Ethylene biosynthesis enzyme activity of the different tissues. (A) In vitro ACO activity (nmol h-1 mg protein-1) and (B) in vitro ACS activity (nmol h-1 mg protein-1) for the different tomato fruit tissues during fruit development, climacteric ripening and postharvest storage. Error bars represent the standard deviation of 3 biological replicates. M. Medium sized fruit; MG. Mature Green fruit; BR. Breaker fruit; LO. Light Orange fruit; O. Orange fruit; P. Pink fruit; R. Red fruit; RR. Red Ripe fruit; RR + X. Red Ripe fruit + X days of postharvest storage.