The gibberellic acid (GA3) has been studied with particular interest in the posharvest, therefore it improves the quality and it delay the senescence of the fruits through a complex mechanism of signaling, linked to the activity of responsible enzymes for the process of the ripening. This phytohormone, when applied exogenous, it plays an important role in the delay of the activity of enzymes, especially of the cellular wall, in the synthesis of carotene, degradation of chlorophyll and in mangoes the GA3 was responsible for decrease the activity of amylases and peroxidases. The banana, climacteric fruit, have as main power plant the starch. The starch of banana, depending of the variety, is reduced during the climaterium of value that vary of 12 the 20% to less than 1%, when the fruit is ripened, and the sacharose can increase up to 12 fold, in this time. In hydrolysis of the starch, the amylases seems to play a basic role in the beginning of this degradation, therefore it is given credit that only endoamylases is capable to attack entire granules, supplying substratum performance of other enzymes until the formation of sugars. The aim of this employment was to evaluate the effect of the giberelin A3 in the ripening of the banana, focusing the degradation of the starch. It was observed that the infiltrated phytohormone did not be under influence of the respiratory climacteric, however delayed the degradation of the starch and the accumulation of soluble sugars in at least two days and the peak of total activity of amylases also it was been slow.
banana; ripening; gibberellic acid; amylases
