Tetrazolium test to evaluate the viability of oil radish seeds

Resumo

The use of tetrazolium test is important in the evaluation of seeds lot quality and it has been adopted for vigor and viability identification for several species. The interest on the production of oil radish is increasing since the seeds were considered a good source of oil for biofuel production. The development of the tetrazolium test methodology for seeds of this species can improve the seed quality control process, and additionally will provide information for the characterization of remaining seeds (dead or dormant) in the germination tests. To verify the ideal conditions to tetrazolium test was conducted two experiments. At the first, oil radish seeds cultivar CATI AL-1000, lots from 2001 and 2006 were submitted to imbibition between paper in water for 6 hours. After the longitudinal cut in the longest direction, the seeds were immersed in the tetrazolium solution at the concentrations of 0,075%, 0,5% and 1% at 25°C for 3h, 12h and 18h. In the second experiment, oil radish seeds cultivar CATI AL-1000 lot from 2005 and IPR 116 cultivar, lots from 2004 and 2005 were immersed in the concentrations of ,1%; 0,2%; 0,3% and 0,4% of tetrazolium solution for 12 hours at a 25°C, 30°C, 35°C and 40°C. At the first experiment was observed the necessity of test intermediate concentrations between 0,075% and 0,5%, since with 0,075% the seeds stained weakly and with 0,5% the test results, were overestimated. In the second experiment was observed that the 0,3% concentration at 30°C can be recommended for the utilization of tetrazolium test to evaluation of oil radish seeds viability.