Inhibition of ethylene production by osmotic shock. Further evidence for membrane control of ethylene production

Effects of osmotic shock applied to mung bean hypocotyl segments were examined to see if auxin-induced ethylene production is regulated by membrane activity. Uptake of α-aminoisobutyric acid was significantly inhibited by osmotic shock. While cold shock alone also inhibited the uptake, cold osmotic shock was most effective. Auxin-induced ethylene production by the osmotically shocked tissue was similarly inhibited. Shock treatment of auxin-pretreated tissue also suppressed the subsequent ethylene production. Oxygen uptake was not affected by the shock treatment. Sorbitol and sucrose used as osmotic substance were as effective as mannitol. The results suggest that ethylene production is controlled by membrane activity.