Olive Trees (olive + tree)

Distribution by Scientific Domains


Selected Abstracts


Relationships between the olive fly and bacteria

JOURNAL OF APPLIED ENTOMOLOGY, Issue 9-10 2008
P. Sacchetti
Abstract The relationship between the olive fly population and epiphytic bacteria of the olive tree was investigated by carrying out a 1-year survey in the field. The olive fly population affected the number of bacteria present on the olive surface. Scanning electron microscope observations demonstrated that bacteria may be ingested by the fly's mouth apparatus through the midline of the pseudotracheae. DNA amplification of the oesophageal bulb content using 16S bacteria universal primers and DNA sequencing evidenced that Candidatus Erwinia dacicola was the predominant species present. The role of bacteria in olive fly biology is discussed. [source]


Retention and Distribution of Polyphenols after Pan-Frying of French Fries in Oils Enriched with Olive Leaf Extract

JOURNAL OF FOOD SCIENCE, Issue 8 2007
A. Chiou
ABSTRACT:,Palm oil, olive oil, and sunflower oil were supplemented with an extract rich in polyphenols obtained from olive tree (Olea europaea) leaves at levels of 120 and 240 mg total polyphenols per kilogram of oil. Pan-frying of potatoes was performed in both the enriched and the nonsupplemented oils under domestic frying conditions. Total polyphenol content was estimated by the Folin,Ciocalteau assay, oleuropein was determined by HPLC analysis, while other individual polyphenols by GC/MS analysis. Fourteen polyphenol species were identified in the olive leaf extract, among which oleuropein predominated (1.25 g/kg olive leaves). All the enriched oils contained oleuropein before and after frying. Oleuropein as well as other polyphenol species were detected in all French fries cooked in enriched oils. Polyphenol intake by consuming French fries pan-fried in the enriched oils was calculated to be 6 to 31 times higher than that in the case of French fries fried in commercial oils, being dependent on the frying oil type. [source]


Pho d 2, a major allergen from date palm pollen, is a profilin: cloning, sequencing, and immunoglobulin E cross-reactivity with other profilins

CLINICAL & EXPERIMENTAL ALLERGY, Issue 3 2005
J. A. Asturias
Summary Background Up to now, some date palm pollen (DPP) allergens have been described but very few data are available about their molecular nature. The aim of this study was to identify and characterize Pho d 2, a major allergen from this pollen. Methods Sera from 25 patients allergic to DPP were analysed by immunoblotting. Purification of DPP profilin was performed by poly- l -proline affinity chromatography. Profilin-encoding cDNA from DPP was cloned by using a RT-PCR strategy and recombinant allergen was expressed as a non-fusion protein in Escherichia coli. Natural and recombinant Pho d 2 were investigated by means of enzyme allergosorbent test to compare the immunologic properties of both allergens and to analyse cross-reactivity with other profilins. Results A 14.4 kDa protein was identified as a major allergen in DPP extract. Purification, cloning, heterologous expression, and inhibition experiments identified it as profilin (Pho d 2). Pho d 2 comprises 131 amino acids and has high sequence identity with other allergenic food and pollen profilins. The prevalence of specific IgE antibody reactivity to natural Pho d 2 by ELISA was 56% and 64% by skin prick test (SPT). Pho d 2 is an important allergen as it is responsible for more than 70% of the IgE reactivity to the pollen extract. IgE directed against Pho d 2 showed a strong cross-reactivity with other profilins such as those from olive tree and grass pollens. Conclusion Pho d 2, a 14.4 kDa protein identified as profilin, is a major and relevant allergen in DPP, as confirmed by SPT and thereby may elicit clinical symptoms in sensitized patients. [source]


Captures of the olive fruit fly Bactrocera oleae on spheres of different colours

ENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 2 2001
Byron I. Katsoyannos
Abstract Alighting and capture of wild olive fruit flies, Bactrocera oleae (Rossi) (Diptera, Tephritidae), on spheres of seven different colours was studied on Chios island, Greece. The 70-mm-diam plastic spheres, coated with adhesive, were suspended on olive trees. Yellow and orange spheres trapped the greatest number of males while red and black spheres trapped the greatest number of females. White and blue spheres were the least effective for both sexes. Peak captures occurred in the late afternoon and especially around sunset. Since mating takes place in the last hours of the photophase, the increased captures during that period may be related to the sexual behaviour of the fly. When red spheres were assessed against glass McPhail traps baited with 2% ammonium sulphate, which consist a standard tool for monitoring the olive fruit fly in Greece, there were no significant differences in male captures. However, spheres trapped almost three times as many females as McPhail traps. The possible mechanisms underlying colour discrimination, the motivation of alighting flies and the possible use of red spheres for monitoring and controlling B. oleae are discussed. [source]


First report of cottony-cushion scale (Icerya purchasi) on red berried mistletoe (Viscum cruciatum)

ENTOMOLOGICAL RESEARCH, Issue 1 2009
Diego RUBIALES
Abstract Cottony-cushion scale (Icerya purchasi) infestation on red berried mistletoe (Viscum cruciatum) is reported for the first time. Mistletoe is a hemiparasitic plant that was parasitizing stems of olive trees; however, I. purchasi infested only the mistletoe and not the olive. Economic implications are discussed. [source]


Effect of location on virgin olive oils of the two main Tunisian olive cultivars

EUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 9 2009
Mokhtar Guerfel
Abstract The olive oil content in phenolic compounds depends on the variety of the fruit used for its extraction as well as on the predominant climate conditions in the tree cultivation area. Here, we report on the characterization of virgin olive oil samples obtained from fruits of the main Tunisian olive cultivars Chemlali and Chétoui, grown in three different Tunisian locations, Zaghouan (North), Sousse (Center) and Sfax (South). Chétoui olive oil samples obtained from fruits of olive trees cultivated in Zaghouan and Chemlali olive oil samples obtained from fruits of olive trees cultivated in Sousse were found to have a higher mean total phenol content (1004 and 330,mg/kg, respectively). Olive oil samples obtained from fruits of both cultivars had different phenolic profiles and a higher content in 3,4-DHPEA-EDA when the olive trees were cultivated in Zaghouan. Both olive cultivars were found to have different responses to environmental conditions. Chétoui olive oil showed decreased oxidative stability when the fruits were obtained from olive trees cultivated in the center of Tunisia (34.8,h) and in Sfax (16.17,h). Furthermore, statistical data showed that the phenolic composition and oxidative stability of Chétoui olive oil varied more by location than those of Chemlali olive oils. [source]


GEOMETRICAL, THERMAL AND MECHANICAL PROPERTIES OF OLIVE FRUITS

JOURNAL OF FOOD PROCESS ENGINEERING, Issue 2 2010
MOHAMAD I. AL-WIDYAN
ABSTRACT In Mediterranean countries, olive trees play a significant economical role. Knowledge of olive fruits properties is essential for the efficient handling of the product and optimizing oil yield. The lack of such knowledge at the local level triggered this study in an attempt to report the fruit's chemical composition and some major engineering properties. Established procedures were followed in conducting the measurements and calculations on fruit samples. The study examined four major varieties of olive fruits, including Spanish, Black Spanish, improved Nabali and Nabali Baladi for their chemical composition and other properties, including geometrical, thermal and frictional properties. Thermal properties, including thermal conductivity, heat capacity and thermal diffusivity, ranged from 0.41 to 0.47 W/(m·K), 2.35 to 2.39 kJ/(kg·K) and 2.88 × 10,7to 2.779 × 10,7 m2/s, respectively. The geometrical properties of the Spanish and Black Spanish were quite similar except for roundness and sphericity. Similar results were found for improved Nabali and Nabali Baladi. The properties of weight, density and packing coefficient ranged from 2.22 to 8.60 g, 890 to 1,230 kg/m3 and 0.43 to 0.52, respectively. The fruit's static friction coefficient over mild steel, aluminum and softwood surfaces ranged from 0.20 to 0.30, 0.21 to 0.29 and 0.22 to 0.33, respectively. PRACTICAL APPLICATIONS In Jordan and other Mediterranean countries, olive fruits are produced in large quantities every season. They are very widely used as pickled fruits or are processed in mills to extract their oil. Despite the fact that fruit properties are a necessary prerequisite for the efficient handling and processing of fruits, literature search indicated the lack of a comprehensive study of scientific merit that reports on the engineering properties of olive fruits. In addition, it is established that knowledge of the fruit properties leads to optimized handling and processing and results in knowledge-based development of all processes and equipment that deal with the fruits. The practical merit of this study stems from the fact that it reports on the key properties of a major product (olive fruits) that has social, cultural and economical significance throughout a whole region and is expanding throughout the globe. [source]


Vegetative Compatibility and Pathogenicity of Verticillium dahliae Kleb.

JOURNAL OF PHYTOPATHOLOGY, Issue 7-8 2003
Isolates from Olive in Israel
Abstract Fifty-two isolates of Verticillium dahliae from olive trees grown at different locations in Israel were assigned to vegetative compatibility groups (VCGs), using nitrate non-utilizing (Nit) mutants. A higher frequency of nit1/nit3 mutants (95%) was obtained compared with NitM (5%), with 81% of the isolates being assigned to VCG4B and 19% to VCG2A. The pathogenicity of 14 randomly selected isolates (seven of each VCG) was tested on olive twigs (cv. Picual) and tomato. VCG4B and VCG2A isolates were similarly aggressive on olive. However, VCG2A isolates were more aggressive on tomato (line 139) than the VCG4B isolates as indicated by a higher colonization index. [source]


Analysis of pesticide residues by online reversed-phase liquid chromatography,gas chromatography in the oil from olives grown in an experimental plot.

JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 12 2006
Part II
Abstract The effect of the pesticide dose used to control pests in olive trees and the date of treatment on the residues present in the oil were studied for four organophosphorus pesticides (diazinon, malathion, trichlorphon and chlorfenvinphos) and one organochlorine (endosulfan). Pesticide residue analysis was performed using online reversed-phase liquid chromatography,gas chromatography, using an automated through oven transfer adsorption desorption interface and selective detectors, such as nitrogen,phosphorus detector and electronic capture detector. A simple filtration step was necessary before the chromatographic analysis of samples. The obtained data were statistically analyzed and conclusions about olive pesticide treatments are presented. Copyright © 2006 Society of Chemical Industry [source]


Olive oil production on bronze age Crete: nutritional properties, processing methods and storage life of Minoan olive oil

OXFORD JOURNAL OF ARCHAEOLOGY, Issue 1 2002
F.R. Riley
Archaeological studies on olive oil produced in Crete in the Bronze Age focus primarily on aspects such as the period when olive cultivation became widespread, the number of olive trees cultivated, or the quantity of oil stored in the Minoan palaces. Olive oil is however an organic substance, a perishable product, the nutritional and storage properties of which are determined by environmental, agronomic, processing and storage conditions. In this paper archaeological, environmental and biochemical evidence is combined to present a comprehensive picture of the potential quality, nutritional and storage properties of Minoan olive oil. The comparative evidence presented suggests that Minoan olive oil was equal in quality to the cold-pressed virgin olive oils produced today, and as such, the oil was nutritionally important in the Bronze Age and a valuable trade commodity. [source]


Effect of the combined treatment of insecticides and an attractant for the control of Phloeotribus scarabaeoides, a pest of Olea europea

PEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 3 2003
Estefanía Rodríguez
Abstract Different insecticides have been tested for the control of the olive bark beetle, Phloeotribus scarabaeoides Bern. This scolytid can be managed at two points in its biological cycle: in pruned logs, where it excavates reproduction galleries, or in living trees, after emergence from the logs, where it digs feeding galleries. In mortality laboratory bioassays, the efficiency of organophosphorus insecticides has been ranked as follows: chlorpyrifos,+,dimethoate,<,formothion,<,methidathion. Formothion and methidathion, the two most efficient, were sprayed on olive logs together with a pyrethroid insecticide, deltamethrin, and a formulation which combined an organophosphorus (fenitrothion) and a pyrethroid (cypermethrin) insecticide. Deltamethrin inhibited the excavation of new reproduction galleries and induced a repellent effect on the olive pest. In contrast, none of the organophosphorus insecticides or the combination, fenitrothion,+,cypermethrin, were able to control the olive bark beetle. In olive trees, deltamethrin controlled this olive pest without showing the repellent effect observed for logs. Ethylene, a plant hormone, has been reported as an attractant for the olive bark beetle. The use of dispensers which released ethylene increased the number of P scarabaeoides approaching the treated olive trees, thus favouring its use in a lure-and-trap control system. © 2003 Society of Chemical Industry [source]


First report of Phytophthora palmivora on olive trees in Argentina

PLANT PATHOLOGY, Issue 4 2007
G. Lucero
No abstract is available for this article. [source]