Effect of abscisic acid and ethephon on several parameters of ripening in banana fruit tissue

Abstract Treatment of banana fruit slices by vacuum infiltration with 10 −3 M abscisic acid (ABA) stimulates the rise in induced respiration. ABA (10 −5 M) has no significant effect. ABA (10 −3 and 10 −5 M) have no effect on the levels of induced ethylene production initiated by cutting and subsequent recovery. ABA-treated slices (10 −3 M) recover only partially from the induced respiration and show a new increase to reach the levels of the climacteric in banana slices. Ripening is advance by 10 −3 and 10 −5 M ABA compared to controls and the rate of the process is directly related to ABA concentration. Since there is no stimulation of ethylene production by ABA, the advancement of ripening can be directly attributed to this compound. Treatment with 10 and 1000 ppm ethephon produce an increase on induced respiration and ethylene production. The effects are directly related to ethephon concentration and are very pronounced at 1000 ppm. The high respiration rates, above the usual climacteric rates, seem to be related to the high levels of ethylene. Ripening is induced immediately by 1000 ppm ethephon. The autocatalitic effect on ethylene production is more evident with 10 ppm which also advance ripening.