Growth and Yields of 'Arbequina' High-Density Planting Systems in Three Different Olive Growing Areas in Italy

The sustainability of the traditional olive-growing sector in EU countries characterised by high production costs and a low selling price for the oil - was mainly determined by EU subsidies available for the sector. With the opening of the "free trade" area by the Barcellona Declaration of 1995 and a cut in EU subsidies in 2014, crucial changes in the sector are now needed. In order to increase the competitiveness of EU olive production, attention should be given to new high-yielding and mechanized cultivation systems. In the 1990s, Spain introduced new high-density planting systems (1,200-2,000 trees/ha) using three low-vigour and early-fruiting cultivars ('Arbequina', 'Arbosana' and 'Koroneiki'). Italian olive production lies in a geographical area that stretches for about 6 degrees in latitude (37-43 degrees latitude N) and in the band of altitude which ranges from sea level to 400 m a.s.l. Studies on the ecophysiology of woody plants show the importance of adapting the planting system to the climate of the cultivation site, particularly for high-density groves. The evaluation of cultivars suitable for high-density systems, based on their vegetative characteristics, branching and fruiting, together with an analysis of product quality, may contribute significantly to the development and diffusion of new crop growing systems. To achieve this aim, joint research was carried out by three different research units operating in the three main olive-growing regions of Italy (Sicily, Apulia and Umbria). This paper illustrates the first results (2010 and 2011) obtained by the PRIN Project on "Biological processes and environmental factors affecting the vegetative growth, fruiting and oil quality control in a high density olive (Olea europaea L.) planting system".