Teste de tetrazólio em sementes de crambe

Abstract

The tetrazolium test is a useful alternative for seed viability and vigor evaluation because besides producing rapid results it can also identify the causes of lost viability. This test is recommended for the evaluation of the viability of seeds that have to be sown soon after harvest and also complements germination tests for seeds that present dormancy. For each species, the efficiency of the tetrazolium test depends on the development of appropriate methodology that includes appropriate methods for pre-conditioning, preparation and staining of the seeds. We evaluated preparation and staining methods for applying the tetrazolium test to leucaena seeds and verified the efficiency of this test for assessing the viability of leucaena seeds using seeds from Leucaena leucocephala cv. Cunningham and the interspecific hybrid (L. leucocephala x diversifolia CPAC 4111. Two seed preparation methods were tested, a lateral cut and a lateral cut followed by immersion in water for one hour at 30 °C and subsequent seed coat removal. The seeds were stained with 0.075%, 0.15% or 1% tetrazolium solution for two or four hours at 35°C and then evaluated. The tetrazolium test results were compared with the results of standard germination and seedling emergence tests. Our results show that subjecting the seeds to a lateral cut and seed coat removal and then submersing them in 0.15% tetrazolium solution for two hours is an efficient method for evaluating leucaena seed viability.