Increasing production of ethylene from cotton leaves with increasing 2,4-D concentrations (0, 5, 25 and 50 ppm) and also with advance of time intervals of gas collection (0–12, 12–24, 24–36 and 36–48 hours) was noticed. Among the antidotes, Ca (No2)2 treated leaves produced same amount of ethylene as that of control at first interval and in advancing intervals it was much lesser than the control. The effect of GA to reduce ethylene production was slow as it equalled the control value after 24–36 hours whereas, riboflavin and CaCO3 showed gradual reduction with time intervals but it was much higher than the control.
