THE RELEVANCE OF POLYAMINE LEVELS IN CHERIMOYA (ANNONA-CHERIMOLA MILL) FRUIT RIPENING

Free polyamine levels were determined in cherimoya (Annona cherimola M ill. cv. <Fino de Jete>) fruit during ripening at 20 degrees C. Severa l parameters including respiration rate, ethylene production and total titratable acidity were analyzed. The polyamine prevailing after harv est was spermidine, although a sharp increase was observed in putresci ne content during ripening. The possible relationship between this ris e in putrescine level and the ripening process was studied on the basi s of the pattern of diamine content in fruit stored over a range of lo w temperatures (10, 8 and 6 degrees C). Retardation of the ripening pr ocess by cold storage was concurrent with a slower rate of increase in the free putrescine level. Moreover, where ripening was inhibited by storage at the chilling temperature (6 degrees C), no increase in free putrescine was observed. While no variation was observed in spermidin e and spermine content in fruit ripening at 20 degrees C, levels did u ndergo change during low temperature storage. The possibility that sig nificant accumulation of the free putrescine titer may be associated w ith high acidity levels in ripening cherimoya tissues is discussed.