Physical and physiological properties of seed corn separated by a gravity table

This study was conducted to evaluate the effectiveness of a gravity table for separating seed corn into fractions of different quality, and to correlate the physical and physiological properties of each fraction of seed corn;Five lots of seed corn with five sizes (unsized, large flat, large round, small flat, and small round) were conditioned through two types of gravity table (pressure and suction type). The original sample, obtained before the gravity table separation, and four fractions (heavy, medium heavy, medium light, and light) obtained from the discharge edge of each gravity table, were analyzed for physical (bulk density, weight of 100 seeds, volume, specific gravity, terminal velocity, purity, breakage susceptibility, and pericarp injury), physiological (standard germination, cold germination, conductivity, and field emergence), and chemical composition (NIR protein, oil, and starch contents);Both gravity tables performed similarly as determined by the seed quality of various fractions. Flat seed corn was better in seed quality than round seed corn. The gravity table was efficient in separating seed corn into fractions of different quality along the discharge edge of the gravity table deck. However, when the initial seed quality of a lot is high, only marginal improvement in seed quality was obtained. The light seed obtained from the low side of the gravity table did not meet the seed requirement and must be discarded. The medium light fraction may be re-conditioned to recover fractions of acceptable seed quality. Bulk density was the best physical property of the seed corn correlated with the physiological quality of the seed. Weight of 100 seed may be also used, but bulk density is preferable due to its higher relationship with field emergence than seed weight

Conveyors for Bulk Handling of Seed Soybeans

Six soybean-seed conveyors were evaluated for capacity and seed damage. The belt conveyor, the flight conveyor, and the nylon-brush auger did not cause significant damage to soybean seed during conveying. The capacity of the belt conveyor declined significantly at 30° angle of inclination. The steel-flighting auger caused the most amount of damage, followed by the auger with rubber intake, and the pneumatic conveyor

Potencial fisiológico de sementes de milho híbrido tratadas com inseticidas e armazenadas em duas condições de ambiente

Seed treatment is a widely disseminated practice in Brazilian cultural areas, which linked to other cultural practices, has contributed to the increase in productivity, cost reduction, final product improvement, environmental damage reduction as well as good seed protection in the field level and storage. The work had the objective to check the insecticide effect on the germination and vigor of the hybrid maize seeds, stored in two environmental conditions. The seeds were treated with three insecticides, identified as: Insecticide one (Thiametoxan); Insecticide two (Neonicotinoide) and Insecticide three [Neonicotinoide + (Imidaclopride+thiodicarbe)]. After being treated, the seeds were stored for a period of 270 days, in two different places, one with (10ºC) temperature and relative humidity (60%) and another under normal condition of storage. During this period evaluations were accomplished every 45 days, through germination and vigor tests. In addition to germination and cooling tests, sanitation analysis, seedling emergency and seed inoculation were carried out. After that the seeds were stored for a period of 30 days in environmental places with and without control of air condition. The results obtained allow to conclude that the maintenance of seed quality of hybrid maize, treated with insecticides, depends on the hybrid and chemical product used in their treatment and that the reduction in feasibility and vigor of seeds treated with thiametoxan is intensified due to the storage period extension.O tratamento de sementes é uma prática largamente difundida nas áreas agrícolas brasileiras, a qual, associada às demais práticas culturais, tem contribuído para o incremento na produtividade, redução de custos, melhoria da qualidade do produto final, redução de danos ao ambiente e oferta uma boa proteção às sementes, tanto em nível de campo quanto no armazenamento. O trabalho teve como objetivo verificar o efeito do tratamento inseticida sobre a germinação e o vigor das sementes de milho híbrido, armazenadas em duas condições de ambiente. As sementes foram tratadas com três inseticidas, identificados como: Inseticida 1 (Thiametoxan); Inseticida 2 (Neonicotinóide) e Inseticida 3 [Neonicotinóide+(Imidaclopride+Thiodicarbe)]. Após tratadas as sementes foram armazenadas por um período de 270 dias, em dois ambientes, sendo um com controle de temperatura (10ºC) e umidade relativa (60%) e outro em condições normais de armazenamento. Durante este período realizou-se avaliações a cada 45 dias, através dos testes de germinação e vigor. Além dos testes de germinação e teste de frio foi realizada a emergência de plântulas após as sementes permanecerem armazenadas por um período de 30 dias em ambientes sem controle e com controle das condições do ar. Os resultados obtidos permitem concluir que a qualidade das sementes armazenadas de milho híbrido, tratadas com inseticidas é influenciada pelo produto químico empregado no tratamento das mesmas, dependente do híbrido e das condições do ambiente de armazenamento e que a redução na viabilidade e no vigor de sementes tratadas com thiametoxan, intensifica-se com o prolongamento do período de armazenamento

Efectos del recubrimiento con sulfato de zinc sobre tasas de germinación y niveles de isoenzimas en semillas de algodón

Se han estudiado los parámetros fisiológicos y enzimáticos de semillas y plántulas de algodón variedad BRS 286 tratadas con sulfato de zinc, antes y después de su almacenaje durante 4 meses. Las semillas de algodón se han recubierto con una película utilizando distintas dosis de ZnSO4 (hasta 11,6 g/kg de semillas) en combinación con un fungicida y un insecticida en una matriz polimérica. La calidad fisiológica antes y después del almacenaje se ha analizado mediante pruebas de germinación y ensayos de primer recuento. En los tests de germinación, aunque las diferencias no han sido estadísticamente significativas, se ha observado que las dosis de 2,9 y 5,8 g de ZnSO4/kg de semillas han mejorado las tasas de germinación, superando el 90%, mientras que dosis más altas (8,65 y 11,6 g de ZnSO4/kg de semillas) han conducido a valores inferiores al control. Las dosis más altas también han producido una reducción del vigor tras 120 días de almacenaje. Respecto a las cuatro isoenzimas cuya actividad se ha medido para evaluar la calidad de las semillas (carboxilesterasa, fosfatasa ácida, glutamato-oxalacetato transaminasa y glutamato deshidrogenasa), se han registrado diferencias para dos enzimas tras 120 días de almacenaje. Los valores más bajos de carboxilesterasa (cuyo aumento va asociado al metabolismo de lípidos y a degeneración de la membrana) y los más altos de glutamato-oxalacetato transaminasa (clave en el metabolismo de las proteínas) se han obtenido para una dosis de ZnSO4 de 5,8 g de ZnSO4/kg de semillas). El estudio sugiere que la aplicación del sulfato de zinc a esta dosis, en forma de composite, mejora la viabilidad de las semillas de algodón durante su almacenaje

Physical and physiological properties of seed corn separated by a gravity table

This study was conducted to evaluate the effectiveness of a gravity table for separating seed corn into fractions of different quality, and to correlate the physical and physiological properties of each fraction of seed corn;Five lots of seed corn with five sizes (unsized, large flat, large round, small flat, and small round) were conditioned through two types of gravity table (pressure and suction type). The original sample, obtained before the gravity table separation, and four fractions (heavy, medium heavy, medium light, and light) obtained from the discharge edge of each gravity table, were analyzed for physical (bulk density, weight of 100 seeds, volume, specific gravity, terminal velocity, purity, breakage susceptibility, and pericarp injury), physiological (standard germination, cold germination, conductivity, and field emergence), and chemical composition (NIR protein, oil, and starch contents);Both gravity tables performed similarly as determined by the seed quality of various fractions. Flat seed corn was better in seed quality than round seed corn. The gravity table was efficient in separating seed corn into fractions of different quality along the discharge edge of the gravity table deck. However, when the initial seed quality of a lot is high, only marginal improvement in seed quality was obtained. The light seed obtained from the low side of the gravity table did not meet the seed requirement and must be discarded. The medium light fraction may be re-conditioned to recover fractions of acceptable seed quality. Bulk density was the best physical property of the seed corn correlated with the physiological quality of the seed. Weight of 100 seed may be also used, but bulk density is preferable due to its higher relationship with field emergence than seed weight.</p

Atributos de qualidade de sementes de milho beneficiadas em mesa de gravidade

Os objetivos deste trabalho foram de avaliar a eficiência da mesa de gravidade em separar sementes de milho em frações de qualidade diferente e de relacionar atributos físicos e fisiológicos das sementes para recomendações práticas de operação. Cinco lotes de sementes de milho classificados em não classificado, redondo grande, redondo pequeno, chato grande e chato pequeno foram beneficiados na mesa de gravidade. A amostra original e as frações pesada, meio-pesada, meio-leve e leve obtidas no terminal de descarga da máquina foram analisadas quanto a atributos físicos (peso volumétrico, peso, volume, densidade, pureza e danos mecânicos) e fisiológicos (germinação padrão, germinação a frio e emergência a campo) das sementes. A mesa de gravidade foi eficiente em separar as sementes de milho em frações de qualidade diferente, sendo as frações pesada e meio-pesada melhores do que a semente original. Para lotes de qualidade inicial alta, somente aumentos marginais de qualidade foram obtidos. O peso volumétrico foi o atributo que relacionou bem com germinação da semente de milho. Recomenda-se o “teste da caneca” para determinar a eficiência das regulagens na mesa de gravidade. Uma diferença mínima em peso volumétrico de 8% entre as frações extremas é recomendada para efeitos de controle de qualidade na mesa de gravidade.This article is from Revista Brasileira de Sementes 13 (1991): 91–97. Posted with permission.</p