01731naa a2200217 a 450000100080000000500110000800800410001902200140006010000210007424500530009526000090014852011860015765000110134365000130135465000130136765000160138065000150139665000290141170000180144077300550145816327092023-04-28       1993    bl uuuu     u00u1 u    #d  a0004-82831 aCOELHO, Y. da S.  aFruit thinning in citrus.h[electronic resource]  c1993  aSeveral citrus species have a tendency to produce small-sized fruits aswell as alternate cropping. this results from excessive fruit settingcausing a weakening or even collapse of the plant. In Brazil this problem is frequent in highly productive cultivars such as the Murcott tangor and the mandarins. In an advanced state of pauperization, the plant loses its turgidity, the leaves turn yellow, the branches become defoliated and the fruit and leaves drp and the tree appears dead. fruit thinning is a practice which aims to reduce the excess at particular period, thus favouring stability of production whth increased size and commercial value of the product. It is generally agreed that, in order to control the negative effects of excess production, elimination s hould be of a minimum of 50 to 60% of normal fruiting, leaving one or two fruits on branches with four or five. Because of the high cost of the practice, when done manually, the effects have been studied in various countries of different abscission promoting products such as ethephon. This article discusses the objectives of thinning, the physiological aspects involved and the efficiency if growth regulators.  aCitrus  aethephon  aComercio  aMaturação  aProdução  aRegulador de Crescimento1 aMEDINA, V. M.  tAustralian Citrus Newsgv.69, p.10-12, July, 1993.