Abstract: The aim of this study was to evaluate the isolated effect and the combination of products in the chemical treatment on the physiological potential of soybean seeds with different vigor levels, after different storage periods. The study was divided into four experiments, with different storage periods: 0, 45, 90 and 135 days, all with a completely randomized design, with four replicates. The treatments were arranged in a 12 x 2 (A x B) factorial scheme, in which factor A consisted of the application of seed treatment and factor B consisted of initial vigor levels. The physiological potential of the seeds was determined by means of the following evaluations: first germination count, seed germination, seedling emergence in the sand substrate, accelerated aging with NaCl-saturated solution, vigor index and average seedling length (Vigor-S®). Storage of seeds under uncontrolled conditions causes greater deterioration, and this process can be intensified by previous chemical treatment of the seeds. Among the products studied, the use of drying powder alone was the treatment that caused the greatest losses in the different situations studied. To ensure the maintenance of the physiological potential of soybean seeds, treatment should be carried out as close as possible to sowing.

Resumo: O objetivo deste estudo foi avaliar o efeito isolado e a combinação de produtos no tratamento químico, sobre o potencial fisiológico de sementes de soja com diferentes níveis de vigor, em períodos de armazenamento distintos. O estudo foi dividido em quatro experimentos, com diferentes tempos de armazenamento: 0, 45, 90 e 135 dias todos com delineamento inteiramente casualizado, com quatro repetições. Os tratamentos foram dispostos em esquema fatorial 12 x 2 (A x B), em que o fator A foi composto pela aplicação do tratamento de sementes e o fator B pelos níveis de vigor inicial. O potencial fisiológico das sementes foi determinado por meio: primeira contagem de germinação, germinação, emergência de plântulas em areia, envelhecimento acelerado com solução saturada com NaCl, índice de vigor e comprimento médio de plântulas (Vigor-S®). O armazenamento de sementes em condições não controladas ocasiona maior deterioração das sementes e este processo pode ser intensificado pelo prévio tratamento químico das sementes. Dentre os produtos estudados, o uso de pó-secante de maneira isolada foi o tratamento que ocasionou maiores perdas nas diferentes situações estudadas. Para garantir a manutenção do potencial fisiológico das sementes de soja, recomenda-se que o tratamento seja realizado o mais próximo possível da semeadura.

ABSTRACT The objective of this study was to conduct a meta-analysis and test its efficiency in summarizing the heterogeneous data of heritability estimates for the traits of grain yield (GY) and popping expansion (PE), and to provide reliable estimates of selection gains in popcorn. Therefore, 97 heritability estimates (ĥ 2) for popcorn GY and PE in the broad and narrow sense were used. The main procedures underlying the estimation of the combined heritability (ĥ 2 + ) using the technique of meta-analysis consisted of i) an exploratory analysis of the set of heritability estimates to detect outliers using a box-plot chart, ii) the verification of the required statistical assumptions, iii) testing the involved heritability estimates for homogeneity, and iv) the calculation of the estimates of combined heritability. The meta-analysis facilitated the synthesis of the information pertaining to heritability in popcorn. The combined heritability estimates (ĥ 2 + ) in the broad sense for GY and PE were 0.5208 ± 0.0229 and 0.6356 ± 0.0209, respectively, and in the narrow sense were 0.3290 ± 0.0292 and 0.3083 ± 0.0298, respectively.

Resumo: O objetivo deste estudo foi avaliar a eficiência do teste de envelhecimento acelerado para determinar o potencial fisiológico de sementes de soja com diferentes tratamentos químicos; verificar a influência do tratamento de sementes após o armazenamento e analisar a concordância entre os métodos de envelhecimento acelerado com os resultados reais de armazenamento das sementes. O estudo foi dividido em dois experimentos, ambos com delineamento inteiramente casualizado, com quatro repetições. No primeiro experimento os tratamentos foram dispostos em esquema fatorial 3 x 2 x 3: três tratamento de sementes (imidacloprid + thiodicarb; fipronil + thiophanate methyl + pyraclostrobin; ausência de tratamento), dois níveis de vigor (alto; baixo) e três métodos de envelhecimento acelerado (tradicional; solução saturada de NaCl; sem envelhecimento) avaliando-se a germinação. No segundo experimento, os tratamentos foram dispostos em esquema fatorial 3 x 2 x 2: três tratamentos de sementes (imidacloprid + thiodicarb; fipronil + thiophanate methyl + pyraclostrobin; ausência de tratamento), dois níveis de vigor (alto; baixo), dois tempos de armazenamento (0 e 135 dias), avaliando-se a germinação e emergência de plântulas. Os métodos de envelhecimento acelerado foram eficientes para determinar o potencial fisiológico das sementes, em que, o NaCl apresentou melhores resultados. O potencial fisiológico das sementes de soja reduziu ao longo do armazenamento e a aplicação de produtos químicos no tratamento de sementes prejudicou as porcentagens de germinação e emergência, independente do ingrediente ativo utilizado. O método de envelhecimento acelerado com NaCl apresenta maior concordância com os resultados reais de armazenamento.

Abstract: This work evaluated the efficiency of accelerated aging test to determine the physiological potential in treated soybean seeds with fungicides and insecticides, in addition to analyzing the concordance between the results obtained by different accelerated aging methods with the actual results of the physiological quality in seeds after the storage. The study was divided into two experiments, both with entirely randomized delineation, with four replications. In the first experiment, seed germination was evaluated after imposing some treatments that were arranged in a 3 x 2 x 3 factorial scheme: seed treatment (imidacloprid + thiodicarb; fipronil + thiophanate methyl + pyraclostrobin; no treatment); vigor levels (high; low); and accelerated aging (traditional; saturated NaCl solution; no aging). In the second experiment, seedling emergence was evaluated after applying some treatments that were arranged in a 3 x 2 x 2 factorial scheme: seed treatment (imidacloprid + thiodicarb; fipronil + thiophanate methyl + pyraclostrobin; no treatment); vigor levels (high; low); storage time (0 and 135 days). The accelerated aging methods were efficient to determine the physiological potential of the seeds, in which, the NaCl method presented better results. The physiological potential of soybean seeds decreased throughout storage and the application of chemicals in seed treatment impaired the germination and emergence percentages, regardless of the active ingredient used. The accelerated aging method with NaCl presents greater agreement with the actual storage results.

ABSTRACT. The success of sugarcane (Saccharum spp.) breeding programs depends on the choice of productive parent lines that have a high industrial yield and are genetically divergent. This study assessed the genetic divergence and population structure of sugarcane accessions that are the parents of the RB05 Series of the Sugarcane Breeding Program of Brazil. The DNA of 82 accessions was evaluated using 36 simple sequence repeat markers. The Jaccard similarity coefficient and Unweighted Pair Group Method with Arithmetic Mean clustering method were used to generate a cluster that was divided into 17 distinct groups derived from probabilistic models. The similarity coefficient used in both cases showed that the degree of similarity varied from 0.4716 (RB971551 x RB965586) to 0.9526 (RB936001 x SP89-1115), with a mean of 0.8536. This result demonstrates a high similarity between the 82 accessions and confirms Wright’s F statistic (0.125), which indicates moderate genetic variability. The less-similar crosses suggest that breeders seek a higher number of crosses using cultivar RB965586, highlighting the RB971551 x RB965586 and RB965586 x RB855511 crosses. The results demonstrate that crosses such as RB936001 x SP89-1115 and RB945954 x RB896342 should be avoided because of their high genetic similarity.

ABSTRACT. Statistics is the main science by which researchers validate the results of scientific work, and the choice of an inadequate statistical method may lead to conclusions that are considered questionable by reviewers. This study had the objective of describing the characteristics of the statistical methods used in the papers published in Acta Scientiarum. Agronomy from 1998 to 2016 as part of a a critical analysis of the journal to pinpoint possible failures in the application of these methods. All scientific articles (n = 1,237) published in the journal were surveyed, of which 54.1% addressed areas of crop production. The mean comparison methods were the most commonly used (75.5%) and, consequently, they represented the highest proportion of errors (60.8%) of the authors in the journal.