Next, with a scalpel, seeds were longitudinally and medially cut, with the endosperm portion containing the embryo placed in 50 mL plastic cups and immersed in a solution of 2,3,5 triphenyl tetrazolium chloride at four concentrations of 0.075; 0.1; 0.5 and 1.0% for three coloration periods (2, 4 and 6 hours) in a chamber regulated at a temperature of 30 o C and the other one at 35 °C in the dark. Four replications of 25 seeds were used for each concentration combination of the tetrazolium solution and coloration period for experiments involving the incubation temperatures.