Abstract:
Tree vigour is one of the most important issues in
super-high density olive orchards
(~1,600 tree ha
-1
). Tree vigour could be limited by horticultural pr
actices such as pruning
and fertilization but such practices have a limited
effect and increase growing costs. The
aim of this work was to test a new technique based
on the application of a constriction to
the trunk in order to obstruct the flow of sap in x
ylem and phloem. To this end, on 5
cultivars trained in a super-high density olive orc
hard in Central Italy, constrictions were
applied by a plastic strap in 2009 and 2010, and we
re removed at the end of the following
year. At the end of the experiment, constricted tre
es had smaller vegetative growth than
the control trees. During the first experiment (200
9), in the constriction year, yield
efficiency was higher in constricted trees. In the
second year, low vigour cultivars
(‘Arbequina’, ‘Maurino’ and ‘Moraiolo’) had a consi
stent reduction of yield, while
vigorous cultivars (‘Leccino’ and ‘Frantoio’) had s
imilar yield but a slightly increased
yield efficiency. No effect was detected in fruit c
haracteristics, but the oil phenol content
was higher in the constricted trees. In the second
year experiment (2010), similar results
were obtained, but yield efficiency increase and ve
getative growth reduction were lighter
because the trees were one year older than those of
2009 experiment. Trunk constriction
was a successful technique for reducing tree vigour
and enhancing tree yield efficiency,
especially in vigorous cultivars.
Keywords
: Arbequina, Hedgerow,
Productivity, Wiring.
