Showing 67 results for Growth
H. Naeemipour Younesi, H. Farhangfar , M.r. Asghari,
Volume 12, Issue 43 (4-2008)
Abstract
A total of 1256 records associated with body weight and Cashmere at different ages (birth and 3 and 9 months) obtained from 754 Cashmere goats were used to estimate the genetic parameters in southern Khorasan province during 2000- 2003. A set of univariate animal models including additive and maternal genetic effects and maternal permanent environmental effects as well as the fixed effects of year and month of birth, sex, birth type and dam age (linear and quadratic covariates) and kid age (linear and quadratic covariates) was fitted. Co/variance components were estimated by restricted maximum likelihood procedure using Powel algorithm in DFREML software. For the body weight at 0, 3 and 9 months, models two, one and three were recognized as the appropriate models. For these models, direct heritability estimates were found to be 0.09, 0.11 and 0.09, respectively. For birth weight and weight at month 9, the magnitude of c2 and h2m were 0.18 and 0.00, respectively. For average daily gains during 0-3 and 3-9 months of age, direct heritability based on the model one was 0.16 and 0.05, respectively. Direct heritability of Cashmere was found to be 0.02. Applying repeatability model, the estimates of heritability and repeatability of Cashmere were 0.16 and 0.53, respectively. Genetic trends for birth weight (0.0175kg/year) and weight at month 9 (0.02065kg/year) were positive and non-significant. A negative non-significant statistical genetic trend (-0.00537kg/year) was found for Cashmere during the period of time.
A.a. Besalatpour, M.a. Hajabbasi, A.h. Khoshgoftarmanesh , M. Afyuni1,
Volume 12, Issue 44 (7-2008)
Abstract
Total petroleum hydrocarbon (TPH) contaminations in soils may be toxic to human, plants and cause groundwater contamination. To achieve maximum TpH- reduction and to establish successfull stable vegetation cover in phytoremediation method, various criteria must be considered to choose the plants carefully. In this study, germination and subsequent growth of seven plants were tested in three soils with different petroleum contamination levels. Contamination treatments consisted of C0 (uncontaminated soil), C1 (1:1 w/w, uncontaminated: contaminated soil) and C2 (1:3 w/w, uncontaminated: contaminated soil). The experimental design was completely randomized split plots with three replications per treatment. The results showed that the presence of TPH in the soil had no effect on seed germination of agropyron, white clover, sunflower and safflower although canola seedlings were sensitive to these compounds and failed to produce dry matter yield (DMY) at the end of trial period. In contrast, seed germination of canola, puccenillia and tall fescue decreased in the petroleum contaminated soils. No reduction was found in DMY of puccenillia in contaminated soils (C1 and C2 treatments) compared to control however, the presence of TPH proportional to the contamination levels, decreased dry weight of sunflower and safflower. This reduction in growth and dry weight for tall fescue and agropyron was also observed in C2 compared to C1 treatment. Therefore, it seems that though agropyron, white clover, sunflower and safflower germinated well and the presence of TPHs in the soil treatments had no effect on their seed germination, they grew poorly. In contrast, grasses had poor seed germination but their subsequent growth and establishment in the contaminated soils was acceptable for subsequent phytoremediation trials.
M. Hajghani, M. Saffari, A. A. Maghsoudi Moud,
Volume 12, Issue 45 (10-2008)
Abstract
Soil salinity is an increasing environmental stress on crops in most areas of Iran since farmers use underground saline water for irrigation. In order to investigate the effects of salt stress on germination and seedling growth of safflower (Carthamus tinctorius L.), an experiment was conducted at two stages (germination seedling growth), using four levels of NaCl salinity (0, 5, 10, 15 ds/m), and four cultivars of spiny and non-spiny safflower ( a landrace from Isfahan bred cultivars of IL, LRV and PI). The design was factorial and completely randomized based on 3- replicates (CRD). Germination percentage, germination velocity index, root and shoot length, root and shoot dry weight, root to shoot dry weight ratio and salt tolerance index were measured at germination stage. In seedling growth stage, traits such as, stem length, number of leaves, chlorophyll index, root and shoot dry weight, root to shoot dry weight ratio and salt tolerance index were also measured. Results for both growth stages showed that salt stress decreased all the above mentioned traits, significantly, in all cultivars. Salinity × variety interaction at germination stage was also significant, compared to seedling growth stage. Salt tolerance index decreased significantly with increasing salinity at both stages, but differences between cultivars were not significant. Cultivars PI and IL were characterized as the tolerant ones at germination and seedling growth stages, respectively. It could be concluded that safflower cultivars responded differently to salinity in germination phase compared to seedling growth phase, and that safflower suffers more from salinity during germination stage.
R. Haddad, Gh. Garousi, M. Ghannadnia,
Volume 12, Issue 45 (10-2008)
Abstract
To study the effects of different combinations of auxin (IBA, NAA) and cytokinin (BAP, TDZ) regulators, basal salts (MS, WPM, NN) and gelling agents (Gelrite and Plant Agar) on the growth and development of seedless grape explants (cv. Bidaneh Soltani), a factorial experiment was conducted based on a completely randomized design. The number and length of grown shoots were analyzed as two main characteristics. Growth regulators and salts had significant effects (at %1) on the shoot proliferation. The highest number of shoots was observed on MS salts combined with BAP (2.2 mg/l) and IBA (0.5 mg/l) on the 18th days of culture. Compared to Plant Agar, Gelrite had a better effect on the normal growth of the shoots. Based on the new shoots, combinations of MS salts and hormones may be used for micropropagation of seedless grape cultivars in the in vitro condition.
F. Bahadori, K. Arzani,
Volume 12, Issue 45 (10-2008)
Abstract
Control of tree size is one of the main problems for which techniques to reduce vegetative growth and increase fruit quality and yield are important in the orchard management system. With this aim in mind, mature peach trees of the cultivars J. H. Hale and Red Skin grown on peach seedling at the Moghan agro industrial orchard were used. The effect of paclobutrazol soil treatments, (0,0.5 and 1.5 gr/tree) on experimental trees during the dormant periods in the 1996-97 was evaluated. The experiment was carried out in a split plot on the basis of completely randomized design with six replications. The effect of paclobutrazol on some vegetative growth and relative water content of leaves was studied. Results showed that paclobutrazol significantly reduced vegetative growth in the first year of application the total dry weight of pruning in treated trees was less than that of controls. The high level of paclobutrazol caused the most growth inhibition. On a commercial scale, paclobutrazol treatment would be able to give substantial benefits to peach growers by saving in pruning costs.
M Modaray Mashhood, J Asghari, A Hatamzadeh, M Mohamad Sharifi,
Volume 12, Issue 46 (1-2009)
Abstract
To compare the allelopathic potential of some Guilan province rice cultivars with allelopathically approved IRRI rice cultivars, a factorial experiment was conducted in completely randomized block design with 3 replications on the Experimental Farm of Agricultural College of Guilan University in spring 2005. Two factors including a) seven rice cultivars (traditional cultivars of Hashemi, Ali Kazemi, and Tarom and 2 modern cultivars of Khazar, and Dorfak and two IRRI cultivars of Dollar and IR64), and b) two types of planting, (including monoculture and mixed culture of each cultivar with Barnyardgrass) were used. A monoculture of Barnyardgrass was also used as a control. Growth rate (GR) and leaf area index (LAI) of Barnyardgrass were determined after 2, 4, 6, and 8 weeks of transplantation (WT), in mixed and monoculture treatments. In addition, after 3, 6, and 9 WTs the type and number of weeds in 1 m2 of each plot was determined. Rice plant samples were taken in 2, 4, 6, and 8 WTs, and were extracted in the Lab to be tested for germination for barnyardgrass and redroot pigweed seeds in Petri dishes. The filed research results showed that GR, LAI, number of weeds and yield of barnyardgrass grown with Dollar cultivar were lower than the others, which indicates higher allelopathic properties of this cultivar. Rice cultivars water extract evaluation of Petri dish also showed that Dollar cultivar has higher allelopathic potential than the other cultivars. Increasing the concentration of the water extracts increased the suppression of treated seedlings. From starting to geramination stage of the rice cultivars, allelopathic effects of the water extracts decreased. Leaves had the highest level of allelopathic potential in comparison to other organs. In other words, the pure extract of Dollar cultivar taken form samples in 2 and 6 WTs had the highest allelopathy potential among the cultivars and samples.
Z Amini, R Hadad, F Moradi,
Volume 12, Issue 46 (1-2009)
Abstract
The effects of irrigation, dry farming and drought treatments on the activities of antioxidant enzymes including superoxide dismutase, ascorbate peroxidase, catalase and peroxidase in barley leaves at different generative growth stages under field conditions were investigated. Three senescence parameters including chlorophyll, total soluble protein and rubisco large subunit protein loss, were also studied in order to compare our results to those reported by other researchers. The results showed that leaf relative water content (RWC), chlorophyll and total soluble protein and rubisco large subunit protein content declined with leaf age and the effect of water deficit. The activity of superoxide dismutase declined with the progress of the leaf age on all treatments but ascorbate peroxidase activity declined with leaf age only in irrigated (control) plants. There were no significant differences among developmental stages in catalase activity in control plants, while catalase activity declined in the water dry farming and drought stress conditions. Peroxidase activity increased with the progress of senescence for all of treatments in such conditions. Water deficit stress triggered increases in antioxidant enzymes activities. Results showed that among all studied enzymes, peroxidase has a key role in increasing resistance to oxidative stress on both the senescence stages and drought stress condition in Hordeum vulgare.
Z Daneshvar Ran, M Esfahani, M Payman, M Rabiei, H Samie Zadeh,
Volume 12, Issue 46 (1-2009)
Abstract
The effects of tillage methods and residual management on yield and yield components of rapeseed (Brassica napus L. CV. Hyola308) were evaluated after rice harvest. The experiment was carried out during 2004-2005 cropping season in a factorical arrangement of treatments at Rice Research Institute of Iran (RRII) in Rasht, in a Complete Randomized Block Design with three replications. Treatments included tillage in three methods: a) conventional tillage b) minimum tillage, and c) no tillage, and rice residue management in two manners: a) removing residues, and b) not removing residues. Plant traits such as grain yield, oil percentage and yield, plant density, plant height, the lowest pody branch height from soil surface, number of pods per plant, plant and weed dry weight, leaf area index (LAI) and crop growth rate (CGR) were measured. Results indicated that grain yield was affected by the tillage type. Also, the effect of tillage type on plant height, number of pods per plant, the lowest pody branch height from soil surface, and oil yield was significant. The effect of residual management and residual management interaction and tillage were significant on none of the traits except for weed dry weight. Economic analysis indicated that rapeseed planting in a field with rice residual and minimum tillage had a relative advantage of less production cost in spite of nearly 15 percent yield decrease compared to other methods.
M Hojati, N Etemadi, B Bani Nasab,
Volume 13, Issue 47 (4-2009)
Abstract
This study was conducted to evaluate the effects of paclobatrazol and cycocel on some quantitative and qualitative traits of zinnia. Seedlings were transplanted on Horticulture Department Farm , College of Agriculture, Isfahan University of Technology. The experiment was carried out in the framework of randomized complete block with 3 replications. Triats which were studied included plant height, leaf and flower number, lateral shoot number, flower diameter, lateral shoot lenght, leaf chlorophyl content, the period of the flowering, root fresh and dry weight, leaf area, root number, diameter and length, root and shoot carbohydrate. Results showed that cycocel at 1000 and 2000 ppm reduced height. Cycocel 2000ppm caused most lateral shoot and flower number and the lowest lateral shoot length. The lowest root fresh and dry weight, root number and length and shoot carbohydrate were obtained by cycoel 2000 ppm. Paclobutrazel at 30ppm resulted in the most leaf chlorophyl content. There were no significant differences between treatments related to the period of the flowering, flower diameter, leaf number and area, root diameter and carbohydrate.
A Esfahani, A Hoseyn Zade, J Asghari, M Naghizadeh, B Rabiee,
Volume 13, Issue 48 (7-2009)
Abstract
In order to evaluate the effects of sulphur fertilizer sources and amounts on growth indices and yield of peanut (Arachis hypogaea L. CV. NC2), a field experiment was conducted in Bandar Kiaashahr, Guilan province, Iran in 2004. The experiment was laid out in a factorial arrangement with two factors including sulphur sources (gypsum and single super phosphate) and sulphur rates (0, 30, 60 and 90 kg.h-1) in a completely randomized block design with three replications. Results showed that sulphur application greatly enhanced peanut growth and yield. The application of 90 kg.h-1 sulphur (in both forms) performed significantly better than the rest. The highest pod yield and grain yield were obtained in 90 kg.h-1 sulphur in gypsum form (6400 and 5200 kg.h-1, respectively). The highest LAI (6.6), CGR (20.2 g.m-2.12GDD-1) and PGR (16 g.m-2.12GDD-1) were obtained in 90 kg sulphur in the form of gypsum after 1142, 1142 and 1289 of accumulation, respectively. According to the results of the present experiment, it could be concluded that sulphur may considerably increase peanut grain yield and yield components. Thus, it could be expected that the application of 90 kg sulphur per hectare in the form of gypsum may result in better growth indices and higher grain yield of peanut.
A Esmaeili, F Nasrnia,
Volume 13, Issue 48 (7-2009)
Abstract
Deforestation has been recognized as one of the biggest environmental problems in the world. It is also one of the main elements of land productivity changes and one of the biggest factors which threaten world's environmental diversity. In this study, based on environmental Kuznets theory, factors which may affect deforestation have been investigated. Results obtained from 71 studied countries show that environmental Kuznets curve was not true for them. Population growth helps the speed of deforestation while higher rate of GDP growth decreases its rate. Institutions which help with the improvement of democracy, individual assets, civil right and political liberty can decrease the pressure on natural recourses and deforestation.
Z Taraz, B Dastar,
Volume 13, Issue 48 (7-2009)
Abstract
This experiment was conducted to compare the effects of Roxarsone (Rox) and Bacitracin methylen disalicylat (BMD) on the performance of broiler chicks. A control corn-soybean meal diet without growth promoter was formulated according to NRC (1994) recommendation for starter (0-21d) and grower (22-42d) periods. The control diet was also supplemented with Rox (50 mg/kg diet ) BMD (55 mg/kg diet) as well as the combination of Rox (50 mg/kg diet ) and BMD (55 mg/kg diet) in order to prepare 4 dietary treatments. Five replicate groups of 15 Ross 308 broiler chicks were assigned to each dietary treatment. Data was analyzed in a completely randomized design. Results of experiment indicated that individual supplementing of diet with Rox as well as BMD led to improved body weight gain and feed conversion ratio compared to the basal diet. However, those birds fed diet containing the combination of these two compounds had significantly higher body weight gain and lower feed conversion than other groups ( P<0.05 ). Neither Rox nor BMD had any significant effect on feed intake. Birds fed diets supplemented with Rox or BMD had better carcass composition than those fed Basal diet. Based on the present results, supplementing broilers diets with Rox leads to improved body weight gain and feed conversion ratio in broilers. However, supplementing broiler diets with combination of Rox and BMD has a more positive effect on the performance and carcass composition in broiler chicks.
H.r. Memari, E. Tafazoli, A. Kamgar-Haghighi, A. Hassanpour, N. Yarami,
Volume 15, Issue 55 (4-2011)
Abstract
Many experiments have been carried out to decrease the negative effect of drought stress and obtain suitable growth under water deficit conditions. Application of plant growth regulators (especially growth retardants) is one of the proposed methods. This study was conducted to investigate the effect of Cycocel application on growth of two olive cultivars (Shengeh and Roghani) under water stress condition. The design of experiment was completely randomized with six replications (Factorial arrangement). Treatments included irrigation intervals (2, 4, 6, 8 weeks) and Cycocel concentrations (0, 500,1000,2000,4000 mg per litter). Some indices such as height, chlorophyll, leaf area, root, and shoot weight (fresh and dry) were measured. Results indicated that interaction of C.C.C treatment and irrigation intervals on height of olive cultivars was not significant, probably due to the response of these cultivars to concentrations of C.C.C. Although drought stress decreased the number of leaves in both cultivars, the application of CCC (500 mg per litter) thwarted the adverse effects of drought stress. Cycocel increased chlorophyll content significantly (500 mg per litter in Roghani and Shengeh and 6 weeks irrigation interval). Cycocel application decreased leaf area, but in Shengeh cultivar increased leaf area in 6 week irrigation interval. Overall, the results indicated that the application of Cycocel with concentration of 500 mg per litter in 6 week irrigation intervals in both cultivars (Roghani and Shengeh) was the best treatment for controlling the adverse effects of drought. Also, results indicated that such changes were dependent on Cycocel concentration and drought level.
M. H.nazarifar, R. Momeni,
Volume 15, Issue 56 (7-2011)
Abstract
Deficit irrigation is one of the strategies used to obtain products with maximum profits in recent years. In this context, research on determining appropriate levels of deficit irrigation is essential. Since determining the different levels of performance through field experiments is difficult, the use of simulation models is a strategy through which we can examine the water balance data, simulate the growth process, and to study different managerial scenarios. The purpose of this study was validation and evaluation of CropSyst, a plant growth model, to determine suitable cropping patterns in deficit irrigation conditions. Applying three deficit irrigation scenarios in model, with values of 10%, 20% and 30% on six crops, fava bean, bean, wheat, potato, sunflower and rice, we concluded that the applied deficit irrigation of 10% to bean, potato and beans, 20% to sunflower and 30% to wheat had been suitable, and it is better not to apply deficit irrigation in rice. Also, since in final selection, the rate of water productivity is one of the basic criteria in each crop mentioned above, determining net benefit based on drop index (NBPD) per cubic meter showed that the most NBPD is related to bean with 6853 Rials per cubic meters and the lowest amount is related to sunflower with a value equal to 2809 Rials per cubic meters.
M. Rahmanian, H. Khodaverdiloo, M. H. Rasouli Sadaghiani, Y. Rezaie. Danesh, M. Barin,
Volume 15, Issue 58 (3-2012)
Abstract
Arbuscular mycorrhizae (AM) and Plant Growth Promoting Rhizobacteria (PGPR) associations are integral and functioning parts of plant roots. These associations have a basic role in root uptake efficiency as well as improvement of plant growth in degraded environments including heavy metals contaminated soils. This study was conducted to evaluate the effects of heavy metal-resistant soil microbe's inoculation on bio-availability of Pb and Cd in soil, plant growth as well as metal uptake by Millet (Pennisetum glaucum), Couch grass (Triticum repens) and wild alfalfa (Medicago sativa). A soil sample was treated by different levels of Pb and Cd (soil 1). Native microbial inoculums were obtained from alfalfa rhizosphere soils adjacent to Pb and Cd mines in Zanjan region (soil 2), then added with weight ratio of 1:5 (w/w) to soil 1. Host plants including millet, couch grass, and alfalfa were grown in pots and kept in greenhouse conditions. At the end of growing period, shoot dry matter and Pb and Cd concentrations in plant and soil were measured. Results indicated that plants yield and Pb uptake were significantly higher in non-inoculated treatments (p ≤ 0.05). However, Cd uptake by plants was greater in inoculated treatments (p ≤ 0.05). Couch grass showed the most accumulation potential of Cd and Pb among the studied plants.
M. Navabian, M. Aghajani,
Volume 16, Issue 60 (7-2012)
Abstract
In Guilan province, Sefidrud River, as the main source of irrigating rice in Guilan province, has been subjected to increasing salinity and a decreasing discharge because of decreasing in the volume of sefidrud dam, diverting water upstream and entering different sewages into the river. This research tries to determine optimum irrigation depth and intermittent periods in proportion to salinity resistance at different growth stages using optimization- simulation model. After calibration, Agro-hydrological SWAP model was used to simulate different growth stages of rice. Optimization results were obtained for managing fresh and saline intermittent water, 8-day intermittent period, for salinity of 0.747 dS/m in sensitive maturity stage and salinity of 3.36 dS/m in resistant vegetative, tiller and harvest growth stages. It is suggested that the depth of irrigation water be 1, 3, 3 and 5 cm for vegetative, tiller, maturity and harvest stages, respectively. Comparing managements of irrigation and saline based on the resistance of different growth stages to salinity and exploitation of irrigating water with a constant salinity during growth periods of the plant showed that irrigation management based on resistance of different growth periods of the plant to salinity causes rice yield to be improved by 23percent.
Y. Habibzadeh, M. R. Zardoshti, A. Pirzad, J. Jalilian,
Volume 16, Issue 60 (7-2012)
Abstract
To evaluate effect of different irrigation regimes and mycorrhizal fungi on the growth and yield of mungbean NM92 [Vigna radiata (L.) Wilczk], a field experiment was conducted in split plot arrangements using randomized complete block design (Irrigation after 50, 100, 150 and 200 mm evaporation from pan class A as main plots and mycorrhiza species, Glomus mosseae, G. intraradices and a non-inoculated treatment as sub-plots) with three replications at the Research field of Urmia university in 2009. Results showed that irrigation after 50mm evaporation from pan class A, and plant inoculated with G. intraradices produced the highest grain yield (1678.5 kg/ha and 1537.6 kg/ha, respectively), total dry weight, leaf dry weight, leaf area index, crop growth rate, relative growth rate and net assimilation rate. In Contrast, irrigation after 200 mm evaporation from class A pan and non-inoculated treatment produced the lowest grain yeild (1159.2 and 1301.9 kg/ha, respectively). Reducing the irrigation distance led to an increase in total dry weight, leaf dry weight, leaf area index, crop growth rate, relative growth rate and net assimilation rate. Despite lower grain yield in water deficit condition, AM fungi inoculation significantly reduced the effect of stress on grain yield. All inall, both mycorrhizae species significantly (P 0.05) increased the grain yield of mungbean under well-watered and water deficit conditions
H. Alinezhad Jahromi, A. Mohammadkhani, M. H. Salehi,
Volume 16, Issue 60 (7-2012)
Abstract
Nowadays, due to drought and water shortage, use of unconventional waters, particularly sewage, has become usual in agriculture whereas they often contain heavy metals. The present study was employed to evaluate the effect of urban wastewater of Shahrekord on growth, yield and accumulation of heavy metals (lead and cadmium) in balm (Melissa officinalis) as a medicinal plant with five treatments (0, 25, 50, 75 and 100 percent wastewater) and three replications in a completely randomized experimental design. The results showed that the highest shoot length, stem diameter and stem number, number of leaves and tillers are achieved in the treatment of 100 percent. The wet and dry weight of shoots and roots was highest in 100 % of wastewater. Oil percentage of the leaves was also the highest amount (1.23 %) in 100 % of wastewater. Accumulation of lead in roots and aerial parts and its transmission factor was not significant for the treatments. However, the highest concentration of lead in root (0.057 mg/kg) and shoots (0.013 mg/kg) was observed in 100 % of wastewater and the lowest one was related to zero percent of wastewater treatment. The lead concentration was less than the critical limit for all the treatments. The amount of cadmium was undetectable in all the plant samples. The results of this study demonstrated that urban wastewater of Shahrekord, in addition to providing water, increases plant growth and essential oil.
S. Eskandari , V. Mozafari,
Volume 16, Issue 60 (7-2012)
Abstract
A greenhouse experiment was conducted to study the effects of soil copper (Cu) and salinity on growth and chemical composition of two pistachio cultivars. A factorial experiment was carried out as a completely randomized design with three replications. Treatments consisted of four Cu levels (0, 2.5, 5, and 7.5 mg Kg-1soil as CuSO4.2H2O), five salinity levels (0, 800, 1600, 2400, and 3200 mg NaCl Kg-1 soil) and two pistachio cultivars (Badami-e-Zarand and Ghazvini). Results showed that salinity significantly decreased growth parameters. Application of 3200 mg NaCl Kg-1 soil decreased shoot and root dry weights, leaf area and stem height by 67, 72, 45 and 76 % respectively. Application of 7.5 mg Cu Kg-1 soil increased shoot dry weight and leaf area by 24 and 26% respectively. Morever, there was no significant difference between growth parameters of two pistachio cultivars, except for leaf area index. Salinity stress significantly decreased shoot and root P, k and Cu total uptake, and increased that of Na and Cl. Application of 5 mg Cu Kg-1 soil significantly increased shoot Cu uptake. Since total uptake of all elements for Badami cultivar was significantly higher than the Ghazvini, it could be concluded that the latter cultivar is probably more resistant to the saline conditions.
N. Besharat, A. Tajabadi Pour, V. Mozafari,
Volume 18, Issue 67 (6-2014)
Abstract
To study the effects of soil phosphorus (P) application on growth and water relations and nutrient concentration of pistachio seedlings (Badami-e-Zarand) under water stress, a greenhouse experiment was conducted. Treatments were arranged in a factorial manner as a completely randomized design with three replications. Treatments consisted of six P levels (0, 30, 60, 90, 120 and 150 mg P Kg-1 soil as H3PO4) and three irrigation intervals (2, 4 and 8 days). Results showed that as water stress increased, growth parameters significantly decreased. As irrigation interval was increased to 8 days, shoot and root dry weights, shoot/root ratio, leaf area and leaf number and stem height decreased. Photosynthesis parameters were significantly decreased by increasing water stress. Also, P and Zn concentrations decreased as irrigation interval increased. Analysis of variance indicated that P application had no significant effect on growth parameters, transpiration rate and photosynthesis. It seems that Olsen extractable P (5.35 mg kg-1 soil) was sufficient for optimum growth of pistachio seedlings and thus, no growth responses were observed from P application in this experiment. Application of phosphorus significantly increased P and decreased Zn concentrations.
