-The aim of this study was to evaluate the physiological quality of soybean seeds submitted or not to dynamic cooling, and kept in cold storage (CS) and non-cold storage (NCS). A soybean seeds lot, variety M7639RR, was divided into two parts, and each one was subdivided into three parts that were subjected to one of these cooling procedure: seeds without cooling (SWC), dynamic cooling at 17 °C (SC17), and dynamic cooling at 13 °C (SC13). Seeds were kept in CS and NCS at 20 °C. Samples were collected at six times (0, 45, 90, 135, 180 and 225 days), and then submitted to germination, tetrazolium, accelerated aging and seedling emergence tests. Dynamic artificial cooling at 13 °C followed by maintenance at 20 °C ensured the preservation of physiological quality of soybean seeds for up to 225 days. The vigor of the soybean seeds subjected to dynamic cooling at 13 °C was better preserved than that of the non-cooled or of the cooled at 17 °C ones and kept in NCS for 225 days. CS at 20 °C contributed to the preservation of the physiological quality of the soybean seeds, regardless of whether or not they were submitted to the dynamic procedure.Index terms: Glycine max, artificial cooling, germination, vigor Resfriamento de sementes de soja e qualidade fisiológica no armazenamento RESUMO -O objetivo do trabalho foi avaliar a qualidade fisiológica de sementes de soja submetidas ou não ao resfriamento dinâmico e mantidas em armazém resfriado (AR) e não resfriado (ANR). Um lote de sementes de soja, variedade M7639RR, foi dividido em duas partes, que foram subdivididas em três partes, cada uma submetida a um procedimento de resfriamento: sementes não resfriadas (SNRE), resfriamento dinâmico a 17 °C (SRE17) e a 13 °C (SRE13). As sementes foram mantidas em um ANR e em AR a 20 °C. Foram coletadas amostras em seis momentos (0, 45, 90, 135, 180 e 225 dias), e as sementes foram submetidas aos testes de germinação, tetrazólio, envelhecimento acelerado e emergência de plântulas em canteiro. O resfriamento dinâmico artificial a 13 ºC seguido de manutenção em AR a 20 ºC assegurou a preservação da qualidade fisiológica de sementes de soja por até 225 dias. Sementes de soja submetidas ao resfriamento dinâmico a 13 °C preservam melhor o vigor, comparativamente às não resfriadas ou resfriadas a 17 °C e mantidas em ANR por 225 dias. O AR a 20 °C contribui para preservação da qualidade fisiológica da semente de soja, independentemente de a semente ser ou não submetida ao procedimento dinâmico.Termos para indexação: Glycine max, resfriamento artificial, germinação, vigor.

A proteção das sementes contra pragas e doenças nas fases iniciais do desenvolvimento da cultura é de grande importância para a cadeia produtiva da soja. A aplicação de inseticidas e fungicidas via revestimento de sementes proporciona esta proteção, no entanto, não deve ocasionar prejuízos à qualidade fisiológica dos lotes de sementes, seja imediatamente depois do revestimento ou após armazenamento. Para avaliar o efeito do revestimento de sementes de soja com vários agroquímicos sobre a qualidade fisiológica das mesmas durante o armazenamento, foram realizados dois ensaios com as cultivares M6972 IPRO e M7739 IPRO. Vinte quilogramas de cada cultivar foram submetidos a revestimento com os produtos Cropstar, Derosal Plus, Standak Top e Avicta Completo, avaliando -se a primeira contagem de germinação, germinação, envelhecimento acelerado e emergência em canteiro das sementes, durante 60 dias de armazenamento sob condições ambientais não controladas. O armazenamento sob condições de temperatura e umidade relativa não controladas influencia negativamente a qualidade fisiológica das sementes de soja. As cultivares usadas responderam de forma diferente ao revestimento de sementes com os diferentes agroquímicos testados. O revestimento de sementes de soja da cultivar M6972 IPRO com Standak Top ou com Avicta Completo mantem a percentagem de emergência de plântulas durante os 60 dias de armazenamento. O revestimento de sementes de soja da cultivar M7739 IPRO com Standak Top ocasiona maior qualidade fisiológica de sementes do que os demais revestimentos. Palavras -chave: fitofármacos, fungicida, Glycine max, inseticida, tratamento de sementes. A B S T R A C TThe protection of seeds against pests and diseases in the early stages of crop development is of great importance to the soybean production chain. Coating seeds with insecticides and fungicides provides this protection; however, it should not cause damage to the physiological quality of seed lots, immediately after coating or after storage. To evaluate the effect of soybean seed coating with various agrochemicals on the physiological quality of seeds during storage, two assays were conducted with the cultivars M6972 IPRO and M7739 IPRO. Twenty kilograms of each cultivar were subjected to coating with products Cropstar, Derosal Plus, Standak Top and Avicta Completo, evaluating the first counting of germination, germination, accelerated aging and seedling emergence of seeds for 60 days of storage under environmental conditions. Storage under not controlled conditions of temperature and relative humidity negatively influences the physiological quality of soybean seeds. The cultivars used responded differently to the seed coating with different agrochemical tested. Soybean seed coating of cultivar M6972 IPRO with Standak Top or Avicta Completo maintains the percentage of seedling emergence during the 60 days of storage. Soybean seed coating of cultivar M7739 IPRO with Standak Top brings better physiological seed quality than other coatings.

Currently, the standard germination test (SGT) is the official test for evaluating seed viability in seed testing laboratories around the world. The SGT takes 3 to 4 wk to complete for most grasses, including the dormancy breaking treatment period. The tetrazolium test (TZT), however, offers quick viability determination within 24 to 48 h, even for dormant seeds. This study was conducted to compare SGT and TZT results for tall fescue (TF), annual and perennial ryegrass (ARG and PRG), orchardgrass (OG), bentgrass (BG), Kentucky bluegrass (KBG), and fine fescues (FF). A total of 3432 samples representing the seven species were evaluated for viability by SGT and TZT during 2009 to 2013 at the Oregon State University Seed Laboratory (OSUSL). According to the germination tolerance table of the Association of Official Seed Analysts (AOSA), both SGT and TZT results were within tolerance in 94.2% of TF samples, 95.2% of ARG samples, 90.4% of PRG samples, 93.7% of OG samples, 90.8% of FF samples, 83.9% of BG samples, and 42.4% of KBG samples. Dormancy was the main reason for higher viability by TZT results than by SGT in the same sample, causing the two test results to be out‐of‐tolerance. Based on these results, it can be concluded that the TZT can be used as an alternative viability test to the SGT for TF, ARG, PRG, OG, FF, and possibly for BG. However, the KBG has higher levels of dormancy, which brings the SGT below the TZT results, especially for freshly harvested seeds.

-Isolates of Pseudomonas veronii (DFs513), Bacillus spp. (DFs093 and DFs348), Bacillus cereus (DFs769), Rodhococcus fascians (DFs843 and DFs912) and Pseudomonas fluorescens (DFs831 and DFs842), selected for Xanthomonas axonopodis pv. phaseoli control, and a combination of some of these bacteria isolates, were evaluated for possible influence on Colletotrichum lindemuthianum transmission from naturally infected and/or infested bean seeds to seedlings. In the first trial, using the paper roll method, seeds were sown in eight replications of 25 seeds that were incubated at 20 ± 2°C. Germination percentage and pathogen incidence were evaluated. In the second trial, pathogen transmission to seedlings was evaluated in sterile substratum and incubated for 10 days. Daily emerged seedlings, pathogen incidence, leaf and root dry mass were

-Reducing the execution time of the tetrazolium test is important because it is used for making decisions during the preharvest and this test takes approximately 24 h. Thus, the goal of this research was to study preconditioning and staining periods and concentration of tetrazolium salt, in order to reduce the evaluation time of rice seed viability by tetrazolium test. Three independent experiments were conducted. In the first and second experiments, six rice seed lots from the BR Irga 424 cultivar were used. In the first experiment, different concentrations of tetrazolium salt (0.1, 0.25, 0.5 and 1 %) and staining times (0.5, 1.0 and 2.0 h) were evaluated. In the second one, different hydration periods (0.5, 1.0, 2.0 and 4.0 h) at two temperatures (35 and 40 °C) were tested. In the third one, eight seed lots from the same cultivar were used, and the effectiveness of the modified tetrazolium test in the evaluation of rice seed viability was assesed. It is possible to carried out the tetrazolium test on rice using the hydration of peeled seeds for 1 h at 40 °C and staining for 1 h with a 0.25% salt concentration.Index terms: physiological quality, seed viability, Oryza sativa L.Ajustes metodológicos para o teste de tetrazólio em sementes de arroz RESUMO -A redução no tempo de execução do teste de tetrazólio é importante, pois esse teste muito utilizado para tomada de decisão em pré-colheita, consome aproximadamente 24 h. Dessa forma, objetivou-se nesta pesquisa estudar períodos de pré-condicionamento e de coloração e concentração do sal de tetrazólio visando reduzir o tempo de avaliação da viabilidade de sementes de arroz pelo teste de tetrazólio. Foram conduzidos três experimentos independentes, nos experimentos I e II foram utilizados seis lotes de sementes de arroz da cultivar BR Irga 424. No experimento I foram avaliadas diferentes concentrações do sal de tetrazólio (0,1; 0,25; 0,5 e 1%) e períodos de coloração (0,5; 1,0; e 2,0 h). No experimento II foram testados diferentes períodos de hidratação (0,5; 1,0; 2,0 e 4,0 h) em duas temperaturas (35 e 40 °C). No experimento III foram utilizados oito lotes de sementes da mesma cultivar e foi avaliada a eficiência do teste de tetrazólio modificado na avaliação da viabilidade de sementes de arroz. É possível realizar o teste de tetrazólio em arroz utilizando hidratação de sementes descascadas por 1 h a 40 °C e coloração por 1 h com concentração do sal a 0,25%.Termos para indexação: qualidade fisiológica, viabilidade, Oryza sativa L.