Resumen Phoenix roebelenii es una especie de palma muy utilizada en Brasil debido a sus hojas exuberantes y su adaptabilidad a diferentes tipos de clima. Por esto, resulta importante obtener información detallada sobre la viabilidad, vigor y longevidad de sus semillas deshi dratadas y almacenadas. La presente investigación comprendió dos etapas. La primera tuvo como objetivo evaluar la respuesta de las semillas a la desecación y almacenamiento con base en protocolos formales. En la segunda, las semillas se desecaron hasta alcanzar el 33, 30, 25, 23, 20, 18, 16, 12, 10 y 7% de contenido de agua. Luego de alcanzar cada nivel de agua establecido para cada tratamiento, las semillas fueron sometidas a pruebas de germi nación. A los 65 días después de la siembra se midió: longitud del sistema radicular y del brote, el área, volumen y diámetro del sistema radicular, la longitud del eófilo y el peso fresco y seco de las plántulas. Por um lado, se observó un aumento significativo en el porcentaje de germinación y en la longitud del eófilo en función del menor contenido de agua de la semilla. Por otro lado, el diámetro del collar disminuyó como consecuencia de la desecación de la semilla.

Abstract Phoenix roebelenii is a palm species widely used in Brazil due to its exuberant leaves and adaptability to different climatic variations. For proper propagation, detailed information about seed viability, vigor and longevity subjected to dehydration and storage is yet to be obtained. For this purpose, the present research comprised two stages. The first one aimed at evaluating the response of seeds to desiccation and storage based on formal protocols. In the second stage, seeds were desiccated to 33, 30, 25, 23, 20, 18, 16, 12, 10 and 7% of water content by monitoring water loss in a convection oven at 35±2°C. After reaching each established water content, the seeds were subjected to germination tests. At 65 days after sowing, root length, root area, volume and diameter, shoot and eophyll length, and total seedling fresh and dry weights, were measured. Significant increases in germination and eophyll length were observed for lower seed water contents. Aversely, collar diameter decreased with seed desiccation.

ABSTRACT. Sorghum (Sorghum bicolor) is highly sensitive to zinc deficiency in soils, which results in decreased productivity and low-quality agricultural products. Our objective was to evaluate the effects of different zinc doses, applied to seeds, on the physiological quality and initial performance of sorghum plants. Six doses (0, 3.5, 7.0, 14.0, 21.0, and 28.0 g kg-1 seeds) were used and an uncoated control. The Zn coating process used dolomitic limestone as the filler and glue. Laboratory tests were conducted in a completely randomized design and greenhouse experiments were conducted in a randomized block design. The control means were 8, 9, and 14% lower than the maximum, minimum, and total seed area of treatments, respectively, relative to that of treatments. The control differed from other treatments by 10.47 in the speed index of emergence. Zinc at a dose of 28 g kg-1 seeds provided greater production of aerial dry matter, with nutrient content of 75.85 mg kg-1. Zinc on sorghum seeds affected length and dry matter production of aerial parts and roots but did not affect physical characteristics, germination, or emergence time. Applied zinc accumulated mainly in the roots, and promotes changes in Ca and Mg in seeds and other plant parts.

RESUMO: No processo de revestimento, os materiais cimentantes são os responsáveis por conferir a adesão dos materiais de enchimento às sementes. Concentrações adequadas de material cimentante promovem revestimento com boas características físicas e que não prejudiquem as características fisiológicas das sementes. Assim, o objetivo desse trabalho foi verificar o tipo e a concentração de material cimentante que possibilite as melhores características físicas e fisiológicas em sementes revestidas de estilosantes Campo Grande. O revestimento foi realizado em drageadora, utilizando areia como material de enchimento. Os tratamentos foram compostos por 2 tipos de materiais cimentantes em 3 proporções (cola cascorez extra e cola goma arábica, diluídas em água, 3:1, 2:1 e 1:1), além das sementes não revestidas, como controle. Após o revestimento, as sementes foram avaliadas quanto às características físicas e fisiológicas. O delineamento adotado foi inteiramente casualizado em laboratório e em casa de vegetação. Verificou-se que as colas cascorez extra e goma arábica não interferiram na qualidade fisiológica das sementes de estilosantes Campo Grande nas diferentes concentrações utilizadas. Entretanto, a cola cascorez extra na proporção 2:1 proporcionou maior área, diâmetro máximo, diâmetro mínimo e esfericidade nas sementes revestidas.

ABSTRACT: The binder materials used in seed coating provide adherence of the filler materials onto the seeds. Adequate concentrations of the binder promote good physical characteristics of coating while not impairing seed physiological characteristics. Thus, the objective of this study was to evaluate the type and the concentration of binder materials that allow the best physical and physiological characteristics in coated seeds of Campo Grande Stylosanthes. Seed coating was carried out in a coating pan, using sand as the filling material. The treatments consisted of 2 types of binders mixed in 3 ratios (PVA glue and gum arabic glue, diluted in water, 3:1, 2:1, and 1:1), and uncoated seeds as control. The coated seeds were evaluated for physical and physiological characteristics. The laboratory and greenhouse experiments were arranged in a completely randomized design. Results showed that at the different concentrations used this study, neither the PVA glue nor the gum arabic glue had any effect on the physiological quality of Campo Grande Stylosanthes seeds. However, PVA glue in the ratio of 2:1 provided the greatest surface area, maximum diameter, minimum diameter, and sphericity to coated seeds.

Resumo: A soja perene (Neonotonia wightii) é uma Fabaceae com potencial para ser utilizada em consórcio com plantas da família Poaceae, a fim de melhorar a qualidade das pastagens. Na busca por agregar valor às sementes de soja perene e melhorar a sua distribuição na semeadura, sementes revestidas com diferentes materiais foram caracterizadas via análise de imagem digital e os atributos físicos relacionados com atributos fisiológicos, a fim de definir a quantidade e o material ideais a serem utilizados no revestimento. Foram testados 150 g, 200 g e 250 g de material divididos em camadas, sendo eles: areia, silicato de cálcio + areia e calcário + areia. O recobrimento promoveu incrementos máximos de aproximadamente 350% à massa das sementes e aumentos significativos de até 230% na área, 154% no diâmetro máximo, 162% no diâmetro mínimo, 167% no diâmetro contido e 152% no perímetro. O recobrimento foi eficiente, também, em reduzir a umidade dos péletes com o aumento das camadas que recobrem as sementes. A combinação de areia + calcário resultou nos maiores péletes. A combinação de areia + silicato não interferiu na velocidade e formação de plantas, sendo considerado o material adequado para o recobrimento de sementes de soja perene.

Abstract: Perennial soybean (Neonotonia wightii) is a Fabaceae with potential to be used in consortium with Poaceae plants to improve pasture quality. In order to add value to perennial soybean seeds and improve their seed distribution, seeds coated with different materials in coating machine were characterized by digital image analysis and physical attributes related to physiological attributes in order to define the ideal amount and material to be used in the coating. Different material quantities were tested, 150 g, 200 g and 250 g, divided into layers, namely: sand, calcium silicate + sand and limestone + sand. Coating promoted maximum increments of approximately 350% in seed mass and significant increases of up to 230% in area, 154% in maximum diameter, 162% in minimum diameter, 167% in contained diameter and 152% in perimeter. The coating was also efficient in reducing the moisture of the pellets by increasing the layers that cover the seeds. The sand + limestone combination resulted in the largest pellets. The combination of sand + silicate did not interfere with plant speed and formation. Thus, it was considered the appropriate material for the coating of perennial soybean seeds.