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Although the olive (Olea europaea sativa l.) is considered a xerophytic species, long periods of water stress and high temperatures during summer months can greatly affect plant physiology and productivity. In recent years, the use of plant-based water status indicators have become popular in the study of plant-water relationships and in the design of irrigation programs, particularly midday stem water potential (ψstem). The current trend in the irrigation of olive trees is in the development of Deficit Irrigation (DI) systems whereby the water is applied at a rate which is lower than evapotranspiration needs, resulting in only very small reductions in yield. Rather than working towards minimizing crop water deficits, an irrigation manager must decide on what level of deficit to allow and must recognize when that level has been reached. Traditionally, olive trees in Sicily are not watered, with the exception of those destined for the table olive industry. Considering the growth of the table olive industry in Sicily, the choice of a correct irrigation management related to the olive tree stress threshold is necessary in order to save water. In the Belice Valley, where the table olive cultivar Nocellara del Belice is cultivated, irrigation is still managed traditionally, with a high level of variability and water waste. This trial, conducted in two consecutive olive crop seasons (2010 and 2011) aimed to evaluate the effects of deficit irrigation management on tree physiology, yield and fruit quality of the table olive cultivar Nocellara del Belice.

The influence of flesh firmness on consumer acceptance and its relationship with total soluble solids concentration (TSSC), titratable acidity (TTA) and sensory analysis was studied to understand their interaction in determining acceptance judgments, for different organoleptic typologies of peaches and nectarines. The investigation was carried out during summer 2006 on fruit of ‘September Sun’ and ‘Sweet September’ (low acid) peach (Prunus persica (L.) Batsch), and ‘Maria Dolce’ (low acid) and ‘Venus’ nectarines (Prunus persica (L.) Batsch, var. nucipersica). Sensory descriptors for peaches and nectarines were Flesh firmness, Sweetness, Sourness, Aroma, and Acceptability. The panel was able to discriminate different fruit ripening stages, in terms of fruit firmness, aroma and sweetness and to relate those parameters to fruit acceptability. ‘Maria Dolce’, ‘Venus’ and ‘September Sun’ fruit ranging from 3.2 to 5.3 kg cm–2 of flesh firmness, were accepted by the panel, while acceptability of low-acid fruit of ‘Sweet September’ was related to their aroma and firmness. Values of flesh firmness higher than 5.5 kg cm–2 always resulted in unacceptable fruit quality.

In peach industry, due to the increasing cost of the land, energy and salaries, in the last thirty years have been developed horticultural strategies to increase the productivity of the orchards and to reduce the employment of hand workers. In areas in which large part of the days are brilliant, clean sky, with high levels of light intensity, and relative humidity is low, as those with a Mediterranean climate, to reach the above mentioned goal have been developed planting systems based on high tree densities and new tree shapes. In Southern Italy, technicians have been particularly active in performing new tree canopy architectures and growers showed to be very sensitive to these innovations as evidenced from the replacement of the traditional open vase with “inclined double walls” systems Y, V and Tatura trellis. These new planting systems, respect to those based on the “open vase“ allowed to obtain higher yield together with a larger amount of top quality fruits and this as consequence of the increased amount of light intercepted and more uniformly distributed within the tree. In this last decade, the increasing costs of the trellis components (iron wires and poles) to build up the trellis and the costs of the trees, due to the royalties protecting the new released cultivars, became the major limits of this super-intensive planting systems. For this reasons, despite the high efficiency of the workers in practicing the manual techniques (fruit thinning, harvest and pruning) the “inclined double walls” started to be abandoned and technicians and growers start to move to the catalan vase. This new system has been develop recently in Spain, being a new tree shape, a dwarfed vase named catalano, that complies relative high density with low cost for orchard planting and management. This training system, to control vegetative excessive growth , is based on several treatments of topping, some of them, particularly during the summer season, are performed mechanically. Preliminary observations carried out in Sibari, seem to confirm that the vasetto catalano - even managed without treatments with paclobutrazol, a growth retardant, as used in Spain, - could represent a valid planting system to produce both fruit for the fresh and for the processed (fresh cut, sliced fruits) fruits market. In greenhouse production, where precocious and high yield are the required conditions to have early return, planting systems have to be based on tree shapes that fit with high densities, as Y and V, currently the only one able to provide fruit of optimal quality for out-of-season peaches market. In California, although a certain agronomic success has been obtained by the KAC V, the “inclined double wall “systems were unsuccessful. Other shapes as “Quad V” and “Hex-V” , that are a sort of compromise between the perpendicular “V” system and the traditional open vase, have been developed in order to address some of the vigor issue inherent in the two scaffold perpendicular system as well as to reduce planting densities and orchard establishment cost. Scientist and field technicians are still searching for the molecule for fruit thinning and to build up the right machine for harvesting trees trained to open vase. Unfortunately, so far, only summer pruning mechanization has been developed. In Chile most of the information necessary to develop the important advances of fruit industry occurred in the last 25 years have been introduced or adapted from abroad. Peach orchards have been steadily intensified, predominantly using denser orchards with refined form of the open vase system, with the perpendicular V or three arm trees currently being the most common system. Generally, tree size reduction has been one of the main objective of breeders by searching for compact and brachitic vegetative habitus and for dwarfing rootstocks but no satisfactory genotypes has been selected yet and this last still remain a potential tool for high density planting systems. The researches on the use of chemical agents able to control vegetative growth were abandoned in many Countries because the environmentalist movements hardly contrasted such kind of solution. However, rational irrigation, mineral nutrition and soil management (controlled water stress, fertirrigation according to phenologic tree phase and real absorption, cover crops) could contribute to improve planting systems, controlling the vigor trees in orchard.

Una costante attenzione verso l’ottimizzazione dei fattori della produzione ha determinato una rapida adozione delle innovazioni proposte dalla ricerca nel campo dei sistemi d’impianto, per la grande importanza che essi rivestono nella qualità delle produzioni e nella redditività della coltura. Riduzione dei costi di produzione e massima efficienza della manodopera gli obiettivi prioritari, talora ottenuti attraverso l''“estensivizzazione” colturale, con bassi costi d’investimento. Un confronto fra l’Italia meridionale, California e Cile.