High-density oliveculture system needs irrigation and introduces new cultivars in new environ-ments. So the evaluation of varietal ecophysiological response to irrigation is a crucial topic. For this reason it was planned a research on two cultivars, Coratina and Arbequina, trained according to high-density system. In 2009 the irrigation was conducted according to the conventional man-agement by applying an irrigation frequency of 4 days. The leaf water potentials reached values similar to the limits reported for the recovery within 48 hours. However, plants showed a leaf wa-ter status and gas exchange recovery just after 24 hours from watering. The results highlighted some varietal differences: Arbequina showed a better response to irrigation, while Coratina per-formed an higher water use efficiency by a lower leaf transpiration.

Abscisic acid (ABA) is associated with regulating plant adaptive responses to various environmental stresses. In particular, drought stress signals are transmitted through at least two pathways: one is abscisic acid (ABA)-dependent, and the other is ABA-independent. In the first case, drought stress increases the cellular ABA levels, which induces the expression of drought stress-responsive genes, such as 9-cisepoxycarotenoid dioxygenase (NCED) and zeaxanthin epoxidase (ZEP). These genes belong to the carotenoid biosynthesis scenario. To date, most research of grapevines has focused on the physiological mechanisms of ABA during fruit ripening. Our interest is on studying the role of NCED and ZEP genes as candidate genes exhibiting up-regulation upon drought-stressed conditions. At the same time, several plant physiological parameters, such as leaf water status (ψl), net assimilation rate (A), stomatal conductance (gs), transpiration rate (E), and soil water potential (ψs), were monitored. To explain the complex molecular pattern undergoing these physiological changes, we investigated the levels of expression of one candidate gene encoding for VvNCED1. The results provided evidence of a different transcriptional pattern of the gene between the control and stressed plants, leading to a major accumulation of NCED1 transcripts in the stressed plants.

The prevailing environmental conditions, temperature in particular, drive seasonal changes both in leaf development and stomata! characteristics. In order to ascertain the effect of increases in climatic water deficit on some leaf and stomatal parameters under field conditions, a study was carried out on two sets of leaves (spring and summer) on a large sample of Amygdalus communis L. cultivars in comparison with several Amygdalus webbii Spach seedlings, a species more adapted to arid environments and probable ancestor of cultivated almonds. Observations were performed between spring and summer of a particularly hot season. The results showed a significant and general reduction of both leaf area and stomatal frequency and an increase in stomata! size. Nevertheless, there were evident differences between cultivated and wild almonds. A stronger reduction of leaf area was observed in A. webbii (-31%) with respect to A. communis (-14%); on the contrary, the latter reduced stomatal frequency more than the former (-25% and -19%, respectively). The examined cultivated almonds, in response to the increase in climatic water deficit, tended to arrange their stomatal structures like those of wild almonds. Finally, increasing the climatic water deficit, the slope of the linear regressions between stomatal frequency and size did not change in either species, leading to a better understanding of the mechanisms of almond acclimation to environmental stresses.

Recent olive cultivation in Mediterranean Countries is characterised by the strong diffusion of high-density cropping systems and by the most environmentally conscious management regarding all the agronomic practices and the waste disposal as well. This research has investigated the possibility of the use of De-Oiled Pomace (DOP) as an eco-friendly tool for weed control in a high-density olive orchard providing an environmental comparison with other soil management techniques. Five methods of weed control have been compared in a two-year experimental orchard at the Bari University (Southern Italy): mulching with de-oiled olive pomace (DOP), nonwoven tissue (TNT) and polyethylene film (PEN), chemical (CHI) and mechanical (MEC) weeding, on the three most adapted to high-density orchards olive cultivars (Arbequina, Arbosana and Koroneiki). The data collected during the experimental test are submitted to an LCA (Life Cycle Assessment) analysis and five scenarios have been drafted based on DOP use and destinations. The results showed that the chemical wedding produced the greatest environmental burdens, and the higher environmental performances of DOP mulching scenarios for all environmental indexes, with burdens reductions and/or environmental credits. The presence in the following years of some biomarkers sensitive to macro and micro pollutants and heavy metals, in experimental plots mulched with DOP, confirmed the high environmental sustainability of this technique, excluding any kind of soil pollution in the medium-term period in the high-density olive orchard.

This research was performed in order to assess the microbiological impact of three different sources of treated municipal wastewater on the tree-soil system of a nectarine orchard. Wastewaters coming from two different tertiary treatment processes [conventional tertiary water (TW) and lagoon simplified tertiary water (LW)] and a secondary treatment process (SW) were compared with fresh water (FW). A two-year field experiment (2011 and 2012) was carried out monitoring Total Coliforms, Fecal Coliforms, E. coli and Salmonella spp. concentrations on source waters, root zone soil and fruits. The microbial concentration mainly depended on the treatment system of the source water but in most cases it was always over the current Italian threshold (10 CFU 100 mL−1; D. No. 152/2006). In general, the SW showed the highest level of contamination for both years followed by LW, TW and FW. Although soil plots irrigated with the SW were heavily contaminated as expected, nevertheless the soil was able to greatly reduce of 2.6 log10 CFU 100 g−1 the fecal contamination. The soils irrigated with LW, TW and FW showed a lower fecal bacteria contamination. Total Coliforms were confirmed as ubiquitous in this agricultural environment and contamination by E. coli on fruits surfaces was not negligible when plots were irrigated with SW for both years. This study supports the hypothesis that very low quality of irrigation waters cannot be used safely in a nectarine orchard because it represents a risk for human infection

Three-year observations about the canopy restraining of 15 olive cultivars trained according to the high-density system were made in order to supply up-to-date information about the varietal behavior foradult orchards of this new cropping system. The mechanical pruning started at the end of the 6th year from planting and it was repeated for the following two years. Cultivar vigour affected pruning biomassand olive yield. Canonical discriminant analysis was performed to identify differences among cultivars. Medium-low vigour cultivars (Spanish and Greek) can be successfully controlled by mechanical and manual prunings without compromising their yield; instead, medium-high vigour cultivars (traditional and new Italian) require mechanical prunings to control canopy size, but this operation can hardly compromise their yield level and constancy. Further investigations are required to understand the right width ofhedging to reach the correct equilibrium between vegetative and reproductive activity in adult orchards. At the moment, the correct varietal choice remains the only way to ensure the agronomical and economic sustainability of the high-density cropping systems, waiting for new results from breeding programs.

The new high-density cropping systems (> 1,200 trees ha-1) represent a very interesting proposal for olive orchard profitability. It is crucial to know the morphology and the dynamics of sprout elongation of a cultivar in order to fully assess its suitability for a high-density olive orchard. For this reason we planned a research on two cultivars, Coratina and Arbequina, in a high-density or-chard. The apical sprouts elongation of Arbequina early stopped at fruit set without a further step, while Coratina showed a little growth flux after pit hardening. Similar trends showed the lateral proleptic sprouts. Only the sylleptic sprouts of both cultivars had a second period of activity. In all cases, the sprouts elongation finished at the end of summer, when oil accumulation started. Co-ratina showed higher apical shoot growth and internodes mean length than Arbequina. On the contrary, Coratina showed lower lateral proleptic shoot growth and nodes number than Arbe-quina, but the same internodes mean length. No significant differences were observed between cultivars for growth, nodes number and internodes mean length of sylleptic shoots. The differ-ences observed between the two cultivars could be explained considering their different vigour. The introduction of this innovative cropping system allowed to register a considerable reduction of production costs. The result is a considerable increase in the economic performance of the olive grove and a consequent reduction in the unit cost for kg of oil. These data are very useful for varietal choice and field management in high-density orchards and then for new olive breeding programs.

La cultivar OA10 possiede peculiari caratteristiche vegetative e riproduttive che la rendono adatta all’olivicoltura superintensiva: vigoria medio-bassa; portamento eretto e chioma di buona densità; entrata in produzione precoce; ginosterilità bassa; allegagione alta; pezzatura dei frutti buona; produttività per albero elevata; danni ai frutti da raccolta meccanica bassi; danni ai rami limitati; sensibilità alla mosca medio-bassa. L’epoca di raccolta ottimale è quella corrispondente al 50% dell’epicarpo invaiato. Ciò cade negli areali pugliesi tra la seconda decade di novembre e la prima di dicembre. In questa fase di maturazione i frutti posseggono: buona consistenza della polpa che riduce i danni da raccolta meccanica; pezzatura ed indice di caduta che consentono alte efficienze di raccolta meccanica; rese in olio ottimali. L’olio di OA10, estratto in questa epoca di raccolta, possiede ottime caratteristiche chimiche e sensoriali. In particolare, l’acidità è intorno a 0,3% e le mediane del fruttato, dell’amaro e del piccante sono alte. Da evidenziare, infine, il buon contenuto di polifenoli dell’olio di OA10. Ciò non solo conferisce ricercati attributi organolettici e allungano la shelf-life degli oli, ma permette di estrarre oli nutraceutici, poiché rientrano pienamente nel claim salutistico dell’EFSA. Miglioramenti e vantaggi rispetto alle tecnologie attuali o alternative OA10 è la prima cultivar con parentale italiano che si possa adattare a pieno ai sistemi colturali ad alta densità, consentendo di ottenere riduzione dell’80% dell’impiego di manodopera agricola specializzata rispetto ai migliori impianti intensivi italiani. La cultivar potrà essere inserita di diritto nei disciplinari di produzione italiani. Pertanto le aziende potranno produrre di olio extra vergine di oliva Made in Italy con una riduzione dei costi del 50% rispetto ai migliori impianti intensivi attualmente in produzione con le cultivar nazionali. Applicazione industriale OA10 è il primo genotipo di origine italiana adatto per la coltivazione dell’olivo in impianti superintensivi che possiede i parametri sia vegetativi che riproduttivi rispondenti al modello richiesto e che produce oli dotati di ottime caratteristiche organolettiche e nutraceutiche.