Pomology
Sadegh Azizifar; Vahid Abdossi; Rahmatollah Gholami; Mehrdad Ghavami; Ali Mohammadi Torkashvand
Abstract
Introduction: The availability of water for irrigating crops is one of the serious challenges at present and the future of the world. Drought stress has harmful effects on plant growth and productivity, though bringing some serious changes in plant physiology and biochemistry. Drought reduces plant growth ...
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Introduction: The availability of water for irrigating crops is one of the serious challenges at present and the future of the world. Drought stress has harmful effects on plant growth and productivity, though bringing some serious changes in plant physiology and biochemistry. Drought reduces plant growth and yield by having negative effects on plants water potential, cell division, photosynthesis activity, chlorophyll content, and protein synthesis. Although olive naturally tolerates drought, studies had shown that drought undermines its growth, yield and photosynthesis. Employing some appropriate transpiration-reducing approaches could induce olive tolerance towards water deficiency. In this regard, kaolin, through raising light reflection and diminishing the rate of transpiration, is able to lessen leaf temperature in the stressed plants. Salicylic acid (SA), as a strong signaling molecule in plants, regulates physiological and biochemical functions effective in defense mechanisms and also boosts biological and non-biological factors involved in augmenting plants.. The major roles of SA in drought- stressed plants are as follows: activation of antioxidant defense system, production of secondary metabolites, synthesis of osmolytes, optimization of mineral status and maintenance of proper balance between plant photosynthesis and growth. Although some information over effects of SA and kaolin individually on stressed plants is available, to the best of our knowledge, their simultaneous effects on plants under stressful conditions has not been investigated yet. Therefore, the present study was aimed to investigate different applications of SA and kaolin (i.e. individually and simultaneously) on field-grown olives under drought condition.Materials and Methods: This research was conducted in Dalahu Olive Research Station located in Kermanshah province. This experiment was designed as a factorial experiment in the form of a randomized complete block design with 3 replications. Factors included different foliar spraying (i.e. control, 1 mM SA, 2.5% kaolin, and a combination of them in the mentioned concentrations) and irrigation at three levels (i.e. 100, 75, and 50% of water requirement). Irrigation was performed based on three-day interval schedule according to the above method by measuring daily evapotranspiration and required volume of water by considering the plant coefficients of olives and by drip irrigation.Results and Discussion: Although olive tree is a drought-tolerant plant, drought diminished its yield. The results of this study demonstrated a decrease in total yield of olive trees due to water deficit in different years. In this regard, water deficit under high temperature and low atmospheric humidity are believed to bring about a reduction in yield of drought-stressed olive. The results of this research showed that the foliar application of SA and kaolin on olive trees led to a reduction in ionic leakage and malondialdehyde (MDA) and an increase in RWC, chlorophyll content, phenol and total yield, as compared to the control. Foliar application of SA caused a significant increase in proline content and total carbohydrates, while kaolin had no significant effect on aforementioned traits. It seems that a reduction in oxidative damage and an increase in yield of olive cultivars under different irrigations manifested several defense mechanisms induced by exogenous application of SA and kaolin. In this context, kaolin was found to protect leaves and fruits from harmful ultraviolet rays and this remarkably improves the performance of drought-stressed plants by a decrease in the ambient temperature of plants in order to mitigate deleterious effects of drought such as oxidative damage, chlorophyll degradation, and lowering RWC. These results have been substantiated for different olive cultivars at different parts of the world under this condition.In the present study, SA increased chlorophyll content, RWC, proline content, carbohydrate and total phenol; as a result, the yield of SA- treated plants was higher than that in control plants. Similarly, Brito et al (5) reported that applying SA on drought-stressed olive improved osmolate accumulation, photosynthesis activities, RWC and chlorophyll content. The accumulation of phenolic compounds in SA-treated plants is believed to protect plants against stressful conditions. Therefore, the role of SA and kaolin in alleviating drought in favor of enhancing plants yield represents their efficiency under such condition. In the present study, we also employed a combination of SA and kaolin and the results showed no synergistic function between them on most traits. Therefore, to reduce the effects of drought on olive tree, it is recommended to utilize SA or kaolin separately.
Rahmatollah Gholami; Isa Arji
Abstract
Introduction: Olive (Olea europaea L.) is an ever-green and drought-tolerant tree grown on regions with limited water resources to produce oil and table products. Due to existing appropriate environmental conditions in our country for its growing, and also considering public desperate needs to ...
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Introduction: Olive (Olea europaea L.) is an ever-green and drought-tolerant tree grown on regions with limited water resources to produce oil and table products. Due to existing appropriate environmental conditions in our country for its growing, and also considering public desperate needs to its oil product, olive is economically considered to be an important fruits to be cultivated. The problem of supplying sufficient water for irrigation olive orchards, due to serious threats of ongoing drought and reduction in water resources, is one of the main limiting factors on the way to develop olive industry in country. Accordingly, some suitable approaches like using tolerant cultivars, mulches, reduction of plant transpiration, plant growth regulators, and recently evaluating proper time for irrigation have been examined to increase efficiency of water use. According to this approach, irrigation schedule is designed mainly based on maintaining plant’s water status internally and regarding maximum level of water potential at particular stages of plant cycling, especially at time of lowest sensitivity of fruit growth to drought stress.
So far, many studies performed over effects of drought stress and water deficit on vegetable growth of olive under pot conditions. With respect to establishing olive orchards on different regions of country and appearing serious drought threats, it is imperative to investigate the effects of regulated irrigation deficit on all bearing fruit trees. Hence, determining the insensitive stages of fruit growth toward regulated irrigation deficit has been received great attentions in terms of economical yield. The purposes behind doing the current study were to investigate and compare effects of different regulated deficit irrigations on vegetative and reproductive parameters of olive grown under field conditions.
Materials and Methods: This study was aimed to investigate the effect of regulated deficit irrigation regime on vegetative, oil yield and oil content and water use efficiency of zard cultivar under field condition. This experiment was conducted in Javanmiri region (Geographical characters was longitude of 58˚, 45΄ E and latitude of 35˚, 34΄ N and the height of sea level 1215m) located in Kermanshah province. An experiment was conducted based on a randomized complete block design with three replications. Adult olive zard cultivar was uesd. Each experiment unit consists of three trees. Vegetative and reproductive traits were evaluated according to I.O.O.C. descriptors. five irrigation regimes including of full irrigation (as control), regulated deficit irrigation (100% of full irrigation during growing season and no irrigation during pit hardening), irrigation in three stages (before flowering, pit hardening and before harvesting), 60% of full irrigation (continuous deficit irrigation) and no irrigation (Rainfed). To evaluate the effect of irrigation regimes, some vegetative traits including current season growth and current season diameter, dry and fresh oil content, fruit mass percent, oil and fruit yield and water use efficiency were measured. Collected data were analyzed using SAS program.
Results and Discussion: Obtained results showed that the highest oil and fruit yield were observed at full irrigation and regulated deficit irrigation (100% of full irrigation during growing and no irrigation during pit hardening, but the lowest one found at Rainfed. The water use efficiency of oil yield of T3 was higher than 100ETc and other treatments.
In the arid and semi-arid as well as sub-tropical regions, water shortage is a normal phenomenon and seriously limits the agricultural potential. Therefore, under irrigation or rain-fed conditions, it is important for the available water to be used in the most efficient way. Regulated deficit irrigation is an optimizing strategy under which crops are allowed to sustain some degree of water deficit and yield reduction. During regulated deficit irrigation the crop is exposed to certain level of water stress either during a particular period or throughout the growing season. The main objective deficit irrigation is to increase water use efficiency (WUE) of the crop by eliminating irrigations that have little impact on yield, and to improve control of vegetative growth (improve fruit size and quality).
Conclusion: According to the results of this research, it can be concluded that regulated deficit irrigation had a significant effect on reproductive traits. Using regulated deficit irrigation improved pomological characteristics of olive including oil and fruit yield under drought stress and helped to save irrigation water in olive orchards.
Rahmatollah Gholami; Ali Asghar Zeinanloo; Fardin Ghanbari
Abstract
Introduction: Germplasm and reservation of genetical resources is the principal of plant breeding. Different techniques have been used to characterize olive diversity. Morphological criteria such as leaf, fruit, seed and growth behavior have been used to evaluate olive diversity, to determine the origin ...
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Introduction: Germplasm and reservation of genetical resources is the principal of plant breeding. Different techniques have been used to characterize olive diversity. Morphological criteria such as leaf, fruit, seed and growth behavior have been used to evaluate olive diversity, to determine the origin of olive trees as well. An evaluation of phenotypic diversity was used to discriminate olive cultivars with distinct morphological and pomological characters. Iran is one of the origins of olive in the world and it has considerable variation across Iran. Recently olive cultivation and orchard development has been encouraged in Iran. In this developmental project of olive culture, it is necessary to provide agreeable genotypes for cultivation.
Materials and Methods: The present experiment was carried out to identify and evaluate local olive genotypes in Kermanshah province during 2004-2005. Those were located in six locations in Kermanshah province. Their morphological characters and oil content were investigated according to IOOC descriptor. Local genotype identification in this regions was based on morphological characters (Vegetative and reproductive) such as leaf, fruit, seed and growth behavior evaluated at four different growth phases, including onset of dormancy, flowering, fruit set and fruit growth in 39 local olive genotypes olive trees.
Results and Discussion: The results of this study showed that there was a great variation among genotypes in Kermanshah province. Those variations was observed within and between regions. Significant correlation was observed between the fruit weight, with leaf width, stone weight and percentage of flesh, also significant correlation were observed between oil percentage in fresh fruit weight, with internode length and leaf width. Factor analysis showed that five factors with eigen values greater than one, explains the 69.62 percent of diversity. Among these factors, two biggest factors justified a high degree of diversity and genotypes were better than the other factors that were superior in terms of oil content and fruit weight. Generally it can be concluded that genotypes of Kermanshah province wide variety and traits are also high correlated with fruit weight and oil content and can properly use these genotypes and traits in breeding programs. Olea europaea L. represents one of the most important trees in the Mediterranean basin and the oldest cultivated plant. Among cultivated plants, the olive is the sixth most important oil crop in the world, presently spreading from the Mediterranean region of origin to new production areas, due to the beneficial nutritional properties of olive oil and to its high economic value. The Mediterranean basin is the traditional area of olive cultivation and has 95% of the olive orchards of the world. From the Mediterranean basin, olive cultivation is presently expanding into other regions. wide range of distribution, it is becoming increasingly urgent to identify plants into different ranges of distribution in the world to avoid cases of homonymy, synonymy and mislabeling so that a reliable classification of all varieties can be achieved without unnecessary confusion. In this paper, along with morphological characteristics the acquisition of additional information on biochemical markers is essential. This aspect represents a fundamental and indispensable step to preserve the main olive varieties and also to safeguard minor genotypes, in order to avoid a loss of genetic diversity. This research has focused on using morphological markers to characterize and identify olive varieties. Identification of different varieties using morphological characters (vegetative and reproductive) is one of the aims of the modern horticulture, because such a technique would greatly facilitate breeding programs and germplasm collection management.
Conclusion: According to the results of this research, it can be concluded that there is a great variation among different genotypes. Variation was observed within and between regions. High correlation between the fruit weight and leaf width, stone weight and percentage of flesh was observed, also high correlation between oil percentage in fresh fruit weight, with internode length and leaf width were observed. Factor analysis showed that five factors with eigen values greater than one, explains the 69.62 percent of diversity. Among these factors, two biggest factors justified a high degree of diversity and genotypes were better than others of the factors that were superior in terms of oil content and fruit weight. Generally it can be concluded that olive genotypes of Kermanshah province can properly use in breeding programs
Rahmatollah Gholami; Mohammad Gerdakaneh; Hojahatollah Gholami
Abstract
Introduction: Olive (Olea europaea L.) is one of the drought tolerant ever green fruit trees. Olive is an economically important species of the Mediterranean area, so understanding the mechanisms by which olive plants face drought stress under environmental conditions is essential for the improvement ...
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Introduction: Olive (Olea europaea L.) is one of the drought tolerant ever green fruit trees. Olive is an economically important species of the Mediterranean area, so understanding the mechanisms by which olive plants face drought stress under environmental conditions is essential for the improvement of olive yield and oil quality. Olive is one of the fruit trees which become important in the Iranian fruit industry at the near future. Mulch is an optimizing strategy under which crops are allowed to sustain some degree of water deficit and yield reduction. Increasing crop water-use efficiency (WUE) through water conservation in the soil is an important component of dry land farming. Mulching is among the water management practices for increasing WUE. Mulch is referred to as any material that is spread onto the surface of the soil for protection against solar radiation or evaporation. Different materials, such as wheat straw, rice straw, plastic film, grass, wood, and sand, are used as mulches.
Materials and Methods: This experiment was conducted to study the effect of irrigation interval and mulch on Pomological characteristics and yield of 11-years old Sevillana olive cultivar. A factorial experiment was carried out in Dallaho Olive Research Station at Sarepole located in Kermanshah province. Field experiment based on randomized complete block design with three replications and two factors (irrigation interval and mulch) were conducted in 2015. Each experiment unit consists of 4 trees and 108 trees were used. Irrigation treatments period for experiment were 3, 6 and 10 days interval and mulch treatments for experiment were polyethylene, organic materials and non-mulch (control). Geographical characters was longitude of 45˚, 51΄ E and latitude of 34˚, 30΄ N and the height of sea level 581m. The measured tree characteristics were: Fruit Weight, Pulp Fresh Weight, Pulp Dry Weight, Dry matter, Pulp/Pit ratio, Pit Length, Pit Diameter, Fruit Yield (kg/ tree) and Fruit Yield (kg/ hectare). Reproductive traits were determined by the methods of I.O.O.C.(2002). Collected data were analyzed using SAS program.
Results and Discussion: Obtained results showed that mulch and interval irrigation treatments had significant differences in Pomological traits so that mulch and 3 days interval irrigation treatments increased fruit weight, pulp fresh and dry weight, fruit moisture percent, fruit yield kg/ tree and kg/ hectare but fruit weight, pulp fresh and dry weight, fruit moisture percent and Fruit yield kg/ tree and kg/ hectare reduced by drought stress. Mulch application increased fruit weight, fruit length and diameter, pulp fresh and dry weight, fruit moisture percent and fruit yield. Mulch application improved Pomological characteristics such as fruit weight, pulp fresh and dry weight, fruit moisture percent, Fruit yield kg/ tree and kg/ hectare of olive Sevillana cultivar under drought stress and helped to save irrigation water in olive orchards. In the arid and semi arid as well as sub-tropical regions, water shortage is a normal phenomenon and seriously limits the agricultural potential. Therefore, under irrigation or rain-fed conditions, it is important for the available water to be used in the most efficient way. The proper irrigation interval can play a major role in increasing the water use efficiency and the productivity by applying the required amount of water when it is needed. On the other hand, the poor irrigation interval can lead to the development of crop water deficit and result in lower yield due to water and nutrient deficiency. Early in the season when plants are small, it is beneficial to encourage the roots to explore as much of the soil profile as possible. This maximizes nutrient uptake and stress tolerance later in the season. The effect of mulch on yield and its components have been reported in various studies. The effect of mulch on plant yield through changes in soil conditions that can change the soil temperature and soil moisture that influence on the growth and yield. The effect of mulch can be done through weed control, make favorable conditions of temperature and soil moisture, reduce leaching of nutrients and soil fertility, increase the efficiency of water use, increase availability of absorption of nutrients, increased root growth and control of diseases and pests.
Conclusion: According to the results of this research, it can be concluded that mulch and interval irrigation had a significant effect on reproductive characteristics. Using mulch improved Pomological characteristics of olive including fruit weight and yield per tree and hactar, fruit length and diameter, pulp fresh and dry weight, fruit moisture percent Under drought stress and helped to save irrigation water in olive orchards.
Rahmatollah Gholami; Isa Arji; Mohammad Grdkanh
Abstract
In order to determine the effect of irrigation interval and mulch on growth of olive an experiment was carried out in Dallaho Olive Research Station at Sarepole. A split plot experiment was used based on a completely randomized design with three replications and two factors (mulch and irrigation interval). ...
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In order to determine the effect of irrigation interval and mulch on growth of olive an experiment was carried out in Dallaho Olive Research Station at Sarepole. A split plot experiment was used based on a completely randomized design with three replications and two factors (mulch and irrigation interval). Each experiment unit consists of 4 trees. Land preparation was done in February 2005 in a 6048 squared meter area then tree planted. Pruning operation was done in next year. Mulch treatments for experiment were control, polyethylene and organic materials and irrigation treatments period for experiment were 3, 6 and10 days interval. Some growth traits including height, trunk diameter and current season growth were measured at the end of growth season. Collected data were analyzed with MSTATC program. Results showed that organic materials mulch and interval irrigation treatments had significant differences in height, trunk diameter and current season growth so that organic materials mulch and 3 days interval irrigation treatments increased height, trunk diameter and current season growth of olive trees. The interaction effect between mulch and irrigation treatments was significance. So that 3 days interval irrigation and organic materials mulch had the highest height, trunk diameter and current season growth. 6 days interval irrigation supplemented with mulch treatment had more significant effect on these traits compared to 3 days interval irrigation alone.
Rahmatollah Gholami; Kazem Arzani; Isa Arji
Abstract
An experiment was conducted to determine the effect of paclobutrazol (PBZ) and different irrigation amount on growth of aerial parts, leaf minerals and root performance in young olive plants cv. ‘Manzanillo’ in the Department of Horticulture, Faculty of Agriculture, Tarbiat Modarres University in ...
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An experiment was conducted to determine the effect of paclobutrazol (PBZ) and different irrigation amount on growth of aerial parts, leaf minerals and root performance in young olive plants cv. ‘Manzanillo’ in the Department of Horticulture, Faculty of Agriculture, Tarbiat Modarres University in 2000. A split plot experiment in time was used based on a completely randomized block design with four replications. The aim of this experiment was to determine the effect of water irrigation amount reduction on Manzanilo olive response. Treatments were 60, 70, 80, 90 and 100 % evapotranspiration (ETp) and 60% with 0.25 g a.i /pot paclobutrazol (PBZ). Control plants were used as reference to determine evapotranspiration (ETp). Some characteristics such as root, leaf and shoot fresh and dry weight, leaf area, leaf number, plant height, root length and mineral content were measured. Results indicate that root, leaf and shoot fresh and dry weight, leaf area, leaf number, plant height and N and K amount were increased with increasing of water amounts. No differences were found in measured characters between 90 and 100% (ETp) so a 10 percent saving in water was occurred. Result showed that pbz treatment after 45 days reduced shoot growth, leaf and shoot fresh and dry weight, leaf area, plant height, root length and N and K content. Although, PBZ treatment increased root to shoot fresh and dry weight ratio and increased root diameter. In case of water shortage pbz treatment is able to ameliorate the effect of water stress.
