The object of this study was to establish parameters to evaluate the physiological quality of castor bean seeds (Ricinus communis L.) using the the tetrazolium test. Five seed lots were evaluated for viability and vigor by the tetrazolium test and the results compared with the germination test in sand, on paper, first count of the germination test on paper, seedling emergence in the field, emergence speed index, seedling vigor classification, seedling length and dry matter, and accelerated ageing. The statistical design was completely randomized and the comparison of means was by the Tukey test at the 0.05 level of probability. The tetrazolium test viability results were correlated with the germination test in sand, with seedling emergence in the field and with seedling length, and tetrazolium vigor was correlated with seedling vigor classification. It was concluded that the parameters established are efficient for estimating castor bean seed viability and are promising for evaluating castor bean seed vigor using the tetrazolium test.
viability; vigor; castor seed; methodology
