Search results for "Olive trees"
showing 10 items of 34 documents
Modelling eco-physiological response of table olive trees (Olea europaea L.) to soil water deficit conditions
2013
Abstract The knowledge of crop response to water stress is crucial to predict transpiration reductions under limited soil water conditions and for a rational scheduling of irrigation. In order to assess whatever water stress model, it is necessary to estimate critical thresholds of soil water status, below which plant transpiration starts to decrease. The main objective of the work is to identify the shape and to determine the parameters of table olive orchards (Olea europaea, var. Nocellara del Belice) water stress function, assessed according to relative transpiration or leaf/stem water potential. In order to assess different water stress functions describing the eco-physiological field r…
Climate Aridity and the Geographical Shift of Olive Trees in a Mediterranean Northern Region
2021
Climate change leverages landscape transformations and exerts variable pressure on natural environments and rural systems. Earlier studies outlined how Mediterranean Europe has become a global hotspot of climate warming and land use change. The present work assumes the olive tree, a typical Mediterranean crop, as a candidate bioclimatic indicator, delineating the latent impact of climate aridity on traditional cropping systems at the northern range of the biogeographical distribution of the olive tree. Since the olive tree follows a well-defined latitude gradient with a progressive decline in both frequency and density moving toward the north, we considered Italy as an appropriate case to i…
Olive Yield and Future Climate Forcings
2013
Abstract The rainfall reduction and the temperature increase forecasted for Mediterranean regions would likely increase the vegetation water stress and decrease productivity in rainfed agriculture. Olive trees, which have traditionally been grown under rainfed conditions, are one of the most characteristic tree crops from the Mediterranean not only for economical importance but also for minimizing erosion and desertification and for improving the carbon balance of these areas. In order to simulate how climatic change could alter soil moisture dynamics, biomass growth and fruit productivity, a water driven crop model is used in this study. The model quantitatively links olive yield to climat…
Genetic Structure of Wild and Cultivated Olives in the Central Mediterranean Basin
2006
Background and Aims: Olive cultivars and their wild relatives (oleasters) represent two botanical varieties of Olea europaea subsp. europaea (respectively europaea and sylvestris). Olive cultivars have undergone human selection and their area of diffusion overlaps that of oleasters. Populations of genuine wild olives seem restricted to isolated areas of Mediterranean forests, while most other wild-looking forms of olive may include feral forms that escaped cultivation. Methods: The genetic structure of wild and cultivated olive tree populations was evaluated by amplified fragment length polymorphism (AFLP) markers at a microscale level in one continental and two insular Italian regions. Key…
Olive agroforestry systems in Sicily: Cultivated typologies and secondary succession processes after abandonment
2011
The first part of this study provides an overview on Sicilian olive systems. Subsequently, the study describes the different typologies of cultivated agroforestry systems present in South-Eastern Sicily employing olive trees in association with other Mediterranean tree species, in particular for the production of firewood, coal and animal food (downy or pubescent oak, holm oak, cork oak), but also in association with forage or grazing species (oat, barley, vetch, etc.) or cereals. The study shows that Sicilian agroforestry systems are much more diversified than it was known so far. In the second part, the study describes the spontaneous colonization processes by plants, observed in abandone…
Growth and physiological responses of young olive trees affected by Olive leaf yellowing associated virus
2017
We studied the effect of Olive leaf yellowing associated virus (OLYaV) on biometric and physiological changes in olive. The trial was carried out on 32 two-yearold virus-free trees of 'Frantoio' grafted on virus-free olive seedlings and grown in 32-L pots. Half of the trees were inoculated with OLYaV in the fall of 2007. At 6, 18, and 24 months after inoculation, tree height, basal trunk diameter and total leaf number were determined, and leaf area tree-1 was estimated from a 50-leaf subsample. Twigs of various order were also counted and measured. At the end of the experiment, dry matter partitioning, leaf gas exchange and water potential were also measured. Total twig length and number, t…
Hydraulic kinetics of the graft union in different Olea europaea L. scion/rootstock combinations
2007
The hydraulic resistance of young olive trees grafted on rootstocks with contrasting size-controlling potential was measured 30, 90, 360 and 480 days after grafting. Olive (Olea europaea L.) clones inducing plant vigorous growth (Leccino ‘Minerva’, LM) or dwarfing (Leccino ‘Dwarf’, LD) were studied in different scion/rootstock combinations (LD/LD, LD/LM, LM/LD, LM/LM). Plants growing on LD root systems developed lower leaf surface areas (about 50% less) than plants grafted on LM rootstocks. Graft union represented the largest fraction (up to 85%) of whole-plant hydraulic resistance 30 days after grafting, and still represented an important fraction of it 2 months later (40–55%). Four-hundre…
Effect of soil permanent grass cover on growth, yield and water status of rainfed olive trees in Sicily
2017
The study was carried out in an olive grove located along the hills of northern Sicily where soil had been managed for decades by chemical weeding. Starting in 2008, one portion of the grove was left non-weeded, and the permanent grass cover was managed by mowing 2-3 times per year in winter and spring. In 2011, 2012 and 2013, yield, average drupe weight, percentage of drupe black color (veraison), trunk circumference, shoot elongation, and leaf relative water content (RWC) were determined on 34 adult trees of the cultivar 'Biancolilla' with uniform size and age. In 2013, soil organic matter content and leaf nutrient concentrations were also determined in the two portions of the grove. As e…
Diurnal Regulation of Leaf Water Status in High- and Low-Mannitol Olive Cultivars
2014
The role of mannitol and malic acid in the regulation of diurnal leaf water relations was investigated in ‘Biancolilla’ (high-mannitol) and ‘Cerasuola’ (low-mannitol) olive trees. Photosynthetic photon flux density (PPFD), vapor pressure deficit (VPD), stomatal conductance (gs), transpiration rate (T), relative water content (RWC), mannitol and malic acid were measured in ‘Biancolilla’ and ‘Cerasuola’ leaves during a dry and hot day of summer in Sicily. In general, leaves of ‘Biancolilla’ trees exhibited greater mannitol content, higher gs and T, but lower RWC than leaves of ‘Cerasuola’ trees. Differences in gs and T between the two cultivars were evident mainly in mid to late morning. ‘Bia…
Is rootstock-induced dwarfing in olive an effect of reduced plant hydraulic efficiency?
2006
We investigated the hydraulic architecture of young olive trees either self-rooted or grafted on rootstocks with contrasting size-controlling potential. Clones of Olea europea L. (Olive) cv ''Leccino'' inducing vigorous scion growth (Leccino ''Minerva'', LM) or scion dwarfing (Leccino ''Dwarf'', LD) were studied in different scion/rootstock combinations (LD, LM, LD/LD, LM/LM, LD/LM and LM/LD). Shoots growing on LD root systems developed about 50% less leaf surface area than shoots growing on LM root systems. Root systems accounted for 60-70% of plant hydraulic resistance (R), whereas hydraulic resistance of the graft union was negligible. Hydraulic conductance (K = 1/R) of LD root systems w…