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The aim of this study was adapting the methodology of the accelerated aging test (AA) and electrical conductivity test (EC) to evaluate seed quality of crambe, as well as verifying enzymatic activity in relation to vigor differences. Crambe seed lots, cv. FMS Brilhante, were evaluated by the AA test, for periods of 0, 24, 48, 72 and 96 h, at 42 °C, with and without NaCl saturated solution; and the EC test, by soaking seeds into deionized water (mL) in the ratios of 25/25, 25/50, 50/50 and 50/75 (seed/water) for 2, 4, 6, 8, 10, 12, 14, 16 and 18 h. The electrophoretic profile for isozymes esterase, superoxide dismutase, catalase, isocitrate lyase, alcohol dehydrogenase and malate dehydrogenase was evaluated on polyacrylamide gel (7.5%). The AA test conducted at 42 °C, for 96 h, was efficient to detect differences on seed quality levels; however, the EC test was not suitable to evaluate vigor of those seeds. The bands stained for isozymes esterase, superoxide dismutase and catalase were evident for the more vigorous seeds; and the bands for isozymes isocitrate lyase and alcohol dehydrogenase were less evident for the less vigorous seeds. For enzyme malate dehydrogenase enzyme intensity of bands was similar.

Abstract:Sunflower crops (Helianthus annuus L.) are a source of pathogens that can be transmitted by means of the seeds. An alternative for the treatment of seeds can be the application of an ozone compound, which has been used in various segments to eliminate microorganisms. Three lots of the Embrapa 122 variety have been used to assess the efficacy of ozone to control pathogens in sunflowers seeds. To typify the profile of the lots we have determined the moisture content, the first germination counting, the germination, the germination speed index, emergence, initial stand, emergence speed index and health. The lots have been stored in an ozone-rich environment for periods of 20, 60 and 120 minutes and without ozone (control). After the treatments, the seeds were tested to assess their health and physiological quality through the said tests as well as a test for accelerating aging, tetrazolium and incidence and severity of fungi. It has been concluded that the treatment for H. annuus seeds, Embrapa 122 variety, with ozone concentration of 1741 ppmv (0.24 g/h), for 60 minutes, reduces the fungal presence of Alternaria sp., Fusarium sp., Aspergillus sp. and Penicillium sp. without affecting their physiological potential.

ResumoO teste do tetrazólio é considerado uma alternativa promissora para a avaliação rápida da viabilidade e vigor das sementes. A adequação da metodologia do teste de tetrazólio para sementes de crambe, espécie que apresenta alto potencial para produção de biodiesel, pode acelerar a determinação da qualidade de diferentes lotes. Com o objetivo de verificar as condições ideais para realização do teste de tetrazólio em sementes de crambe cinco lotes da variedade FMS Brilhante foram submetidos à embebição entre papel em água a 30°C por 3 horas e após corte longitudinal as sementes foram imersas nas concentrações de 0,075%; 0,5% e 1% de solução de tetrazólio a 30°C por 18 h e 24 h. Observou-se que na concentração de 0,075% as sementes coloriram adequadamente e com 0,5% e 1,0% a coloração foi intensa. A embebição das sementes entre papel por 3 horas, seguida de corte longitudinal e utilização de 0,075% por 18 h ou 24 h é eficiente para avaliação da viabilidade das sementes de crambe. Palavras-chave: Crambe abyssinica, viabilidade, pré-condicionamento AbstractThe tetrazolium test is considered a promising alternative for quick evaluation of viability and vigor of seeds. The adequatio of tetrazolium test methodology for crambe seeds, specie that presents high potential for biodiesel production, may accelerate the determination of quality of different lots. With the aim to verify the ideal conditions for the tetrazolium test for crambe seeds, five lots of cultivar FMS Brilhante were submitted to the imbibition between paper in water at 30°C for three hours and after the longitudinal slicing, seeds were soaked in tetrazolium solution at concentrations of 0.075%; 0.5% and 1.0% at 30°C for 18 h and 24 h. It was observed that in the concentration of 0.75% seeds got an adequate coloration and with 0.5% and 1.0% the coloration was too intense. The imbibition of seeds between paper for 3 hours, followed by the longitudinal slicing and the utilization of 0.075% concentration for 18h or 24 hours was efficient to the evaluation of viability of crambe seeds.