ISSN: 2376-0354
Department of Horticultural Sciences, University of Bonn, Bonn, Germany
Research Article
Effect of Crop Load Management by Blossom Thinning or cluster Leaf Removal on Apple Quality and Alternate Bearing
Author(s): Prud Netsawang*, Peter Schulze Lammers, Achim Kunz and Michael Blanke
The influence of Crop Load Management (CLM) on fruit quality, yield, and alternate bearing was assessed by
comparing three methods of modifying the source: sink relationship: a) Mechanical, b) Chemical and c) Manual
thinning. A total of 450 apple trees (Malus domestica Borkh., cv. ‘Roter Boskoop’; six years old) on M9 rootstock at the
Klein-Altendorf field laboratory (50°N) of the university of Bonn, Germany were used. Trees were mechanically
blossom-thinned at the balloon stage (BBCH 59) with a rotor speed of 320 rpm or 380 rpm at 5 km/h tractor speed
or were chemically thinned at full bloom stage (BBCH 65) with Ammonium Thiosulfate (ATS), Ethephon (ETH),
and/or 6-Benzyl Adenine (BA) at 10-12 mm fruit size (BBCH 71) after applying ATS/ETH. Flower clusters and/or
cluster leaves were manually removed to determine the optimum sink-source rat.. View More»
DOI:
10.35248/2376-0354.23.10.001