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      • Open Access Article

        1 - Prediction of Customer Satisfaction level in after-sales service in automotive industry- Dealers in Saipayadak Co.
        Reyhaneh Varasteh Ahmad Ebrahimi
        10.30495/jmfr.2022.19571
        Background: Based on the competition and product variety in the automotive industry, auto makers require to achieve capability to respond properly to customers and their competitors. The special position of after-sales service in automotive industry and also maintain th More
        Background: Based on the competition and product variety in the automotive industry, auto makers require to achieve capability to respond properly to customers and their competitors. The special position of after-sales service in automotive industry and also maintain the existing customers and attract the new ones, makes the prediction and measurement of customer satisfaction as a must in this industry.Purpose: In this paper, using prediction approach in futures studies, has made us firstly to identify the influential factors on customer satisfaction. Then the customer satisfaction level has been predicted and analyzed in after-sales service of dealers in an automotive manufacturer.Methods: The statistical population includes the dealers of Saipayadak Co. The statistical sample includes 14486 of after-sales service dealers in the period of April 2017 to June 2017. Independent variables, after extracting through literature review, were finalized using brainstorming and fishbone diagrams. Statistical analysis and prediction was performed using stepwise regression method with coding in RStudio software.Findings: By using data mining method, the customer satisfaction score in after-sales service of dealers in Saipayadak Co. has been predicted with 80% accuracy.Conclusion: By knowing the customer satisfaction level, auto makers can define quality improvement projects and move toward to competitiveness desirably. Manuscript profile
      • Open Access Article

        2 - Measurement designing and assessing effective factors on municipality's employee job satisfaction
        احسان سپهوند رسول محمدرضایی
        Introduction and Objective: One of the management's issues that are more interest for scientist is optimize human resource management which plays key role of organization's efficiency and one aspect of the optimization human resource management is job satisfaction. The More
        Introduction and Objective: One of the management's issues that are more interest for scientist is optimize human resource management which plays key role of organization's efficiency and one aspect of the optimization human resource management is job satisfaction. The purpose of this research is instrument designing to job satisfaction measurement of stuff by appropriative questioner which consider especial circumstance of Ahwaz municipality worker, then identify and analyze the influence factor on determinate job satisfaction. Methods: In this study to obtain the appropriative questionnaire immoderate and intricate of valid questionnaires were used. So at first, to identify involved factors in explaining the job satisfaction Principal Component analysis were used and the result showed: Support, Justice, Stewardship, nature of work and employment facilities are effective component. After this step, by Stepwise Regression the role of each those components in job satisfaction were predicted. In order to discover job satisfaction diversification between different occupational groups, depend on the require test, analysis of variance, T test were used. Results: Results were showed significant difference between different age group and job experience with Job satisfaction and there were no significant difference in educational level with Job satisfaction. According to the result, work environment and ergonomic, providing credit facility for employer, the manager's attendance to meritocracy and training course were offered. Manuscript profile
      • Open Access Article

        3 - Using satellite imagery and spectral data to estimate the amount of soil organic carbon in central Zagros forests in Khoozestan
        saeede esmizade ahmad landi hamidreza matinfar
        10.22034/jest.2020.35742.4259
        Background & Objective: Soil organic carbon (SOC) is one of the most important components of soil physical and chemical properties that prevented soil decay and destruction. The objective of the present study is the evaluation of SOC changes using the remote sensing More
        Background & Objective: Soil organic carbon (SOC) is one of the most important components of soil physical and chemical properties that prevented soil decay and destruction. The objective of the present study is the evaluation of SOC changes using the remote sensing technique compared with field methods at central Zagros forests in Khoozestan province in Iran over the past 2 decades. Material and Methodology:  The soil samples were collected randomly from the soil surface (0-10 cm depth) to estimate the SOC concentrations in the laboratory. Analysis of digital data by using Operational Land Imager (OLI) of satellite Landsat 8 and Enhanced Thematic Mapper (ETM+) sensor of satellite Landsat 7 images in 2016 (the sampling year) was done to estimate surface organic carbon levels of soil. The main objective was to establish soil organic carbon relation with landsat different bands ratios and also herbal and moisture indexes such as NDVI, SAVI, BSCI, NDMI and NSMI corresponding to the SOC values obtained from soil samples of the forest areas in the central Zagros mountain, and for that purpose these data were evaluated using different linear regression methods. Findings: The best fit model of stepwise regression method showed R2 value of 0.435 for landsat 8 and R2 value of 0.501 for landsat 7 and finally based on these results, evaluation of SOC changes occurred in previous years. Discussion and conclusion: Results show the significant relationship between soil organic carbon and the reflectance in the Visible, Near-Infrared and Short-wave Infrared part of the spectrum.   Manuscript profile
      • Open Access Article

        4 - Investigating the Factors Affecting Drought Management of (Ardakan) Farmers
        Homa Poorhosseini Maryam Omidi Najafabadi seyed jamal farajollah hosseini
        Background and Objective: Drought is an inevitable phenomenon known as a natural disaster. Iran has not been immune to this damage in history. Material and Methodology: The purpose of this study is to identify drought management and thus provide solutions to drought m More
        Background and Objective: Drought is an inevitable phenomenon known as a natural disaster. Iran has not been immune to this damage in history. Material and Methodology: The purpose of this study is to identify drought management and thus provide solutions to drought management. At first, individual, social, economic, educational, technical and policy indicators were surveyed in villages of Ardakan city with the highest drought. The statistical population of this research is Ardakan farmers (N=3130), of which 418 samples were collected by Cochran sampling method for collecting information through a questionnaire. A questionnaire was used to collect the data and for its reliability, the preliminary test was confirmed by completing 30 questionnaires and the Cronbach's alpha coefficient for its different parts was calculated to be between 0.702 and 0.805. Findings: The results of stepwise regression analysis indicate that social and cultural indicators explain 46.1 percent of variance dependent changes (drought management) and have been considered as the most influential indicator in this research. Disscusion and Conclusion: In the field of social and cultural indicators in the direction of drought management, it is suggested that by promoting the culture of using water and using cultural and promotional tools during drought among farmers and also providing conditions for providing better drought management information to the villagers Help manage the drought as best as possible through communication channels. Manuscript profile
      • Open Access Article

        5 - Identification of effective traits on sugar beet (Beta vulgaris L.) root yield under rhizoctonia natural infection condition
        حیدر عزیزی
        In order to identify the effective traits on root yield and also determine the cause and effect of the relationship between them, 20 different sugar beet cultivars in a RCB design with four replications for 11 important quantitative and qualitative traits including root More
        In order to identify the effective traits on root yield and also determine the cause and effect of the relationship between them, 20 different sugar beet cultivars in a RCB design with four replications for 11 important quantitative and qualitative traits including root yield, sugar yield, sugar content, white sugar content, extraction coefficient of sugar, a-amino nitrogen, sodium, potassium, alkalinity and molasses sugar were evaluated. The results of analysis of variance showed that the difference between studied cultivars for amino nitrogen (a-N) all traits were significant at the 0.05 probability level and for other traits was important at the 0.01 probability level. Phenotypic and genotypic coefficients of variation for most traits were high, indicating relatively high variability in studied cultivars for evaluated traits. Correlation coefficients between traits showed that there was the most negative and significant correlation between root yield trait with sugar content (-0.62), whit sugar content (-0.53), alkalinity coefficient (-0.52), potassium (-049), sodium (-0.45) and also molasses sugar content (-049) traits, and the most positive and significant correlation with sugar yield (0.95) and extraction coefficient of sugar (0.58) traits, respectively. In multiple regression analysis by stepwise method, sugar content, amino nitrogen and alkalinity coefficient traits were entered into model, respectively, that explained 82 percent of root yield variations. Based on path analysis results, amino nitrogen (0.35) and white sugar content (-0.31) traits had the most and positive direct effect with root yield and thus , selection based on the mentioned traits can help us achieve high-yielding genotypes. Manuscript profile
      • Open Access Article

        6 - Path analysis of yield and yield components in bean (Phaseolus vulgaris L.) under controlled and BCMV infection conditions
        Mohammad Mojtaba Kamelmanesh Sasan Ghasemi Anita Namayandeh
        In order to study cause and effect of seed yield with some agronomical traits in bean genotypes, two experiments were conducted under field conditions. Twenty five common bean genotypes were sown in 2 separate RCB design with three replications under non-infected and in More
        In order to study cause and effect of seed yield with some agronomical traits in bean genotypes, two experiments were conducted under field conditions. Twenty five common bean genotypes were sown in 2 separate RCB design with three replications under non-infected and infected conditions. First, phenotypic correlation coefficient of traits with each other was counted. At non-infected conditions number of secondary stem, harvest index, reproduction period and under infected conditions number of seeds in plant, number of seeds in pod and harvest index showed significant correlation with seed yield at 0.05 & 0.01 probability levels. Stepwise regression and then path analysis were used to determine the traits that were effective on seed yield. In stepwise regression analysis seed yield was the dependent and other traits were as independent variables. At non-infected conditions number of secondary stem, harvest index and main stem length were entered in regression model respectively and explained 84% of seed yield variations. In this manner, under infected conditions, harvest index, plant weight and number of seeds in pod justified 93% of seed yield variations. On the basis of achieved results, harvest index was introduced as profitable selection index at non-infected and infected conditions. In order to results of path analysis after harvest index at non-infected conditions number of secondary stem and at infected conditions number of seeds in pod were introduced as suitable indices. Manuscript profile
      • Open Access Article

        7 - Stock Option Pricing by Augmented Monte-Carlo Simulation models
        Jalal Seifoddini
        10.22034/amfa.2019.1879290.1297
        Manuscript profile
      • Open Access Article

        8 - Investigation of Morphological- Agronomic Diversity in Some of Tomato Cultivars in Khash Region
        Mansoor Saljooghianpour Mohammad Rasouli
        10.30495/sarj.2021.683252
        Tomatoes have many varieties that differ in traits of plant growth, quality and shape of the fruit and other traits. In order to investigate the morphological variation of some tomato cultivars in Khash region, an experiment was conducted as a randomized complete block More
        Tomatoes have many varieties that differ in traits of plant growth, quality and shape of the fruit and other traits. In order to investigate the morphological variation of some tomato cultivars in Khash region, an experiment was conducted as a randomized complete block design with three replications and ten cultivars including Orabana, Red Claude, Red Top, Red Jerez, Western Red, Sunsild, Rio Grande, Delba F1, Tivi F1 and blankets Pride. At the end of the experiment traits such as number of fruits per plant, average fruit weight, fruit diameter, final yield, biomass, harvest index, fruit juice volume, fruit dry weight, total soluble solids, acidity and vitamin C were evaluated as agronomic traits. Were affected. At the end of the experiment, after multiple analyzes, it was found that Tivi F1 and Delba F1 hybrids and Orabana had the highest yield and were suitable for cultivation in Khash region. Also, cluster analysis showed that among the 10 varieties of 3 varieties in group A, 5 varieties in group B and 2 in group C were placed. This grouping showed that genetic diversity followed a significant pattern, because cultivars with better and more closely related conditions under conditions were similar in the same groups. Based on stepwise regression results, the number of fruits per plant justified 63.09% of the fruit yield per plant changes. After fruit number per plant, average fruit weight and number of days to flowering had the greatest effect on fruit yield per plant. Manuscript profile
      • Open Access Article

        9 - Assess the Regression and Correlation Relationships between the Traits Affecting the Seed Yield of Black Cumin (Nigella sativa L.) Cultivars Affected Different Planting Dates and Combined Nutrition
        Ali Fathinia Shahram Lak Rozbeh Farhodi Mani Mojadam Alireza Shokohfar
        Manuscript profile
      • Open Access Article

        10 - Evaluation of Correlation between Physiological and Morphological Traits with Yield in Hull- less Barley Lines
        M.R. Dadashi A. Noorinia M. Askar Sh. Azizi
        Relationships between grain yield and yield components in some hull-less barley lines were studied in experiment conducted in a randomized complete block design with 4 replications at the Research Station of Agriculture of Gorgan, Iran. During growth season several char More
        Relationships between grain yield and yield components in some hull-less barley lines were studied in experiment conducted in a randomized complete block design with 4 replications at the Research Station of Agriculture of Gorgan, Iran. During growth season several characteristics including plant height spike length, number of spike per m2, biological yield, number of total tillers, number of fertile tillers, number of kernel per spike, number of spikelet per spike, relative water content (RWC), coefficient of membrane stability (CMS), flag leaf area, Na/K ratio, grain yield, 1000 kernel weight and harvest index were measured. Results showed that stepwise multivariate analysis was the best suitable model in evaluating of the yield. Path analysis showed that correlation among characteristics which remained in the model was broken into direct and indirect effects. The results derived from correlation and path analysis indicated that almost 70% of the yield increase was due to the direct effect of 1000 kernel weight. Number of kernel per spike was positively significant and number of fertile tillage was also found to have positive and significant direct effect on yield, but number of fertile tiller indirectly affects by higher 1000 kernel weight. Manuscript profile
      • Open Access Article

        11 - Evaluation of Spring Wheat Recombinant Inbred Lines under Drought Stress
        M. Moghaddaszadeh-Ahrabi M. Moghaddam Vahed S. Aharizad S.A. Mohammadi
        Iran is one of arid and semi-arid regions of the world. Wheat as a strategic agricultural products faces water deficiency in most areas of the country. Therefore, identification of the resistant varieties to drought stress is one of main aims for breeders. To assess eff More
        Iran is one of arid and semi-arid regions of the world. Wheat as a strategic agricultural products faces water deficiency in most areas of the country. Therefore, identification of the resistant varieties to drought stress is one of main aims for breeders. To assess effect of drought stress at heading on 72 spring wheat recombinant inbred lines derived from American Yecora Rojo (high yielder, dwarf and early maturity) as paternal parent and Iranian No. 49 line (tall and late maturiting) as maternal parent cross were studied. The experiment was conducted at the Research Station of the University of Tabriz using a randomized complete block design with two replications during 2009 growing season. Based on the results from combined analysis of variance significant difference was observed among lines for all of traits studied, except for harvest index, grain number per spike and days to heading. There was significant difference between normal and drought stress conditions. Since the interaction between line and conditions was insignificant for all traits, it does therefore, provide the possibility of comparing the lines without regard to irrigation levels. Based on the means of, the traits it was found that the lines 96, 122, 123 and 155 were superior. MP, GMP and STI indices were recognized to be suitable indices to identify superior lines. With respect to these indices, lines 96, 122, 123, 138, 149 and 155 were found superior as compared with remaining lines. Based on stepwise regression analysis of grain yield with other traits, respectively grain number per spike, number of spikes/m2 and 1000 kernel weight were inserted into final model as effective variables on grain yield, which made 81/9 percent of the grain yield variation. Path analysis of grain yield and related traits, based on stepwise regression, demonstrated the significant positive direct effect for grain number per spike, number of spikes/m2 and 1000 kernel weight on grain yield. Cluster analysis, also showed that, lines under study were grouped into two clusters; superior lines for studied traits assigned to group one. Manuscript profile
      • Open Access Article

        12 - Relationship Between Yield and Yield Components of Maize Hybrids under Different Irrigation
        جمیله Seyedzavar M. Norouzi S. Aharizad A. Bandehhagh
        To evaluation the response of some maize hybrids to water deficit stress, a field experiment in 2010 was conducted using a split-plot plan on the basis of complete randomized block design with four replications at the Agricultural Research Station, University of Tabriz More
        To evaluation the response of some maize hybrids to water deficit stress, a field experiment in 2010 was conducted using a split-plot plan on the basis of complete randomized block design with four replications at the Agricultural Research Station, University of Tabriz (Khalatpoushan). Main plots consisted of three different irrigation regimes (non-stress, mid-stress and sever-stress) and sub plots of 14 maize hybrids. Results showed significant differences among hybrids and irrigation regimes for all traits studied. Analysis of variance revealed significant differences among hybrids and also irrigation levels for all traits except ear diameter. The best model for stepwise regression based on all traits at the average of conditions, indicated that four responsible traits like number of rows per ear, 300-grain weight, number of grains per row and number of leaves per plant remained in model, which justified 83 percent of the total variations in yield performance. The path analysis showed that the number of rows per ear had the highest direct effect on yield. Based on principal component analysis the first component had a major factor on the weight of 300 seeds, plant height, ear length, flag leaf area, ear diameter and corn cob diameter and the second component had a big factor on plant dry weight, number of kernels per row, number of leaves per plant, number of rows per ear and grain yield. Principal component analysis (PCA), based on all of traits studied determined two principal components that could justify the 78 percent of vaiations. In this research the first component named as the growth-morphological factor and second component named as the yield factor. Manuscript profile
      • Open Access Article

        13 - Survey of Adaptation of Thirty Rice (Oryza sativa L.) Genotypes to West Guilan Climatic Conditions-Astara
        F. Saied zadeh
        Adaptation of thirty rice genotypes was studied in a completely randomized block design experiment with 3 replications for two cropping seasons (2005-2006) in Astara. Analysis of variance showed that differences among the years for the most of traits were not significan More
        Adaptation of thirty rice genotypes was studied in a completely randomized block design experiment with 3 replications for two cropping seasons (2005-2006) in Astara. Analysis of variance showed that differences among the years for the most of traits were not significant where as there was a significant difference among the genotypes and genotype by year interaction. Correlation coefficient of the traits under study showed that grain yield had a positive and significant correlation with number of tiller per plant, paddy yield and harvest index. Stepwise regression analysis revealed that the paddy yield per plant and panicle length had a positive and significant effect on the grain yield. Cluster analysis of genotypes in these grouped genotypes into three categories. Two years of experiment showed these lines producing higher yields, were better adapted to Nemat, line 338, Sangtaroom, Dorfak, Mehr and line 6 fell into the second group.  Manuscript profile
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        14 - Determination of Some Effective Traits on Corn (Zea mays L.) Yield by Using Biofertilizer under Water Deficit Stress Conditions
        M. Hosseini A. Roozbahani امین Azadi
        To identify the most effective traits on corn yield by using biofertilizer under water deficit stress, an experiment was carried out in split plot based on randomized complete block design with three replications in Hashtgerd region in 2012. In this experiment, water More
        To identify the most effective traits on corn yield by using biofertilizer under water deficit stress, an experiment was carried out in split plot based on randomized complete block design with three replications in Hashtgerd region in 2012. In this experiment, water deficit stress, as the main factor, consisted of four levels (control, stress at flowering, stress at grain filling and stress at both flowering and grain filling stages). Biological fertilizers as sub-plot consisted of four levels of biological fertilizer applications (control, application of Nytrazhyn, application of Barvar 2 fertile and application of both fertilizer Nytrazhyn and Barvar 2). Traits evaluated were seed yield, harvest index, 100 seed weight, number of ears per square meter, number of rows per ear, number of seed per row, weight, diameter and length of seeds. To determine the most effective traits simple correlation, stepwise regression analysis, path analysis and principal component analysis were performed. Multivariate analysis showed that harvest index, 100 grain weight and number of ears per square meter were highly effective on grain yield. They explained 77% and 66% of the total variance under both normal and drought stress conditions respectivly. The highest direct positive effect was related to harvest index under both conditions. To improving seed yielding potential of corn under water deficite cinditions emphasis should be placed mainly on the selection of genotypes with higher harvest indices. Manuscript profile
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        15 - Using Wheat Chromosomal Substitution Lines to Study Relationship between Yield and its Components under Water-Stress and Non-Stress Conditions
        Masoud Golestani Shahram Mohammady
        To evaluate relationship between grain yield and its components, two series of wheat`s substitution lines including substitution lines of ‘Timstein’ into genetic background of ‘Chinese Spring’ and ‘Red Egyptian’ into genetic backgroun More
        To evaluate relationship between grain yield and its components, two series of wheat`s substitution lines including substitution lines of ‘Timstein’ into genetic background of ‘Chinese Spring’ and ‘Red Egyptian’ into genetic background of ‘Chinese Spring’ and their parents were tested in a randomized complete block design with four replications under water-stress and non-stress conditions in a greenhouse in 2014. Stepwise regression analyses showed that yield components contributions for seed yield variation were not similar under water-stress and non-stress conditions. So that, under non-stress condition biological yield and harvest index and under water-stress condition the number of seeds per spike and number of spikes explained a higher percentage of variations for grain yield. Biological yield and harvest index were entered into model in three cases out of four regression analyses (two substitution lines series and two conditions) and thus it was deduced that these two traits are the most stable traits in explaining the variations observed for seed yield.Path coefficient analysis showed that biological yield and harvest index had direct and equal effects on seed yield at non-stress condition for two substitution line series. The highest direct effects on seed yield under stress condition for ‘Timstein’ substitution line series belonged to biological yield and harvest index and for ‘Red Egyptian’ substitution lines belonged to the number of seeds per spike and number of spikes. Cluster analysis, based on Ward method and by using Euclidian distance, classified two substitution line series under water-stress and non-stress conditions in three groups. Manuscript profile
      • Open Access Article

        16 - Response of Late Maturing Hybrids Seed Corn to the Application of Potassium Sulfate under Deficit Irrigation
        Zohreh Henteh Henteh Roghayeh Aminian
        To study the effect of potassium sulfate on seed yield, yield components and traits affecting seed yield of late maturing corn, a split split plot experiment using a randomized complete block design with three replications was carried out in Kashan Desert Research Stati More
        To study the effect of potassium sulfate on seed yield, yield components and traits affecting seed yield of late maturing corn, a split split plot experiment using a randomized complete block design with three replications was carried out in Kashan Desert Research Station. Irrigation levels consisted of complete irrigation and cutting off irrigation at panicle emergence and seed filling stages which were considered as the main factor, three levels of potassium sulfate 200 (recommendation based on the soil analysis), 245 and 290 kg.ha-1 as the subplot, and two single cross of corn, KSC 700 and 704, as sub-sub plots. Effect of irrigation on traits like seed number per row, 1000 seed weight, biological yield, relative water content and relative water loss were significant. The effect of cultivar on all traits, except relative water loss, and the effect of fertilizer on all traits, except number of rows per ear, were also significant. All of the KSC700 traits, except plant highest were better than those of cultivar KSC704. The highest values for the most traits were obtained in full irrigation condition, applying potassium sulfate at the rate of 290 kg.ha-1 for KSC 700. Cutting off irrigation at the panicle emergence of KSC 900 and seed filling of KSC 704 did not cause significant reduction in seed yield. Highest correlation of grain yield were obtained with number of kernels per row, 1000 grain weight and harvest index. Stepwise regression results showed that number of rows per ear, number of kernels per row and 1000 grain weight in KSC 700, and biological yield and harvest index in KSC 704 justified 98.7 and 98.5 percent of changes, respectively. Manuscript profile
      • Open Access Article

        17 - Evaluating the Relationships among Traits in Thyme (Thymus daenensis subsp. Daenensis) Ecotypes under Non-Stress and Drought Stress Conditions
        Masoud Golestani
        10.30495/jcep.2020.671171
        To study the relationships among traits of thyme ecotypes, two experiments under non-stress and drought stress conditions were carried out using randomized complete block design with four replications in Abarkouh during 2017-2018 cropping season. Correlation analysis wa More
        To study the relationships among traits of thyme ecotypes, two experiments under non-stress and drought stress conditions were carried out using randomized complete block design with four replications in Abarkouh during 2017-2018 cropping season. Correlation analysis was used for evaluation of relationships among traits. Stepwise regression and path analysis were used for determination of effective traits on shoot dry weight and for determination of direct and indirect effects on shoot dry weight, respectively. Factor analysis was used for identifying factors that produce special correlations among measured variables. Correlation coefficients among traits showed that there were significant positive correlation among traits like shoot fresh and dry weight with maximum and minimum diameter of canopy, canopy area, leaf length, number of stems per plant and essential oil yield under both conditions. The result of stepwise regression showed that canopy area, leaf width, leaf length, number of flower in inflorescence and number of days to 50% of flowering under non-stress condition and canopy area, leaf width, leaf length and number of days to 50% of flowering under stress condition were entered to the stepwise regression model. The result of path analysis under both conditions showed that canopy area had the highest direct and positive effect on shoot dry weight and leaf width and negative effect on shoot dry weight. Based on factor analysis, three factors were selected and these factors explained 76% of total variation under both conditions and traits such as shoot fresh and dry weight, maximum and minimum diameter of canopy, canopy area, leaf length, number of stems per plant and essential oil yield were main components of these factors. Manuscript profile
      • Open Access Article

        18 - Correlation and Path Analysis of Yield and Yield Components of Safflower Genotypes under Late Season Drought Stress Conditions
        Seyedeh Zahra Hosseini
        To calculate correlation coefficients and path analysis of some traits related to grain yield, 15 genotypes of safflower were studied under non-stress and drought stress conditions at two different sites (with 10 meter distance) in the field of College of Agriculture of More
        To calculate correlation coefficients and path analysis of some traits related to grain yield, 15 genotypes of safflower were studied under non-stress and drought stress conditions at two different sites (with 10 meter distance) in the field of College of Agriculture of Lorestan University, Iran. Each experiment was conducted in a randomized complete block design with three replications. Analysis of variance showed that there were significant differences among the genotypes for all measured traits and yield in both stress and non- stress conditions. By using stepwise regression, best model was estimated for the two conditions. Sequential path analysis of the correlation between grain yield and other traits showed that days to start flowering, 1000-seed weight and stem diameter had direct effects on grain yield under non-stress conditions, while under drought conditions, seed weight per plant and 1000-seed weight had direct and positive effects on grain yield. Thus, to obtain high yielding varieties of safflower under drought stress condition, we showed attempt to select varieties with high seed weight per plant. Manuscript profile
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        19 - Relationships of Phenology and Physiological Traits with the Yield of Rapeseed (Brassica napus L.) in Northern Khorasan
        Abbas Frooghi Abbas Biyabani Ali Rahemi Karizaki Gorbanali Rassam
        To investigate relationships among physiological traits of 20 rapeseed cultivars, an experiment was conducted at the Research Farm of Agricultural Faculty of Shirvan in Northern Khorasan in Iran, in 2014-2015. The experiment used was a randomized complete block design w More
        To investigate relationships among physiological traits of 20 rapeseed cultivars, an experiment was conducted at the Research Farm of Agricultural Faculty of Shirvan in Northern Khorasan in Iran, in 2014-2015. The experiment used was a randomized complete block design with four replications. Results showed that there were significant differences among cultivars for seed and biological yield, the number of pod/plant and seed/pod, 1000 seed weight, harvest index, days to germination, seedling, rosette, shooting, flowering time, end of flowering, pod formation time, end of pod formation, seed filling time and physiological maturity among the traits of rapeseed under study. The highest yield belonged to Traviata (513.56 g/m2) but did not have significant difference with Kodiak, Bilbao, L72 and SW102. The lowest yield belonged to Shirali cultivar (344.41 g.m-2) but it also did not have significant difference with Zarfam and Sarigol cultivars. Positive and significant correlation was observed for seed and biological yields, number of pods/plant and seeds/pod, seed weight, harvest index, the number of days to flowering, flowering end, beginning pod formation, ending pod formation, beginning seed filling, plant height and seed filling rate, but correlations were negative between seed yield and seed filling period and day to emergence and rosette. According to stepwise regression, seed yield was considered as dependent variable and other traits as independent ones. Positive direct effects of harvest index and biological yield and also positive indirect effect of biological yield on number of pod/plant and positive indirect effect number of pod/plant on harvest index were the traits that can be used for selection of high yielding genotypes. Path analysis revealed that traits like seed weight and seed number per unit, seed number and seed weight are its determiners of seed yield. The results also showed that seed filling rate is more effect than seed filling period in determination of seed weight. Regression analysis also showed that by increasing temperature, seed filling period was decreased by 1.54 days and seed filling rate increased 0.004 mg/grain.day-1 centigrad-1. Based on these results it could be concluded that genotypes varied significantly for the rate and duration of seed filling.  Manuscript profile
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        20 - The role of spatial and temporal fluctuations of climatic parameters in dry land wheat yield (Case study: Kaleibar and Khodaafarin County)
        Maseood Jalali Gholam Hasan Mohammadi Atefeh Hoseini Sadr Hosein Khoshvaghti4
        Recognition of climate and doing research about climatic requirements of farm plants can be regarded as main factors in the production process. According to the importance of the climatic fluctuations in rainfed productions, in this study effect of spatial distribution More
        Recognition of climate and doing research about climatic requirements of farm plants can be regarded as main factors in the production process. According to the importance of the climatic fluctuations in rainfed productions, in this study effect of spatial distribution and temporal variation of climatic elements on wheat yield was studied in dry land farms of Kaleibar and Khodaafarin counties. For this, distribution of precipitation parameters was mapped in GIS environment and year-to-year variety of temperature and rainfall analyzed by drawing of charts. And thus with using wheat growing requirements (including desired climatic conditions), ability to meet the climatic needs of this valuable plant were examined. In addition by running of stepwise multivariate regression model between 16 meteorological parameters and average wheat yield, the role of climatic fluctuations in dry land wheat yield identified and the best predictive model determined. Final results of this study show the fact that the importance of each of temperature and precipitation factors differ according to different phonologic stages of wheat at the study region. Although it seems that the mean annual rainfall in study area appears desirable but large fluctuation from year to year as well as small amount of rain in Khordad(June) are the main limitations of rain fed wheat cultivation. Temperature in germination and grain filling stages are created ideal condition but at the flowering stage temperatures are cooler than optimal physiological threshold. The stepwise regression presented a model with 7 meteorological parameters that can be explain a significant impact of climate parameters on dry land farming wheat yield at 95% confidence level on the study region. Manuscript profile
      • Open Access Article

        21 - Determination of the most important traits affecting the electrolyte leakage of wild pear (Pyrus biossieriana Buhse) under drought stress conditions using multivariate statistical methods
        seyed morteza zahedi Mahdieh Karimi Farzad Kian Ersi
        Wild pears are an important rootstock for different pear cultivars and considering it is nearly tolerant to drought stress it is necessary to use different treatments to increase its tolerance to drought stress. Electrolytes leakage is an important and effective factor More
        Wild pears are an important rootstock for different pear cultivars and considering it is nearly tolerant to drought stress it is necessary to use different treatments to increase its tolerance to drought stress. Electrolytes leakage is an important and effective factor in response to drought stress and related traits. For this purpose, a factorial experiment was designed in a randomized complete blocks design with three replications to identify the traits affecting electrolytes leakage. These traits were studied in 12 treatments including different levels of drought stress and different concentrations of brassinosteroids on wild pears in spring and summer of 2017 in greenhouse conditions. The result showed a positive significant correlation between proline content (0.83**), malondialdehyde (0.98**), hydrogen peroxide and electrolyte leakage. The correlation for dry weight of root, leaf and stem, height growth, chlorophyll a, b and carotenoid was significantly negative. Stepwise regression analysis indicated that chlorophyll a, leaf dry weight, height growth and hydrogen peroxide were the most important effective traits on electrolytes leakage and showed 99% of total variance. Based on the path analysis results, the traits of electrolytes leakage and height growth and chlorophyll a showed the maximum positive direct and significant at p Manuscript profile
      • Open Access Article

        22 - Investigating agrotechnological features affecting sugar yield of Beta vulgaris L. in different planting dates for cultivar selection in northwest of Iran
        Esmail Nabizadeh Farhang Movloudi Heydar Azizi
        10.30495/iper.2022.690228
        In order to identify the agrotechnological features on sugar yield and determine the cause and effect relationships between them, 13 different domestic and foreign monogerm varieties of sugar beet were evaluated in a completely randomized design with four replications i More
        In order to identify the agrotechnological features on sugar yield and determine the cause and effect relationships between them, 13 different domestic and foreign monogerm varieties of sugar beet were evaluated in a completely randomized design with four replications in terms of 11 important quantitative and qualitative traits in the station Miandoab Agricultural Research Station during three different harvest dates (October 15, October 30, and November 15) in the crop year 2017. The results of analysis of variance showed that the differences between the studied cultivars in terms of all evaluated traits were significant at p≤0.01. Phenotypic and genotypic diversity coefficients were high for most of the traits, which indicates relatively high diversity in the studied cultivars for the evaluated traits. The genetic correlation coefficients between the traits showed that the highest positive and significant correlation was between the sugar yield trait and the pure sugar yield traits (0.88), gross sugar percentage (0.71), and pure sugar percentage (0.65) in this order while there was a negative and significant correlation between the sugar yield trait and the traits of molasses sugar content (-0.62), alkalinity coefficient (-0.58), and root potassium content (-0.52). In the step-by-step multiple regression analysis, sugar percentage traits, gross sugar percentage, harmful nitrogen content and root yield were entered into the regression model in that order, which justified 84% of the total sugar yield. Based on the results of causality analysis, the traits of gross sugar percentage (1.12) and root yield (1.03) respectively had the most direct effect on sugar yield, so selection based on these traits can help us achieve the genotypes with high sugar yields.  Manuscript profile
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        23 - کاربرد مدل‌های ریاضی برای تخمین میزان انرژی قابل متابولیسم اقلام خوراکی انرژی‌زا در طیور
        M. Sedghi K. Tayebipoor B. Poursina M. Eman Toosi P. Soleimani Roudi
        این مطالعه با هدف بررسی امکان پیش‌بینی انرژی قابل متابولیسم ظاهری (AME) در طیور با استفاده از آنالیز تقریبی در نمونه‌های گندم (51 نمونه)، جو (56 نمونه) و یولاف (34 نمونه) انجام شد. از آنالیز رگرسیون گام به گام برای ارزیابی رابطه بین AME با نشاسته، عصاره اتری (EE)، فیبر More
        این مطالعه با هدف بررسی امکان پیش‌بینی انرژی قابل متابولیسم ظاهری (AME) در طیور با استفاده از آنالیز تقریبی در نمونه‌های گندم (51 نمونه)، جو (56 نمونه) و یولاف (34 نمونه) انجام شد. از آنالیز رگرسیون گام به گام برای ارزیابی رابطه بین AME با نشاسته، عصاره اتری (EE)، فیبر خام (CF)، قندهای محلول (SS)، خاکستر (ash) و پروتئین خام (CP) در نمونه‌های گندم و جو، و ماده خشک (DM) ، CF، Ash و CP در نمونه‌های یولاف استفاده شد. براساس نتایج رگرسیون گام به گام، SS، CF و Ash، بهترین متغیرهای ورودی برای پیش‌بینی AME در نمونه‌های گندم بودند. بعلاوه، نشاسته،CF  و EE در نمونه های جو و CF و CP در نمونه‌های یولاف بهترین پارامترهای ورودی جهت تخمین AME شناسایی شدند. همچنین برای بدست آوردن بهترین مدل تخمین زننده AME در این غلات با استفاده از ورودی‌های انتخاب شده از رگرسیون خطی چندگانه (MLR) و شبکه عصبی مصنوعی (ANN) استفاده شد. نتایج MLR و ANN نیز نشان داد که SS، CF و ash فاکتورهای مؤثری جهت تخمین AME درگندم می‌باشند. برای پیش‌بینی AME نمونه‌های جو CF، EE و نشاسته متغییرهای مستقل خوبی به شمار می‌آیند. همچنین CF و CP پارامترهای خوبی برای پیش‌بینی AME در نمونه‌های یولاف می‌باشند. در ارتباط با کارایی مدل‌ها، دقت مدل ANN بالاتر از مدل MLR بود. بر اساس این نتایج، می‌توان چنین نتیجه‌گیری کرد که استفاده از ترکیبات شیمیایی موجود در نمونه‌های گندم، جو و یولاف، همراه با مدل ANN، روش کاربردی جهت پیش‌بینی AME این غلات در تغذیه طیور می‌باشد. Manuscript profile
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        24 - Selection of drought-tolerant and drought-sensitive lines (Glycine max) using PCA
        Mohammad Hassanvand Mahdi Changizi Shahab Khaghani Masoud Gomarian Ezatollah Sedaghatfar
        10.30495/ijpp.2021.1929834.1326
        Manuscript profile
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        25 - Leadership style and job satisfaction:the comparison of steowise regression with ridge regression
        Hamid R. Oreizie Mohsen Golparvar
        This research compared the usage of stepwise and ridge regression models in the field of industrial psychology when independent variables are correlated. Three hundred twenty nine randomly chosen industrial men personnels of Isfahan completed the Manager’s Leaders More
        This research compared the usage of stepwise and ridge regression models in the field of industrial psychology when independent variables are correlated. Three hundred twenty nine randomly chosen industrial men personnels of Isfahan completed the Manager’s Leadership Style Questionnaire (Gerstner & Day, 1994) and the Job Satisfacation Questionnaire (Brayfield & Rothe, 1951). According to the results of stepwise regression analysis, the managers’ emphasis on the “grievance investigation” was the only factor that predicted job satisfaction among personnels (= 0.84, P<0.05). However, the results of ridge regrssion analysis demonstrated that besides grievance investigation, learning significance and perceived organizational justice also predicted job satisfaction (respectively =0.6, P<0.05; =0.2, P<0.05; =0.2, P<0.01). Although the explained vairance based on stepwise regression (R2 =0.7) is more than that based on the ridge regression (R2 =0.6), the results derived from this method seems to be more realistic because of accounting the multiple collinearity. Manuscript profile
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        26 - Estimating Plant Biomass by Using Non-Destructive Parameters in Arid Regions (Case Study: Inche-Broun Winter Rangelands, Golestan, Iran)
        Naghmeh Gholami Baghi Adel Sepehri Hossein Barani Salman Abdol-Rasoul Mahini
        Manuscript profile
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        27 - Designing and Explaining the Systematic Risk Estimation Model using metaheuristic Method in Tehran Stock Exchange: Adaptive Approach to the Model of Econometrics and Artificial Intelligence
        Nemat Rastgoo hosein panahian
        Systematic risk is always one of the most important indicators that investors and financial analysts attach importance in their financial decision making. The purpose of this research is to provide a new model based on accounting variables for estimating the systematic More
        Systematic risk is always one of the most important indicators that investors and financial analysts attach importance in their financial decision making. The purpose of this research is to provide a new model based on accounting variables for estimating the systematic risk index (β). The period of study is from 2006 to 2015. The statistical population of the research is the companies accepted in Tehran Stock Exchange. Using the Cochran formula, 174 companies are selected as the research sample. For this purpose, systematic risk beta is first calculated through ARFIMA-FIGARCH, and then, estimated models are compared using stepwise regression econometrics (forward selection) and artificial intelligence (through combination of genetic algorithms and flying birds algorithms in selecting effective factors and its modeling by combining and implementing an evolutionary dynamic data estimator algorithm on the above algorithms). In order to analyze the data, three software of Oxmetrics, Eviews, and MATLAB are used. The prediction accuracy of two models based on econometrics and artificial intelligence is evaluated by calculating the correlation coefficient between estimated betas and beta of ARFIMA-FIGARCH. The AI-based model with a correlation coefficient of 94 percent shows a higher predictive accuracy.   Manuscript profile
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        28 - Explaining the Optimal Model of Appraisal and Pricing of the Initial Pablic Offering using Fuzzy Multi-Criteria Decision Making Techniques, Multivariate Regression, Neural Network and Genetic Algorithm
        samaneh fathalian sayyed Ali Nabavi Chashmi Ebrahim Chirani
        Valuation and pricing of securities the process of estimating the value of securities is one of the initial shares of companies. Because, on the one hand, investors need to know in a conscious investment that knows the true value of the stock they are interested in inve More
        Valuation and pricing of securities the process of estimating the value of securities is one of the initial shares of companies. Because, on the one hand, investors need to know in a conscious investment that knows the true value of the stock they are interested in investing in and on the other hand, the owners of companies that are going to sell their securities have to evaluate and value their assets in a proper manner. Therefore, the purpose of this study is to explain the optimal model of evaluation and pricing of the initial public supply of shares of companies accepted in Tehran Stock Exchange using fuzzy multi-criteria decision-making techniques, stepwise regression, neural network and genetic algorithm. To this end, data on 421 companies were collected that during the years 2006 to 2018 launched a public offering of shares on the Tehran Stock Exchange. Fuzzy AHP method, forward regression, neural network and genetic algorithm are also used to analyze the data. The results of the research showed that the genetic algorithm model is the optimal pricing model and initial stock valuation. Manuscript profile
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        29 - Prediction of Wheat Biological Yield Using Geostatistics (Northern Darab)
        abdollah setoodeh marzieh mokarram vahid barati
        The aim of the study is determination of the correlation between factors affecting in the wheat yield and preparing of yield mapping of wheat in north of Darab city. In order to determine the relationship between biological and grain yield with some of the important agr More
        The aim of the study is determination of the correlation between factors affecting in the wheat yield and preparing of yield mapping of wheat in north of Darab city. In order to determine the relationship between biological and grain yield with some of the important agronomic traits 60 samples in the north of Darab city was investigated. Parameters such as plant height, seed weight, harvest index, tiller number, latitude and longitude for each of the samples was measured. The results show that grain weight has highest correlation with the biological yield (0.97**). In this study, also using the Kriging (Gaussian models, spherical, circular and exponential models) and average inverse distance (IDW) maps of the biological yield and grain weight was determined. The results of the interpolation show that kriging method (Gaussian model) with a minimum error (RMSE=0.98 for biologic yield and RMSE=0.97 for grain weight) was the best model for preparation of these parameters in the study area. Also the results of biologic yield map show that areas locating in the North West of the study area were the highest yield. Manuscript profile
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        30 - Factor analysis genetic correlation and path analysis of different traits in durum wheat genotypes
        Hadis Heidarinejad Ahmad Ismaili Tahmaseb Hosseinpour Hamidreza Eisvand
        In order to investigate the path analysis of effective traits on durum wheat yield, an experiment was conducted based on randomized complete block design with 18 genotypes and four replications in Agricultural and Natural Resources Research Center of Lorestan province d More
        In order to investigate the path analysis of effective traits on durum wheat yield, an experiment was conducted based on randomized complete block design with 18 genotypes and four replications in Agricultural and Natural Resources Research Center of Lorestan province during 2014–2015. In Factor analysis, the first factor was named as influencing factor on flag leaf characteristics, the second factor was named as influencing factor on height, and the third factor was named as influencing factors on yield performance. According to results of genetic correlations, biomass yield, straw yield, kernel per spike and spike length had very strong positive correlation with grain yield. According to results of stepwise regression and path analysis, straw yield, kernel per spike and peduncle length entered to the regression model, and so the straw yield had highest and largest direct effect on grain yield. As kernel per spike and straw yield were more important, these traits could be advisable in breeding programs of durum wheat. In present research, bi-plot analysis was used to simultaneous study of traits and discrimination of genotypes related to these traits, and hence, genotypes of Dehdasht, Seimareh, Pod-20 and Alas were introduced as hopefull genotypes for future breeding programs. Manuscript profile
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        31 - Investigation of correlation and causal relationships affecting yield of 14 cotton genotypes in normal conditions and imposing drought stress after flowering
        saman sedigh Mohammad zabed M.Gh Ghaderi A. Samadzadeh
        The purpose of this study was to identify the most important traits affecting yield in 14 cotton genotypes in normal conditions and imposing drought after flowering. Two separate experiments were conducted in a randomized complete blocks design with three replicates at More
        The purpose of this study was to identify the most important traits affecting yield in 14 cotton genotypes in normal conditions and imposing drought after flowering. Two separate experiments were conducted in a randomized complete blocks design with three replicates at the Agriculture Research Farm, University of Birjand during 2013. Phenotypic correlation analysis showed that the correlation between cotton yield with fiber weight, biological yield, harvest index, 1000-seed weight, number of bolls per plant, days to second harvest, oil percent in normal conditions and with fiber weight, biological yield, harvest index, 1000-seed weight and number of bolls per plant in stress condition was positively significant. The stepwise regression analysis showed that the boll number per plant and fiber weight was the most important traits that affected the cotton yield in normal and stress conditions, respectively. The path analysis showed that the fiber weight and biological yield in normal and the biological yield and harvest index in stress conditions had the greatest positive impact on cotton yield. For two conditions the genotypes were grouped into five classes by cluster analysis. Factor analysis was detected that five factors in normal conditions and four factors in stress conditions, showed % 90.03 and % 81.28 of total of variations. In normal and stress conditions yield factor selected as the first and secend important factors, respectively. Manuscript profile
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        32 - Assessment the relationship between grain yield and agronomic traits of spring wheat genotypes in dry land condition
        ali ahmadi R. Porghasemi T. Hosseinpor S. Sohrabi
        To investigate the relationship between agronomic characteristics with 18 spring wheat genotypes, an experiment was carried out in a randomized complete block design indry land condition of Agriculture and Natural Resources Research Station in Khorramabad during 2011-20 More
        To investigate the relationship between agronomic characteristics with 18 spring wheat genotypes, an experiment was carried out in a randomized complete block design indry land condition of Agriculture and Natural Resources Research Station in Khorramabad during 2011-2012. Fourteen traits including seed yield and their components and morphological characteristics were evaluated. Correlation analysis showed that biomass has the highest positive and significant correlation coefficient (r= 0.79**) with yield. And then straw yield, harvest index and spike r = 0.56*, r = 0.50* and r = 0.49* respectively. Based on stepwise regression spike, harvest index, weight and height of the main spike yield components and grain yield were greater share of justification. Path analysis showed that the number of spike per square meter, harvest index, spike weight and height were important factors in increasing yield. The highest positive direct effects on grain yield were also related to the number of spikes and spike weight. Factor analysis showed that four factors (yield, biological yield, straw yield and seed weight) and independent of the total 72% of total variance explained data. The first factor is the factor with the greatest variance function against three traits of effective biological yield, straw yield and grain weight on grain yield confirmed. Manuscript profile
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        33 - Determination the most suitable effective traits on grain yield of bread wheat genotypes under normal and drought conditions in Darab region, Fars Province
        Vahid Barati Ehsan Bijanzadeh Ruhollah Naderi
        Drought stress is the most limiting factor for producing wheat grain yield, especially in southern Iran. In order to recognize the most influential appropriate agronomic traits on grain yield of promising wheat genotypes (16 line) under normal irrigation and drought str More
        Drought stress is the most limiting factor for producing wheat grain yield, especially in southern Iran. In order to recognize the most influential appropriate agronomic traits on grain yield of promising wheat genotypes (16 line) under normal irrigation and drought stress conditions, this study was conducted at Darab, Fars province in 2012-2013 and 2013-2014. Drought stress was started after anthesis and continued to physiological maturity. Days to physiological maturity was counted during growing seasons. At the end of growing seasons, 1000-kernal weight, grain no. per spike, spikelet no. per spike, floret no. per spikelet, tiller no. per unit area, crop height, grain yield, above ground biological yield (BY) and harvest index (HI) were measured. Four statistical methods including simple correlation, multiple linear regression, stepwise regression and path analysis were used for determined the relationship between the above mentioned traits and grain yield under the two irrigation treatments. Results showed that BY and HI for normal irrigation and for drought condition days to physiological maturity, BY and HI were the most important influential traits on yield. Based on the most statistical analysis, the BY role on grain yield was lower at drought condition than normal irrigation. Also, improving grain yield was attributed to HI under drought condition. Manuscript profile
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        34 - Evaluation of relationship between grain yield and yield components in bread wheat cultivars using multivariate statistical methods
        Hossein Ali Fallahi atefeh kaviani charati
        In order to investigate relationship between yield and its components in bread wheat, tested during 2011-2012 were conducted in Agricultural Research Station of Gonbadin randomized complete block design with three replications whit 10 bread wheat genotype (Morvarid, N-8 More
        In order to investigate relationship between yield and its components in bread wheat, tested during 2011-2012 were conducted in Agricultural Research Station of Gonbadin randomized complete block design with three replications whit 10 bread wheat genotype (Morvarid, N-87-4, N-87-9, N-86-6, N-86-8, N-80-19, N-86-5, N-85-5, Kohdasht, Line 17). In this experiment, were measured 7 morphological traits. Analysis of variance genotypes for all traits was significant at 1% probability level. N-85-5 and Line 17 genotypes produced the highest and the lowest grain yield, respectively. Among all tested traits, the number of fertile spike had the highest correlation (0.999 **) with grain yield. Using stepwise regression, the number of fertile spikes entered the model as an effective attribute, justifying 99.8 percent of the data variation. In order to find the causal relationships, the path analysis was performed for grain yield The direct effect on the grain yield was related to the number of fertile spike traits. The results of cluster analysis by ward method showed that the studied cultivars were classified in two groups and the second group in terms of grain yield was the most (397.66). According to the results, can be said that N-85-5 genotype had the highest grain yield and trait number of fertile spike was identified as an effective trait for increasing grain yield. Manuscript profile
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        35 - Relationship among traits and path analysis for grain yield of winter wheat cultivars under normal and drought stress conditions
        azam zarebayati manoochehr khodarahmi khodadad mostafavi
        The usefulness of any corrective program is determined by the relationship between the grain yield and the factors affecting it. For this purpose, 25 winter wheat cultivars were planted and evaluated in a randomized complete block design with three replications in a fie More
        The usefulness of any corrective program is determined by the relationship between the grain yield and the factors affecting it. For this purpose, 25 winter wheat cultivars were planted and evaluated in a randomized complete block design with three replications in a field experiment at the Faculty of Agriculture, Karaj Azad University, Karaj, Iran under two irrigation conditions (normal irrigation and irrigation after the spike stage). 17 traits were measured and evaluated. Simple correlation coefficients of traits indicated a positive and significant correlation between grain yield and days to flowering, biological yield and harvest index in normal conditions, and traits related to rooting, biological yield, harvest index and peduncle outflow length in drought stress conditions. The results of stepwise regression confirmed the relation between grain yield and biological yield., path analysis was performed for the traits introduced in the stepwise regression model and in both normal and stress conditions the most direct effect on grain yield had belonged to biological yield. Manuscript profile
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        36 - Study of genetic variation in safflower genotypes (Carthamus tinctorius L.) in terms of some morphological and agronomic traits
        Ali Khomari Saeed Omrani Ali Omrani Khodadad Mostafavi
        In this study, 32 safflower genotypes in a randomized complete block design with three replications at the Research Farm of Islamic Azad University, Karaj Branch. Plant yield, 1000-seed weight, number of branches, number of bolls per plant, boll weight, flowering time, More
        In this study, 32 safflower genotypes in a randomized complete block design with three replications at the Research Farm of Islamic Azad University, Karaj Branch. Plant yield, 1000-seed weight, number of branches, number of bolls per plant, boll weight, flowering time, seedling time, plant height and flowering time were measured and recorded. Results and Discussion: The results of variance analysis confirmed the diversity of all studied traits among all genotypes studied. The simple correlation coefficients among the traits showed that the weight of the boll and the number of bolls per plant had a positive and significant correlation with plant yield with correlation coefficients of 0.85 and 0.61 respectively at 1% probability level. Based on the results of stepwise regression analysis, the weight of the boll weight and the number of bolls per plant were 75.60% of the variation in plant yield. The results of causal analysis indicated that the most direct and positive effects were related to the weight of the boll weight (1.104). The number of boll/bush had the most indirect effect (0.916) on plant yield through boll weights. Manuscript profile
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        37 - Study of effective factors on reducing wheat grain yield in Mahdasht region of Karaj
        Seyyed Ali Mosavi Fayaz Aghayari MEHDI REZAEE
        One of the main problems of crop production in our country is the difference between the actual grain yield of farmers and the achievable grain yield or the yield gap. In order to investigate the management factors affecting the reduction of wheat yield in Mahdasht of K More
        One of the main problems of crop production in our country is the difference between the actual grain yield of farmers and the achievable grain yield or the yield gap. In order to investigate the management factors affecting the reduction of wheat yield in Mahdasht of Karaj, a field experiment was conducted in the crop year 2017-18 in the farms of Mahdasht which was previously selected by the researcher. In this study, using stepwise regression, the contribution of all management factors that may play a role in reducing yield has been investigated. The results of correlation between different factors showed a positive and significant correlation between grain yield with the number of irrigations, nitrogen application in the second stage, total nitrogen consumption during the growing period and micronutrient consumption at a probability level of 1%, and there was a positive and significant correlation with the area under cultivation at the 5% probability level. According to the recorded wheat grain yield values, the average actual wheat grain yield was 4775 kg.ha-1 and factors affecting yield reduction in this area including the number of irrigations (42%), area under cultivation (9%), previously cultivated crop (6%) and total nitrogen consumption (5%) were determined. Other management factors had little effect on grain yield reduction. Potential grain yield in Mahdasht of Karaj according to the regression model can be raised to 7630 kg.ha-1, and the grain yield gap in this area is 2860 kg.ha-1. Manuscript profile
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        38 - Relationship between grain yield and yield components of barley genotypes by multivariate statistical methods
        Ali Ahmadi Raziyeh Pourghasemi Tahmaseb Hosseinpour
        To assess some traits of 20 barley genotypes, the experiment was done in a randomized complete block design with four replications in Agriculture and Natural Resources Research Station, of Khorramabad in 2011-2012 growing season. Grain yield and some other agronomic tra More
        To assess some traits of 20 barley genotypes, the experiment was done in a randomized complete block design with four replications in Agriculture and Natural Resources Research Station, of Khorramabad in 2011-2012 growing season. Grain yield and some other agronomic traits were measured. Differences between genotypes were compared in terms of plant height, biological yield, grain yield and hectoliter weight was significant. Genotypes of 1 and 15 had the highest grain yield. Simple correlation coefficients indicated that grain yield, biological yield, straw yield and spike weight had positive and significant correlation. Highest correlation was observed in grain yield and biological yield (r = 0.90**). The results of stepwise regression analysis showed biological yield, spike weight, flag leaf length, flag leaf area, spike length, awn length were the traits influencing on grain yield. Therefore, these attributes can be considered as the most important plant characteristics and they could be a suitable choice to improve the yield of barley genotypes breeding programs. Spike weight, biological yield had the highest direct effect on grain yield. Also, Genotypes of 1 and 15 had the highest yield. The traits such as weight, spike, flag leaf length, flag leaf area, awn length and head length which had high correlation with grain yield were effective on yield increment. Manuscript profile
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        39 - Recognition the effective traits on grain yield of bread wheat genotypes under heat stress and non-stress conditions
        Hossein Ali Fallahi atefeh kaviani charati Abbas ali Andarkhor
        10.22034/aej.2018.538401
        To determine the traits affecting grain yield, 10 bread wheat genotypes including Morvarid and Kohdasht cultivars and Lines of N-87-4, N-87-9, N-86-6, N-86-8, N-80-19, N-86-5, N-85-5 and Line 17 were planted in two separate experiments including environmental condition More
        To determine the traits affecting grain yield, 10 bread wheat genotypes including Morvarid and Kohdasht cultivars and Lines of N-87-4, N-87-9, N-86-6, N-86-8, N-80-19, N-86-5, N-85-5 and Line 17 were planted in two separate experiments including environmental conditions without heat stress in 15 December, and heat stress conditions of 10 February in Gonbad Kavous Agricultural Research Station during 2011-2012. Genotypes were compared in a randomized complete block design with three replications andwith combined analysis. Interaction of heat stress and genotypes were significant for grain yield, spike length, number of fertile spike. Genotypes and heat stress effect in all recorded traits were significant. In both conditions, grain yield had a positive and significant correlation with number of fertile spikes. Stepwise regression showed that the number of fertile spikes in normal conditions 99.8% and in heat stress 97.1% of grain yield changes were explained. The path analysis showed that the number of fertile spike had the most direct effect on grain yield in both conditions. The cluster analysis categorized genotypes into two group in normal conditions and three groups in heat stress conditions. Therefore, the number of fertile spikes can be used indirectly in the selection of genotypes with high yield in both heat and normal conditions. Manuscript profile
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        40 - Relationship of some agronomic traits affecting grain yield in bread wheat recombinant lines under salinity stress conditions
        Sajad Soori Amin Baghizadeh Ghasem Mohammadi-nejad
        10.22034/aej.2016.525848
        Soil salinity is one of the abiotic stresses and a major problem to have a high yield in wheat. To awareness of relationship between agronomic traits and grain yield in salinity and to determine the traits affecting yield and tolerance to salinity, the Correlations coef More
        Soil salinity is one of the abiotic stresses and a major problem to have a high yield in wheat. To awareness of relationship between agronomic traits and grain yield in salinity and to determine the traits affecting yield and tolerance to salinity, the Correlations coefficients of different traits and path analysis of grain yield in salinity conditions were investigated. 322 recombinant inbred lines of wheat derived from crosses Roshan and Falat with parents were evaluated in simple lattice design 18 x 18 with two replications. The Experiment was conducted in the 2013-14 crop season at a farm in Ekhteiar Abad in Kerman with EC = 12 ds/m. The simple correlation coefficient among grain yield and the most of evaluated traits had significant positive correlation. The total weight of spikes per plant had the highest positive correlation and significantly with yield. Stepwise multiple regression analysis method showed that the total weight of spikes per plant, harvest index, biological yield and Number of fertile tillers were the most effect on grain yield. Path analysis based on variables in the final stepwise regression analysis showed that biological yield and harvest index had high direct effect on grain yield. Line number 56 having a higher yield than the parents and the other lines was selected as the best genotype in studied conditions. Manuscript profile
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        41 - Phenotypic diversity in families derived from cross between Badia and Komino barley cultivars
        Atefeh Kaviani Charati Hossein Sabouri HosseinAli Fallahi Eisa Jorjani
        10.22034/aej.2017.532506
        To study phenotypic diversity and relationship among agronomical traits of 100  barley  F3 generation families derived from cross between Badia × Komino barely cultivars, an experiment was conducted based on randomized complete block design with three re More
        To study phenotypic diversity and relationship among agronomical traits of 100  barley  F3 generation families derived from cross between Badia × Komino barely cultivars, an experiment was conducted based on randomized complete block design with three replications at research field of Gonbad Kavous University during 2014-2015. Barley families had significantly high diversity in terms of awn length, spikelet no/spike. Grain yield was positive significantly correlated with total spike weight, seedlings number, plant height, awn length and biological yield and the highest correlation was observed between grain yield and total spike weight. In stepwise regression analysis, traits of seedlings number, days to heading, grain diameter, grains per spike, awn length had high contributed to grain yield. In path analysis the trait that had the most direct effect on yield was seedlings number. Barely families were classified into three groups regarding cluster analysis using Ward method and the third group was chosen as desirable one. On the whole, The most important factors influencing on yield increment of barley families was seedlings number and days to heading and these traits could be suitable choices to be used in barley breeding improvement programs. Manuscript profile
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        42 - Genetic variation and inter-relationship between morphological characteristics and grain yield in advanced bread wheat (Triticum aestivum L.) cultivars using multivariate analysis
        Mina Sarabi alireza tarinejad varahram rashidi rahim alimohammadi
        Genetic diversity of 30 varieties of advanced bread wheat (Triticum aestivum L.) was studied. A field experiment was conducted using a randomized complete block design with four replications at the Research Farm of Islamic Azad University, Miyaneh Branch in 2009. All ag More
        Genetic diversity of 30 varieties of advanced bread wheat (Triticum aestivum L.) was studied. A field experiment was conducted using a randomized complete block design with four replications at the Research Farm of Islamic Azad University, Miyaneh Branch in 2009. All agronomic practices were carried out by current procedure. Nineteen traits included days to germination, stem elongation, heading, physiologic maturity, ripening, awn length, leaf number main stem, flag leaf area, penultimate flag leaf area, plant height, peduncle length, number of spike/m2, grain numbers/spike, 1000 grains weight, biologic yield, harvest index, grain filling period, straw yield and grain yield were measured. Data were analyzed using multivariate techniques like principle components, stepwise regression and cluster approaches. Principal components analysis showed that first and second components could explain a 75.51% of total variations. Based on the characteristics in the first and second components, first components were considered for yield and the second one for phonology traits. Stepwise regression analysis for grain yield as a dependant variable and other characters as independents revealed that grain number/ spike, spike/ m2, plant height and main spike length could explain 98.7% of the variations. Finally, examined variety were grouped in three clusters and the third cluster contained 23.3% of total variations which presented higher grain yield than the first and second groups. According to the results obtained in this study, N-76-16 line could be introduced as a high-performance genotype and would have advantages in the breeding programs. Manuscript profile
      • Open Access Article

        43 - Effect of partitioning and application of urea on safflower yield and its components
        Bahram Mirshekari Reza Siyami
        10.22034/aej.2016.525284
        To study the effect of urea application in safflower (Carthamus tinctorius) and determination of effective traits on its yield, a factorial experiment based on randomized complete block design in three replications was conducted in Tabriz, Iran, during 2012. Studied fac More
        To study the effect of urea application in safflower (Carthamus tinctorius) and determination of effective traits on its yield, a factorial experiment based on randomized complete block design in three replications was conducted in Tabriz, Iran, during 2012. Studied factors were urea rate levels as 100, 150 and 200 kg/ha and urea application times 100% in sowing time, 50% sowing time + 50% stem elongation, 25% sowing time + 50% stem elongation + 25% early flowering). Application of 200 kg/haurea had the highest seed number per anthodium. Number of secondary branches in 100 and 150 kg/ha urea application was more than 200 kg/ha. Safflower fertilizing with 150 kg/ha urea as 25% sowing time + 50% stem elongation + 25% early flowering lead to seed production with higher thousand seed weight of 31.8 g. Seed yield in fertilized plats with 150 kg/ha urea at 50% sowing time + 50% stem elongation was greater than other two urea doses. When plants fertilized with 150 kg/ha as 25% sowing time + 50% stem elongation + 25% early flowering or 50% sowing time + 50% stem elongation, oil yield was higher than 100% urea application in sowing time. The results of regression analysis revealed that thousand seed weight and number of secondary branches had higher positive effect on safflower yield. It is recommended to application of 75 kg/ha of urea in two or three parts of growth period for obtaining higher oil yield in safflower. Manuscript profile
      • Open Access Article

        44 - Determining the effective traits on bread wheat genotypes grain yield under drought stress and non-stress conditions
        Babak Hooshmandi
        To determine effective factors on grain yield under drought stress and non stress conditions at the end of the season, 15 bread wheat genotypes were examined as two separated experiments in Research Center of Faculty of Agriculture in Islamic Azad University, Tabriz Bra More
        To determine effective factors on grain yield under drought stress and non stress conditions at the end of the season, 15 bread wheat genotypes were examined as two separated experiments in Research Center of Faculty of Agriculture in Islamic Azad University, Tabriz Branch during 2012-2013. The cultivars were compared based on completely random block design with three replications. All studied traits were significant and there was frequent diversity among studied genotypes in the studied traits in both experimental conditions. The grain yield under non stress and stress conditions were 2.8 and 2.23 ha, respectively and drought stress had the most effect. The correlation coefficients among grain yield, biologic yield and harvest index were positive and significant in both experimental conditions and also grain yield under without stress showed a positive and significant correlation with number of spikelets per spike under stress conditions with spike length. According to stepwise regression under without stress conditions, number of spikelets per spike determined 40% of the grain yield changes. Also, in non stress conditions number of spikelets per spike and in stress condition spike length, plant height and pollination were most effective on grain yield and justified variation in grain yield and also genotype 14 showed higher yield relative to other genotypes in both experimental conditions. Manuscript profile

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