جستجوی مقالات مرتبط با کلیدواژه « olive » در نشریات گروه « آب و خاک »

As it has been for several years, drought conditions in various regions of Iran, including the central part of Marvdasht city in Fars province, have been very noticeable and have led to a severe decrease in the quantity and quality of groundwater, resulting in severe restrictions on agricultural production. Therefore, the farmers in the region have spontaneously turned to planting drought-resistant trees such as olives and pistachios. On the other hand, due to the significant reduction in the quantity and quality of groundwater in the study area, the quantitative and qualitative parameters of the fruit of the region's agricultural products, especially olive trees, which are irrigated under these conditions, are effective. It can be said that the quality parameters of olives increase with low irrigation and high salinity (to a tolerable extent). On the other hand, water and salinity stresses will have different effects on the performance of the mentioned plants. In this region, olives are used in two forms, canned and oil production. The amount of olive oil is often dependent on the growing conditions and fruit ripeness, and how the oil accumulates. The amount of oil in the dry matter of the fruit during the fruit ripening period (second fruit growth period) and its accumulation increases until the onset of dark purple. The quantity and quality of irrigation water affect the time and amount of oil accumulation, as well as the quality of olive oil. Also, the shelf life of olives in canned conditions and the shelf life of the aroma and taste of extra virgin olive oil are important features that will be controlled and examined by studying the density of olives during the fruit growth period. Therefore, the main purpose of this study is to investigate the changes in the density of olives during the fruit growth period under conditions of low irrigation and salinity stress.

The study area is located in the central part of Marvdasht city in Fars province, Iran, at geographical coordinates '693196;3303288' with an elevation of 1620 meters above sea level. According to the De Martonne method, the climate of the region is semi-arid and the dominant wind direction is eastern. Two years (2020-2021) of field experiments were conducted to study olive fruit density in a 20-year-old olive orchard (Roghani variety). The experiment utilized a factorial layout in a randomized complete blocks design with three replications. Five irrigation levels (I1-I5) were tested, ranging from 25% to 125% of olive water requirement. Three saline water levels (S1-S3) were also included, with S1 being saline well water with an electrical conductivity of 3.5-7.5 dS/m, S2 being a combination of 50% well water and fresh water, and S3 being fresh water. The weight and volume characteristics of olive fruits were examined and measured at seven different periods, starting from the fruit's appearance in June until its harvest in December for oil production. The I5S3 represented the control treatment.

Despite the fact that poor quality and quantity of irrigation water (S1, I1, and I2) will result in a decrease in the weight and volume of olive fruit, it is beneficial for improving the quality of suitable oil and will have an impact on the density of olive fruit. Oil production in olive fruit, which occurs during the second period of fruit growth, has a significant role in the density of the fruit. If the volume of fruit does not change (in the case of low-quality and low-quantity irrigation water), due to the increase in oil in a specific volume, it will lead to an increase in fruit weight and consequently an increase in olive density. The increase in density during the first growth period is accompanied by the production of dry matter in the fruit. A decreasing trend in the density of olive fruit can be observed in all irrigation treatments and different salinity levels in both consecutive years. The study found that normal irrigation water (I4 and I5) and appropriate quality (S2 and S3) increase the weight and volume of olive fruit and alter the density of olive fruit. The interaction effect of salinity and irrigation on the density of olive fruit was significant (5%) in both years. In 2020, changes in fruit density during the second period of fruit growth at salinity level (S1) were more pronounced in different irrigation treatments from I2 to I5 compared to other salinity levels (S2 and S3). The highest and lowest density values in 2020 were I2 and I3, respectively. The highest fruit density (1.1356 gr/cm3) was observed in the high salinity level (S1) and low irrigation treatment (I2). In 2021, the highest fruit density (1.1105 gr/cm3) in the first period of growth is related to S1, and in the second period of growth, it decreases compared to S2 and S3. In the same year, I1S3 had the highest value (1.0753 gr/cm3) and I5S3 had the lowest value (0.9899 gr/cm3) in the second stage of olive fruit growth. Although low quality and quantity of irrigation water (S1, I1 and I2) reduces the weight and volume of olive fruit, it is suitable for improving the quality of oil and will affect the density of olive fruit.

Field study of factors affecting crop water productivity is one of the most important strategies to achieve sustainable agriculture. In this study, the effect of water resources utilization methods on physical and economic indicators of water use efficiency was investigated. To achieve this goal, 30 olive groves including 16 groves under personal ownership and 14 groves under collective ownership wells were selected in Tarom located in Zanjan province. In order to calculate the water use efficiency indicators, irrigation parameters such as water consumption volume, irrigation schedule, crop yield, as well as production costs and sales revenue were determined. The average of water consumption in groves under the personal and collective ownership wells were obtained at 9800 and 12680 m3/ha, respectively. The average of CPD, BPD and NBPD indices in groves under the personal ownership wells were calculated 0.4 kg/m3, 46.9 and 24.4 thousand Rials/m3 and in groves under the collective ownership wells were 0.3 kg/m3, 36.4 and 15.2 thousand Rials/m3. The results of the independent T-test showed that there is no significant difference between the mentioned indicators in the two types of exploitation methods. Lack of control and supervision on water resources utilization, low knowledge of farmers in irrigation management and the incompatibility of water allowance with the crop water requirement, especially in groves with collective ownership wells were recognized as the most significant reasons for reducing the water use efficiency in some olive groves of study region.

Pseudomonas bacteria are the most important plant growth promoting rhizobacteria due to their widespread distribution in soil, their potential to colonizemany plant roots and possessing different plant growth promoting characteristics. The present study aimed to identify isolates of Pseudomonas fluorescens strains of olive tree rhizosphere in saline gardens of Qazvin province.  Plant growth promoting characteristics of  fifteen isolates of Pseudomonas fluorescens strains such as siderophore, auxin, hydrogen cyanide, ACC deaminase enzyme production, phosphorus solubility in liquid medium, pH changes and salt tolerance (NaCl, MgCl2 and CaCl2) (100, 200, 400 mM) were evaluated . Results showed that the dominant strains in producing ACC deaminase were Q7 and Q9, respectively. The Q2 strain was the best one to enhance the production of auxin (11.96 µg.ml-1). The solubility of phosphorus in conjunction with pH showed a negative correlation and the highest amount of dissolved phosphorus was related to Q13 (251) isolate. Also, the half of strains (40%) was not able to produce HCN. Commonly, all studied strains were able to produce siderophore after two, four and six days of incubation. Expect Q1 and Q8, other strains were able to grow in the considered salt concentrations. Based on the results, we concluded that some of these strains can be targeted for genomics studies to improve salt stress resistance in plants and orchards under saline soils conditions.

Although thousands of years ago olive was planted in the Mediterranean region, but there is little information about water consumption, crop coefficient and irrigation scheduling of olive trees. With existence limitation of water resources, the need for optimal water use in the agricultural sector is essential. Accordingly, the production of agricultural crops with a minimum water consumption is very important and considered as an important strategy for our country. Increasing demand for olive, either fresh or canned, or in the oil-milling industry, has led the country's agricultural authorities and gardeners to move towards a higher quality and quantity product, but it seems that achieving this goal without proper management in increasingly irrigated olive orchards is not possible. The olive is a resistant tree that produce acceptable yield even under restricted water conditions. Olive needs about 600 to 800 mm of annual precipitation to completely compensate the need for water. In this paper, a review of applied research on irrigation management of olive trees such as water requirement, crop coefficient, irrigation scheduling and its appropriate irrigation systems have been reviewed.

Responses of olive self-rooted cuttings of Zard cultivar (Olea europaea L. cv. Zard) to different levels of soil compaction and irrigation water salinity at the field capacity under greenhouse condition were studied. A loamy sand soil passed through a 4.76mm sieve, was poured into the PVC cylinders with diameter of 15cm and then they were compacted to be achieved the desired compaction levels. One-year-old rooted olive cuttings were transplanted into the PVC cylinders. After stabilization of cuttings, cylinders were irrigated by waters having different electrical conductivities at three days intervals, for five months. Some morphological and physiological properties of the olive plants were measured. As the salinity levels of irrigation water increased transpiration, stomatal conductance, photosynthetic rate, relative water content, water potential of stem, temperature difference between leaf and the environment and chlorophyll index decreased, for preserving plant internal water balance. Instantaneous WUE, electrolyte leakage and Na concentration of leaves increased as the salinity levels of irrigation water increased because of the decrease in transpiration and due to the plant’s salinity tolerance mechanisms. The relative water content of leaf, water potential of stem and temperature difference between leaf and environment decreased as the soil compaction increased due to decrease in water uptake. Photosynthetic indices of olive cuttings of Zard cultivar significantly decreased beyond the EC of 8 dS m-1.

In this study, five infiltration models including Kostiakov, Kostiakov-Lewis, Philip, Soil Conservation Service (SCS) and Horton were fitted to the experimental data using the double rings, and the empirical coefficients of these models were determined. Infiltration experiments were conducted in the gravelly sandy loam soil under and between the olive and orange trees in Fasa city, Fars Province, Iran. The results showed that all five models were fitted accurately to the measured data. The accumulated infiltration under the trees was higher than those measured between two trees. Higher infiltration under the tree canopies was probably due to the higher soil organic matter, the lower soil bulk density, and the tree root channeling, which were more pronounced when compared to the small pores in these soils. Despite the positive effect of sand particles on soil infiltration, the big gravel occurrence in soil would decrease the cross section area of water flow path, thereby reducing the infiltration. Therefore, changing the land use and planting olive and orange trees in the gravel soils would increase the infiltration rate and consequently, decrease runoff and erosion rates in such soils.

Responses of Olive self-rooted cuttings to irrigation water salinity and soil compaction in moisture of 0.9 saturation were studied. A loamy sand soil passed through a 4.75mm sieve, poured into PVC cylinders and compacted to achieve the desired compaction levels (bulk density of 1.3, 1.5 and 1.7 g cm-3). Then rooted olive cuttings were transplanted into the cylinders and were irrigated by waters with different salinities of 2, 5, 8 and 12 dS m-1 for five months. Instantaneous water use efficiency, electrolyte leakage, SPAD index and number of leaves to salinity of 8, and parameters of photosynthesis, stomatal conductance, transpiration rate, temperature difference between leaf and environment to salinity of 5 dS m-1 had no statistically meaningfull differences. Soil hypoxia decreases salinity tolerance mechanisms. With respect to olive plant growth, the bulk density of 1.3 g cm-3 was determined the optimum level of soil compaction for a loamy sand soil.

In horticultural plants¡ determining of evapotranspiration because of The existing problems in the direct measurement such as installing large lysimeter or the exact equipment and length during tree growth¡ often estimated indirectly and on the basis of meteorological data. With regard to the spatial variability of meteorological parameters and sometimes inappropriate distribution of meteorological stations estimating evapotranspiration is not possible with sufficient accuracy. Therefore use of procedures such as the remote sensing methods that consider these changes is best. In this study¡ evapotranspiration of olive trees were measured and determined with direct and indirect methods in two growing seasons 1393 and 1394 in Tarom district of Zanjan at different development stages. The actual evapotranspiration were determined by direct method¡ By measuring the moisture balance components and in the indirect method with help from the satellite imagery of landsat 8. Then by determining of the reference crop evapotranspiration¡ olive crop coefficient were calculated and were compared and evaluated. The results showed that calculated evapotranspiration and plant coeffiecient of remote sensing mehod in various olive growth stages matched with moisture balance data. So that¡ evapotranspiration correlation coefficient was 0.73¡ 0.87 and 0.82 for first¡ second and cumultative year¡ respectively. Moreover¡ correlation coefficients of plant coefficient was 0.95¡ 0.62 and 0.86¡ respectively. It is concluded that remote sensing method can be useful to estimate evapotranspiration of olive tree.

Salinity is one of the most important limiting factors for crops, because of most agronomic and horticultural crops are sensitive to salinity. On the other hands, considerable lands of the world were affected by salinity and they are increasing day by day. An experiment was conducted with five levels of irrigation water salinity in soilless culture and greenhouse condition to evaluate the effects of salinity on growth parameters of two olive rootstocks.Data showed that salinity decreases significantly some growth parameters such as shoot dry weight, root dry weight, shoot dry weight to root dry weight, and shoot elongation and decreasing amounts of all growth parameters by salinity in Zard rootstock were more than that of Mission. Shoot dry weight, leaf dry weight and root dry weight at 16 dS.m-1 salinity treatments were decreased 80, 80 and 69 percent respectively compared to control. Data also demonstrated that among different growth parameters, leaf aria had the most sensitivity to salinity and leaf relative water content(LRWC) had the lowest sensitivity to salinity. Base on the results, relative leaf aria was decreased 25 percent at 2.3 and 5.0 dS.m-1 salinity in Zard and Mission rootstock, respectively. Salinity status for 25 percent decrease of relative dry weight of these parameters were 2.8, 2.9 and 4.4 dS.m-1 in Zard rootstock and 5.3, 6.1 and 6.9 dS.m-1 in Mission rootstock respectively.Data analysis showed that there were a regression equation among salinity and some growth parameters such as relative leaf aria, leaf number, leaf water content and leaf chlorophyll. Data showed that the slope of regression fit line in Zard rootstock was more negative than Mission rootstock. These results confirmed that some variables such as relative leaf aria, leaf number, leaf water content and leaf chlorophyll content were more sensitive to salinity in Zard rootstock in compare to Mission rootstock.Data also showed that salinity status to for 25 percent decrees of relative leaf aria, leaf number, leaf water content and leaf chlorophyll content in Mission rootstock were 5.06, 5.51, 20.39 and 11.5 and for Zard rootstock were 2.33, 2.81, 15 and 8.61 dS.m-1 respectively. Data also indicated that 25 percent decrease in total relative dry matter were in 7.0 and 3.6 dS.m-1 salinity in Zard and Mission rootstooks, respectively. On the whole, evaluation of plant growth parameters and their sensitivity to salinity indicated that Mission rootstock had more tolerance to salinity and was recommendable to cultivation in salt affected soils.

There are many problems in yield, quality and and persistence regular bearing in olive trees, one of these problems is nutritional imbalances. This study carried out in order to evaluate nutritional status of olive orchards in Tarom region of Zanjan province. Samples of soil and leaf were taken from 79 olive orchards in June 2012 and 2013 and were analyzed by using appropriate laboratory methods. Deviation from optimum percentage (DOP) for each nutrient was calculated. The optimum concentration of nutrients in leaves of orchards with high yield for nitrogen (N), phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg), 1.8, 0.1, 1.2, 1 and 0.275 %, respectively and for manganese (Mn), zinc (Zn), copper (Cu) and boron (B), 20, 25, 4 and 30 mg/kg, respectively. The results showed that the average order of nutrients requirement according to DOP in the orchards is B>Mg>K>N>Zn>Mn>P>Ca>Cu. On the other hand all orchards with low yield, in terms of nutrient is in unbalanced status and nitrogen deficiency in 36%, potassium in 84%, magnesium in 93%, zinc in 35% and boron in 95% is predictable.

The recommended strategies in intensifying water shortage condition is changing the surface irrigation system to drip irrigation، in which case notification of the root system of mature trees for drip irrigation management is essential. The goal of this study was to investigate the effects of surface irrigation، automatic drip irrigation and traditional drip irrigation on olive tree root growth. The soil texture was sandy loam with 50% gravel. The fresh weight، dry weight and fresh volume of root were measured within 30 cm of tree under tree shadow area for 80 cm soil depth. The results showed that percent of fresh weigh was reduced 40% to 5% and 5 to 4 gr with increasing of depth and tree trunk distance to 240 cm، respectively. Also existence of gravel in soil was effective in root development، and fresh weigh and fresh volume density were decreased with increased of gravel. The olive root development was affected by irrigation system and dripper layout. The results showed that، changing of surface irrigation system to drip irrigation system for mature olive trees is possible; however، need to consider root growth system under previous irrigation system.

Different root water uptake models have recently been used. In this article, we use evapotranspiration data and soil water content data obtained from lysimeter measurements and root distribution in soil data obtained from olive tree to evaluate the accuracy of root water uptake models in predicting the soil water content profiles. Depth of lysimeter was 120 cm which was filled with clay-loam. Lysimeter recorded values of input and output of water and accurate value of evapotranspiration was also calculated. Soil water content distribution was measured using a TDR probe in lysimeter during the experiment. Feddes model with the root length density was used to account for the role of root distribution in soil. The flow equations were solved numerically with the measured evapotranspiration data as input, and the predicted soil water content profiles were compared with the measured profiles to evaluate the validity of the root water uptake models. The comparison showed that the average of relative error index for Feddes model was 10 %. Based on the results, about 90% of root uptake in olive tree happened at the depth of 40 centimeter.

Four cultivars of olive, Kalamata, Marri, Zard and Fishmi were obtained from Roodbar town and treated with two methods, natural and controlled fermentation with Lactobacillus plantarum</em> as a starter culture at 25°C for 100 days. HPLC analysis experiments were conducted during the whole study period. A higher level (1.08% w/w) of total acidity was produced in Fishmi cultivar especially in the natural fermentation (0.8-1.1 g lactic acid/ml) than in other cultivars. Individual organic acids were determined by HPLC. Quantitative changes of organic acids in olives showed (P<0.0l) an increasing pattern of lactic and acetic acids during fermentation, but decreasing levels of malic and citric acids were revealed. The highest level of lactic acid (1.1% w/v) was observed in Zard cultivar and the type of fermentation had no effect on acid production. Malic and citric acids gradually disappeared during 50 days of fermentation period and this change was faster for citric acid during controlled fermentation. Malic acid did not follow this pattern.