02113naa a2200169 a 450000100080000000500110000800800410001910000110006024500810007126000090015252015980016165300180175965300220177765300150179965300230181477301060183710784002011-07-18       2010    bl uuuu     u00u1 u    #d1 aEpagri  aChemical Thinning After Blooming in Apples in Southern Brazilian Conditions.  c2010  aThe thinning is still a major technologic problem in the apple production in Brazil, mainly due to the weather instability. ?Gala? apples and its clones have an intense blooming in axillary buds and under adverse conditions during the pollination may have a low fruit set, which prevents the thinning at blooming by producer. ?Fuji? apples show high fruit set levels, but this cultivar has predisposition to alternate production. Thinning substances like naphthalene acetic acid (NAA), carbaryl, ethephon and benzyladenine (BA) were sprayed alone or in mixture after blooming of ?Gala? and ?Fuji? apples, during three years. The evaluations were fruit set (%), number of fruits per tree and number of fruits per cross trunk sectional area, mean fruit weight (g) and fruit distribution according fruit size. Applications of NAA 10 mg.L-1 at 5 days after full bloom (DAFB) plus Maxcel?? 2 L.ha-1 sprayed in fruits with diameter of 5-8 mm, and NAA 10 mg.L-1 + Maxcel?? 2 L.ha-1 sprayed in fruits with diameter of 5-8 mm increased significantly the mean fruit weight of ?Gala? apples. The applications of NAA 15 mg.L-1 at 5 DAFB + Maxcel?? 4 L.ha-1 and NAA 15 mg.L-1 at 5 DAFB + (ANA 15 mg.L-1 + Maxcel?? 4 L.ha-1) in fruits with 5-8 mm were effective on increasing of mean fruit weight in ?Fuji? apples, but increased the number of small fruits with reduced growth . The replacement of NAA 15 mg.L-1 by Carbaryl at 1000 mg.L-1 also reveals efficient. The mixture of Carbaryl 1000 mg.L-1 plus Maxcel?? 6 L.ha-1 increased the thinning efficiency when sprayed in fruits with diameter above of 10 mm.  aConcentration  aGrowth regulators  an Thinning  aTime of aplication  tIn: INTERNATIONAL HORTICULTURAL CONGRESS, 28., 2010, Lisboa. Book of Abstracts... Lisboa: ISHS, 2010.