1 2251-8517 722 General Study of Labyrinth Spillways with Curved Planform M. Yasi M. Mohammadi 1 10 2007 11 41 1 13 09 01 2008   A labyrinth spillway is an overflow spillway to regulate and control flow in canals, rivers and reservoirs. The main hypothesis for the development of such a spillway is to increase the discharge per unit width of structure for a given headwater. This type of structure is often an efficient alternative to a gated-spillway type where either the increase of the flood-passage capacity or the control of the water surface upstream is concerned. This study was aimed to investigate the hydraulic performance of labyrinth spillways of general trapezoidal planform with simple curved apexes. In the experimental work, twelve spillway models with double cycles were considered using three different curved apexes (R/w= 0.15, 0.2, 0.25), each with four different crest heights (w/P= 1.5, 2, 3, 4). Based on the cited recommendations, the length magnification was set to a constant ratio of (l/w= 3) the crest shape was to be of a semi-circular form with simple radius (r= 15 mm) and the spillway walls were vertical with the thickness of T= 2r. An intensive experiment was carried out over a wide range of flows, providing 720 flow data ranging from free flow to submerged flow conditions. 1D flow equation was presented using combined mathematical and dimensional analysis. A coefficient of discharge, Cd, was introduced to represent the influence of the effective geometric and hydraulic parameters on the flow capacity over the spillway. Modular limit was also controlled to see whether the flow over the spillway would be submerged. The results of the study indicate that the modified curved planform of the spillway apexes with consistent divergence in the downstream channel introduces a significant improvement in the flow efficiency over the labyrinth spillways. Spillways with narrower curved apexes (i.e. R/w≤ 0.2), and with the vertical-aspect ratio of (2≤w/P<3) provide more stable and higher hydraulic performance than any other labyrinth planforms over a wide range of flows (i.e. 0.1<H0/P<0.6). In terms of the flow capacity, the proposed spillway model is shown to be more efficient than other zig-zag planforms (i.e. triangular and trapezoidal shapes) with an identical crest length.
723 General Investigation of Yield and Water Use Efficiency of Potato with Tape and Furrow Irrigation S. Akhavan S. F. Mousavi B. Mostafazadeh-Fard A. Ghadami Firoz Abadi 1 10 2007 11 41 15 27 09 01 2008 To investigate yield and water use efficiency (WUE) of potato with tape and furrow irrigations, an experiment was performed at Hamadan Agricultural and Natural Resources Research Center (Ekbatan station) in 2004. The experiment was arranged in a split-plot experimental design based on completely randomized block with 3 replications of irrigation water amount as the main factor (75%, 100%, 125% of cumulative evaporation from class A pan) and sub-factor of irrigation method [including tapes in the middle of furrow ridge on soil surface (TD0), tapes in the middle of furrow ridge at the depth of 5 cm (TD5), tapes on the sides of furrow ridge on soil surface (TS0), and furrow irrigation (F)]. The results indicated that yield of potato increased with increasing water use. Regardless of irrigation method, maximum (32.51 ton/ha) and minimum (19.33 ton/ha) yield of potatoes was achieved with 125% and 75% irrigation water treatments, respectively. The lowest yield (21.35 ton/ha) was obtained in furrow irrigation and the highest yield (28.91 ton/ha) belonged to tape irrigation (TD5 treatment). The highest WUE (4.68 kg/m3) belonged to tape irrigation (TD5 treatment) and the lowest WUE (3.32 kg/m3) belonged to furrow irrigation (F). The difference in WUE between 75% and 100% irrigation water treatments was not significant. The highest WUE (4.49 kg/m3) was achieved in treatment 125%. Also, it is more economical to use irrigation water treatment of 125%, as compared with other irrigation water treatments. 724 General Comparison of MSM Model for Prediction of Potential Evapotranspiration of Maize with FAO Methods A. Majnooni-Heris Sh. Zand - Parsa A. R. Sepaskhah A. A. Kamgar-Haghighi 1 10 2007 11 41 29 42 09 01 2008 Optimal crop water requirement is needed for precise irrigation scheduling. Prediction of crop water requirements is a basic factor to achieve this goal. In this study, maize potential evapotranspiration (ETp) was prediced by maize simulation model (MSM). Then, it was evaluated and validated using experimental field data obtained in Agricultural Research Station of Shiraz University (Bajghah, Fars province) during 2003 and 2004. Comparison of measured volumetric soil water content with predicted values by MSM model in 2003 and 2004 indicated that this subroutine (prediction of maize evapotranspiration) did not need modification. Also, daily potential evapotranspiration of maize was estimated by using Penman-Monteith equation considering single and dual crop coefficients. Comparison between the results of predicted ETp by MSM model, calculated ETp by Penman-Monteith, and measured irrigation water and soil water content indicated that the prediction of ETp by MSM model was satisfactory. Model prediction of seasonal ETp, potential transpiration (Tp) and soil evaporation (E) were 831, 536 and 329 mm, respectively, in 2003, and 832, 518 and 314 mm, respectively, in 2004. The values of ETp, Tp and E calculated by Penman-Monteith method using dual crop coefficients were 693, 489 and 205 mm, respectively, in 2003, and 700, 487 and 213, respectively in 2004. Maximum rate of predicted potential ETp, Tp and E were 11.1, 8.2 and 5.1 mm d-1, respectively in 2003 and 13.0, 9.0 and 4.0 mm d-1, respectively in 2004. The values of calculated seasonal ETp by Penman-Monteith method using single crop coefficient were 615 and 632 mm in 2003, and 2004, respectively. Comparison between the results of predicted ETp by MSM model, calculated ETp by Penman-Monteith equation with single and dual crop coefficients (FAO-56) and measured values of irrigation water and soil water contents of root depth indicated that FAO-56 methods underestimated the ETp. 725 General Fluoride Distribution in Groundwater, Soil and Some Crops in Isfahan Region N. Mirghaffari H. Shariatmadari 1 10 2007 11 41 43 51 09 01 2008 Concentration of soluble fluoride in groundwater, soil, and some crops in Isfahan region was determined by Ion Selective Electrode (ISE) method. The mean fluoride concentration of water samples in the study area was 0.3 and 0.05 mg L-1 in the spring and summer, respectively. These values are in an acceptable limit for irrigation, whereas for drinking water, they are in deficiency range. The average and maximum concentrations of soluble fluoride in soil samples were 1.0 and 3.2 mg kg-1, respectively. In general, the spatial distribution of fluoride in soils showed that fluoride content around major industrial centers such as Isfahan Steel Factory, Mobarakeh Steel Co., and Isfahan oil refinery was higher than other sites. The minimum and maximum fluoride contents of crops were observed in alfalfa as 0.2 and in corn as 4.2 mg kg-1, respectively. Tomato had the highest mean concentration of fluoride as 3.6 mg kg-1. The fluoride concentration in plants positively correlated with the fluoride concentration in irrigation water and soil (P < 0.01) and negatively correlated with cation exchange capacity of soil (P < 0.05). 726 General Effect of Salinity and Cow Manure (Organic Matter) on Distribution and Concentration of Zinc Species in Soil Solution A. Dehghani A. Fotovat GH. Haghnia P. Keshavarz 1 10 2007 11 41 53 61 09 01 2008 727 General Improvement in Estimation of Soil-Moisture Characteristic Curve Based on Soil Particle Size Distribution and Bulk Density H. R. Fooladmand 1 10 2007 11 41 63 73 09 01 2008   Soil particle size distribution and bulk density are used for estimating soil-moisture characteristic curve. In this model, soil particle size distribution curve is divided into a number of segments, each with a specific particle radius and cumulative percentage of the particles greater than that radius. Using these data, soil-moisture characteristic curve is estimated. In the model a scale factor, a , is used which may be considered as a constant, or obtained by logistic or linear procedures. F or most conditions, soil particle size distribution curve is not available, but only the percentages of clay, silt and sand could be obtained using soil textural data. In this situation, at first a precise soil particle size distribution must be developed, based on which the soil-moisture characteristic curve can be predicted. According to the previous studies, using particle radius of 999 µ m is more appropriate than radius 125 µ m. Also, adjusted coefficients for estimating soil particle size distribution curve for radii 1 to 20  µ m was obtained. In this study, using the soil textural data of 19 different soils from UNSODA database, soil-moisture characteristic curve of each was estimated with logistic and linear methods based on initial and adjusted soil particle size distribution estimation. The estimated values were compared with the measured data. The results indicated that for most soils, using the combination of logistic and adjusted particle size distribution estimation procedures is more appropriate than the previous methods. 728 General Effects of Wetting and Drying, and Cultivation Systems on Potassium Fixation in Some Khouzestan Soils S. Jafari M. Baghernejad 1 10 2007 11 41 75 90 09 01 2008 Sugarcane (Saccharum officinarum L.)‌ and rotational crops have been cultivated without potassium fertilizers for many years in southwestern Iran. Although potassium was removed from this soil, no response has been reported to K fertilizers by crops. This study was conducted to evaluate the effects of wetting and drying, and cultivation systems on potassium fixation in some Khouzestan soils. The results showed that expandable clay mineral was observed in cultivated soils but not in the non-cultivated soils. This may be related to irrigation, and cultivation practices in this soils. By adding K and sequential wetting and drying the amount of K-available increased in sugarcane, rotational cropping and uncultivated soils from 132.6, 226.2 and, 171.6 mgkg-1 to 266, 447 and 628, respectively. These results showed that more K can be fixed after cultivating soils, especially by sugarcane, but available K increased by adding K. All surface soils had higher K fixation capacity than subsurface ones. Also, by application K to these soils, the amount of K fixation decreased with increasing wetting and drying times. The K fixation increased by the increase of cation exchangeable capacity. Significant difference was observed between cultivation system and depth of sampling in 1% levels. High K fixation can be attributed to illite minerals depleted from K. Mica-like minerals formed after adding K, and wetting and drying cycles. Amount of K fixation by clay particle samples was more than the same soil samples but in both the same trend was observed for K fixation. Also, drying and wetting decreased K fixation in the last periods. It may be due to trapping K in the interlayer positions. 729 General Short-Term Tillage and Manure Influences on Soil Structural Properties A. Safadoust M. R. Mosaddeghi A. A. Mahboubi A. Nouroozi Gh. Asadian 1 10 2007 11 41 91 101 09 01 2008 The increased potential for soil erosion and compaction due to continuous row crop production and intensive tillage is causing some concern and has led to the consideration of reduced tillage techniques as part of the solution. The objective of this study was to investigate the short-term (one-year) influences of different management practices on the physical properties of a sandy loam soil under corn crop. Treatments were the combinations of three tillage systems (no-till, NT chisel plow, CP and moldboard plow, MP) and three composted cattle manure rates [0, 30 and 60 ton (dry weight) ha-1]. The experiment was carried out in a split-plot design. Three replicates of the treatments were applied in a randomized block design. Saturated hydraulic conductivity (Ks), total porosity (TP), macro-porosity (Macro-P), micro-porosity (Micro-P) of soil and mean weight diameter (MWD) of aggregates, were measured to a depth of 22.5 cm when 100 percent of the tassels appeared. Tillage and manure combination had significant effects on Log[ Ks], TP, Macro-P and Micro-P. The MP system increased pore space and continuity due to complete inversion and loosening, and as a result Ks, TP, Macro-P and Micro-P were higher than NT system. Higher Macro-P observed for CP might have caused higher Ks versus MP. Reduced tillage systems increased MWD and the increment of manure caused an increase in MWD over all tillage treatments. The results indicate short-term positive effects of manure application on soil pore size characteristics and aggregate stability under moldboard and chisel plowings in the region. 730 General Effects of Climate and Long-Term Grazing Exclusion on Selected Soil Biological Quality Indicators in Rangelands of Central Zagros M. Sheklabadi H. Khademi M. Karimian Eghbal F. Nourbaksh 1 10 2007 11 41 103 116 09 01 2008 The effect of overgrazing on vegetation changes in central Zagros has been studied by a few scientists, but there is no detailed information on the impact of such practices on soil properties. The objective of this study was to assess the effect of climate and grazing management on selected soil biochemical properties. Fourteen experimental range sites protected against grazing as well as their adjacent overgrazed sites in Chadegan, Pishkuh and Poshtkuh were selected. In each site, samples were collected from the depths 0-5 and 5-15 cm. Soil organic C (OC), microbial biomass C (MBC), total nitrogen (TN), organic C to total N ratio (C/N), microbial biomass C to organic C ratio (Cmic/Coc) and metabolic quotient (qCO2) were measured and/or calculated. The results showed that the lowest SOC, MBC, TN and Cmic/Coc occur in Chadegan due to low fresh materials input. The above parameters in Pishkuh and Poshtkuh regions are 2.5 to 3 times greater than those in Chadegan area. Grazing intensity in Pishkuh is less than that in Poshtkuh region and there is no significant difference between grazed and protected sites in Pishkuh. But, there is a significant difference between grazed and protected plots in Poshtkuh due to a higher grazing intensity. Higher Cmic/Coc and lower qCO2 suggest that the quality of organic matter is better in Poshtkuh and Pishkuh. In conclusion, highly degraded rangelands in Pishkuh and Poshtkuh seem to be able to recover very quickly with proper management, while Chadegan region needs a much longer period of time to restore. 731 General Performance of a Bentleg Subsoiler with Shallow Tines in a Clay Soil M. H. Raoufat M. Kazemi Najaf Abadi 1 10 2007 11 41 117 129 09 01 2008 The present research was intended to alleviate the problems and costs of deep tilling in sugarcane production in Mian-Ab sugarcane farms located in Khuzestan province, Iran. The main objective was to investigate the feasibility of subsoiling operations with bentleg subsoiler (BLS) equipped with shallow tines, a combination expected to increase the critical depth resulting in less power consumption and improved soil physical conditions. Six treatments arranged in a completely randomized block design were used to measure the draft force (except for the bulldozer mounted rippers), disturbed soil cross-sectional area and penetration resistance. The treatments included (1) subsoiling with rippers mounted on bulldozer, (2) BLS without attachment, (3), and (4) BLS equipped with single tine at working depths of ½ and ⅓ of target depth, (5) and (6) BLS equipped with two tines at ½ and ⅓ target depth. The experiment was replicated three times. The results indicated that BLS without attachment had the highest draft requirement as compared with other BLS treatments with shallow tines. In general, tine attachment resulted in less draft mainly due to displacement of critical depth to lower soil zones. Increasing the number and depth of shallow tines resulted in less draft force. The BLS equipped with two tines working at ½ target depth exhibited minimum drawbar power. The inclusion of shallow tines resulted in 21% reduction in drawbar power requirement as compared to BLS without tine attachment. The cross-sectional area of the soil tilled by ripper was minimum. Furthermore, the tilled area was not uniform and subsequent subsoiling operations were needed. The average soil cross-sectional area per unit width was improved by BLS treatments by a factor of 2.3 as compared with that of ripper. The highest cone index was obtained in plots tilled by ripper the BLS reduced this index in a significant manner. The soil worked with subsoiler equipped with tines exhibited the least resistance. The range of wheel slippage for BLS treatments was 12-16% which lies in the upper end of the recommended range for optimum traction efficiency. The proposed idea proved prominent in subsoiling fine textured compact soils. 732 General Determination and Evaluation of the Flowering Time, Pollen Quantity and Quality in The Some Male Genotypes of Pistachio (Pistacia vera L.) F. Kamiab A. Vesvaei A. Ebadiand B. Panahi 1 10 2007 11 41 131 140 09 01 2008 This research was conducted in order to select male genotypes of pistachio with good performance. The study was performed on 10 genotypes in regard to their flowering time, pollen quantity and quality. The results indicated that flowering times of P1, P2 genotypes were simultaneous with Kallehghochi P3, P4, P5 genotypes with Ahmad Aghaii P6 and P7 genotypes with Ohadi and P8, P9, P10 genotypes with Akbari. Inflorescence weight showed big differences between them, ranging from 4.5gr for P6 to 1.66gr for P8. The amount of pollen per inflorescence also showed big difference, ranging from 71mg for P2 and 267mg for P5. In order to determine the percentage of pollen germination, a medium consisting of sucrose, agar and boric acid was used. The percentage of pollen germination also showed big difference, ranging from 30%for P3 and P4 and 85% for P10. Stored pollen at 4°C temperature showed 30% germination after one month and 0% germination after three months. The results also indicated that the percentage of pollen germination in culture medium without boric acid was lower, compared with other treatments. The viability of pollens collected from cutting inflorescences kept in water bottle was higher than that obtained from dried inflorescences maintained in room condition. 733 General Evaluation of Drought Tolerance Indices in Sesame Lines M. Golestani H. Pakniyat 1 10 2007 11 41 141 150 09 01 2008 To investigate genetic variation, and identification of tolerant genotypes according to quantitative indices of drought tolerance, 8 sesame genotypes were tested in a randomized complete block design with three replications under optimum and limited irrigation at the Research Station of College of Agriculture, Shiraz University. Based on the potential yield and yield under stress, quantitative indices of drought tolerance such as mean productivity (MP), geometric mean productivity (GMP), harmonic mean (HM), stress tolerance index (STI), stress susceptibility index (SSI) and tolerance index (TOL) were determined. The result of analysis of variance exhibited highly significant differences among the genotypes for all the indices measured, and yield under optimum and limited irrigation, indicating the existence of genetic variation among genotypes, and thus the possibility of selecting drought tolerant genotypes. Mean comparison displayed that the highest potential yield, stress yield, MP, GMP, HM and STI were related to the genotype number 5. Correlation analysis between indices, mean potential and stress yields indicated that every four indices are suitable for screening the genotypes. Based on these indices and higher yields under optimum and limited irrigation the best drought tolerant genotypes were identified to be genotypes number 4 and 5. Multivariate biplot indicated that the genotypes number 4 and 5 were located next to the vectors of drought tolerance indices, including MP, GMP, HM and STI. Cluster analysis showed genetic distance among genotypes. As a result, genotypes number 4 and 5 were identified as drought tolerant and genotypes number 1, 2 and 3 as susceptible to drought. 734 General Analysis of the Genetic Diversity Among Some of Iranian Melon (Cucumis melo L.) Landraces Using Morphological and Rapd Molecular Markers E. Feyzian M. Jalali Javaran H. Dehghani H. Zamyad 1 10 2007 11 41 151 163 09 01 2008 Germplasm collection is the base of plant breeding. Iran is one of the most important centers of genetic diversity due to different climates and the old civilization.In this study we decided to collect melon accessions. The north and center of Iran were selected for this purpose. Fifteen qualitative and six quantitative traits were measured on thirty eight accessions. The cluster analysis by the use of UPGMA method and Jaccard coefficient helped separate the horticultural groups of Cucumis melo L. (Cantaloupensis, Inodorus, Flexousous, Reticulatus). The relationship between 30 of these accessions was assessed using 10 RAPD primers. The polymorphism was determined to be19%. The cluster analysis could not separate the horticultural groups of Cucumis melo L., showing that these groups are closely related. However, VB84 primer separated the tow Snakemelon. 735 General Evaluation of Conventional Management of Fallow-Forage Barley and Sugar Beet-Forage Barley Rotations and its Effect on Density and Distribution of Different Species of Weeds A. Siah-Marguee M.H. Rashed-Mohasel M. Nasiri-Mahallati M. Banayan-Aval A. A. Mohammad-Abadi 1 10 2007 11 41 165 175 09 01 2008 This study was performed in two barley fields, in Experimental Station, Agricultural College of Ferdowsi University of Mashhad in 2003. Sampling was done by systematic method in which samples were taken from the corners of 7m*7m grids using 0.5m 0.5m size quadrates in three stages (pre herbicide, post herbicide and pre harvesting stages). The results indicted that the density of annual weed seedlings in sugar beet- barley rotation was more than fallow- barley rotation, and the density of perennial weed seedlings in fallow-barley rotation was more than sugar beet- barley rotation. Map of species distribution and density confirmed patchiness distribution of the weeds. The shape and size of patches differed based on the field and weed species, but spatial distribution did not change considerably before and after the application of herbicide. Percentage of free weeds area was 11.5% and 1.5% in fallow-barley rotation and 0.6% and 0% in sugar beet- barley rotation in the first and second sampling stages, respectively. These results indicate beside emphasis on weed infestation. The result also indicates inefficacy of sugarbeet-barley rotation compared to follow-barley rotation. Apparently, the evaluation of management and paying special attention to weed dispersal within the field assist in the implementation of appropriate management strategy, which includes high efficacy, and profit for farmers as well as least damage to crops. 736 General Path Coefficient Analysis of Fescue Seed Yield and its Components Affected by Fungal Endophyte M. M. Majidi A.F. Mirlohi M.R. Sabzalian 1 10 2007 11 41 177 189 09 01 2008 Fescues (Festuca spp) are widely distributed in the temperate regions and are used for turf, forage and soil conservation. Though seed traits are important measures of the effects of endophytic fungi on their host, little information is available in this respect for Festuca. In this study, endophyte-infected (E+) and endophyte-free (E-) clones of the six fescue genotypes were used to investigate the effects of endophyte on seed production. The relationships between seed traits plus direct and indirect effects of components on seed yield were also studied. Endophyte infection resulted in 38.1% to 249% more seed yields in some genotypes, though some were not affected by this symbiotic relationship. Correlations between traits and also results of stepwise regression were influenced by the presence of the symbiotic fungi. Path analysis showed that endophytic fungi changed direct and indirect effects of components on seed yield. In endophyte containing clones, panicle fertility had the most direct effects and number of panicle per plant and seed per panicle the most indirect effects on seed yield. In E- clones, panicle fertility had the highest indirect effects and other components had direct effects on seed yield. The results suggested that breeding strategies for increasing seed yield in fescue should consider the presence or absence of endophyte in germplasm. 737 General Effects of Salt Stress on Germination, Vegetative Growth and some Physiological Characteristics of Canola M. Shamsaddin Saied H. Farahbakhsh A. A Maghsoodi Mude 1 10 2007 11 41 191 203 09 01 2008 In order to study the effects of salinity on germination, vegetative growth and some physiological characteristics of canola cultivars, two experiments were conducted at Research Station of Agricultural College of University of Kerman in 2004. The experimental design was a Completely Randomized Block with four replications. Treatments comprised all combinations of different levels of three factors including variety (Kobra × Regent, Ceres and Okapi), salt type (NaCl, CaCl2) and electrical conductivity of saline solution (0, 4, 8, 12 dS/m). Results of variance analysis showed that salinity has a very significant effect on germination percentage, germination homogeneity, germination rate, rootlet and polomul length at the end of the germination stage. Shoot length, dry weight, diameter and number of nodes per shoot were significantly affected also by salinity at vegetative growth. Regarding the two types of salt, none of the measured traits were significantly different. All the mentioned traits decreased with increasing salinity the highest and the lowest values were recorded at control and at 12 dS/m salinity levels. Membrane ion leakage was the only trait which increased significantly. Comparison of means showed germination percentage and germination homogeneity at germination stage and the number of nodes at vegetative growth stage were affected less than other traits by salinity, and they only decreased significantly with increasing salinity to 12dS/m. The effect of cultivar on these traits was also significant (P<0.001). In both growth stages, cultivars response to salinity was different. At germination stage, Ceres and Kobra * Regent cultivars were the most sensitive and tolerant ones in terms of all traits and there was no significant difference between Okapi and Kobra *Regent. At vegetative growth stage, however, Okapi showed less growth than Kobra * Regent and their difference was significant. It seems that evaluation of traits response at germination stage can not be effective to determine salt tolerance of canola cultivars. 738 General Evaluation of Relationship between Different Traits in Lentils (Lens culinaris Medik) M. Salehi A. Haghnazari F. Shekari H. Baleseni 1 10 2007 11 41 205 216 09 01 2008 In order to evaluate relationship between Different traits in lentils (lens culinaris Medik), a field study was conducted as an RCBD based design with 3 replications on Zanjan University Research Farm during spring of the year 2004. ANOVA analysis revealed significant differences for all characters except for the number of primery branches. Correlation analysis indicated positive and significant correlation between seed yield and harvest index, number of primery branches, pods/plant and biological yield, and grian yield. The result of the factor analysis also showed that the second factor including number of primery branches, pods/plant, grian yield, canopy width and seeds/plant was an important trait involved in the grian yield in lentil. In addition, cluster analysis helped divide the genotypes into four distance groups of large, medium, semi medium and low yields. 739 General Introduction of the Flora and Life Forms of Weeds of Isfahan Vineyards A. Nekouei M. Rahimmalek 1 10 2007 11 41 217 226 09 01 2008 Flora identification of each region plays an important role in the maintenance of natural resources of each country and it is a prerequisite to supplementary phylogenetics and genetic diversity studies. During February 1994 to August 1995, in a two-week interval, vineyards in two districts of Isfahan province, namely Zarinshahr and Tiran & Karvan were visited and weed samples were collected in flowering stages. All collected specimens were identified using specimens present in Herbarium of colleges of agriculture and natural resources of Isfahan University of Technology and other available references. The analysis revealed that in Tiran and Karvan, 84 species belonged to 71 genera and 26 families and in Zarinshahr 62 species belonged to 51 genera and 23 families. Species dominance in both districts belonged to Asteraceae and Gramineae families. Analysis of plant life forms using Raunkiaar method showed that Therophytes with 79.5% and Geophytes with 8.3% were the most frequent life forms in both Zarinshahr and Tiran & Karvan regions. 740 General Evaluation of Genetic Relationship of Some Important Agronomic Traits with Seed Yield in Soybean [Glycine max (L.) Merr.] by Multivariate Analysis Methods V. Narjesi H. Zeinal Khaneghah A. Zali 1 10 2007 11 41 227 236 09 01 2008 Thirty soybean cultivars from different maturity groups were evaluated in a randomized complete block design with four replications in Research Station of College of Agriculture at Tehran University in Karaj in 2004. The purpose was to determine genetic relationship of some important agronomic traits related to seed yield. Analysis of variance showed that there were significant differences among varieties for the traits under study, indicating the existence of genetic variation among varieties. Number of pods/plant, number of seeds/plant and 100-seed weight, all of which are considered yield components, had the highest genotypic correlation with seed yield. Using stepwise regression analysis, 85.6 % of seed yield variation was attributed to four traits, including harvest index, biological yield, protein precent and number of seeds /plant. Harvest index was more important for predicting seed yield compared to other traits based on standardized ßs. Results of path analysis showed that the harvest index and protein precentage had the highest and lowest direct and positive effect (p=0.536), (p=0.008), respectively. Therefore, harvest index may be considered as a selection criteria to improve seed yield in breeding programs. Results of factor analysis showed five independent factors accounted for 80.2 % of total variations in data. The first principle determined 28.2 % of total variation and was designated as phenologic factor. 741 General Effect of Detopping after Pollination and Plant Density on Yield and Yield Components in KSC 704 Cultivar of Corn P. Sharifi M. Tajbakhsh 1 10 2007 11 41 237 245 09 01 2008 To evaluate the effect of plant density and detopping on grain yield, protein content biological yield harvest index, growth indices, number of cob in each plant, No. of row per ear, No. of grain in each row, thousand seed weight of corn (Zea mays L. ar. SC 704), an experiment was conducted at the experimental statues of Research Center of Uremia Agricultural College in 2004. The Treatment design was split plot in randomized complete block design with four replications. The main plots included plant density at three levels (53000, 66000, and 88000 Plants/ha) and the subplets comprised three levels: (1) no detopping (control) (2) removing canopy only and (3) removing canopy and three leaves above the node. Analysis of Variance of data showed that both detopping treatment and plant density influenced the number of kernel per ear ,1000 grain weight, ear weight, total dry weight of biomass, seed yield and harvest index. Canopy detopping led to a marked increase in photo assimilateion import grains. The highest plant density evaluated, 88000 plants per hectare with detopping of three above leaves had the highest number of cobs per square meter. In plant density of 53000 plants per hectare and canopy detopping treatment, the number of grain per ear was greater than other densities. The efficiency of harvest index increased under corn detopping compared with control, and this increase with an increase in photosynthesis contributed to grain yield. It was concluded that major increase in grain yield under high plants density and tassel detopping was due to improvement of physiological indices. 742 General Estimation of Genetic Parameters in Rice Using Different Diallel Methods of Griffing Approach R. Honarnejad 1 10 2007 11 41 247 259 09 01 2008 Six Iranian rice cultivars (Binam, Domsiyah, Shahpasand, Sepidrud, Khazar and Valed 46) were crossed in 1989 in the Iranian Rice Research Institute in Rasht, Iran in a full-diallel design. The F1 progenies together with parents were transplanted in a CRBD in the 5 x 0.75 m plots at plant density of 25 x 25 cm (60 plantlets per plot) in 3 replications. Part of this research was published in 1994 as a half-diallel design and the data of full-diallel, using Griffing approach, is subject of this paper. The analysis of variance showed significant differences among genotypes. The mean of six parents, 15 crosses and 15 reciprocal crosses were analyzed using the four diallel crossing systems of the Griffing approach. The SS of genotypes were separated into GCA for each parent and SCA for each cross using corresponding formula. The additive variance (VA) and dominance variance (VD) values were estimated using the table of variance analysis. The heritability (h2ns) was also estimated from VA and VD variances. The simple variance analysis of “grain yield per plant” and other agronomic traits using each of the 4 diallel crossing methods of Griffing showed significant differences (P < 1%) among genotypes, indicating a sufficient genetic potential of the investigated genotypes. The GCA variance analysis of the lines was significant for all the characteristics, indicating the importance of additive variance (VA) by inheritance of these traits. Using Griffing’s diallel methods 1 and 3, SCA variances for all investigated traits showed significance, whereas in the methods 2 and 4, traits “1000 grain weight” and “tiller per plant” were not significant according to SCA. This also indicates the importance of dominant variance (VD) in most of the traits, except for “1000 grain weight” and “tiller per plant”. The differences among the reciprocal crosses in diallel methods 1 and 3 were also examined where for all the characteristics (except for “deaf grains per panicle” and “length to breadth ratio of brown rice grain”) significant differences were observed, suggesting the possibility of cytoplasmic effect of mother line on the reciprocal crosses. The heritability (h2ns), which indicates the ratio of additive variance (VA) to phenotypic variance (VP), was estimated to be equal to zero due to the absence of additive variance for grain per panicle and the number of days from transplanting to full maturity of grain. The heritability for other characteristics was estimated high or low according to additive variance. For example in all 4 diallel methods the heritability estimation for length to breadth ratio of brown rice grain was relatively high (65 – 71%) whereas for “panicle length” and “grain yield per plant” was relatively low (13 – 48%). The correlation among genetic parameters (VA, VD, D, h2ns ) were generally high and significant. 743 General Evaluation of Interrelationship of Growth Indices and Grain Yield of Five Maize Hybrids under Two Irrigation Regimes in Isfahan J. Nori Azhar P. Ehsanzadeh 1 10 2007 11 41 261 273 09 01 2008 Defining interrelationship of growth analysis factors and yield of crop plants is important in the field crop production practices. This research was aimed at studying growth factors and grain yield of five maize hybrids, consisting of S.C.704, S.C.700, S.C.647, S.C.604, and S.C.301, using two 4-replicate RCBD experiments in Isfahan, in Summer 2004. While one experiment was irrigated normally, the other one was conducted under delayed irrigation conditions. Maize plants were seeded at 95000 plants/ha in 8-row plots, with rows spaced 0.70m apart and 0.15m distance between plants on each row. Delayed irrigation led to a significant decrease in LAImax, LAD, LADLinear and LADs-m, but a significant increase in days to silking. While CGRLinear significantly correlated with LAImax, LAD, LADLinear and LADs-m, a significant correlation was observed between total biomass and grain yield. CGRLinear, LAImax, and LADs-m significantly correlated with total biomass, and grain yield significantly correlated with yield components, harvest index, CGRLinear and LAImax. In conclusion, an increase in LAImax resulted in a higher CGRLinear and in turn a greater total biomass. But, considering no significant correlation between total biomass and harvest index, it appears that with the genotypes and under conditions of the present study, allocation of dry matter to grain production did not correlate with the leaf area attributes of corn. 744 General Evaluation of Salt Tolerance in Three Varieties of Corn E. Dehghan A. Naderi 1 10 2007 11 41 275 284 09 01 2008 This study included two experiments conducted in 2000-2001 for surveying the effects of saline water irrigation on yield and yield components in corn varieties. Experiments were conducted in a silty-clay soil in Ahwaz Agricultural Research Center. First experiment was conducted as a split plots and randomized complete blocks design in three replications. Main plots included salinity levels 2, 4, 6 and 8dS/m and subplots included three single cross hybrids of corn 704, 711 and 647. In the other experiment the effects of saline water 8dS/m at different growth stages including the stage of planting to plant establishment. (G1), flowering and pollination (G2) and grain filling (G3), were evaluated. The results of the first expriment showed that there was very significant difference among water salinity levels for yield, thousand kernel weight, percentage of corn fertility and percentage of plants containing corn. The highest and lowest grain yield were obtained for salinity levels 2 and 8dS/m treatments respectively. Differences among varieties and interaction of treatments were significant for grain yield, and highest grain yeild was obtained for 704 and 711 varieties on saline water 2dS/m. The results of the other expriment showed that highest and lowest tolerance to irrigation with saline water on corn were G3 and G1 growth stages respectively. Consequently, hybrids 704 and 711 were more sensitive than the 647, but the obtained yield, suggests that 704 and 711 hybrids can be cultivated under these conditions. 760 General Effect of Plant Growth Promoting Potentials of Azotobacter chroococcum Native Strains on Growth, Yield and Uptake of Nutrients in Wheat S. Rajaee H. A. Alikhani F. Raiesi 1 10 2007 11 41 285 297 09 01 2008 Azotobacter chroococcum is an important PGPR (Plant Growth Promoting Rhizobacteria) producing compounds needed for plant growth. The aim of this research was to study the effects of different native strains of Azotobacter chroococcum on growth and yield of wheat under greenhouse counditions. Seeds of spring wheat (Triticum aestivum L. var. Pishtaz) were inoculated with some Azotobacter chroococcum strains capable of producing IAA, HCN, sidrophore and fixing molecular nitrogen. The inoculation of wheat with those strains had a positive, significant effect on biological yield, seed protein percentage, thousand seed weight, leaf area, N, P, Fe and Zn uptake, in particular, by wheat. The increased growth of wheat was most likely due to the production of IAA and enhanced nitrogen fixation by inoculated strains. Some strains of Azotobacter chroococcum native to Chaharmahal va Bakhtiari are established as PGPR. Results also support the efficiency of Azotobacter chroococcum as an important biofertilizer in wheat cropping systems. The selected strains had a significant effect on wheat growth and yield, including biological yield and seed quality under greenhouse counditions. This beneficial effect of Azotobacter chroococcum on wheat is attributed mainly to IAA production and, to some extent to non symbiotic nitrogen fixation in the rhizosphere. So, these strains can potentially be used to improve wheat nutrition of micronutrients such as Fe and Zn, in particular. 745 General Effects of Leaf Extract of Reynoutria sachalinensis on the Defense Responses of Host in Cucumber-Powdery Mildew Interaction A.H. Jamali Zavareh A. Sharifi Tehrani M. Mohammadi 1 10 2007 11 41 299 307 09 01 2008 One of the properties of systemically acquired resistance in plants is their concomitance with the biochemical changes including enhancement of activities of defense-related enzymes. The leaf extract of Reynoutria sachalinensis (F. Schmidt) Nakai is known to be an effective compound for the control of a few plant diseases particularly powdery mildew of cucurbits (caused by fungal pathogen Podosphaera fusca), by inducing host defense responses. In the present investigation, the effects of this extract on some defense responses of cucumber plants were studied via in vivo tests. Changes of defense responses in the extract treated-cucumber plants, with or without pathogen inoculation, were studied and compared with those of non-treated control plants. Results indicated that specific activity of peroxidase increased significantly in treated tissues. Enhancement of enzyme activity showed the same patterns in both the pathogen inoculated- and non-inoculated-plants thus the pathogen attack did not affect the enzyme activity. Specific activity of phenylalanine ammonia-lyase in the non-inoculated extract treated-plants showed a transient fast increase during 24 hours after the treatment, whereas in the inoculated ones, it showed a permanent slow increase probably due to the interaction between extract treatment and pathogen attack. Phenolic content of extract treated-plant tissues, despite small fluctuations, did not show any definite pattern of changes. 746 General Biological Control of Vascular Wilt Disease of Carnation Caused by Fusarium oxysporum f.sp. dianthi by Bacillus and Pseudomonass Strains Isolated from Rhizosphere of Carnation E. Karimi H. Rouhani D. Zafari1 Gh. Khodakaramian M. Taghinasab 1 10 2007 11 41 309 320 09 01 2008 In order to study the biological control of carnation vascular wilt disease caused by Fusarium oxysporum f.sp. dianthi, 141 bacterial strains were isolated from carnation rhizosphere, and their antagonistic activity was evaluated against fungal pathogen in dual culture method. Among the tested strains, 16 strains showed antagonistic activity seven of them with more activity were selected for further investigation. Based on phenotypic features, strains E31 and E57 were identified as Bacillus cereus E76, E93, E102 and E121 as Bacillus subtilis and E130 as Pseudomonas fluorescens bv. III. All bacterial strains inhibited mycelial growth of F. o. f. sp. dianthi by production of non-volatile and volatile metabolites under laboratory condition. Microscopical analysis showed that all strains caused deformation of pathogen mycelium, and metabolites of these strains reduced conidia production rate and as well as the ability of conidia germination. In the in vivo tests, in sterilized and nonsterilized soils, the effect of bacterial strains was studied on disease severity, percentage of healthy plants and the growth rate of plants using soil inoculating and root-dipping into bacteria-methyl cellulose mixture methods. The E57 and E121 strains, in both methods, and E130 in root-dipping method showed highest effect on decreasing of disease severity and increasing of healthy plants percentage. Strains E57, E121 and E130 significantly increased total dry weight of carnation. Maximum dry weight was obtained by E57 and E130 in soil inoculating and root –dipping methods respectively. 747 General Estimating the Number of Sex Alleles in Honeybee Colonies in Central Region of Iran and its Relationship with Stored Pollen, Colony Population and Honey Yeild R. Sepehri GH. Tahmasebi M. J. Jalali Zonoz 1 10 2007 11 41 321 332 09 01 2008 During the honeybee breeding project in central Iran, sex alleles homozygoty and sex alleles number in the third generation of 364 colonies were studied in 2003. Sex alleles homozygoty was measured based on Ruttner (1988) and Tarpy and Page (2002) methods. The total area of worker brood area, stored pollen, and drone brood area were measured on the combs. The whole extracted honey weight and remaining honey in the combs were evaluated as honey production of colonies. Adult population was evaluated based on the number of full combs of adult honeybees. The results showed that sex alleles, average homozygoty and number in the colonies were 18.83% and 5.32 respectively. The results showed no significant correlation between homozygoty of sex alleles or sex alleles number and stored pollen ( P > 0.05 ) , but significant negative correlation between sex alleles homozygoty and colony population, total brood area and honey yield ( P < 0.01 ) was observed. So introduction of new sire colonies in the mating Isolated area is essential to prevent sex alleles homozygoty and also performance of honeybee colonies from decreasing. 748 General Reproductive Parameters of Aeolesthes sarta Solsky (Col., Cerambycidae) on Ulmus Carpinifolia Borkh. under Laboratory Conditions A. Mazaheri B. Hatami J. Khajehali S. E. Sadeghi 1 10 2007 11 41 333 343 09 01 2008 Sarta longhorned beetle, Aeolesthes sarta, is one of the most destructive wood borer pests of fruit and shade trees in Iran. In this research, the reproductive parameters were studied under laboratory conditions. Fifteen pairs of newly developed adults (1-2 days after emergence from overwintering sites) were caged separately on 15 logs of Ulmus carpinifolia and fertility table was made using this data. The results showed that 3.9±0.2 days after emergence, females began to oviposit for 16.6±0.6 days, as oviposition period. Mean number of laid eggs was 122.6±17.5 per female. The mean longevity of male and female was 26±0.6 and 29.4±0.4 days, respectively. Females had no mortality during oviposition period, so gross reproductive rate (GRR) and net reproductive rate (R0) (famale/female/generation) were equal (61.6±8.7). Intrinsic rate of increase (rm), mean generation time (T) and doubling time of the population (t) were 0.0067±0.24-5 famale/female/day, 612.5±0.4 and 102.7±3.6 days, respectively. The finite rate of increase (λ) (female/female/day) was 1.006±0.24-5. Intrinsic rate of increase (rm) was very low (0.00672), because of longer lifetime of females (mean 602 days), low longevity during reproductive period (maximum 22 days) and long mean generation time (612.5 days). 749 General Bean Polygalacturonase-inhibiting Proteins Inhibits Polygalacturonase from Fusarium Oxysporum and Ascochyta rabiei of Chickpea A. Hosseinzadeh Colagar A. Mostafaie M. Motallebi M.R. Zamani 1 10 2007 11 41 345 356 09 01 2008 Plant pathogenic microorganisms produce a variety of enzymes capable of degrading different polysaccharides of the plant cell walls. Pathogens use these enzymes to penetrate and colonize host cells. Polygalacturonases are thought to be the first cell wall-degrading enzymes secreted by pathogens when they grow on plant cell walls. Oligogalacturonic acids with the polymerization degrees of 10 to 13 are intermediate products of pectin degradation by the action of polygalacturonases and are known to activate plant defense responses. PG- inhibiting proteins (PGIPs) present in the cell wall of many plants increase the stability of oligogalacturonic acids in the tissues by modulating fungal PG activities. These glycoproteins of the plant cell extracellular matrix retard the advancement of fungal hyphae, reduce tissue maceration, and prevent colonization of pathogen. In this study, Phaseolus vulgaris PGIPs were extracted from hypocotyle of Derakhshan and Naz bean cultivars. PvPGIPs were purified by afinity chromatography and analyzed by SDS-PAGE. Three major bands in the range of 47-55 kDa were detected. Average yield of The affinity-purified PGIPs was 1.68 mg per 100 gram of fresh bean hypocotyle. The inhibitory effect of PGIP was assayed on the PG activities of highly virulent isolates of Fusarium oxysporum (F15) and Ascochyta rabiei (IK04). The inhibitory activity of crude PGIP from Naz and Derakhshan cultivars on polygalacturonase activity of F. oxysporum was 18 and 28 units, respectively. These inhibitory activities increased to 40 units after purification. The inhibitory effect of crude PGIPs from both these two cultivars on PG activity of A. rabiei was 9 units, while purified PGIPs inhibited this PG activity to 18 and 29 units, respectively. 750 General Effect of Package Type and Fat Concentration on Vitamin A Losses and Sensory Characteristics of Milk Fortified with Vitamin A R. Sadeh M. Azar M. Shahedi M.T. Mazloomi 1 10 2007 11 41 357 364 09 01 2008 Homogenized milks at 0.5 and 2.5% fat content were each fortified with three levels of Vitamin A palmitate at 3000, 4000 and 5000 IU/L. Vitamin was added just before homogenization and then pasteurized milks were packed in polymeric pouches and glass bottles. All samples were refrigerated at 4-5 °C for 48 hours. Any reduction in vitamin A level was monitored using HPLC, while sensory evaluation was conducted in order to rank the samples. ANOVA and Friedman analyses indicated that fat content along with package type had a significant effect on the residue of vitamin A. The loss of vitamin A was significantly higher in 0.5% milk either packed in polymeric pouch or glass bottle. However, besides fat concentration, more vitamin A was lost in glass bottles rather than polymeric pouches. Sensory evaluation showed that milk fortification had no adverse effects on color and flavor of the product. 751 General Influence of some Physical and Chemical Parameters on Flow Behavior of Salab Gum (Orchidaceae orchis) Solutions S. Abassi S. Foroughinia 1 10 2007 11 41 365 372 09 01 2008 Salab gum is a hydrocolloidal compound which can be extracted from detached roots, tubers as well as rhizomes of Orchidaceae family. Apart from its applications in pharmaceuticals it has many potential usages in foodstuffs particularly ice cream and local soft drinks. However, there is little evidence about its rheological properties in the literature. Therefore, in the present study, the influence of variables such as concentration (2–7 g l-1), temperature (5–55°C), pH (2, 4, 6, 7, 9, and 11) as well as rotational speed (up to 200 rpm) were examined on the apparent viscosity and flow behavior of the gum solution. Regarding the effect of the abovementioned parameters, our findings revealed that increasing rotational speed or shear rate at low concentrations (3 and 4 g l-1) had no effect on the apparent viscosity and those samples behaved like Newtonian fluids whereas, at slightly higher concentrations (5–7 g l-1), with increasing the rotational speed, the apparent viscosity diminished and the solution consequently showed a Pseudoplastic behavior. In all these experiments, the apparent viscosity was enhanced with increasing the concentration and diminished with increasing the temperature. In addition, changing the pH showed no significant effect on the apparent viscosity in the majority of samples. Furthermore, using mathematical equations, experimental findings (namely rotational speed and torque) were converted to their fundamental counterparts (shear rate and shear stress) and discussed. 752 General Genetic Variation among Baluchi Sheep Population Using Microsatellite Markers S. Esmail Khanian A. Negati Javaremi F. Afraz P. Daneshyar S. Ghanbari 1 10 2007 11 41 373 380 09 01 2008 In order to identify polymorphic microsatellite markers and evaluae genetic variation within Baluchi sheep population, nineteen microsatellite loci were studied. Whole Blood samples were collected from 156 sheep at north eastern animal breeding station of Iran (Abbasabad-Mashhad). DNA was extracted by salting-out procedure with some modifications. Polymerase chain reactions were successfully done except for UNC5C locus. PCR products were electrophoresed on 8% denaturing polyacrylamide gels stained according to rapid silver staining procedure. The genotype and allelic frequencies were calculated by direct counting and used for estimating of different polymorphism and genetic variation criteria. This population wasn't at Hardy-Weinberg equilibrium except for OarAE101 locus (P<0.005). Heterozygosity (gene variation) ranged from 0.1 to 0.93. BULGE5E and BM1329 loci were monomorphic. In conclusion, this investigation showed high polymorphism at the studied loci, so they could be used in future studies. 753 General Phenotypic and Genetic Changes of Ewe’s Economic Traits in the Lori-Bakhtiari Sheep Stud M. Vatankhah M. A. Talebi M. A. Edris 1 10 2007 11 41 381 391 09 01 2008 In this study 5025 records from the Lori-Bakhtiari sheep stud were used to predict phenotypic, genetic and environmental change in ewe traits from 1989 to 2004. Best linear unbiased prediction (BLUP) of breeding values were estimated by Drivative Free Restricted Maximum Likelihood (DFREML) procedure using single and multi-trait animal model. Phenotypic, genetic and environmental trends were calculated by regressing of the average phenotypic values, predicted breeding values and environmental values in the year of ewe birth respectively. The estimated phenotypic trends were –0.1223 kg for ewe body weight, -0.0415 kg for greasy fleece weight, 0.6639% for conception rate, 0.0003 for number of lambs born per ewe lambing, 0.0094 for number of lambs weaned per ewe lambing, 0.0380 kg for total birth weight per ewe exposed and 0.4227 kg for total weaning weight per ewe exposed. The estimated genetic trends were 0.0603 kg, -0.0004 kg, 0.0183%, -0.0012, -0.0007, 0.0030 kg and 0.0211 kg from single trait analysis and 0.0549 kg, -0.0006 kg, 0.0089%, -0.0008, -0.0008, 0.0030 kg and 0.0230 kg respectively from multi-trait analysis. The estimated phenotypic and environmental trends were significant but genetic trends were not significant (P<0.05) for often traits. 754 General Determination of the Nutritive Value of Three Species of Annual Alfalfa Using in Vitro , in Vivo and Palatability Methods N. Hedaiat Y. Rouzbehan S. A. M. Modares Sanavi 1 10 2007 11 41 393 404 09 01 2008 The nutritive value of the annual alfalfa (Medicago rigidulla, Medicago polymorpha and Medicago scutellata) species harvested at flowering stage was assessed by chemical composition, in vitro dry matter and nitrogen digestibility, in sacco dry matter and nitrogen degradation (0, 8, 12, 24, 48 and 72 h) and palatability (short-term intake rate, STIR) methods. Mean values of the chemical analysis results (%) for M. rigidulla, M. polymorpha and M. scutellata respectively were as follows: OM 85.1, 86.1 and 86.9 CP 25.1, 23.8 and 15.6 NDF 23.2, 24.8 and 30.0 ADF 18.3, 19.9 and 24.0 ADIN 0.36, 0.11 and 0.22 calcium 1.4, 1.3 and 1.2 phosphorus 0.23, 0.28 and 0.24 potassium 1.5, 1.5 and 1.4. The digestibilities of the DM and OM for M. rigidulla were 0.82 and 0.79 M. polymorpha 0.83.5 and 0.80 M. scutellata 0.75 and 0.69, respectively. The degradabilities of DM and CP at outflow rate of 0.05 for M. rigidulla were 0.72 and 0.55 M. polymorpha 0.71 and 0.57 M. scutellata 0.63 and 0.58, respectively. Finally, the palatabilities (using short-term intake rate method) for M. rigidulla, M. polymorpha and M. scutellata species were 13.6, 12.8 and 11.3 (g DM/min) respectively. According to the methods used, the descending ranking order (high to low) of these species on the basis of their nutritional value was M.rigidulla, M.polymorpha and M.scutellata. 755 General Determination of Chemical Composition and Evaluation of Apparent and True Metabolisable Energy of Different Barley Cultivars in Broiler Chicks A.A. Gheisari A.H. Pourabadeh J. Pourreza M. Mahlougi R. Bahadoran 1 10 2007 11 41 405 415 09 01 2008 This study was conducted to determine chemical composition and evaluated apparent metabolisable energy (AME) and true metabolisable energy (TME) values of five Iranian barley cultivars. Basal diet contained corn soybean and in each of the test diets barley was substituted for 30% of corn and soybean fractions. The study was carried out in 3 experiments. In experiment 1, metabolisable energy (ME) values were measured by both total collection and markers (chromic oxide) in excreta of 35-d-old chicks. In experiment 2, ME values of the barley cultivars were determined by ileal digesta procedure. In experiment 3, 36 48-d-old broiler chicks (used in experiment 1 and 2) were used to determine TME and the nitrogen corrected TME (TMEn) of the barley cultivars. Highly significant differences (P<0.05) between bioassay methods were observed on average barley ME values. The average barley AMEn value measured by ileal digesta method was significantly (P<0.05) higher than excreta (total collection and markers in excreta) (2716 Vs. 2318 and 2124 kcal/kg, respectively). Barley ME values were influenced by cultivar (P<0.05) and the hullless cultivar showed greater AME value than the hulled cultivars (2695 vs. 2407.5 kcal/kg AME 2630 vs. 2324.7 kcal/kg AMEn). Cultivar had no significant effect on barley TME value. It was concluded that there is high variation between energy contents of Iranian barley cultivars. In addition, ileal digesta was found not to be an accurate bioassay for determination of barley AME value in broiler chicks. 756 General Investigation and Comparison of Reasons for Farmers Disagreement with Land Consolidation Projects in Kermanshah and Lenjanat Region in Isfahan A. M. Amini A. Ahmadi A. Papzan 1 10 2007 11 41 417 432 09 01 2008 The purpose of this study was to assess characteristics of and reasons for farmers’ disagreement on implementation of land consolidation projects. Part of needed information was collected through questionnaire and interviewing 75 farmers in 6 unsuccessful villages in Kermanshah and Lenjanat region and also visiting some performed and ongoing projects. Other part of information was obtained by questionnaire and interviewing 44 experts involved with performing the project in Jahad Agricultural offices. Fragmentation of properties were measured by Januszewski fragmentation coefficient. Correlation coefficient and comparison of mean were used to analyzed the information. The results showed that disagreement of farmers is the most important obstacle for progress on land consolidatin projects, which accounted for farmers. In Lanjanat, these farmers have a better land structures in respect to size and fragmentation of parcels. In both rejoin reasons for farmer’s disagreement are divided in three groups: logical-justified reasons, logical-unjustified and illogical. Mediation, preference and legislative force are the three interactive methods to satisfy these farmers. To decrease disagreements and promote land consolidation in the two regions, following suggestions are offered: education and extension, correcting the technical and adminestrative methods of land consolidation and legal and judicial supports to implement the projects. 757 General Comparative Analysis of Sustainability in Traditional Livestock Production Systems: The Case of Animal Husbandries in Firouzabad County R. Nikdokht E. Karami M. Ahmadvand 1 10 2007 11 41 433 442 09 01 2008 Sustainability of livestock production systems (LPSs) is of prime importance to the needs of human beings. From a sustainability point of view, an LPS is sustainable when it is environmentally nondestructive, economically viable and socially provides appropriate quality of life for producer and the whole community. Iran LPS is primarily based on traditional production systems. Therefore, an important issue for animal production in this country is the question of sustainability of traditional LPSs.The aim of this paper was to investigate and compare the sustainability of traditional LPSs in Firouzabad County. Three dimensions of sustainability were considered. Survey research was used to reach this purpose. Therefore, 300 livestock producers in “Nomadic”, “Semi-nomadic” and “Village- based” system were interviewed. Respondents were selected by a multi-stage cluster random sampling method. Face validity was confirmed by experts and the questionnaires were subjected to reliability testing using data collected in the pilot study. Findings showed that all three LPSs were unsustainable with regard to social, economical, and technico-environmental dimensions. Comparison of LPSs showed that Village-based LPS was from social dimension relatively sustainable and technically and environmentally unsustainable. While nomadic LPS was from social dimension relatively unsustainable and technically and environmentally sustainable. 758 General Influence of Some Topographic Factors on Distribution of Large-Leaved Lime (Tilia platyphyllos Scop.) in Vaz Forest S. E. Sadati S. F. Emadian H. Jalilvand J. Mokhtari M. Tabari 1 10 2007 11 41 443 452 09 01 2008 The present research was conducted to find the influence of some topographic factors on distribution of large-leaved lime (Tilia platyphyllos Scop.) and its natural regeneration characteristics in "Vaz" forest (northern Iran). After identification of site and preparation of topography map, selective sampling method was carried out for tree inventory in plots. The sample plots were circular in 1000-m2 areas with at least 2-3 dominant lime trees in each. In the plots, altitude, slope gradient, direction, forest storey, tree type and natural regeneration were investigated. Results indicate that in this habitat the average diameter at breast height and height of Tilia platyphyllos is 36.9 cm and 23 m, respectively. Tilia platyphyllos prefers 1200-1400 m altitude, 75-100% slope gradient and northeastern to eastern directions and benefits from denser trees in these environments. It consists of some tree types together with Fagus orientalis, Carpinus betulus and Parrotia persica, whereas the dominant type is Tilia platyphyllos-Fagus orientalis. In most of tree types, lime occurs in the upperstorey. Natural regeneration of lime is often observed as sprout (coppice shoot). 759 General Effect of Deforestation, Grazing exclusion and Rangeland Degradation on Soil Quality Indices in Loess-Derived Landforms of Golestan Province F. Kiani A. Jalalian A. Pashaee H. Khademi 1 10 2007 11 41 453 464 09 01 2008 To investigate the degree of forest degradation and the effect of land use change on selected soil quality attributes in loess-derived landforms, samples were taken from different land uses including forest, rangeland, degradated rangeland and farmland in Pasang watershed located in the Galikesh area of Golestan province (37°16'N, 55°30'E). The annual average temperature and mean precipitation of study area were 15°C and 730 mm respectively. Organic matter, pH, EC, CaCO3 and nutrients (N, P, K) as chemical indicators, hydraulic conductivity, bulk density and porosity as physical indicators and soil respiration as biological indicator were measured. The results showed that the amount of organic matter decreased three percent when it was turned from forest to farmland, and increased two percent from farmland to rangeland. The amount of CaCO3 in surface layer of deforested area was more than in the forest soils. The amount of soil N in forest and soil P and K in rangeland were higher than in other land uses. Bulk density and porosity in forest and MWD in rangeland were higher than in other land uses because of the decrease in organic matter due to farming activities. Soil respiration in forest was highest as compared to in other land uses. Difference of enzymes activities (L-asparaginase and Dehydrogenase) compared to microbial respiration indicates that enzymes activity is related to specific biological processes while soil microbial respiration basically depends on the general activity of soil microbial population. It could be concluded that amount of organic matter, soil N, bulk density, porosity, MWD, soil respiration and enzymes activities are suitable indicators for soil quality evaluation in this area. 761 General A Quantitative Investigation of Natural Regeneration in the Gaps Derived from the First Selective Cut in Meskeli Buxus hyrcana Stand A. Goleij H. Jalilvand M. R. Pormajidian M. Tabari K. Mohammadi Samani 1 10 2007 11 41 465 473 09 01 2008 In order to investigate the success of natural regeneration and to determine the best area for regeneration settlement, 12 gaps with the areas ranging from 50-100, 150-300, and 400-600 m2 and 4 replicates equal elevation level were selected. For measuring frequency, height, and collar diameter of regenerated seedlings, a certain number of 2 m2 subplots were carried out inside the gaps, along the bigger diameter, and related to each gap’s area. Results showed that the number of seedling varies from 5 (in big gaps) up to 28 (in small and moderate gaps) per square meter. Furthermore, there was not a significant difference between the number of seedlings in small and moderate gaps. In contrast, the number of seedlings in small and moderate gaps was significantly different from those in large gaps (at 1% Probability). This finding demonstrates that natural regeneration would be limited in large gaps (400-600 m2) but it shows a better result in smaller gaps, associated with single- tree harvests. The final result of this study shows that the most appropriate area for selective cuting in such an area is up to at most 300 m2.