FRUIT THINNING AND FRUIT SIZE ENHANCEMENT WITH 6-BENZYLADENINE APPLICATION TO 'WILLIAMS' PEAR
The effect of a single application of 6-benzyladenine (BA) at 10 to 13 mm average fruit diameter on fruit thinning and fruit size in Williams pear trees was evaluated in the Rio Negro Valley of Argentina and the Rogue River Valley of Oregon, USA. BA was applied as MaxCel (Valent BioSciences). In Argentina, applications were made in two orchards in November, 2008 using BA rates of 100 and 150 ml L-1. In Oregon, applications were made in a single orchard in April in each of three years (2007-2009), using BA at 125 ml L-1. In Argentina, BA applications at either 100 or 150 ml L-1 significantly reduced fruit set. Crop load was further adjusted by manual thinning to remove small fruit in all treatments. The number of fruit that needed to be removed manually and the time required for manual thinning were reduced by BA treatments as compared to the control treatment (manually thinned only). Treatments with both rates of BA resulted in significantly increased average fruit size and yield of large-sized fruit per hectare as compared to the control. In one orchard, the largest fruit size was in the BA 100 ml L-1 treatment, while in the other orchard the largest fruit size was in the BA 150 ml L-1 treatment. In Oregon, no manual crop load adjustment was performed, and control trees were unthinned. BA 125 ml L-1 treatment significantly decreased fruit set and increased average fruit weight, while increasing the yield per hectare of large-sized fruit (>211 g individual fruit weight) over the three years of evaluation.
Dussi, M.C. and Sugar, D. (2011). FRUIT THINNING AND FRUIT SIZE ENHANCEMENT WITH 6-BENZYLADENINE APPLICATION TO 'WILLIAMS' PEAR. Acta Hortic. 909, 403-407
Pyrus communis, chemical thinning, manual thinning