01708naa a2200181 a 450000100080000000500110000800800410001910000210006024500650008126000090014652012170015565000150137265000140138765000200140170000150142170000200143677300700145616468541995-08-25       1977    bl ---       0--  u    #d1 aGUARDIOLA, J. L.  aGibberellic acid and flower bud development in sweet orange.  c1977  aGibberellic acid sprays reduced flowering of `Washington' navel and `Navelate' oranges, the degree of reduction depending on time of application and the concentration. Although the greatest affect of GA was obtained when applications were made during the time of flower induction, its main action does not appear to be related to an inhibition of this process as reported earlier since: I.- The number of flowers per inflorescence was not affected, and: II.- The increase in the proportion of leafy inflorescences and vegetative sprouts was mainly due to a marked reduction in the number of leafless inflorescences, most of the corresponding buds failing to develop and not severting to a vegetative apex nor to a more leafy inflorescence. It is our conclusion, therefore, that the main effect of GA lies in the inhibition of bud development before visible growth starts in spring, the buds of the leafless inflorescences being more sensitive to this compound. No effect was observed in the abscision of sprouts, which was e even lower in the GA-treated trees in which the decrease in their number reduces competition during early growth, as shown by a more vigorous growth of both flowers and vegetative shoots.  afruit drop  afruit set  aCitrus Sinensis1 aAGUSTI, M.1 aGARCIA-MARI, F.  tReprinted from Proc. Int. Soc. Citriculturegv.2, p.696-699, 1977