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.
Isa Arji; Banafshe Hassani; Hooshang Ghamarnia
Abstract
Introduction: Since Iran is located in arid and semi-arid region of the world, so consumption and saving of water must be taking into account. Water is often a valuable natural resource, thus proper application methods - for increase water efficiency can be very important. Regulated deficit irrigation ...
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Introduction: Since Iran is located in arid and semi-arid region of the world, so consumption and saving of water must be taking into account. Water is often a valuable natural resource, thus proper application methods - for increase water efficiency can be very important. Regulated deficit irrigation (RDI) is one of the most important methods to increase water use efficiency and fruit quality. Apple is one of the most important fruit trees from economical point of view. Studies showed that regulated deficit irrigation led to growth reduction in apple trees and sometimes fruit quality increased. The aim of this study was to evaluate the effect deficit irrigation on vegetative growth and fruit quantity and quality of Golden delicious apple trees in Gahvareh region of Kermanshah province.
Materials and Methods: This experiment was conducted on 10 years old Golden delicious apple trees in a randomized complete block design with 5 irrigation treatments and three replications during 2006. Three apple trees assigned to each experimental unit. Irrigation treatments were: T1= early deficit irrigation (40% water requirement), T2= early deficit irrigation (60% water requirement), T3= late deficit irrigation (40% water requirement), T4=late deficit irrigation (60% water requirement), T5=control (C) (100% water requirement). Early deficit irrigation starts 55 days after full bloom (15th Jun) and continued 60 days (16th Aug), while late deficit irrigation starts 115 days after from full bloom (16th Aug) and continued 40 days near to harvesting time (23th Sept). Control trees were full irrigated based on water requirement, which calculated based on national water document of Iran and irrigation amount was calculated based on the following formulas: Q=0.0184.L.H3/2
Where Q is volumetric flow rate (liter/Second), L is parshall flume crown length (cm) and H is water height (cm). Irrigation time was calculated based on national water document of Iran and volumetric flow rate as this formula Q.t = di.a, where Q is volumetric flow rate (liter/Second), t is time based on second, di is net water requirement and a is irrigated area. To evaluate irrigation effects some vegetative (shoot growth and trunk cross sectional area); reproductive (fruit volume, fruit weight and yield) and quality (Total soluble solid, total sugar, nitrogen, phosphorous, potassium and calcium) traits were measured.
Results and Discussion: Results showed that deficit irrigation had no effect on trunk cross sectional area, but shoot growth was affected significantly by deficit irrigation by. So, regulated deficit irrigation (RDI) can be used to control excessive vegetative growth in apple trees. There were no significant differences of fruit volume and weight of trees under deficit irrigation than the control exception to secondary 40% treatment. Fruit yield did not have significant differences under early and late 60% treatment in compare to the control. Where yield reduction was only 4 and 8 % in late and early 60% deficit irrigation respectively in compare to full irrigated trees. Water deficit had positive effect on qualitative traits of apple fruit, So that total soluble solids (TSS) and total sugar concentration (TSC) of fruit were higher in trees subjected to deficit irrigation as compared to the control. Regulated deficit irrigation led to 7-18% and 1.8-15% increase in total soluble solid and total sugar content in compare to full irrigated trees. Relative water content (RWC) was significant based of the time of applying deficit irrigation. Deficit irrigation did not have significant effect on fruit minerals such as P and K in compare to the control, but N content had significant reduction in deficit irrigation treatments in compare to the control and Ca fruit content of control trees had significant different in compare to trees were subjected to early deficit irrigation (40% of water requirement).. RDI favored reproductive growth over vegetative growth by suppressing vegetative growth. Water saving in deficit irrigation was 41, 27, 18 and 12 percent in early 40%, 60% and late 40% and 60% of water requirement respectively. Therefore, regulated deficit irrigation (RDI) applied with good intensity and at the right time not only reduces the amount of water used but also increased the yield performance and some fruit qualitative properties. RDI can be used to control vegetative growth and improve yield efficiency of apple trees.
Conclusions: Regulated deficit irrigation is more effective for water saving with a higher WUE and not reduction of fruit quality rather than to contain excessive vegetative growth in apple trees. Therefore, RDI can be suggested for commercial use and can be adapted successfully for the regions in similar soil and climate conditions. In general water deficit irrigation can cause increases quality of fruit in the Golden Delicious apple trees. Therefore, it is recommended to apply 60% of the water requirement for this cultivar.
Nariman Rashidi; Isa Arji; Mohammad Gerdakaneh; Abdolkarim Kashi
Abstract
In order to investigate effect of organic manure and super absorbent on physiological and biochemical traits of potato (Solanum tubersum, cv Marfona), a split plot experiment was conducted as randomized complete block design with three replications at Research Farm, Agriculture College, University of ...
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In order to investigate effect of organic manure and super absorbent on physiological and biochemical traits of potato (Solanum tubersum, cv Marfona), a split plot experiment was conducted as randomized complete block design with three replications at Research Farm, Agriculture College, University of Razi in 2010. Main factor included two levels of super absorbent A200 (0 and 70 Kg/ha,) and split plot included nine levels (0, chemical fertilizer (according to soil test), granule chicken manure (1000 kg/ ha), common chicken manure (12 ton/ha), soil mix (1000 kg/ha), cow manure (20 ton/ha), vermicompost (20 ton/ha), compost (20 ton/ha) and tea compost (soaking tubers and spraying at four times). Investigating physiological traits such as leaf chlorophyll index, chlorophyll florescence and stomata conductance showed that only leaf chlorophyll index was affected by superabsorbent (P < 0.01) and organic manure (P < 0.05), while stomata conductance wad significant under it’s interaction effect at (P < 0.05). Quality and biochemical traits show that phosphorous amount of tuber was significant in superabsorbent treatment in compare to control. Crude oil percentage, protein, fiber, starch, sugar, nitrogen, phosphorous and potassium content were not affected by organic manure. The highest amount of oil and fiber were obtained under compost and cow manure respectively. Sugar and nitrogen content were high under cow manure treatment. The highest amount of potassium and phosphorous content were belonging to chicken and Khakparvar manure respectively.
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.
Farideh Sheikhmoradi; Isa Arji; Akbar Emaeili; Vahid Abdossi
Abstract
Abstract
Water deficit and consecutive droughts have lead to drought stress in most parts of the world recently. We need prepare a good program to use better available water. Different material can be used to increase water use efficiency. Super absorbent is one of the materials used around the world. ...
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Abstract
Water deficit and consecutive droughts have lead to drought stress in most parts of the world recently. We need prepare a good program to use better available water. Different material can be used to increase water use efficiency. Super absorbent is one of the materials used around the world. These materials absorb water in the soil so that reserved water is usable by plant in the time of drought stress and they can reduce stress and lead to prevent yield loss. So that an experiment was conducted to evaluate effects of different super absorbent and irrigation cycles on lawn. A split plot experiment based on randomized block design with three replication was used so that irrigation cycles and super absorbent amounts used as main plots and subplots respectively. 4 irrigation periods (1, 2, 4 and 6 days) and 4 super absorbent amounts (0, 20, 25 and 30 g/m2) were used as experimental treatments. One day irrigation interval and zero super absorbent amounts were used as control. Lawn water requirement calculate by evaporation from a pan class A. Results shown that super absorbent amount had significant effect at 1% and 5% level on shoot height, total chlorophyll and plant density but had significant effect on root fresh and dry weight, shoot fresh and dry weight, root developing. Rigidity, Elasticity and performance quality was higher for 30 g/m2 of super absorbent amount at one and two day's irrigation cycle interval in compare to other treatments. Experiment results showed that lawn performance was higher in 30 g/m2 of super absorbent amount at two days irrigation cycle than the others and had 50% water saving in compare to one day irrigation interval.
Keywords: Irrigation cycle, Lawn, Qualitative characteristics, Super absorbents
