequenced genomes) could be responsible for the ability of these microorganisms to survive in inhospitable environments. Knowledge about these genomes will provide a foundation for future development of an inoculant bioproduct that should optimize the recovery of degraded soils using cover crops.

ABSTRACT Objectives Advanced glycation end products (AGEs) are involved in the pathogenesis and complications of diabetes mellitus (DM). Gestational DM (GDM) is characterized by increased glycemia and oxidative stress, which are factors associated with high serum AGE concentrations. The aim of this study was to evaluate the utility of a serum fluorescence AGE (F-AGE) method as a screening tool for gestational diabetes. Subjects and methods Serum samples from 225 GDM patients and 217 healthy pregnant women (healthy controls) were diluted 50-fold in phosphate-buffered saline, and the AGEs were estimated by fluorometric analysis (λEx 350 nm/ λEm 440 nm). Results No significant (P > 0.05) differences in AGE concentrations, expressed in Arbitrary Units (UA/mL × 104), were observed in the women with GDM or in the healthy controls. Furthermore, F-AGE concentrations did not change significantly during the pregnancy (12-32 weeks of gestation). Only the GDM group had a positive correlation (r = 0.421; P < 0.001) between F-AGEs and serum creatinine concentrations. Conclusion It was not possible to distinguish women with gestational diabetes from the healthy controls on the basis of serum F-AGE concentrations.

Objective To investigate the association of the rs10885122G>T polymorphism in the ADRA2A gene in a Euro-Brazilian sample of healthy (controls) and type 2 diabetic (T2D) subjects. Subjects and methods We used fluorescent probes (TaqMan) to genotype 241 subjects, that is, 121 healthy and 120 T2D subjects, who were classified based on the Brazilian Diabetes Association (2013) and American Diabetes Association (2014) criteria. Results The genotype and allele frequencies showed no significant (P > 0.05) difference between the two studied groups. The minor allele (T) frequencies (95%CI) for rs10885122 were 19% (14-24%) and 20% (15-26%) for healthy and T2D groups, respectively. Carriers of the T allele (genotypes GT+TT) were significantly associated (P = 0.016) with approximately a 7-kg body weight reduction compared with the genotype GG, which was only found in the T2D group. Conclusion The rs10885122G>T polymorphism of the ADRA2A gene was not associated with T2D in Euro-Brazilians, and carriers of the T allele had lower body weight in the presence of T2D. Arch Endocrinol Metab. 2015;59(1):29-33

A hiperglicemia crônica, presente em todas as formas de diabetes, favorece a formação de produtos finais de glicação avançada (AGEs). A interação de AGEs com o receptor de produtos finais glicosilados (RAGE) inicia uma cascata de processos pró-inflamatórios e pró-coagulantes que resultam em estresse oxidativo, o qual estimula a formação e o acúmulo de maior quantidade de moléculas de AGEs. Esse processo cíclico, denominado memória metabólica, pode explicar por que, mesmo após um período de bom controle glicêmico, as complicações vasculares associadas ao diabetes não regridem. O RAGE fixado nas membranas de várias células também está presente em isoformas solúveis (esRAGE e cRAGE), geradas por processamento alternativo do ácido desoxirribonucleico (DNA) ou por clivagem proteolítica. Esta revisão aborda os novos estudos sobre a função desses mediadores como potenciais biomarcadores para as complicações vasculares no diabetes.

Chronic hyperglycemia, which is present in all types of diabetes, increases the formation of advanced glycation end-products (AGEs). The interaction of AGEs with receptor of advanced glycation end-products (RAGE) initiates a cascade of pro-inflammatory and pro-coagulant processes that result in oxidative stress, stimulating the formation and accumulation of more AGE molecules. This cyclic process, denominated metabolic memory, may explain the persistency of diabetic vascular complications in patients with satisfactory glycemic control. The RAGE found in several cell membranes is also present in soluble isoforms (esRAGE and cRAGE), which are generated by alternative deoxyribonucleic acid splicing or by proteolytic cleavage. This review focuses on new research into these mediators as potential biomarkers for vascular complications in diabetes.

Este trabalho teve por objetivo comparar a eficiência na seleção de genótipos e a qualidade das estimativas dos componentes de variância e da herdabilidade, empregando o delineamento em blocos aumentados (DBA), o delineamento em blocos aumentados duplicados (DBAD) e o grupo de experimentos em blocos casualizados com tratamentos comuns (EBCTC). Para a comparação, foi imposta a condição de que o número de genótipos sob seleção era maior do que o número de unidades experimentais disponíveis para os delineamentos com repetição. Quatro cenários foram compostos da combinação de diferentes valores de herdabilidade e do coeficiente de variação residual paramétricos. Das 2.400 simulações por cenário, o DBA apresentou a maior eficiência de seleção. Os delineamentos com repetição (DBAD e EBCTC) apresentaram eficiência de seleção semelhante entre si. É possível concluir que a não realização de repetições, avaliando-se um maior número de genótipos, pode trazer melhores resultados ao programa de melhoramento de plantas.

This study aimed to compare the efficiency in the selection of genotypes and the quality of the estimates of the variance components and heritability using the augmented block designs (ABD), the duplicated augmented block designs (DABD) and the group of randomized blocks design experiments with common treatments (ERBCT). For comparison, it was imposed a condition that the number of genotypes under selection was greater than the number of units available for experimental designs with repetition. Four scenarios were composed of a combination of different values of heritability and parametric residual coefficient of variation. From the 2400 simulations per scenario the ABD had the highest selection efficiency. The designs with repetition (DABD and ERBCT) had similar selection efficiency between them. It is possible to conclude that not using repetitions, and therefore, evaluating a larger number of genotypes, can bring better results to the plant breeding program.