INFLUENCE OF CHEMICAL GROWTH REGULATION ON SECONDARY BLOSSOM FORMATION ON YOUNG PEAR TREES ‘CONFERENCE’ AND ‘DOYENNE DU COMICE’

The formation of secondary blossoms is typical for young ‘Conference’ pear trees between 2 and 10 years old and determines the host susceptibility of those trees to the bacterial disease fire blight [Erwinia amylovora (Burr.) Winslow et al.]. During the last 2 years, Belgium lost about 100 ha of young ‘Conference’ trees due to fire blight infections on secondary blossoms. In the trial on training systems of young pear trees, we had the opportunity to quantify the formation of secondary blossoms, which was sometimes linked to shoot regrowth from pruning cuts during the season.