جستجوی مقالات مرتبط با کلیدواژه "olive" در نشریات گروه "بیوتکنولوژی و ژنتیک گیاهی"

Olive (Olea europaeaL.) is an evergreen plant which belongs to Oleaceae family. In an attempt to investigate the impact of pollination and branch direction as well as the interaction effect of these two treatments on the quality and quantity of fruit in two varieties of yellow and Mary olive in the region of Fars, an experiment was carried out during 2005-2006. The experiment was conducted with three treatments of pollination (i.e. self-pollination, open pollination, and wind pollination without the interference of pollinating insects) in four replications following a randomized complete block design by means of net in four main geographical directions of yellow and Mary olive trees. The results indicated that in comparison to self-pollination, open pollination significantly increased the yield level at P<0.01 in the two cultivars. Self pollination resulted in an increase in the number of parthenogenetic and unnatural fruits which reduced the yield and quality of these fruits in comparison to the open treatment. The variance analysis of yields demonstrated genetic differences between cultivars as an indication of production power. The comparison of open pollination treatment and wind pollination without the interference of pollinating insects was not significant. The highest and the lowest percentages of full flowering were respectively observed in the southern and northern directions. An increase in full flowering in the southern part resulted in an increase in the amount of initial fruit. However, after the primary and secondary flower loss, no significant difference was observed in the final fruit formation.

Olive is medicinal which is nowadays grown as an ornamental plant in cities. Given the tendency of people to use herbs, it appears essential to explore whether the plants grown in cities have the same properties as the naturally grown plants or some of their traits are changed due to the pollution of the air in the cities. The antimicrobial effect of olive leaf extracts on the activity of two gram-positive (i.e. Bacillus subtilis and Staphylococcus areous) and gram-negative bacterium (i.e. Pseudomonas aeroginosa and Escherichia coli) was explored under laboratory condition. Olive Olea europaea leaves were collected from a clean (district 22) and polluted (district 6 and 7) areas. Different aqueous, ethanol, and methanol concentrations (10, 20, and 50%) were prepared. To compare the antimicrobial effects of extracts, broad-spectrum antibiotics ciprofloxacin disks (CP) and Ceftizoxime (CT) were used. The analyses indicated that there was a significant difference in the activity of olive leave in clean and polluted areas and different methods of extraction. The highest amount of antimicrobial properties was observed in ethanol extracts. These extracts had antibacterial effect on Escherichia coli, Pseudomonas aeroginosa, and Bacillus subtilis, in clean area. Thereby, people should be informed that the olives planted in the polluted regions of Tehran (street, park, or houses) are merely ornamental and do not have medicinal value.

Verticillium wilt is one of the most important vascular diseases of olive. For this reason, investigating different aspects of this disease such as distribution, biology, pathogenicity, and disease management have always been considered significant. In an attempt to investigate host-pathogen interaction, the present experiment was carried out to study the histopathology of olive (cultivar Zard) inoculated by Verticillium dahliae. Root-dipping method for 30 minutes was used for the inoculation of the seedlings by spore suspension with concentration 109 spore/ml. Four to twelve weeks after inoculation, with the occurrence of wilt symptoms, transversal sections were prepared from various parts of the stem and root. Then, very thin transversal sections were prepared and after different stages of staining, microscopic slides were prepared. The results of the microscopic investigations indicated that the causal agent of Verticillium wilt has caused disorders in the physiology through spreading into vessels, obstruction of xylem vessels, and their destruction. The casual agent also resulted in disorder in the flowing of vascular sap and caused shoot wilt. The results indicated that the seedlings obstructed the vessels and prevented the spread of pathogen with producing tylose. The pathogenicity and defensive mechanisms associated with host-pathogen interaction and their roles in susceptibility rate of the olive to Verticillium wilt have been discussed in this research.

The agronomic types of the Iranian olives, which are distributed under a similar name, have different varieties. The molecular diversity of 46 olive tree samples of 10 cultivars (derived from two main olive cultivars, i.e. Rowghani and Gelooleh) was investigated in the initial phase of the present study using Random Amplified Polymorphic DNA (RAPD) analysis with 20 markers. The study was carried out at the National Research Center for Genetic Engineering and Biotechnology (NRCGEB). 53.1% of the marker were polymorphic. The obtained results were analyzed using NTSYS and SPSS software. During the second phase of the study, identical samples were omitted and the analysis was repeated using 20 RAPD markers. From among the 20 markers, 18 (79.5%) were polymorphic. Different techniques were applied for measuring the similarity matrix and cluster analysis. The best cluster was obtained from Dice similarity matrix and the UPGMA procedure. The average similarity coefficient obtained from Dice similarity materix indicated that the cultivars were not that much diverse. Analyzing the main characteristics of the olive cultivars differentiated them appropriately. The results of the cluster analysis confirmed the outcome of the morphologic analysis to a great extent. Generally speaking, conducting a molecular experiment along with the morpholic categorization appears essential. The RAPD markers were appropriately applied for the morphological analysis during the initial phase of the study. The obtained results can be further confirmed and analyzed using other markers.

The experiments on Olive plants (Olea europaea L varManzanillo) were done for 4 months and the effect of different formd of Nitrogen (NO3- NH4 and urea) was carried out on factorial on the base of complete randomized blocks design with three replications in greenhouse conditions. Different nitrogen form was applied at 3 levels (4, 8 and 16 mM). Nitrogen is the mineral nutrient most commonly applied in olive.. The results indicated that the treatment of NH4 (8mM) have the greatest effect on the amount of increase weight per plant and treatment of NH4 (16 mM) have the greatest effect on the increase weight stem, leaf and root. No difference in root N concentration was observed between three N forms. there is no signification difference of weight roots the effects of N forms applied of olive plants.

Verticillium wilt is one of the most important vascular diseases of olive. It has always being considered to survey its various aspects such as distribution, biology, pathogenicity and management. In order to investigate host-pathogen interaction, this research was carried out to study histopathology of olive (cultivar Zard) inoculated by Verticillium dahliae. Rootdipping method for 30 min was used for inoculation of the seedlings by spore suspension with concentration 109 spore/ml. 4-12 weeks after inoculation, with occurrence of wilt symptoms; transversal sections were prepared from various parts of the stem and root. Then, very thin transversal sections were prepared and after different stages of staining, microscopic slides were prepared. The results of microscopic investigations showed that the causal agent of Verticillium wilt has caused disorders in physiology and flowing of vascular sap through spreading into vessels, obstruction of xylem vessels and their destruction. The results also showed that seedlings with producing tylose caused obstruction of vessels and prevented spreading of pathogen. Pathogenicity and defensive mechanisms associated with host-pathogen interaction and their roles at susceptibility rate of olive to Verticillium wilt had been discussed in this research.