جستجوی مقالات مرتبط با کلیدواژه « زیتون » در نشریات گروه « زیست شناسی »

This study was conducted to investigate the frost status in the 11 commercial cultivars, three newly introduced cultivars and two genotypes of olives. After the occurrence of frost at the Tarom region of Zanjan province in February 2019, three trees from each cultivar were selected. Frost symptoms were recorded based on observational indices. Gas exchange traits (stomatal conductance, transpiration and photosynthesis rate), proline content, pigments and leaf nutrients were measured. Evaluation of frost severity based on observational indices revealed that there was a large difference between cultivars to frost tolerance. Principal component analysis differentiated susceptible cultivars and genotypes to frost. Zard, Grossane, Abou-Satl, Konservolia, Picual and Cornicabra cultivars were grouped as frost tolerant cultivars. Direh, Meshkat, Amin and Koroneiki cultivars were introduced as completely cold sensitive. Among the many evaluated traits for screening olive cultivars and genotypes, proline content and pigment (SPAD index) were identified in discrimination as the most important distinguishing traits of olive cultivars in terms of cold tolerance.

Arbuscular mycorrhizal fungi are one of the most important mycorrhizal symbioses in plants that improve the inorganic nutrition and growth. These fungi act as biofertilizers, bioregulators and bioprotectors. In this research, in order to evaluate the effect of Glomus mosseae‌ and G. intraradices on rooting and growth of olive (Olea europaea L.) cuttings in two cultivars Koroneiki and Yellow, a factorial experiment in a completely randomized design (CRD) in two factors (olive cultivars and arbuscular mycorrhizal fungi species) and three replications was done. The results showed that mycorrhizal inoculation create root colonization and colonization severity (the amount of mycorrhizal fungus penetration in the root) in both cultivars. Interaction effect of cultivar and fungi species was significant on all measured traits. Cultivar G. mosseae was significantly superior compared to cultivar G. intraradices and non-inoculated treatment in enhancing all measured traits except for proportion of shoot dry weight to root. Also, the concentration and uptake of phosphorus, iron, potassium and magnesium in leaves and whole plant increased in mycorrhizal treatments. According to the obtained results, it is recommended to use G. mosseae for acceleration of the rooting of cutting and establishment in olive cultivars.

Cold tolerance is one of the important factors in the distribution of plant species. The aim of this study was to investigate the survival and gas exchange responses of olive (Olea europaea L.) seedlings to low temperature and freezing stress. For this purpose, 144 two-years-old potted seedlings of olive (cultivar yellow) with averaged height of 30 cm were examined as factorial in a completely random design (CRD) with 3 replications. Seedlings were exposed to six temperature levels (+2, -5, -7, -10, -16, and -20° C) for 1 and 3 hours. Gas exchange parameters such as net photosynthesis rate, transpiration, and stomatal conductance were measured for each treatment in three steps: before stress, immediately after stress, and 12 days after stress. Results showed that in each temperature level net photosynthesis rates, stomatal conductance, and transpiration reduced in both 1 and 3 hours chilling and this reduction was higher in seedlings subjected to 3 hours chilling. Olive seedlings exposed to -10, -16 and -20 °C temperatures were dead while in seedlings subjected to -7 °C and higher temperature (under both 1 and 3 hours chilling) gas exchange variables were recovered on day 12 after the stress. In general, this research revealed that olive seedlings (cultivar yellow) are able to tolerate low temperature up to -7°C for 3 hours.

In order to investigate the effect of different levels of of IBA and strains of Pseudomonas fluorescens bacteria, an experiment was conducted as factorial with completely randomized design containing two factors and three replications. In the first factor, effect of three levels of IBA (0, 2000 and 4000 mg/ ml) and in the second one effect of two strains of P. fluorescens (R5 and R64) on olive (Olea europaea cv. conservaliya) were investigated. Results showed that bacterial inoculation with R5 strains increased shoot and root dry weight, total dry weight, nitrogen concentration and phosphorus uptake compared to control, but there was no significant difference between R5 and R64 strains in terms of total chlorophyll. The 2000 mg/ml IBA also increased shoot and root dry weight, nitrogen concentration, total chlorophyll and total dry weight related to control, while the maximum phosphorus uptake was obtained in 4000 mg/ml IBA. The interaction effect of IBA and bacteria showed that in morphological characteristics and uptake and concentration of elements, maximum average were obtained in 2000 mg/ml IBA and R5 strain treatment. According to the obtained results, the application of both of 2000 mg/ml IBA and R5 strain for improvement of rooting is recommended.

Temperature is one of the most important factors limiting the production and distribution of olive. Different olive cultivars show diverse responses to low temperature and so, the selection of cold tolerant cultivars is the most effective method to avoid frost damages. The main purpose of this study was to compare freezing tolerance of seven olive cultivars and to investigate the relationship between freezing tolerance and maximum quantum yield of PSII, soluble carbohydrates, malondialdehyde, stomatal density, leaf tissue density and leaf relative water content during cold acclimation. After measuring the chlorophyll fluorescence, leaf samples from each cultivar were collected and were divided into two groups. The first group was subjected into different freezing temperatures (0, -5, -10, -15, -20 and -25 °C) for 12 h, in order to determine their freezing tolerance. The second group was used for some biochemical and physiological parameters analysis. The results showed that there was a significant difference among olive cultivars with respect to freezing tolerance. The highest freezing tolerance was related to ‘Amphisis’, ‘Shengeh’ and ‘Conservallia’ cultivars (LT50 -13.14, -11.72 and -11.20 °C, respectively) and the lowest tolerance to the ‘Rashid’ (LT50 - 6.90 °C). In freezing tolerant cultivars, Fv/Fm, soluble carbohydrates and leaf density were more than other cultivars, indicating a positive relationship with freezing tolerance. The concentration of malondialdehyde, stomatal density and relative leaf water content in freezing tolerance cultivars such as ‘Amphisis’, ‘Shengeh’ and ‘Conservallia’ were less than freezing sensitive cultivar of ‘Rashid’.

The synthesis of metal nanoparticles has attracted the attention of scientists in various fields, particularly in the chemical, physical, biological and medical sciences. Using extract of plant for nanoparticle synthesis can be advantageous over other biological processes because it eliminates the elaborate process of maintaining cell cultures and can also be suitably scaled up for large-scale nanoparticle synthesis. In this study, zinc oxide (ZnO) nanoparticles were successfully synthesized from ZnNO3 using Olive (Olea europaea).  Nanoparticles were characterized with the help of Transmission electron microscopy (TEM) and UV–Visibe absorption spectroscopy. To study the effects of zinc oxide (ZnO) nanoparticles (0, 200, 400 ppm) on growth, proline and Malondialdehyde (MDA), total phenol, flavonoid, Hydrogen peroxide (H2O2), chlorophylls and anthocyanin content in plant of Borago officinalis, experiment was carried out at shahid bahonar university of Kerman University in 2014. Synthesised ZnO nanoparticles were confirmed by the absorption maxima at the wavelength of 370 nm. TEM image revealed that ZnO nanoparticles were spherical with average size 41 nm. Results showed the plants that treated with zinc oxide (ZnO) nanoparticles, increased root and shoot length. But soluble suger, anthocyanin and CAT activity in the plants that treated with zinc oxide (ZnO) nanoparticles had no significant effect. On the other hand, Zinc oxide (ZnO) nanoparticles decreased proline and chlorophyll content. In addition, ZnO nanoparticles treatment at 400 ppm increased phenol content, H2O2, lipid peroxidation and APX, GPX, PAL activity. Reactive oxygen species generation was a toxicological mechanisms of nanoparticles that increased H2O2 content and lipid peroxidation in plants. ZnO nanoparticles causing increased production of reactive oxygen species and decreased proline and chlorophyll content in Borago officinalis.

Probiotics are defined as live microorganisms that when administered in adequate amounts, confer a health benefit on the host and they can prevent from or cure some diseases. Most probiotics are strains of Bifidobacterium or Lactobacillus species. The Lactobacillus genus consists of a genetically and physiologically diverse group of rod-shaped, Gram-positive, non-spore forming, non-pigmenetd, catalase negative and microaerophilic to strictly anaerobic. Olive green is one of the oldest plant which used as an important food and has a key role in health, prevention and control of digestive, blood, and heart disease. It may be a proper carier for transporting of probiotics. Therefore, this property of olive green evaluated. In this study, 16 olive sample (packed, unpacked, and crude) were prepared to isolation of Lactobacilli. After isolation of total bacteria, morphological, cultural, and biochemical tests were used to identification of lactobacillus species. Finally, 4 strain of Lactobacillus plantarum and 1 strain of Lactobacillus acidophilus were identified. Our results shows that, in addition to many food advantages, olive green can be a carrier of probiotics.

Olive is one of the moderately resistant plants to salinity and the amount of resistance depends on the cultivar. Therefore, this species can be used as a model to study the responses of wooden plants to salt stress. In this study, six-months-old plantlets of three olive cultivars, including Arbequina, Arbosana, and Koroneiki were under salt stress through various concentrations of sodium chloride, containing 0, 50, 100, and 200 mM for five months, and sprayed with proline at 0, 100, and 200 mg/L for three times. At the end of the stress period, the number of leaves on each plant was counted; and thickness, length and width, and fresh and dry weight of the leaves were measured. Carotenoid content of leaves was determined using DMSO, total leaf phenol was measured by Folinciocalteu reagent, and glucose levels were estimated based on McCready. The results indicated that the number of leaves was decreased by increasing salinity levels and Arbosana had the greatest reduction. Koroneiki showed a significant reduction in leaf length and width at 200 mM and application of proline could not prevent this decline. The lowest fresh and dry weight was observed at 200 mM salinity. Leaf thickness was increased in the response of salt stress and the content of carotenoids reduced. Among the cultivars studied, Arbosana had the lowest total phenolic contents. Also, at salinity 200 mM, the highest and the lowest sugar content was observed in Arbosana and koroneiki, respectively. Plantlets treated with proline 200 mg/L had the highest carbohydrates.

Fatty acids accumulation pattern and oil oxidizability during fruit ripening of two olive cultivars of high and low oleic acid, Shengeh and Mary,were studied respectively while the environmental conditions kept constant. Samplings were done at 90, 120, 150 and 180 days after flowering (DAF) and the fatty acid composition was determined by gas chromatography (GC) after seed oil extraction by n-hexane. Analysis of variance (ANOVA) showed that accumulation of stearic, oleic and linoleic acids were significantly influenced by genotype. Indeed, there was a significant correlation between time andboth oleic and linoleic acids. Overall measurements demonstrated higher palmitic and linoleic acids in Shengeh cv. and higher steraric and oleic acids in Mari cv. During four studied stages olive development . Also, there was a positive correlation between linoleate and calculated oxidizability value (COX). Increasing pattern of oleic acid content in both genotypes implies the inhibitory effect of oleic acid on the phospholipase activity of oleosins leading prevention in out-course germination It is worthy to note that genotype plays a crucial role in fatty acid content in development stages as seed oli acid content in mary cv. is higher then Shengeh.

Low quality of irrigation water along with increasing salinity level has reduced the olive yield over recent years in Iran. Screening of salinity tolerance in olive cultivars using gas-exchange parameters، water use efficiency، and relative leaf chlorophyll content are important in olive development programs. This study was carried out to assess the salinity tolerance of four olive cultivars (Amygdala، Dakal، Shiraz and Zard) under greenhouse condition. A factorial experiment through completely randomized design with four replications and four levels of salinity including 0، 100، 150، and 200 mM NaCl were used. The results showed that with increasing salinity levels CO2 assimilation rate، stomatal conductance، transpiration rate، water use efficiency، and relative chlorophyll content decreased and internal CO2 concentration increased. The results also indicated that there were significant differences among the examined olive cultivars. In overall، the results showed that “Zard” and “Shiraz’ cultivars were the most tolerant cultivars to salt stress.

Treatment with microorganisms is a new developing method that in this field, probiotic bacteria, especially lactic acid bacteria have a significant role. Olive is a productive and useful Iranian native plant which is rich in lactic acid bacteria. In this study, a number of Lactobacillus plantarum strains were isolated from Iranian native olives and some of their probiotic properties were investigated. At first, different strains of lactic acid bacteria were isolated from Iranian native olive on MRS agar medium, and after biochemical and molecular identification of bacteria, some probiotic properties such as acid and bile salt tolerance; and antimicrobial effects against two pathogenic species of Enterobacteriaceae, Escherichia coli (PTCC1399) and Shigella dysenteriae (PTCC1188) were studied by disk and well diffusion agar methods. According to error reduction, each test was performed in triplicate. Average zone of inhibition for each strain was compared by one-way ANOVA. According to biochemical tests, 57 percent of 28 isolated lactic acid bacteria were identified as Lactobacillus plantarum. Among these strains, 75 percent and 81.5 percent were acid and bile tolerance respectively. In the molecular analysis, 6 strains were shown specific bands in PCR reaction which performed by specific primers designed for Lactobacillus plantarum. The results described antimicrobial effects of Lactobacillus plantarum isolated from Iranian native olives on two enteric pathogens, Escherichia coli and Shigella dysenteriae. Discussion and According to probiotic properties of isolated Lactobacillus plantarum from Iranian native olives, using them is acceptable as an important and practical approach to prevent infectious disease and its treatment due to Escherichia coli and Shigella dysenteriae.

Aim and Olive tree (Olea europaea L.) has a high economic value and many countries such as Iran and Mediterranean countries use its oil and canned fruits. Conventional propagation programs are time consuming. Tissue culture technique allows producing high quality and rapid growing plants. The objective of the present study was to evaluate the effect of chelated iron and nano-chelated iron on the growth rate of in vitro microshoots. Uninodal explants of young shoots from a mature olive Oleaeuropaea L((cv. Dezful), were cultured in DKW medium supplemented with 2ip (4m〖g.L〗^(-1)). Sterile microshoots were subcultured in DKW medium supplemented with different concentrations of nano-Fe and Fe chelate (60, 120,180, 240 µM). Forty-five days after subculture, growth parameters were investigated. Results indicated that the growth parameters (number of nodes, microshoots, leaves and stem length) significantly decreased in the presence of nano Fe. The maximum level of leaves number and stem length was achieved in the high concentration of Fe (180 µM). Upon increasing the Fe or nano Fe content in the medium, the chlorophyll b and carotenoid levels were significantly increased. Fe chelate was more effective than nano Fe. Microshoots couldnt survive in the highest concentration of nano Fe and Fe (240 µM). The best results were obtained in the presence of Fe (120, 180 µM)

The olive tree (Olea europaea L.)، a representative drought – stress – tolerant plant، is one of the most typical and economically important plant species. As olive cultivars may exhibit different level of drought tolerance، the selection of the most drought – tolerant for cultivation in this area is important. For this purpose، the effect of water deprivation on plant water potential (ψw)، relative water content (RWC)، total soluble protein، proline، malonedialdehyde (MDA)، superoxide dismotase (SOD) and preoxidase enzyme activity in three olive cultivars (Olea europaea L. var ‘Dezfoli’، ‘T2’، ‘Koroneiki’) was studied. Olive trees، grown under field condition in Ahwaz were kept without irrigation for 14 days periods. Changes Of these parameters were measured on 1st، 4th،8th، 13th of the period. Plant water status (ψw)، relative water content (RWC) and total soluble protein of three cultivars decreased with increasing level of drought stress. Proline and MDA content increased with increasing level of drought stress. There was not any significant difference among three cultivars except MDA. Dezfoli showed lower value of MDA content. Significant increasing of SOD and POX activity was observed during the progressive increment of drought stress in all three cultivars. Dezfoli showed higher levels of SOD activity. We concluded higher levels of SOD activity and lower level of MDA in Dezfoli during the development of drought stress indicate this cultivar has more tolerance to oxidative stress due to drought stress than the other cultivars.

Olive (Olea europaea L.) is an evergreen tree، traditionally cultivated in the Mediterranean area. Olive tree cultivation is curtailed in cold areas because they can rarely tolerate temperatures at and below -12°C. In recent years، because of high demands for olive oil and its fruit، the cultivation of olive trees has been increased in Iran. To investigate the impact of cold stress on the content of total phenol، antioxidant activity and three major phenolic compounds including oleuropein، hydroxyl tyrosol and tyrosol and also phenylalanine ammonialyase (PAL) activity، one-year old olive cultivars of Sevillana and Frantoio were exposed to low temperatures of 10، 5، 0، -5، -10، -15، -20 and control 20°C for 12 h، gradually. The results indicated that total phenol content، antioxidant activity and PAL activity were increased under cold stress in both investigated cultivars. However، PAL activity in Sevillana showed significant decrease at and below -5°C while in Frantoio cultivar there was significant dwindling blew -10°C. Oleuropein content significantly increased during cold stress but، tyrosol and hydroxy tyrosol content decreased in both cultivars compared with the controls. According to the current results، Frantoio and Sevillana showed different resistance under cold stress، so that Frantoio was more resistant than Sevillana.

In this study، for immunological analysis of the expression of the P5CS (Delta- 1- pyrrolin-5- carboxylate synthetase) gene in osmotic stress condition، embryos of the olive plant cv. Zard were cultured on the solid ½ MS media، after than 4 weeks، half of the plantlets were transferred to the solid ½ MS containing 200 mM NaCl and they were sub- cultured about 2 weeks، then total protein was extracted from fresh leaves of both plantlets under stress and non stress conditions and was measured the content of protein by brad ford test. Then they were compared by SDS-PAGE gel electrophoresis. To probe the effect of p5CS over expression on salinity stress tolerance، poly clonal antibody developed in rabbit against P5CS protein was used. The result of immunological methods for specific detection of P5CS gene، strongly indicated P5CS up – regulation in stressed plantlets versus non stressed plantlets.

Olive (Olea europaea L.) is an evergreen tree traditionally cultivated in the Mediterranean area, resistant to some degree to salinity and drought conditions. However, olive trees are not so resistant to low temperatures. In recent years, because of high demands for olive oil and fruit, the cultivation of olive trees has been increased in Iran. Different cultivars of olives have diverse reactions to cold stress and so, the selection of cold resistant cultivars is the most effective method to avoid frost damages. In order to compare the impact of cold stress on the content of total protein, lipid peroxidation and photosynthetic pigments, 1-years old olive cultivars of Sevillana and Frantoio, were exposed to low temperatures of 10, 5, 0, -5, -10, -15, -20 and control 20 °C for 12 h. The results indicated that the both examined cultivars were resistant to 0 °C temperature with no significant damages. The photosynthetic pigments of Frantoio did not change even in -15 °C and malondialdehyde levels slightly increased compared with the control (20 °C). Total protein content in Frantoio showed significant decrease from -10 °C, while in Sevillana cultivar there was significant decline of total protein content from -5 °C. Therefore, it can be concluded that Frantoio is more resistant to cold stress than Sevillana.

Germplasm banks are basic sources for selecting and breeding programs. Iran is known as one of the origins of olive in the world with many different olive cultivars and considerable number of old olive orchards. Evaluation and classification of existing olive genotypes in Iran seems to be very important. Thirty-five years ago, 25 olive genotypes (originated from different parts of the world) had been transferred to an olive orchard near Gorgan city. In 1377 their duplicated plants obtained from these genotypes were transferred to collection of Olive Research Station in Tarom-Zanjan. Each selected genotypes propagated with nine replications and nominated as “Tn”. In this study we used morphological characteristics to identify these unknown genotypes. Samples were collected from 15 genotypes with three replications. Morphological data used for cluster analysis. By using of variance analysis, all the studied quantitative characters (except one) revealed significant differences between genotypes and clearly separated from each other. Comprising results with typical known Iranian olive cultivars, showed a remarkable distance between them.