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As new cultivation techniques arise, crops require the development of new technologies and management practices that aim higher yields with lower production cost. Thus, the objective of this study was to evaluate the efficiency of co-inoculation and different ways of application of Bradyrhizobium japonicum and Azospirillum brasilense and nitrogen fertilization on nodulation and yield of soybean. The experiment was established in November 2013 in an area located in the Iguatemi Experimental Farm, of State University of Maringa (UEM). The design was a randomized block with four replications. The treatments consisted of a control, fertilization with nitrogen (200 kg N ha -1 ), standard inoculation in seeds (liquid and peat inoculant), co-inoculation on seed and co-inoculation at sowing, using different doses of inoculant B. japonicum and A. brasilense. The following determinations were carried out in the field and in the laboratory: number of nodes at flowering, mass of nodules at flowering, the shoot dry mass, nitrogen content in the shoot, grain nitrogen content, number of pods/plant, thousand grain mass and yield. The results showed that inoculation through seed treatment with liquid inoculant presents an adequate option to farmers, in the conditions of this experiment. Nitrogen fertilization did not increase yield and yield components, being unnecessary. more...

Industrial seed treatment assures uniform coverage of seeds with insecticides, fungicides, micronutrients and bioestimulant at precise dose, however often resulting in higher slurry volume. Furthermore, seeds are coated long periods of time prior sowing and may influence germination and vigor. Thus, the aim of this work was to evaluate the influence of seven industrial seed treatments and their respective slurry volumes on the physiological potential of soybean seeds at 0, 15, 30, 45, 60 and 90 days of storage. In each storage period, the variables germination, accelerated aging test and emergency speed index were evaluated and studied in the repeated measures in time model. The products used were: fungicide (thiabendazole, fludioxonil and mefenoxam), insecticide (thiametoxam), insecticide/nematicide (abamectin), micronutrients (cobalt and molybdenum), bioregulator, drying powder and polymer. High volumes of seed-coating mixtures reduce the physiological quality of soybean seeds over storage. However, the slurry composition also influenced on the maintenance of the seed germination and vigor throughout the storage. more...

The aim of the study was to evaluate seed germination and vigor of maize subjected to different products and storage periods. The experimental design was completely randomized in a split plot on time. In the plots were distributed nine treatments: an untreated control, one treatment called “standard treatment”, with addition of fungicide (fludioxonil + metalaxyl-M) and insecticide (thiamethoxam). From the standard treatment, six treatments with combinations of inoculant (Azospirillum brasilense), micronutrients (nitrogen + potassium + zinc + boron + copper + iron + manganese + molibdenium) and bioregulator. Lastly, a treatment called “complete treatment” including all products. In subplots the storage periods of zero, 15, 30, 45, 60 and 90 days were evaluated. Seed vigour of maize was reduced by seed treatments and storage. Micronutrients addition resulted in higher fitotoxicity in comparison to the addition of other products, regardless of storage period. The treatment with the combination of fungicide, insecticide and inoculant proved to be feasible, and was the most promising seed treatments. None of the studied treatments affected the germination in up to 45 days of storage, however the complete treatment with 3200 mL .100 kg-1 reduced seed vigour. Resumo: O objetivo do trabalho foi avaliar a germinação e vigor das sementes de milho submetidas a diferentes produtos e períodos de armazenamento. O delineamento experimental foi inteiramente casualizado em esquema de parcelas subdivididas no tempo. Na parcela foram distribuídos nove tratamentos: uma testemunha não tratada, um tratamento denominado de “tratamento padrão”, com adição de fungicida (fludioxonil + metalaxyl-M) e inseticida (thiamethoxam). A partir do tratamento padrão, seis tratamentos com combinações de inoculante (Azospirillum brasilense), micronutrientes (nitrogen + potassium + zinc + boron + copper + iron + manganese + molibdenium) e biorregulador. Por fim, um tratamento denominado de “tratamento completo”, incluindo todos os produtos. Na subparcela, os períodos de armazenamento 0, 15, 30, 45, 60 e 90 dias foram avaliados. O vigor das sementes de milho foi reduzido pelos tratamentos de sementes e pelo armazenamento. A adição de micronutrientes resultou em maior fitotoxicidade em comparação à adição de outros produtos, independente do período de armazenamento. O uso de fungicida, inseticida e inoculante se mostram viáveis, como os mais promissores tratamentos de sementes. Nenhum dos tratamentos estudados afetaram a germinação até 45 dias de armazenamento, porém o tratamento completo, com 3200 mL. 100 kg-1 reduziu o vigor de sementes. more...