Rapid Production of Auxin-induced Ethylene

The time course of auxin-induced ethylene production was determined in mesocotyl segments of etiolated sorghum (Sorghum bicolor L. Moench) seedlings. The latent period between addition of auxin and a detectable rise in ethylene release was 15 to 20 minutes in four different genotypes. This may indicate that the initial effect of auxin on ethylene production is too rapid to involve synthesis of an ethylene-producing enzyme. The technique devised for these experiments involves placing tissue segments end to end in a glass tube, and it allows simultaneous determination of growth and ethylene production.