positive results. Pistillate flower induction and eventual differentiation appears to be influenced both locally (shoot or branch) and at the whole tree level. For instance, fruit removal on an individual shoot positively impacts return bloom of the same
GA 3 in Israel ( Blumenfeld, 1981 ). In addition, there is concern that GA 3 application may reduce return bloom. A decrease in flower initiation in response to GAs has been reported for various fruit species ( Bangerth, 2006 ; Goldschmidt et al
return bloom and consistent cropping. Williams (1979) attributed the increased consistency of U.S. apple production after 1949 to the widespread commercial adoption of chemical thinning technology from that year. However, cultivars that exhibit a strong
Eaton, 1986 ; Strik et al., 1991 ). However, recently released cultivars are reputed to exhibit extensive return bloom ( Roper, 2006 ). Return bloom occurs when a fruiting upright develops a mixed bud, thereby circumventing biennial bearing. Much of the
tree during floral induction ( Plummer et al., 1989 ) and sometimes during anthesis and initial fruit set ( Monselise and Goldschmidt, 1982 ). Delaying harvest in an on-crop year is known to further reduce return bloom ( El-Otmani et al., 2004a
of juice was used for the measurement. Return bloom To investigate the effects of the PGRs on return bloom or the on- and off-year fruiting, the flower bud formation and flower development were investigated after PGRs application in sweet
load can reduce size, color appearance, lower flesh firmness, lower sugars, and acidity of fruits ( Embree et al., 2007 ; Hampson and Kemp, 2003 ) in addition to return bloom the following year. Crop load can also affect the photosynthesis in apple
, 1938 ; Wood, 1989 , 1991 ; Worley, 1979a , 1979b ). Other work suggested that the inhibition of return bloom by developing fruit was incited by phytohormones or other growth regulators ( Amling and Amling, 1983 ; Smith et al., 1986 ; Wood, 2003
-Ca results from one cultivar to another. In the United States, P-Ca (trade-name Apogee ® ; BASF Corp., Research Triangle Park, NC) was initially labeled for use with pear, but substantial reductions in return bloom of ‘Bosc’ ( Sugar et al., 2004 ) and reduced
). There have been many reports on the effectiveness, timing, and rate of ProCa on growth control, fruit set, and return bloom ( Byers and Yoder, 1999 ; Costa et al., 2000 ; Medjdoub et al., 2005 ; Miller, 2002 ). However, these reports are based