@article{ author = {Zomorodian, A. and Dadashzadeh, M.}, title = {Indirect and Mixed Mode Solar Drying Mathematical Models for Sultana Grape}, abstract ={Many research studies have been performed on forced convection (active) solar dryers for fruit and vegetables. A short survey of these showed that applying the forced convection solar dryer not only significantly reduced the drying time but also resulted in many improvements in the quality of the dried products. Active indirect and mixed-mode thin layer solar drying experiments were conducted on Sultana grapes. A combination of a solar air heater and a cabinet dryer was designed, constructed and tested for this product in the Agricultural Engineering Department at Shiraz University, Iran. Three air flow rates (0.085, 0.126 and 0.171 m3 s-1) and two types of drying systems (indirect and mixed-mode) were adopted. The south wall of the drying chamber was covered by a sheet of glass for mixed-mode and the glass sheet was covered with a thick sheet of cloth for an indirect solar drying system. Seven well-known thin layer drying models were used separately to fit the mixed-mode and indirect type experimental data for Sultana grapes. For experimental indirect data, the Modified Page model (r= 0.998, χ2= 0.000241) and for experimental mixed-mode data, the Page model (r= 0.999, χ2= 0.000169) showed the best curve fitting results with highest r (correlation coefficient) and lowest χ2 (reduced chi-square) values. The constants in these models explain the effects of drying parameters, air velocity and temperature. To take account of these effects, the best correlation equations between the constants and drying parameters were also introduced using multiple regression analysis.}, Keywords = {Cabinet solar dryer,Thin layer mathematical model}, volume = {11}, Number = {4}, pages = {0-0}, publisher = {Tarbiat Modares University}, url = {http://jast.modares.ac.ir/article-23-10198-en.html}, eprint = {http://jast.modares.ac.ir/article-23-10198-en.pdf}, journal = {Journal of Agricultural Science and Technology}, issn = {1680-7073}, eissn = {2345-3737}, year = {2009} } @article{ author = {Afzalinia, S. and Roberg, M.}, title = {An Extended Octagonal Ring Transducer for the Compression Chamber of a Large Square Baler}, abstract ={An extended octagonal ring (EOR) transducer was designed and developed to measure forces inside the compression chamber of a large square baler in different directions. The transducer was calibrated by applying forces in three directions simultaneously and independently. The sensor revealed excellent linearity along with small cross sensitivities. Horizontal and vertical primary sensitivities of the sensor were 1,479.7 and 1387.8 μVkN-1V-1, while horizontal and vertical cross sensitivities were 0.64 and 2.85% of the sensor primary sensitivities, respectively. The sensor was used to measure the forces inside the compression chamber of a large square baler in different directions.}, Keywords = {Calibration,Cross sensitivity,Extended octagonal ring,Force transducer,Large square baler}, volume = {11}, Number = {4}, pages = {377-389}, publisher = {Tarbiat Modares University}, url = {http://jast.modares.ac.ir/article-23-11928-en.html}, eprint = {http://jast.modares.ac.ir/article-23-11928-en.pdf}, journal = {Journal of Agricultural Science and Technology}, issn = {1680-7073}, eissn = {2345-3737}, year = {2009} } @article{ author = {MajnounHosseini, N. and Siddique, K. and Palta, J. and Berger, J.}, title = {Effect of Soil Moisture Content on Seedling Emergence and Early Growth of Some Chickpea (Cicer arietinum L.) Genotypes}, abstract ={At the crop level, the drought stress accounts for most variations in yield. A controlled glasshouse investigation at day/night temperatures of 22/15°C based at Perth City, Western Australia was performed (in 2006) to assess the influence of different soil moisture contents (field capacity percentage basis) on emergence as well as early plant growth in twenty chickpea genotypes. The experiment was laid out in split plot design with soil moisture con-tent as the main treatment and genotype as sub-treatment. Significant differences (P < 0.001) as regards plant emergence and early growth were observed among different soil moisture contents (from 100 to 50, then to 25% field capacity). This brought about a quad-ratic reduction in mean emergence percentage, delayed the first day to emergence and sup-pressed the early growth in all the chickpea genotypes. Highly significant differences were also noticed among the genotypes for mean emergence percentage, first day to emergence, plant height, leaf area, total above-ground biomass (plant size) as well as specific leaf area. Significant interaction effect of soil moisture contents and genotypes were observed only for some of the characteristics. Inverse relationship between first day to emergence with plant height (r= - 0.87**) and above-ground biomass (r= -0.84**) were observed, indicating that the chickpea genotypes which emerged sooner produced greater plant size. Seed size and density were found to have no relationship with plant size. Although the Kabuli types on av-erage germinated faster and produced larger plants as opposed to the Desi types under the limited soil moisture content, but there was no consistency observed among the chickpea genotypes. Susceptibility of the genotypes to limited soil moisture condition was shown through relatively longer delays in time to emergence (lower germination rate) and reduc-tion in seedling parameters as compared to the resistant genotypes. Final average above-ground biomass (plant size) and plant height under the limited soil moisture content, as op-posed to adequate moisture level (F. C. 25% vs. 100%), were reduced 79-85% in Kabuli and 77-79% in Desi types, respectively.}, Keywords = {Chickpea genotypes,Early seedling growth,Emergence percentage,First day to emergence,Soil moisture content}, volume = {11}, Number = {4}, pages = {401-411}, publisher = {Tarbiat Modares University}, url = {http://jast.modares.ac.ir/article-23-10807-en.html}, eprint = {http://jast.modares.ac.ir/article-23-10807-en.pdf}, journal = {Journal of Agricultural Science and Technology}, issn = {1680-7073}, eissn = {2345-3737}, year = {2009} } @article{ author = {PasbanEslam, B.}, title = {Evaluation of Physiological Indices, Yield and its Components as Screening Techniques for Water Deficit Tolerance in Oilseed Rape Cultivars}, abstract ={Water deficit is an important factor limiting crop production worldwide. Drought stress can be managed by improving the availability of soil moisture conserved and selecting drought tolerant genotypes. Several physiological indices including stomatal conductance (Kl), relative water content (RWC), leaf temperature (Tl) and crop temperature stability (CTS) along with yield, its components and seed glucosinolate content were measured in five oilseed rape genotypes of Brassica napus L. (Talayeh, Fornax, Okapi, Regent Cobra and SLM046) under non-stress and water deficit conditions imposed from late flowering (80% flowering) to maturity in a loam soil at the Research Center for Agriculture and Natural Resources of East Azarbaijan, Iran (462E, 3758N) over two successive years (2001-2003). According to the significant decrease of Kl and RWC and significant increase of Tl caused by water deficit in both years, it seems that, these indices could reflect the drought effects occurring from late flowering in oilseed rape crops. Kl and Tl values also differed significantly among genotypes and therefore these indices could be used to screen oilseed rape genotypes for tolerance against late season drought. Water deficit significantly decreased the number of pods per plant and seed yield in Talayeh and Fornax. Significant positive correlation was observed between these traits during both years (r=0.88 and 0.89, respectively). It seems that when water deficit occurs from late flowering, decreased seed yield mainly via decreasing number of pods per plant is observed in oilseed rape. Okapi and SLM046 showed lower Tl value (30.6 and 29.7C, respectively), a higher Kl value (0.350 and 0.355 cm s-1 respectively) and seed yield (5,241 and 5,245 Kg ha-1, respectively) under the water deficit condition. Okapi and SLM046 are therefore more suitable for cultivating in areas with late season water deficit stress.}, Keywords = {Oilseed rape,Leaf temperature,Relative water content,Seed yield,Water deficit}, volume = {11}, Number = {4}, pages = {413-422}, publisher = {Tarbiat Modares University}, url = {http://jast.modares.ac.ir/article-23-6670-en.html}, eprint = {http://jast.modares.ac.ir/article-23-6670-en.pdf}, journal = {Journal of Agricultural Science and Technology}, issn = {1680-7073}, eissn = {2345-3737}, year = {2009} } @article{ author = {Karimi, S. and Khajali, F. and Rahmani, H. R.}, title = {Chemical and Non-chemical Molting Methods as Alternatives to Continuous Feed Withdrawal in Laying Hens}, abstract ={An experiment was conducted to evaluate the effectiveness of chemical and non-chemical molting methods as compared to conventional feed removal methods with respect to the physiological response and postmolt performance in Hy-line W36 laying hens. One hundred and eight 78-week-old hens were distributed among 27 groups of four birds and placed in cages so that the mean body weight of each cage was very similar. Three adjacent cages were considered as a replicate and 3 such replicates were assigned to each treatment. There were three treatments (molting procedures). Treatment 1 was continuous feed removal (CFR) and considered as the control. Hens on treatment 2 (T2) were fed finely ground delinted whole cottonseed as the sole feed ingredient and dietary vitamin and macro and microelement levels were maintained according to Hy-line W36 guideline specifications. Birds on treatment 3 (T3) received a layer diet containing 5,000 ppm Zn and fed at the rate of 50 g b-1 d-1. The results indicated that hens subjected to CFR, whole cotton seed and zinc supplemented diet went out of production on Day 6, Day 7 and Day 14, respectively. Continuous fasting and feeding whole cottonseed as molting programs resulted in significantly (P< 0.05) lower body weight and serum T3 concentrations but higher heterophil to lymphocyte (H:L) ratio and hematocrit, compared to the zinc method when measured on Day 7. Birds that received molt diet supplemented with zinc produced heavier eggs postmolt (P< 0.05) in comparison to other treatments but the egg production, egg mass and egg quality criteria were not different among the treatments.}, Keywords = {Cotton seed,Fasting,Laying hens,Molting,Zinc}, volume = {11}, Number = {4}, pages = {423-429}, publisher = {Tarbiat Modares University}, url = {http://jast.modares.ac.ir/article-23-5979-en.html}, eprint = {http://jast.modares.ac.ir/article-23-5979-en.pdf}, journal = {Journal of Agricultural Science and Technology}, issn = {1680-7073}, eissn = {2345-3737}, year = {2009} } @article{ author = {Askari, F. and Sefidkon, F.}, title = {Chemical Composition and Antimicrobial Activity of the Essential Oil of Pimpinella puberula (DC.) Boiss.}, abstract ={In this study, the aerial parts of Pimpinella puberula were collected from Ramhormoz and Mashhad (Khuzestan and Khorasan Provinces) at the vegetative, flowering and seeding stages. Essential oils from the whole aerial parts as well as stem/leaf, inflorescence, unripe and ripe seeds, were isolated by hydro-distillation. The yields of essential oil obtained from the Ramhormoz samples were 0.49%, 0.31%, 3.81%, 6.01% and 1.80% w/w, and from those from Mashhad were 0.96%, 0.87%, 3.59%, 6.94% and 4.96% w/w, respectively. The oils from different parts of plant were also analyzed by GC and GC/MS. Limonene was the major constituent in all the oils (21.7%-82.4%), followed by pregeijerene (14.6%-55.4%) and geijerene (7.2%- 11.7%). Methyl eugenol and elemicine, however were only found in the Ramhormoz oil samples. The antimicrobial activity of the oils was determined using the disk diffusion method against Gram positive bacteria (Bacillus subtilis, Bacillus cereus, Micrococcus luteus and Staphylococcus aureus), Gram negative bacteria (Yersinia entrocolitica, Klebsiella oxytoca, Serratia marcescens, Escherichia coli and Pseudomonas aeruginosa) and yeast (Candida albicans). Results showed a significant difference between Gram positive and Gram negative bacteria in their susceptibility to the oil, although Gram positive bacteria were more susceptible to the antimicrobial activity of P. puberula oil. In addition, the antimicrobial activity of samples collected from Ramhormoz were more than of those from Mashhad.}, Keywords = {Antimicrobial activity,Essential oils,Limonene,Pimpinella puberula,Pregeijerene}, volume = {11}, Number = {4}, pages = {431-438}, publisher = {Tarbiat Modares University}, url = {http://jast.modares.ac.ir/article-23-7757-en.html}, eprint = {http://jast.modares.ac.ir/article-23-7757-en.pdf}, journal = {Journal of Agricultural Science and Technology}, issn = {1680-7073}, eissn = {2345-3737}, year = {2009} } @article{ author = {Zeinali, H. and Tabaei-Aghdaei, S. and Arzani, A.}, title = {A Study of Morphological Variations and Their Relationship with Flower Yield and Yield Components in Rosa damascena}, abstract ={ABSTRACT Rosa damascena has attracted considerable attention in horticulture, biochemistry and in pharmacology because of the fragrance of the flowers and the high content of its bio-logically active substances. There is limited information available on factors controlling flower yield and its components. The present study reports an investigation on flower yield and the various factors affecting it, in Iranian Rosa damascena using sixteen geno-types collected from different regions in Iran. These genotypes were planted at Isfahan Agriculture Research Center, using a randomized complete block design with three repli-cations in 2005. Twelve yield determining characters including flower yield per plant, number of flowers per plant, fresh flower weight, plant height, canopy diameter, length and width of bud, number of petal per flower, length and width of receptacle, fresh weight of petal as well as flowering period were recorded. Rosa damascena genotypes sig-nificantly varied for all the traits except for the fresh weight of petals per flower. Pheno-typic and genotypic coefficients of variation for flower yield per plant (48.03%, 36.49%), number of flowers per plant (40.65%, 26.99%), number of petals per flower (37.56%, 32.31%) were higher than the coefficients for other tested traits. Cluster analysis revealed that Khuzestan and Shiraz 2 genotypes were the most related ones, while the most inde-pendent ones were the western and eastern Azerbaijan genotypes. Results of stepwise re-gression analysis showed that 90 percent of total variation of flower yield per plant could be explained by the number of flowers per plant. This suggested that number of flowers per plant is the most important component determining flower yield per plant. According to principle component analysis, parents with a high standing of the following traits: fresh weight of flower, number of petals per flower and bud width, may well be employed for hybridization in a breeding program. Regression and cluster analyses proved to be the appropriate multivariate analyses for an identification of Rosa damascena genotypes pos-sessing the desirable characters for hybridization to develop improved cultivars.}, Keywords = {Cluster analysis,Hybridization,Receptacle,Rosa damascena,Stepwise regression}, volume = {11}, Number = {4}, pages = {439-448}, publisher = {Tarbiat Modares University}, url = {http://jast.modares.ac.ir/article-23-2169-en.html}, eprint = {http://jast.modares.ac.ir/article-23-2169-en.pdf}, journal = {Journal of Agricultural Science and Technology}, issn = {1680-7073}, eissn = {2345-3737}, year = {2009} } @article{ author = {Arzani, K. and Sherafaty, A. H. and Koushesh-Saba, M.}, title = {Harvest Date and Post Harvest Alkaline Treatment Effects on Quantity and Quality of Kashmar, Iran, Green Raisin}, abstract ={The yield and quality features of raisin are affected by various factors especially har-vest date and dipping solutions. Combinations of different harvest date (four harvest dates) and post harvest alkaline emulsion (three alkaline solutions) were tested in Vitis vi-nifera L. cv ‘Paycamy’ green raisin production in Kashmar, Khorasan Province of Iran. Such raisin quantitative and qualitative characteristics as: yield, drying ratio (fresh: rai-sin yield), raisin wastes, sugar content, price, color, homogeneity of color, raisin size, alka-line solution residues and surface texture of raisin (shrinkage) were assessed. Harvest date results showed that grape °Brix and raisin sugar content increased from 15.5 to 21 and 53% to 62% respectively. In addition, fourth harvest yield increased raisin yield up to 30% as compared to the first harvest. The amount of wastes resulted from decayed berry in the fourth harvest was higher than those for the other harvest dates, but such qualita-tive traits as color, size and texture softness improved through further fruit ripening. In-teraction effect of alkaline solution and harvest date on price and raisin size (number of raisins per 100 g) were significant (P< 0.01). Alkaline solution affected raisin waste, the differences among post harvest treatments being significant. The color of raisin was not affected by alkaline solution but it was steadily improved with each succeeding harvest date.}, Keywords = {Grape (Vitis vinifera L. cv. Paycamy),Green raisin,Harvest time,Post harvest treatments,Raisin quality}, volume = {11}, Number = {4}, pages = {449-456}, publisher = {Tarbiat Modares University}, url = {http://jast.modares.ac.ir/article-23-7121-en.html}, eprint = {http://jast.modares.ac.ir/article-23-7121-en.pdf}, journal = {Journal of Agricultural Science and Technology}, issn = {1680-7073}, eissn = {2345-3737}, year = {2009} } @article{ author = {Ahmadi, M. M. and Ayyoubzadeh, S. A. and MontazeriNamin, M. and Samani, J. M. V.}, title = {A 2D Numerical Depth-averaged Model for Unsteady Flow in Open Channel Bends}, abstract ={The purpose of this paper is to present a 2D depth-averaged model for simulating and examining unsteady flow patterns in open channel bends. In particular, this paper proposes a 2D depth-averaged model that takes into account the influence of the secondary flow phenomenon through calculation of the dispersion stresses. The dispersion terms which arose from the integration of the product of the discrepancy between the mean and the actual vertical velocity distribution were included in the momentum equations in order to take into account the effect of the secondary current. This model used a time-splitting method for solving advection, diffusion and other momentum equation terms. The proposed model uses an orthogonal curvilinear coordinate system efficiently and accurately to simulate the flow field with irregular boundaries; it also used a finite volume projection method approach for solving the governing equation in a staggered grid. Two sets of experimental data were used to demonstrate the model's capabilities. The comparison of the simulated water surface elevation with the measurements shows good agreement and indicates that inclusion of the dispersion terms improved the simulation results.}, Keywords = {Bend,Meander,Numerical models,Open channels,Two dimensional model,Unsteady flow}, volume = {11}, Number = {4}, pages = {457-468}, publisher = {Tarbiat Modares University}, url = {http://jast.modares.ac.ir/article-23-9822-en.html}, eprint = {http://jast.modares.ac.ir/article-23-9822-en.pdf}, journal = {Journal of Agricultural Science and Technology}, issn = {1680-7073}, eissn = {2345-3737}, year = {2009} } @article{ author = {Mousavi, S. F. and Mostafazadeh-Fard, B. and Farkhondeh, A. and Feizi, M.}, title = {Effects of Deficit Irrigation with Saline Water on Yield, Fruit Quality and Water Use Efficiency of Cantaloupe in an Arid Region}, abstract ={High groundwater salinity, a high water table and secondary soil salinization are dominant conditions in eastern Isfahan Province, Iran. This region has a low annual rainfall, high annual evaporation demand, saline soils and limited fresh water supplies. To investigate the effects of irrigation deficit and salinity on cantaloupe (Cucumis melo L. var. cantalupensis) production, a field experiment was performed at the Salinity and Drainage Research Station of Rudasht, 65 km East of Isfahan. Irrigation treatments were T65, T80 and T95 (irrigation after 65, 80 and 95 percent of cumulative evaporation from Class A pan, respectively), each having three replicates. EC of irrigation water was 5.25 dS m-1; irrigation water depth for the whole growing period was 300, 342 and 384 mm, for T65, T80 and T95 treatments, respectively. The results showed that T65 and T80 irrigation treatments significantly reduced fresh yield, number of fruit, fruit weight per plant and water use efficiency. Fresh-fruit yield was 31.73, 38.48 and 54.34 ton ha-1, and water use efficiency was 10.58, 11.25 and 14.16 kg m-3 in T65, T80 and T95 irrigation treatments, respectively. A second order polynomial equation was fitted (R2= 0.99) for production function (yield vs. irrigation water depth). The relationship between water use efficiency and irrigation water depth was also a second order polynomial equation (R2= 0.97). Nitrogen and potassium content of fruits in T65 treatment was higher than T80 and T95 treatments. Effect of irrigation regimes was not significant on P and Na content of fruits, but was significant on Cl- content (P< 0.05). Overall results showed that cantaloupe is a crop sensitive to soil moisture stress.}, Keywords = {Muskmelon,Production function,Trickle irrigation}, volume = {11}, Number = {4}, pages = {469-479}, publisher = {Tarbiat Modares University}, url = {http://jast.modares.ac.ir/article-23-6698-en.html}, eprint = {http://jast.modares.ac.ir/article-23-6698-en.pdf}, journal = {Journal of Agricultural Science and Technology}, issn = {1680-7073}, eissn = {2345-3737}, year = {2009} } @article{ author = {Valizadeh, M. and KazemiTabar, S. K.}, title = {Investigation of Plant Growth Regulators Effects on Callus Induction and Shoot Regeneration of Bunium persicum (Boiss.) B. Fedtsch.}, abstract ={Parsi Zira, Bunium persicum (Boiss.) B. Fedtsch., or Black Zira, a member of the Umbellifera family, is one of the most important medicinal species with high economic value. Generally, there is limited information about in vitro culture of Bunium persicum. In this study, the effect of various media (MS, B5) and combinations of plant growth regulators, NAA and 2,4-D alone or together with Kin, on callus induction and shoot regeneration from hypocotyl explant were investigated. This experiment has been carried out in a completely randomized design with 30 treatments and 10 replications per treatment. The results showed significant effects of treatments on regeneration and callus induction. All the measured traits for MS medium were superior. The highest callus frequency was observed on the medium containing 0.1 mg L-1 or 1 mg L-1 2,4-dichlorophenoxyacetic acid (2,4-D) as well as 2 mg L-1 2,4-D and 0.5 mg L-1 kinetin. The best treatment for somatic embryogenesis was the medium containing 2 mg L-1 2,4-D. The best response for shoot regeneration was observed on the medium supplemented with 1 mg L-1 2,4-D. The medium containing 1 mg L-1 2,4-D was the best for callus induction and shoot regeneration simultaneously. The regenerated shoots were rooted on basal medium.}, Keywords = {Bunium persicum (Boiss.) B. Fedtsch,Hypocotyls explants,Shoot regeneration,Tissue culture}, volume = {11}, Number = {4}, pages = {481-486}, publisher = {Tarbiat Modares University}, url = {http://jast.modares.ac.ir/article-23-11957-en.html}, eprint = {http://jast.modares.ac.ir/article-23-11957-en.pdf}, journal = {Journal of Agricultural Science and Technology}, issn = {1680-7073}, eissn = {2345-3737}, year = {2009} } @article{ author = {Mohammadi, S. and Kalbasi, M. and Shariatmadari, H.}, title = {Cumulative and Residual Effects of Organic Fertilizer Application on Selected Soil Properties, Water Soluble P, Olsen-p and P Sorption Index}, abstract ={Long-term application of fertilizers containing P, especially organic fertilizers, usually increases the water soluble and available P of soil and at the same time may result in P accumulation in soil. Organic fertilizers may also increase movement of P in the soil profile that could result in surface and ground water pollution. An experiment was conducted on field plots that received three applications (25, 50 and 100 Mg ha-1) of solid dairy manure, sewage sludge, or urban solid waste compost, and one application of chemical fertilizers (250 kg ha-1 urea plus 250 kg ha-1 mono-ammonium phosphate) for 1, 2, 3, 4 or 5 consecutive years in order to investigate the residual and cumulative effects of organic and chemical fertilizers on selected soil properties, water soluble and bioavailable P as well as the P sorption index of the soil. Average organic matter content in the soil increased as a result of organic fertilizer applications. The increase was proportional to the rate of application and was highest for dairy manure and lowest for urban solid compost. Both the water extractable and bioavailable P contents of soil increased with the rate of application, the nature of organic fertilizer and the number (years) of applications, with the rate being the most effective and the nature of fertilizer the least effective. Dairy manure had the largest and solid waste compost the smallest positive impact on both the water soluble and available P content of soil. Effect of sewage sludge application on available P content of the soil was greater than its effect on the water extractable P. The phosphorus sorption index was independent of the source of P (organic or chemical), the nature and the rate of organic fertilizers and was only significantly dependent on the number (years) of fertilizer applications.}, Keywords = {Bioavailable P,Cumulative effect,Organic fertilizers,Soluble P,Sorption index}, volume = {11}, Number = {4}, pages = {487-497}, publisher = {Tarbiat Modares University}, url = {http://jast.modares.ac.ir/article-23-5588-en.html}, eprint = {http://jast.modares.ac.ir/article-23-5588-en.pdf}, journal = {Journal of Agricultural Science and Technology}, issn = {1680-7073}, eissn = {2345-3737}, year = {2009} }