نشریه علوم آب و خاک (علوم و فنون کشاورزی و منابع طبیعی)
سال یازدهم شماره 1 (پیاپی 39، بهار 1386)

Cultivation of a second crop in paddy fields of Guilan province is a strategy for optimum use of land, supporting family economy and increasing oil-seed production. However, this is impeded under high rainfall and waterlogging conditions. To enhance second-crop cultivation in paddy fields, surface drainage is inevitable. The surface drainage practices should be performed with minimum costs, least time span and least variations of the land. In the present research, longitudinal surface drains were constructed with a spacing of 2, 4, 6, 8 and 10 m (depth of 20 cm), with and without 1-m lateral drains (depth of 10 cm) in Rice Research Institute, Rasht, Iran. The experiment was conducted in a complete randomized block design with three replications. Canola (Brassica napa), variety PF, was cultivated as a second crop after rice. The results showed that the effects of drain spacing on seed yield, days to maturity, number of plants per m2, and also the effects of lateral drainage on seed yield, plant height, residual N, days to maturity, and number of plants per m2 are significant (P<0.01). Highest yield (2493 kg/ha) was obtained from longitudinal drains 4 m apart, with lateral drainage drain spacing of 6 and 2 m had acceptable yields, too (2241 and 1817 kg/ha, respectively). For treatments without lateral drainage, 2-m drain spacing had the highest yield (1324 kg/ha). Considering all the expenses for drainage construction, it was found that net benefit of longitudinal drain spacing of 4 and 6 m was twice the costs. Since the rainfall in Nov., Dec., and Jan., 2000, was higher than the 20-year average rainfall of the same months, it was concluded that the results of this experiment may be recommended in the years with a rainfall less than the year 2000.

One of the simple methods for erosion control, flood mitigation and flood damage reduction in the streams is building the checkdams. The present study was carried out to evaluate the performance of checkdams, location across the streams in the retention of the fine sediments in Droudzan watershed in Southern Iran. For this purpose, a number of streams with many stabilized check dams which were more than 27 years old were selected. For each stream, three check dams (one at the far beginning (upstream), the second one at the middle and the third one at the far downstream) were selected. In each stream, a number of samples were taken from retained sediment behind the selected check dams and also original soil was taken from both sides of the same check dams. Laboratory analysis on the size of particles and also texture of soil and sediment samples showed that in general, soils taken from both sides of the check dams were finer than sediment behind the same check dams. Comparison of particle sizes showed in all streams except Joobkhaleh (with extensive tree coverage) the performance of the third check dams (far downstream) in fine sediment retention is much better than the second one (at the middle) and the second one is more effective than the first one (upstream). Comparison of sands, silt, and clay percentage of soil and sediment also showed that in all streams except Joobkhaleh the clay and silt percentage behind the third check dam is more than the second check dam and that of the second check dam is more than the third one (upstream). In the same way, results showed that the sand retained behind the first check dam, was more than the sand behind the second and first checkdams, respectively. Therefore, if the retention of the fine sediments is the main purpose of the check dam construction, it is recommended that they be built in the far downstream rather than in the upstream of waterways.

The model in this research was created based on the Artificial Neural Network (ANN) and calibrated in the Sefid-rood dam basin (excluding Khazar zone). This research was done by gathering and selecting peak flows of hydrographs from 12 sub basins, the concentration time of which was equal to or less than 24 hours and was caused only by rainfall. From all the selected sub basins, totally 661 hydrographs were prepared and their peak flows data wes used to make prediction model. The input variables of the model consisted of the depth of daily flooding rainfalls, and so the five days before rainfall of every peak flow, the area of sub basins, the main stream length, the slope of 10-85 percent of main stream, the median height of sub basins, the area of geological formations and rock units, classified at three hydrological groups of I, II, III, the base flow, and output variable was only peak flow. By using Feed Forward Artificial Neural Network with training method of back propagation error the function approximation of inputs to output was created by passing the three processes of training (learning), testing and validation. So based on that data and variables, the Multivariable Linear Regression model was created. The comparison of observed peak flows, based on validation data package, showed that the statistical parameters of (R2) coefficient and Fisher’s test parameter coefficient (F) for ANN model and MLR respectively were 0.84, 33.66 and 0.33, 3.60, indicating the superiority of ANN to traditional methods.

Application of sewage sludge on the farmland as a source of crop nutrient had recently received considerable attention. Some management practices may be required to control the accumulation of toxic elements including Pb, Ni and Cd. Sequential extraction gives useful information on plant bioavailability of the elements. The objective of this study was to investigate the cumulative and residual effects of sewage sludge application on the chemical forms and mobility factor of Pb, Ni and Cd. Zero, 25, 50 and 100 Mg ha-1 of sewage sludge were applied for 1, 2 and 3 consecutive years in a split plot design, with three replications. Soil samples were taken from 0-20 cm at the end of the third year of application. Different chemical forms of Pb, Ni and Cd were measured. Results revealed that the soluble form (SOL) of Ni and Cd increased whereas Pb soluble form decreased with increasing levels and years of application. Exchangeable (EXC), carbonate (CAR) and organic (ORG) forms of the three elements increased as levels and years of application increased. Occluded (OCC) form decreased for Pb, Ni and increased for Cd. Residual form (RES) of Pb increased while that of Ni and Cd decreased. A gereral increase was observed for available (DTPA-extractable) concentration of Pb, Ni and Cd. Relative distributions of different chemical forms were in the following order: Pb: OCC > RES> ORG> CAR> EXC> SOL, Ni: RES> ORG> OCC> CAR>EXC> SOL and Cd: OCC> CAR> RES> ORG> EXC> SOL. The comparison of different forms of the metals showed the following orders: soluble Ni>Pb>Cd, exchangeable, carbonate and occluded Pb>Ni> Cd, organic and residual Ni> Pb>cd. Increasing the available (DTPA-extractable) concentration of the elements in such a calcareous soil showed that consecutive application of sewage sludge may increase the available (DTPA-extractable) concentration beyond critical levels. A significant corretation was observed between organic form and available (DTPA-extractable) concentration of the elements.

Accumulation of heavy metals (HMs) in cultivated soils is an important environmental problem in many parts of the world. In recent years, HM leaching through preferential paths and also in the form of metal-organic acids complexes has received much attention. For this reason, the effects of plants on creating preferential flow through the soil is important. The objective of this study was to assess the mobility of Cd, Cu, Pb and Zn in a calcareous soil (Typic Haplocalcids) planted with safflower (Carthamus tinctorious). The study was conducted on 12 undisturbed soil columns (22.5 cm in diameter and 50 cm in depth) in greenhouse. The top 10 cm of soil in half of the columns were contaminated with Cd, Cu, Pb, and Zn at the rates of 19.5, 750, 150 and 1400 kg ha-1, respectively. Half of the contaminated and uncontaminated columns were planted with safflower at a rate of 20 seeds m-2. Leachate was collected continuously and analyzed for these four heavy metals. After the crop harvest, soil samples were taken at 10 cm intervals and analyzed for DTPA-extractable and water-soluble HMs concentration. Results showed that heavy metal concentrations (DTPA and soluble) of the subsoil in planted columns were more than in fallow columns. The DTPA-extractable Cd, Cu and Zn concentrations in contaminated planted columns were 3.3-, 1.5- and 1.5-times more than in contaminated fallow columns, respectively. The water-soluble Cd, Cu and Zn in planted treatments increased 2.4, 1.2- and 1.1 times more than the fallow treatment. Lead concentrations in both planted and fallow treatments were similar. Metal uptake by safflower increased such that Cd and Zn uptake was more than Cu and Pb. Cd, Cu, Pb and Zn concentrations in the leachate of planted columns increased 32.0-, 2.5-, 6.0- and 2.7- time more than the uncontaminated planted columns. In summary, although topsoil contamination increased metal uptake by safflower, however the presence of safflower increased DTPA-extractable and also soluble metal concentrations in the soil profile and therefore enhanced metal mobility. The order of metal mobility was Cd > Zn >Cu >Pb.

This study was conducted to evaluate the effect of salinity on concentration of potassium (K), sodium (Na) and chloride (Cl) ions, in sweet lime budded on five citrus rootstocks, including Bakraii (mandarin x sweet lime), Volcameriana, Sour orange, Sweet lime and Mexican lime in a glasshouse, using a randomized completely design with factorial arrangement and four replications. Rootstocks had great effect on the concentration of ions in scion. Concentration and distribution of ions were significantly different in control and other treatments. Salinity increased Na and Cl ions in shoots and roots, but the rate of increase varied among rootstocks and treatments. Lowest concentration of Na and Cl ions were in shoot of scion on Volkameriana. Under salinity stress, K concentration increased in shoots of scion on Sour orange and Bakraei and decreased it on other rootstocks. Salinity increased K concentration in roots of all rootstocks except for Mexican lime.

Sewage sludge application on farmland as fertilizer is commonly practiced in many countries. Sewage sludge is rich in macro- and micro- nutrients. However, high concentration of heavy metals in sludge may cause pollution of soil, groundwater and human food chain because of uptake of toxic metals by crops. The objective of this study was to determine residual and cumulative effects of sewage sludge on concentration of Pb and Cd in soil and wheat. Different levels of 0, 25, 50 and 100 Mg ha-1 of sewage sludge were applied to the soil for four years. To study the cumulative and residual effects of the sewage sludge, applications were repeated on three fourth of each plot in the second year, on one half of plots in the third year and in one fourth of plots in the fourth year. Wheat grown in the plots, after the fourth year, soil samples from the 0-20 cm depth of the different parts of the plots were taken and analyzed. Wheat was also harvested roots, stems and grains were separately analyzed for the heavy metal concentritons. Cumulative sewage sludge application increased OM, CEC, ECe, total and DTPA-extractable concentration of Pb and Cd in soil significantly (P≤ 0.05). Residual sewage sludge in the soil also increased CEC, total and DTPA-extractable concentration of Pb and Cd significantly. Single sludge applications at different rates increased the DTPA-extractable concentrations of heavy metals. In subsequent years with no further sludge application, DTPA–extractable metal concentrations in soil decreased continuously approaching the levels in the control. However, even after four years, DTPA-extractable concentration of Pb and Cd, were still significantly higher in plots which received more than 50 Mg ha-1 sludge than control. DTPA-extractable concentrations of Pb was closely correlated with total concentrations. Sewage sludge increased concentration of Cd in roots and stems and Pb in grains significantly. Cumulative effects on concentrations of Pb in grains, and Cd in stems were more than residual effects. The results of this study show that cumulative and residual effects of sewage sludge application increased concentrations of heavy metals in soil and wheat.

Cadmium (Cd) and its rate in soil have received lots of attention because it is easily taken up by plant root, making it 20 times more toxic in comparison with other heavy metals. Knowledge about the factors affecting Cd availability and conversion of its chemical forms is, therefore, important. Sequential extraction has been used as a suitable method for identification of chemical forms and their relationship with plant availability, but in soils of Iran less attention has been paid to studying the change in chemical forms as affected by time. The present research was designed to study the change in Cd chemical forms as affected by application rate and time of incubation in two soil textural classes. A clay loam calcareous soil [Fine, mixed (calcareous), mesic Typic Calcixerepts] was converted to sandy loam soil by adding pure quartz sand and both soils were treated with 0, 5, 15, 30, and 60 mg Cd / kg soil as cadmium sulfate and incubated at room temperature near field capacity moisture. After 0, 1, 2, 4, 8, and 16 weeks, chemical forms of Cd were determined by sequential extraction. Results showed that, depending on the textural classes, about 82 and 87 % of applied Cd was converted to soluble+exchangeable, carbonate, and organic forms. In both soils carbonate fraction was dominant. Conversion of applied Cd to soluble+exchangeable and carbonate forms in sandy loam was higher than in clay loam. For organic, manganese oxide, amorphous iron oxide, and residual forms, the reverse was true. The crystalline iron oxide form was less than detection limit of atomic absorption in both textural classes. Increasing the application rate caused an increase in all forms of Cd but the percentage increase depended on the capacity of different soil components for Cd retention. Carbonate showed the highest capacity for retention. The effect of incubation time on conversion of Cd to different forms was significant. However, in almost all treatments more than 80 % of added Cd was converted to carbonate and organic forms immediately, and the proportion approximately stayed the same throughout the course of experiment.

Estimation of unsaturated soil hydraulic and solute transport properties by Inverse modeling has thus far been limited mostly to analyses of one-dimensional experiments in the laboratory, often assuming steady-state conditions. This is partly because of the high cost and difficulties in accurately measuring and collecting adequate field-scale data sets, and partly because of difficulties in describing spatial and temporal variability in the soil hydraulic properties. In this study we estimated soil hydraulic and solute transport parameters from several two-dimensional furrow irrigation experiments under transient conditions. Three blocked-end furrow irrigation experiments were carried out, each of the same duration but with different amounts of infiltrating water and solutes resulting from water depths of 6, 10, and 14 cm in the furrows. Two more experiments were carried out with the same amounts of applied water and solute, and hence for different durations, on furrows with water depths of 6 and 10 cm. The saturated hydraulic conductivity (Ks) and solute transport parameters in the physical equilibrium convection-dispersion (CDE) and physical nonequilibrium mobile/ immobile (MIM) transport models were inversely estimated using the Levenberg-Marquardt optimization algorithm in combination with the HYDRUS-2D numerical code. Estimated Ks-values ranged from 0.0389 to 0.0996 cm min-1, with a coefficient of variation of 48%. Estimated immobile water contents (θim) were more or less constant at a relatively low average value of 0.025 cm3 cm-3, whereas the first-order exchange coefficient (ω) varied between 0.10 and 19.52 min-1. The longitudinal dispersivity (DL) ranged from 2.6 to 32.8 cm, and the transverse dispersivity (DT) from 0.03 to 2.20 cm. DL showed some dependency on water level and irrigation/solute application time in the furrows, but no obvious effect was found on Ks and other transport parameters. Agreement between measured and predicted infiltration rates was satisfactory, whereas soil water contents were somewhat overestimated and solute concentrations underestimated. Differences between predicted solute distributions obtained with the CDE and MIM transport models were relatively small. This finding and the value of optimized parameters indicate that observed data were sufficiently well described using the simpler CDE model, and that immobile water did not play a major role in the transport process.

In order to investigate mineral manganese forms and their relations with plant responses, 22 soil samples from Fars province (0-20 cm) were in a greenhouse experiment filled in 3 liter pots, and soybean (Glycine max (L.) merr.,CV.Williams) was grown for 7 weeks. Chemical forms of manganese were determined in soils by warden and Reisenauer sequential extraction method (readily soluble, weakly adsorbed, carbonate bound and oxide bound extracted with Ca(No3)2, Ca DTPA +Na2B4O7, HNO3 and NH2OH. HCl, respectively) after harvesting the plants. Results showed that the amount of Mn in different forms was in the following order: Carbonatic Mn >Mn Oxides >Weakly adsorbed Mn > Soluble Mn. Regression equations between soil properties and Mn forms showed a significant correlation between calcium carbonate equivalent and carbonate bound Mn. Significant correlation between Carbonate bound Mn and concentration of Mn in the aerial part of soybean showed that this fraction plays an important role in plant nutrition.

Studies show that excessive rotation of rice, when the grains revolve inside the milling chamber, increase the breakage. Ease of grain movement in the milling chamber could minimize this problem by utilizing screw conveyor at the first part of rotor. In this study the rotor of a conventional milling was equipped with a screw conveyor. The effects of two rotor types (modified and conventional rotors), three output rates (412, 654 and 915 kg/h) and three blade distances from the agitator (11, 12 and 13mm) were examined on indices of rice quality using a split-split plot design. In this experiment, the percentage of whole white rice and breakage, degree of milling and milling performance index were either measured or calculated. Results showed that only the effect of blade distance on percentage of breakage was significant whereas the effect of feed rate on all measured parameters was significant. In addition, the interaction effects of rotor type and blade distance, rotor type and feed rate on percentage of whole white rice and breakage were significant, respectively. The milling performance index showed that the best conditions for both rotors can be obtained at output rate of 412kg/hr and 11or 12mm blade distance from the agitator. For this adjustment, the average of percentage of breakage in the modified and conventional rotors were 20.5 and 23, respectively.

For measuring draft force and drawbar power requirements for mounted implements, precise instruments such as three-point hitch dynamometers and tractor speed measurement devices are needed. In this research, a frame-type three-point hitch dynamometer was built and evaluated. Forces applied to dynamometer are measured by three separate load cells located on a frame which can be attached to tractor’s three-point hitch. Each dynamometer’s load cell measures load using a strain gauge bridge circuit. Each load cell was calibrated by applying a known load and measuring bridge circuit’s output voltage. Dynamometer was calibrated by the application of known forces and measuring the output voltage of the strain gauge bridges. The calibration showed a high degree of linearity between the applied forces and the bridge outputs (R2 = 0.996). The hysteresis effect between loading and unloading as well as the effect of the position of the applied forces from the longitudinal axis of the dynamometer was small. For measuring actual tractor speed, a fifth wheel equipped with an encoder shaft was designed and built. The calibration on tarmac and soil surfaces showed a highly linear relation between measured forward speed and output of encoder’s rotation (R2 =0.994). The errors in speed measurements at low speed in field and at high speed (up to 12.5 km/h) on tarmac surface were approximately 3 and 8%, respectively. The data acquisition system, not only could display the instantaneous force and speed, it could also show force-time and force-distance curves on the system’s monitor.

To evaluate the effects of heat treatments on sprouting weight, loss and other charactristics of two potato cultivars (Agria and Diamont) in cold (9±1) and ambient (18±1) storage, a series of experiments were conducted in 2004. In this study, after curing, the tubers of both cultivars were treated with warm air, at 25, 35, 45 and 57oC for 4, 8 and 12 h and with warm water at 22, 54 and 57 for 15 and 30 min. Treated tubers were packed in net bags and were kept in cold and ambinent storage for 2 and 4 months. The results of the study indicated that warm air at 45oC for 8 and 24 h and warm water at 57oC for 15 min. in comparison to control reduced the percentage of tuber sprouting significantly, without internal changes in tubers composition.

In vitro regeneration of four cultivars of carnation namely ‘Nelson’, ‘Impulse’, ‘Sagres’ and ‘Spitit’ through somatic embryogenesis was studied. MS culture medium was supplemented with 30 gl-1 sucrose, 2 mgl-1 2,4-D and 0.2 mgl-1 BA and used for embryogenic callus formation. Somatic embryos were formed when embryogenic callus was transferred to MS medium without growth regulators containing 30 g/l-1 sucrose alone or supplemented with different concentrations of mannitol (15, 30, 60, 90, 120 and 150 gl-1). No somatic embryo was formed on culture media containing mannitol without sucrose. Number of somatic embryos produced from embryogenic calli significantly increased by adding mannitol to the culture media. Normal embryos formed on culture media containing high concentrations of mannitol (60, 90, 120 and 150 gl-1) developed normally. About 95% of somatic embryos transferred to the1/2 MS culture medium containing 30 gl-1 sucrose, germinated into plantlets. Plantlets also continued their growth under greenhouse conditions.

This research was conducted at Rsearch Farm of Isfahan University of Technology to evaluate yield stability of 9 Oat (Avena sativa L.) genotypes and Makooi barley, to determine the contribution of each environmental factor to genotype × environment interaction, and to find the most stable yield component in these genotypes. Four Canadian cultivars and 5 Turkish breeding lines were included in this experiment. Three dates of planting (12 Oct. 31 Oct. and 21 Nov.) and three sowing rates (300, 375 and 450 seed m2) were used as 6 environments. In each environment a randomized complete blocks design with 3 replications was used. Grain yield, No. of panicle/m2, No. of seed/ panicle, and 1000-grain weight were measured. Result of combined analysis of variance showed highly significant (P < 0.01) difference among genotypes for all the studied traits. Significante differences were observed among environments for all the characteristics except for 1000-grain weight. Grain yield and its components showed highly significant genotype × environment interaction ffects. The ratio of genotype × environment interaction sum of square to total sum of square for grain yield (22.37%) was higher than other traits. Stability analysis based on regression coefficient showed that Boyer cultivar and Line No.28 with nearly b=1 and more than average yields were the most stable genotypes. Pacer cultivar and Makooi Barley had specific adaptations with suitable and unsuitable environments, respcctively. Based on deviation mean square, Boyer cultivar was the most stable one among high yielding genotypes. Tai’s path analysis of genotype × environment interaction showed that V3 genotypic component (Seed weight) was the most effective component of stability and yield. Boyer with the highest V3 score was the highest yielding and stable genotype. According to environmtntal component of path analysis, fertilization stage and grain filling period were the most sensitive growth stages to environmental conditions. Therefor, it is not effective to evaluate genotype stability according to V2 component (seed/panicle). Finally, according to the result of this experiment Boyer with grain yield of 5.8 t/ha and stable response in all environments was selected as a suitable cultivar for breeding programs or introduction for commertial production.

Generation mean analysis (GMA) was used to study the type of gene action and inheritance of grain yield and its components. Generation mean analysis with joint scaling test was performed. This research was conducted at research farm of college of Agriculture at the University of Tehran. The parents and their progenies ( F1, F2, BC1 & BC2) in three mating groups ( Sardari × 7007, Sardari × 7107& 7107 × 5593) were produced and planted using a randomized complete block design with four replications for each mating group. Of four replications in each experiment, two replications for drought and two replications for non-drought condition were used. The eight traits which were evaluated included grain yield, plant height, plant weight, tiller number, spike length, grains per spikes and 100 grain weight. Most of the genetic parameters including mean (m), additive (d), dominant (h), additive × additive [i], additive × dominant [j], and dominant × dominant[l] effects were significant. However, all gene effects were not significant in all traits.The dominant gene effect was the most contributor factor to inheritance of the majority of traits. For the majority of the traits, additive gene effect was significant, but its magnitude was less than dominant gene effect. Also the dominant × dominant[l] epistasis was more important than additive× additive [i] epistasis. The degree of dominance in most of traits indicated the predominance of dominant gene effects.

In order to examine the responses of proso millet (Panicum miliaceum) to drought stress at different growth stages, four breeded genotypes and a local one of proso millet were selected and planted in a split-plot design with five irrigation treatments and three replications.This experiment was conducted in two locations, Birjand and Sarbisheh. Irrigation treatments included well - watered, drought stress at vegetative stage, ear emergence stage, seed filling stage and vegetative and seed filling stages which were considered as main- plots. The first five mentioned genotypes were considered as sub-plots. Drought stress. caused a great reduction in grain yield and WUE at ear emergence stage. This reduction represented itself in the number of seed per ear and the weight of seeds, but it didn’t have any effects on the number of ear. At ear emergence stage, the drought stress increased the floret death and loss of weight of seeds which resulted in the reduction in the harvest index of both ear per plant and seed per plant. Comparison of genotypes indicated that since K-C-M.4 had a greater number of ears and K-C-M.9 had heavier seeds that had higher grain yield. These two genotypes had the highest WUE and their harvest indices were relatively higher. Due to the salinity of water and infertility of soil in Birjand, the grain yield was lower compared with Sarbisheh. In summary, it can be said that genotype K-C-M.4 proved to be more suitable for both areas.

Half diallel crosses of eight bread wheat cultivars were used to estimate the genetic parameters and types of genetic control for yield and yield components, and to determine the effects of environmental factors on these parameters. Parents and their F2 hybrids were grown in a randomized block design under irrigated and stressed (terminal drought) conditions. For all traits, except for number of spikelets per spike and number of grain per spike, the effect of environment (irrigated v.s stressed) and genotype by environment interaction were significant. The mean square of GCA for all characters was significant in both environments, except for number of fertile tillers in the irrigated condition and grain yield in the stressed conditions. The mean square of SCA was significant for plant height only in the irrigated condition, while for number of fertile tillers and grain yield it was significant in both conditions. The high significant ratios of GCA to SCA mean square indicated the importance of additive genetic effects on controlling plant height, spike length number of grain per spike in both environments and number of spikelets per spike in the stressed condition. The parameter estimation revealed partial dominance gene actions for plant height, spike length and grain per spike in both environments, and number of spikelets per spike in stressed environment, whereas over-dominance gene actions were observed for the other traits in one or both conditions.

A karyotypic study was performed on seven species of Hordeum Genus including, H. vulgare, H. spontaneum, H. glaucum, H. distichon, H. geniculatum , H. bulbosum and H. violaceum. According to the cytological studies in the laboratory, chromosome numbers and ploidy levels of species were identified. Chromosome analysese including the length of each chromosome, long and short arms length and long - short arm ratio were also done. For each species, the karyotype as an ideogram was drawn. The results showed that H. geniculatum, H. bulbosum, and H. violaceum were tetraploid (2n=4x=28) and the other species were diploid (2n=2x=14). Chromosomal study of H. geniculatum and H. distichon is reported for the first time from Iran. Karyotypic formula showed that the diploid species were 7m and tetraploid were 12m +2sm. According to the karyotypic symmetry, all species were in the 1A class. Using the S%, TF%, D.R.L., T.V. and X parameters, karyotypic symmetry of species was analyzed and determined.

In order to study the physiological responses of two barley cultivars to salinity stress, a 4-replicate CRD greenhouse experiment was conducted during at the College of Agriculture, Shiraz University, Iran2003-2004. The treatments consisted of two barley cultivars: Afzal and Reyhan and five salinity levels: 0, 4, 8, 12 and 14 dS/m. Seedling emergence, number of tillers and leaves per plant, leaf area and dry matter decreased with increasing salinity levels. The reductions were lower in Afzal (salt tolerant) than Reyhan (salt sensitive). A lower Na+ and higher K+Na+ in Afzal compared to Reyhan were observed under high level of salinity. The results of the present experiment also showed that the tolerance to salinity was associated with a greater stomatal conductivity, as well as transpiration and photosynthesis rate. Sub-stomatal CO2 concentration in both cultivars decreased with an increase in salinity, with the exception of 12dS/m, where it led to an increase in sub-stomatal CO2 concentration. Leaf temperature increased with an increase in salinity level in both cultivars, whereas a more pronounced decrease for number of fertile tillers, ears per plant, kernels per ear, thousand grain weight and harvest index was observed in Reyhan compared to Afzal .Since a higher tolerance to salinity in Afzal was apparently associated with a lower concentration of Na+ and a higher K+/Na+ ratio of the shoots, this trait could probably be used for yield improvement of barley cultivars under saline conditions.

This research was conducted at Research Farm of Isfahan University of Technology to examine the relations among phonologic, morphologic and physiologic traits and their effects on grain yield of 20 oat (Avena sativa L.) genotypes. A randomized complete block design with three replications was used in each irrigation treatment (i.e. irrigation after 70±3, and 130±3 mm evaporation from class A pan). Grain yield had significant and positive correlations with harvest index and relative water content (RWC) in both irrigation treatments and with plant height at maturity in non-stress condition. Also, grain yield had significant and negative correlation with days to heading. Factor analyses resulted in three factors in each condition, which were named yield factor, phenologic factor and sink factor in both conditions. Based on stepwise regression, harvest index was the first character which entered the grain yield model in both conditions. At the next step, RWC and plant height entered the model, with harvest index explaining 66% and 64% of yield variation in stress and non-stress conditions, respectively. The results of path analysis in both conditions showed that harvest index had the highest positive direct effect on grain yield. The highest indirect negative effects through number of grain per panicle were obtained for the harvest index and panicle m-2 in stress and non-stress conditions, respectively.

Zn deficiency is one of the most important nutritional disorders after macro-nutrients in rice. There are considerable genotypic differences among rice genotypes in response to Zn deficiency. Determination of such differences and introduction of efficient genotypes could lead to significant reduction of fertilizer use for rice production. In this research, some of the most frequently cultivated rice genotypes in Northern Iran, were compared for their tolerance to Zn deficiency in a field (11 cultivars) and hydroponic (16 cultivars) experiment. Four levels of Zn fertilizer were used in field experiment including 0 (control), 25, 50 and 100 kg ha-1 and three different activity of Zn in chelator-buffer experiment including 130 (control), 23 and 5 pM. Experiments were conducted using complete randomized block design and data was analyzed using two factorial analysis of variance including Zn level and genotypes. In addition to yield components in the field study and dry matter production in the hydroponic culture medium, concentration of Zn was also determined in shoot, root and seed. The comparison of all yield components showed that the cultivar Onda was the most Zn-inefficient (susceptible to Zn deficiency) and Khazar was the most Zn-efficient (tolerant to Zn deficiency) genotypes under field conditions. In hydroponic experiment, cultivars Fajr, Tarom Hashemi and Onda were determined as the most Zn-inefficient and Shafagh, Amol and Mianeh were recognized as the most Zn-efficient genotypes. The most significant response to Zn fertilizer, in terms of Zn accumulation in seeds, was observed in Nemat and Tarom Deilamani. In contrast, Cadoos accumulated Zn mostly in straw. Results of our experiments introduced not only the genotypes with the highest yield on soils low in available Zn, but also genotypes with the highest Zn accumulation in seeds in response to Zn fertilizers which are important for human nutrition.

Drought stress is one of the major limiting factors of crop yield. A field experiment was conducted to study the effects of drought stress on yield and yield components of nine bread wheat and one durum wheat genotypes during 2003-2004 growing season. The experiment was designed as two separate randomized complete blocks design with three replicates under well-watered and unwatered conditions during the post-anthesis period. Post-anthesis drought stress reduced the grain yield and yield components in all genotypes. Mean of each trait significantly(p≤%5) decreased under drought stress conditions, except for spikeletes number per spike and ear number per square meter. The highest yield loss was caused by the grain number per ear and 1000- grain weight reduction under drought stress conditions.“Gahar” genotype had the highest grain yield (4149 kg/ha) under drought stress conditions, whereas the highest grain yield (6674 kg/ha) was obtained for “Nikenejad” genotype under optimum conditions. Based on stress susceptibility index, “Koohdasht” and “Boholh-15” genotypes showed the lowest and the highest yield loss in response to drought stress, respectively. Correlation analysis of yield and yield components indicated that, under drought stress conditions, ear number per square meter (r=0.751) and biological yield (r=0.707) had the highest correlation with the grain yield(p≤%5), whereas these traits were grains number per ear(r=0.864) and biological yield (r=0.848) for the well-watered conditions. Therefore, it might be possible to select genotypes for greater grain yield with the means of the traits which have the highest correlation coeficient with the grain yield under each moisture regime. Generally, it appeared that “Gahar”and “Nikenejad” genotypes with greater yield potential might be recommended for agronomic conditions similar to the present investigation.

A total of 25 advanced rapeseed (Brassica napus L.) varieties were evaluated under cold weather conditions using Randomized Complete Block design (RCBD) with four replications in Dr. Nakhjavani Agricultural Research Station, 35 km North-East of Urmia the capital of West Azerbaijan province in 2000-2001. The results showed significant differences among the varieties (P ≥ 0.01) for all the phenological stages including days to germination, days to rosette completion, days to initiation of stem elongation, days to flowering initiation, pod formation stage and days to maturity. The spring varieties Sarigol (PF7045/91), Hyola 42 and SYN1 and autumnal varieties Alice, Eurol, Fornax, VDH 8003-98, Consul, Licord and Zarfam (Regent× Cobra), showed early maturity. On the other hand, Mohican, Olara, Colvert, L-1 and Akamar were late mature varieties. In fact, the most prolific varieties, DP.94.8, Zarfam (Regent ×Cobra) Cocktail, Consul and SLM046 (control variety) had the highest ability survive in the cold conditions and they completed their rosette stage sooner than the other varieties. There was positive and significant correlation between duration of pod formation stage and seed yield. Maturity date of varieties was positively and significantly correlated with harvest index, number of seed per pod, days to germination, days to rosette completion, days to stem elongation, days to flowering, and days to pod formation. Negative and significant correlations were found between days to maturity and duration of flowering and pod formation stages. It can be concluded that delay in initiation or completion of each growth stages could delay maturity of the rapeseed varieties.

Seed traits are an important measure of the effects of endophytic fungi in Festuca genus. In this study, endophyte-infected (E+) and un-infected (E-) clones of the same tall fescue genotypes were used to investigate the effects of endophyte on the seed production and associated traits. Endophyte infection resulted in 32.8% increase of total seeds by weight, 34.6% seeds per plant, and 30.6% panicles per plant, but other seed components were not affected by endophyte. Significant phenotypic variances were observed for traits except for 1000 seed weight. Plant genotype×fungal status interactions occurred for seed per plant. These interactions occurred largely because of variation in different plant genotypes. Genetic variance for this trait in E+ was greater than E- for both years, suggesting that the endophyte can mask plant genotypic variance. The results indicated that endophyte had a positive effect on seed production but could result in overestimating of plant genetic variance for some traits. In conclusion, breeding strategies should consider presence or absence of endophyte and the possible effects on variances.

Sunflower (Helianthus annuus L.) can have an important role in vegetable oil production. Also, appropriate soil fertility is necessary to obtaine higher seed yield and quality of the crop. This experiment was conducted to investigate the effect of fertilizer treatments of macro and micronutrients on seed yield and other agronomic traits in sunflower. The effects of thirteen fertilizer treatemts (as main factor) were investigated on agronomoic traits of two hybrid cultivars, "HiSun33" and "Euroflor" (as sub factor) in a randomized complete block design with three replications. The results showed that there was significant interaction between fertilizer treatments and cultivars for most of the traits and the effects of fertilizer treatments were dependent on the cultivar. Almost all of the fertilizer treatments of N, P, K, Fe, Zn and Mn either significantly or non-significantly decreased the means of head diameter, 1000-seed weight, seed yield/plant, seed yield and oil yield in Euroflor cultivar however, in HiSun33 cultivar, each of N, P, and K fertilizers had no significant effect on seed yield. Application of Zn and Mn fertilizer in soil or spraying them on plants had no significant effect on seed yield and yield components in HiSun33 cultivar however, application of Fe feritilizer (Sequestrene) significantly increased the seed yield of this cultivar and had no significant effect on its seed oil. In HiSun33, seed yield and oil content for treatments of control, NPK and NPK+Fe were 4946, 5155 and 7090 kg/ha and 40.72, 43.10 and 43.07 %, respectively. The effects of fertilizer treatments on oil concentration of seed were not significant, thus the variation of oil yield was due to the seed yield. The correlation coefficients and regression analysis showed that seed weight and head diameter were most important seed yield components,. In general, it seems that in a soil conditions like that of this experiment, Fe fertilizer can increase seed and oil yield in HiSun33 cultivar.

Isolating and cloning of plant protease inhibitor (PIs) genes and transforming them to the genome of other plants have paved the way for producing resistant transgenic plants against pests. Knowing that cystatins act as inhibitor factor against cysteine protease, short and long cystatin genes were isolated from maize mRNA. By using specific primers, cDNA of these genes were constructed and cloned in pUC19 and pGEX 2T plasmid vectors. The recombinant plasmid vectors were then transformed to E. coli (strain DH5 α) competent cells using electroporation. The competent cells harboring the clones were grown in suitable medium and cystatin proteins fused to Glutation-S-transferase (GST) were purified by glutation agarose bead filter. In each step of the procedure the presence of cystatin genes were confirmed through electrophoresis. Further evaluation proved the inhibitory effect and a mild stability of at least one of the corn cystatin (CC II) when incubated with cysteine protease.

Genetic male sterility is controlled by one pair of ressesive allele (aa) in sugar beet. This trait is used in most breeding programes. The exsistance of the character in a line or population facilitates transfer of important trait to the breeding material (for example resistance to plant disease). Also, it is possible to increase genetic diversity of monogerm populations by using genetic male sterility. The time and cost of transferring of this gene will be decreased, if the character is tagged with a molecular marker. Bulked segregant analysis using 302 RAPD primers in two F2 populations (231 and 261 population) was performed for the the identification of RAPD markers linked to the genetic male sterility gene. DNA preparation from 8 male fertile and male sterile plants were separately mixed. At first, the primers were tested on bulks. The primers with polymorphic bands were tested on individual plants of the bulks. Only if the polymorphism of the primers was confirmed, they were tested on the other individual plants. Finally, 10 and 6 markers were identified in 231 and 261 populations, respectively, which their distances to male sterility gene were lower than 50 cM. AB-8-18-600r marker was the nearest marker to male sterility gene. This marker showed only 3 and 1 recombination in 231 and 261 populations, respectively. The distance of this marker and genetic male sterility locus was estimated as 5.3 cM in combined F2 populations.

Cucumber cultivars, grown in greenhouse in the Jiroft region, were surveyed for the relative incidence of Zucchini yellow mosaic virus (ZYMV), Watermelon mosaic virus-2 (WMV-2), Cucumber mosaic virus (CMV) and Tomato spotted wilt virus (TSWV) from 2001 to 2004. Samples from 1294 plants representing different cultivars were analysed by Enzyme-linked immunosorbent assay (ELISA) and Dot immunobinding assay (DIBA). The data showed that green-house cucumbers are infected by CMV, ZYMV, TSWV and WMV-2. However, ZYMV was the most prevalent virus. Mixed infection including double and triple infection was identified in some samples. Transmission of aphid-borne viruses (CMV, ZYMV and WMV-2) by Aphis gossypii, A. fabae, A. craccivora and Myzus persicae revealed that ZYMV is most efficiently vectored by these aphids and, A. craccivora transmitted these viruses with more than 60% efficiency. In addition, WMV-2 was not transmitted by A. gossypii. In RT-PCR, ZYMV infection was confirmed by amplifying a PCR product of the predicated size 458 bp, using total RNA extracted from infected plants. All ZYMV infected samples reacted with monoclonal antibodies (705-1, 705-2 and 705-4) in TAS-ELISA test. These results showed that ZYMV isolate collected from Jiroft belongs to group A, cluster 1 or 2. In electron microscopy study, normal length of ZYMV flexuous particles in partial purified preparation was calculated as 790 nm. The molecular weight of coat protein of ZYMV was estimated at 36 KDa., using SDS-PAGE and western blotting. This is the first report of these viruses in greenhouse grown cucumber in the Jiroft region.

Gelatin as a proteineous component is important in the food, pharmaceutical, medical abd technical industeries. Gelatin is used in food industerials to prepare marmallads, jellies, confectioneries and ice cream. The main purpose of this research was to optimize the usage of cheap primary material, i.e. a lot of fishery wastes for extraction of gelatin and to decrease the importation gelatin from abroad that is usually prepared from pig skin and wastes of animal. This research was conducted in two stages. In the first stage, the effect of pH conditions( in alkaline and acidic conditions) and type of raw material (three raw material: fillet plant wastes, fish shark fish hoof) were evaluated on some best qualitative and quantitative Characteristics of gelatin( yield, purification value, color and odor and flavor). In second stage, the temperature effect( in 3 levels,70,75,80 degree of centigrade) and pH in 2 levels (6.5 and 6) were evaluated on the gelatin yield content. It should be mentioned that all of raw material were prepared from fishery factory of Booshehr. The results from first stage showed that using from alkaline condition and fishery wastes, the amount of gelatin will be maximum with pH=6.5, temperature=70 degree of centigrade. Also under the same conditions the best quality gelatin can be obtained.

To determine the preheating effect on frozen French - fries quality, four potato cultivars: Agria, Marfona, Auozonia & Auola were selected from Faridan region in Isfahan province & transferred to cold storage at temp.=5+0.5°C and RH=85-90%. At first, some physico – chemical characteristics of potato tubers such as specific gravity and dry matter content were measured by A.O.A.C methods. Also reducing sugar contents were analyzed by “High Performance Liquid Chromatography” (HPLC). The potato strips were blanched in hot water at different condition: 70°C - 4 min, 70 °C 10 min, 95 °C - 2min and then deep - fat fried at temperature 175°C for 2 minutes. Product quality properties such as texture, color and oil absorption were determined by standard methods. The data were analyzed using a factorial experiment in a completely randomized design, and average comparisons were made by by Duncan's multiple range test (p < 0.01). The results showed that blanching at 70 °C for 10 minutes markedly improved the quality parameters. Treatment at 95 °C – 2 min did not have any significant effect on Hunter Lab color parameters compared with 70 °C – 10 min. treatment, but the texture was significantly different. The oil absorption increased in strips blanched at 95 °C for 2 minutes. The samples blanched at 70 °C – 4 min had no significant effect on the product quality. In conculsion, Agria &Auola cultivars were more suitable for manufacturing French - fries than the other two varieties.

A total of 25,471 Iranian Holstein heifers distributed in 523 herds of 20 provinces were used to estimate heritability, genetic and phenotypic associations between a number of traits related to the production and reproduction performance. The Animal Breeding Centre of Iran collected the records studied in this research between 1991 and 2001. The traits associated with production were 305-day, 2x adjusted milk, fat yields and fat percentage and the traits associated with reproduction were age at first calving, number of services per conception, gestation period, calving interval as well as dry days as a separate trait. The heritability estimates were 0.31, 0.23, 0.31, 0.14, 0.03, 0.05, 0.10 and 0.01 for 305-day, 2x milk, fat yields, fat percentage, age at first calving, dry days, calving interval, gestation period and the number of services per conception, respectively. Milk yield was genetically correlated with age at the first calving (-0.14), dry days (-0.31), calving interval (0.54), gestation period (0.01) and the number of insemination per conception (0.38). Fat yield had negative genetic correlations with age at first calving (-0.16), dry days (-0.23) while it was positively correlated with calving interval (0.44), gestation period (0.11) and the number of insemination per conception (0.20). Age at the first calving, dry days and gestation period had a positive genetic correlation with fat percenateg (0.03, 0.15 and 0.09 respectively) while calving interval and the number of insemination per conception were negatively correlated with fat percentage (-0.21 and -0.25 respectively).

A feeding trail was conducted to evaluate the effects of diets contaminated with Aflatoxin B1 (AFB1) on the performance and blood enzymes of broiler chickens. In a randomized complete-block design with 4 blocks and 4 treatments, 112 day-old male broiler chicks were divided into 16 groups, 7 chicks per. Treatments consisted of three levels of AFB1 in starter diet (0.4, 0.8, and 1.2 ppm) along with a control group (no AFB1). Feed intake and body weight gain were recorded on a weekly basis. On days 7, 14, 21, and 28, one bird from each replicate was weighed, and killed to collect the blood samples, and to weigh its proventriculus, gizzard, duodenum and pancreas, heart, liver, spleen, bursa of fabricius, and brain. Feeding AFB1 significantly decreased feed intake and body weight gain and increased relative weight of liver (p<0.05). Relative weight of brain decreased on day 7 and then showed a significant increase by day 28 (p<0.05). AFB1 significantly (P<0.05) increased serum activity of aspartate amino transferase (AST) and alanine amino transferase (ALT) and decreased serum activity of lactate dehydrogenase (LDH) enzymes. Generally, this study demonstrated that, alongside other negative effects, AFB1 could also have adverse effect on the brain of broilers.

The effect of dietary protein level and feed restriction on performance, body temperature and hematological values was evaluated, using Ross 308 broiler chicks under heat stress. For this purpose, three dietary treatments were fed to broilers during 21 to 42 days of age. Two treatments consisted of diets with protein levels recommended by NRC, 1994 and 85% of NRC recommendation and were fed ad-lib during the experiment. The third treatment was a feed restriction group that was fed diet with protein level recommended by NRC, but chicks were deprived of feed for 6 hours during heat stress challenge. Birds had free access to water. Results indicated that lowering protein content or feed restriction had no significant effect on body weight gain (P>0.05). Feed restriction resulted in significantly decreased feed intake, improved feed conversion and energy efficiency ratio, and decreased body temperature after heat stress challenge at 24 and 32 days (P<0.05). Lowering protein of diet and feed restriction resulted in significantly decreased protein intake, improved protein efficiency ratio and increased hematocrit and blood uric acid (P<0.05). Sex had no significant effect on body temperature and hematological values (P>0.05). Heat stress significantly increased body temperature, hematocrit and glucose and uric acid values.

The endogenous selection and determination of return reference level is important in specifying risk efficient set. Thus, using multi-objective programming, Target–MOTAD in the framework of Mean-PAD and maximin parametric analysis models was established to obtained reference level of return endogenously. To determine non–inferior set for the farmers understudy, at first, the pay-off matrix was obtained through maximizing objectives under consideration. Then, upper and lower bounds of non-inferior set were determined using non- inferior set estimation (NISE) technique. The results obtained from maximin model indicated that Min and Max of maximin model were 270252 and 217753 thousands Rials, respectively. Furthermore, a subset of non-inferior set was obtained using different return reference levels. Comparing the results of model and the current farmers' plan showed that the current acreage of crops, except for sugar beet was approximately placed in the range determined by the model. In addition, the results also indicated that farmers' plan could be a non- inferior set. Considering the importance and also scarcity of water in the study area, average water return in the farmers' plan was compared to non-inferior set which included all the upper and lower non-inferior set. The results showed that farmers obtained 18150 Rials per hours of used water. However, average water return changed the range of 19100 to 30200 Rials for non-inferior set, indicating that farmers are able to use water more efficiently. The results also showed that changing farmers' cropping pattern is a complicated task and that it is necessary to have a systematic view in ordere to achieve desirable change.

The objective of this study was to evaluate the strategies for groundwater resources management, including competition groundwater pumping, optimal control in groundwater pumping, groundwater use and tax policy, water users' participation in groundwater pumping control, and cooperation among government and water user associations in Narimany plain located in Khorasan Province. Irrigation water demand of sugar beet growers was estimated for empirical assessment of the strategies. The results indicated that among the strategies, groundwater use and tax policy may lead growers to sustainable use of groundwater resources. Furthermore, the results showed a desirable strategy is affected by cultural, social, and economic characteristics of growers and general prevalent conditions of society. Moreover, each strategy calls for its obligations, for instance, it is necessary to have an efficient taxation system for the proposed strategy. Hence, by internalizing the external cost of groundwater overdraft (that is taxing water users) government can force them to consider the adverse effects of their decisions on other producers.

Potatoes are the third most important food crop in Iran. But fluctuations in the production of potato have made imbalances in supply and demand. Lack of appropriate planning for cultivation and marketing operation and farmers’ little knowledge of marketing provides a ground for uncertainty about marketing. To compete successfully in markets, knowledge on marketing is necessary. Succeeding in markets is possible by conducting the marketing educational programs. The broad objective of most marketing educational programs is to help producers modify production and marketing. The first stage in planning of marketing programs is to determine the educational needs. Therefore, needs assessment before planning and conducting to programs is necessary. In this study the educational needs of potato farmers regarding marketing have been considered. The descriptive- correlational research methodology was used in this study. The target population included potato farmers from Ajabshir Township, East Azerbaijan Province. A random sample of 110 potato farmers was selected by multistage cluster random sampling method for completing the questionnaires. Research results indicated that respondents’ technical knowledge in marketing is low especially in pricing and marketing. The most important educational needs of respondents were marketing and pre-harvest activities. The independent variables such as age, literacy rate, yield rate, experience of potato farming and size of potato farms did not have any significant relationship with educational needs. Based on respondents’ opinions, the best educational method was meeting agents on farm and conducting the educational courses.

In this study wholesale prices of selected crops, namely, tomato, onion and potatoes in Fars province were predicted for various time horizons by using common methods of forecasting and artificial neural networks (ANN). Monthly data from September 1998 to June 2005 period were obtained from Ministry of Jihad-e Agriculture. For comparing different methods data selected from September 1998 to December 2004 were utilized, and latest six - month data were mainly used to monitor the power of prediction. The MAE, MSE and MAPE criteria were used for comparing the ability of different forecasting methods. Results of this study showed that ANN had the lowest error in prediction of prices for one - to three - month periods, but for six - month prediction, all forecasting methods were not statistically different.

To detect the rice paddis areas in Isfahan region, the IRS-1D data from PAN, LISS III and WiFS time series were used. Geometric, atmospheric, radiometric and topographic corrections were applied to various images from 2003 to 2004. Necessary preprocessing and various analyses as well as time series composite image analyses were applied and field sampling was done for appropriate times in 2003 and 2004. Image classification was applied using suitable training sites in various images. The SWIR band capabilities were useful for NDWI (Normalized Difference Water Index) to detect the rice paddies. On PAN and LISS III images, urban areas, roads, agricultural lands, non cultivated farms, rocks and brackish soils are detectable. The error matrix was calculated to assess the produced map accuracy using the ground truth data. The total classification accuracy was %91 and the Kappa index value was %89. The rice paddy areas was about 19500 ha in 2003, detected through LISS III data, and 20450 ha through WiFS data. The paddies were 21670 in 2004 through WiFS data. The results of this study confirmed that one can use the LISS III data to detect and determine the rice paddys areas with high accuracy, and WiFS data to estimate the paddies areas with acceptable accuracy.