STUDY ON THE RELATIONSHIP BETWEEN THE ACTIVITY OF PHOSPHOLIPASE, MEMBRANE PERMEABILITY AND THE ETHYLENE RELEASE DURING RIPENING OF BANANA FRUITS
Jiao Xinzhi Qiu Hongbin Li Lin ( Shanghai Institute of plant Physiology, Academia Sinica ) Jiang Jianping ( Southern China Agricultural College )
During the repining of banana fruits the ethylene released by peel is earlier than that by pulp tissue, and the first change is the phospholi-pase activity rising proceeding has a peak shape and the subsequent or-der is by enhancing the membrane permeability, ethylene release and re-spiratory climacteric. The effects of ACC promotion and CCCP inhibition on ethylene released by banana fruits indicate that ethylene production is by Methionine-Path. CEPA, AOA and CCCP can change the sequence of enhancing cell membrane permeability and ethylene release. CEPA can move up the time of enhancing the membrane permeability almost to the occurrence of ethylene release. The time of enhancing of membrane permeability is de-ferred by AOA and CCCP to come after the appearance of ethylene re-lease peak. It dose not seem that causal relationship exists between the two. 1mM ACC can activate the ethylene bio-synthesis mechanism in un-ripening banana peel and pulp tissues. The inhibitory action of CCCP on ethylene released by CEPA shows that the change from CEPA to ethy-lene is an enzymolysis process. CCCP exerts different inhibitory effect on ethylene release induced by ACC and CEPA, suggesting that the two have different path of enzymolysis. CCCP can not completely inhibit the ethylene release induced by CEPA.Probably the uninhibited part of the ethylene released by CEPA (up to about 20%) is by non-enzymolysis path.