فهرست مطالب

Agricultural Science and Technology - Volume:20 Issue: 7, 2018
  • Volume:20 Issue: 7, 2018
  • Supplementury Issue 2018
  • تاریخ انتشار: 1397/09/27
  • تعداد عناوین: 19
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  • R. Moghaddasi *, S. Parva Pages 1333-1340
    Lack of adequate credit is among the major obstacles that Iranian agriculture, like many other developing countries, is facing. This study aimed at exploring the effect of formal credit on agricultural growth in Iran, using a unique provincial panel data set during 2000-2013. Different panel data econometrics techniques were applied. The main results indicated, on average, positive association between the sector growth and formal credit provided by the Agricultural Bank. The same relation was found for labor force. Meanwhile, public investment showed an indirect impact on the sector growth, though the size of effect differed among provinces. Redistribution of credits based on agricultural potentials of provinces is recommended as a key factor for increasing growth-related impact of credit.
    Keywords: Agricultural Bank, Econometric model, Labor force, Panel data, Public investment
  • J. Cikic *, T. Jovanovic , Mar. Nedeljkovic Pages 1341-1352
    Gender gaps limit rural women’s entrepreneurial potentials, preventing them to benefit from development activities. In this study, we assumed that there were gendered differences in rural tourism business. To examine this issue, we studied owners and employees in 57 rural tourism enterprises during the 2014 in seven districts of Vojvodina. The questionnaire with open and closed questions was used to examine main characteristics of managers and employees in rural tourism but also their perception of potentials and obstacles in rural tourism development. Results have shown gender differences in rural tourism regarding staff characteristics, motivation, business problems and knowledge, and innovation. Also, results have indicated the necessity of complementary use of qualitative and quantitative methodology in researching gender-tourism relations.
    Keywords: Lifestyle entrepreneurship, Micro-entrepreneurship, Rural development, Rural women
  • S. Mohammadi, Mehr , M. Bijani *, E. Abbasi Pages 1353-1367
    The natural environmental beauty preservation has become one of the most important human concerns in the present century, so that visual pollution is considered as a major obstacle to achievement of peace of mind and optimal perfection. In this respect, rural people have a major role in preserving the beauty of the natural environment. The purpose of this study was to analyze factors affecting the aesthetic behavior of Iranian villagers towards the natural environment. This study was descriptive-correlational and causal-relational and was conducted through a survey technique. Statistical population of this study consisted of all villagers in Kermanshah Province (as an indicator example of Iran) (N= 517,786). By using Krejcie and Morgan’s sample size table and stratified random sampling method, 385 people were selected as a sample. Research instrument included a questionnaire with approved validity by a panel of experts in the field of agricultural extension and education; and reliability of its items was obtained by a pilot study and calculation of Cronbach's alpha (0.64≥ α ≥0.82). Based on the findings, the causal model of factors affecting the aesthetic behavior of villagers was drawn. Results of this causal analysis indicated that ‘place attachment’ (β= 0.275) and ‘environmental aesthetic attitudes’ (β= 0.260) had highest effects on villagers' environmental aesthetic behavior, respectively. Therefore, by focusing on these two variables, the villagers' aesthetic behavior can be enhanced.
    Keywords: Aesthetic, Causal analysis, Place attachment, Rural people
  • O. Jamshidi , A. Asadi *, Kh. Kalantari , H. Azadi Pages 1369-1382
    The purpose of this study was to evaluate perception towards climate change, level of knowledge and climate change related behavior of agricultural professionals in Hamadan Province, Iran. The statistical population of the study consisted of 360 agricultural professionals and, by using Cochran formula, sample size was determined as 121 people, who were chosen via a simple random sampling method. Data was gathered using a structured questionnaire whose face validity was confirmed through a panel of experts and its reliability was estimated using Cronbach Alpha coefficient (above 0.70). The results revealed that mean age of sample study was almost 45 years and more than half of them had MSc. and PhD. degrees. Also, results showed that 91.7% of the respondents had strong perception, and about half of the respondents had high knowledge of climate change. While a great majority (78.5%) of the respondents was willing to join the practical efforts to mitigate effects of climate change, about one-fourth indicated they were willing to sacrifice some individual benefit to solve existing problems. The results indicated a significant (P< 1%) difference between 3 major job groups, i.e. managers, faculty members, and experts, regarding climate change related behavior. Also, correlation analysis confirmed that education level, knowledge of climate change, and perception of climate change had a significant relation with climate change related behavior.
    Keywords: Adaptation, Effects of climate change, Environmental issues, Individual characteristics, Public perception
  • G. Halik *, A. Lozicki , J. Wilczak , E. Arkuszewska , M. Makarski Pages 1383-1394
    The study was performed with 40 Simmental cows divided into four groups (treatments). The group I received diet with grass silage, maize silage, and concentrate. Group II was fed similar as group I plus 400 mg d-1 cow-1 of β-carotene. In group III, 40% maize silage DM was replaced with pumpkin silage to ensure a 400 mg higher β-carotene intake compared to the group I. In group IV, 60% of maize silage DM was replaced with pumpkin silage without balancing β-carotene. Milk samples were collected at 4 and 8 weeks of experiment. The milk was analyzed for the basic composition, carotenoids, Total Antioxidant Status (TAS), and composition of fatty acids. In both measurements, the highest content of α-carotene, β-carotene, lutein, violaxanthin were in the milk of group IV, and the lowest in group I. In the milk groups III and IV, higher content of PUFA, including n-3 PUFA, was found in successive samplings. In all samplings, milk TAS in group I was significantly lower compared to groups III and IV.
    Keywords: ?-carotene, Carotenoids, Fatty acid, PUFA, Simmental cows
  • M. Majzoobi *, A. Alishahi , A. Farahnaky Pages 1395-1406
    Starch and Soy Protein Isolate (SPI) have numerous applications in food products mostly as gelling and texturizing agents. The main purpose of this research was to investigate the pasting and gelling properties of the mixtures of starch and various levels of SPI (0, 5, 10, 15, 20 and 25%). To determine the effects of starch sources on the results, wheat and corn starches were tested in this study. It was found that with increasing the quantity of SPI, the viscosities obtained from Rapid Visco Analyser (RVA) including final, holding, and setback decreased while pasting temperature remained unchanged. Increasing the SPI concentrations enhanced the peak viscosity of the wheat starch-SPI samples, while it had opposite effects on corn starch-SPI samples. The colour of both starch-SPI gels became darker and more yellowish with increasing the SPI concentration. Although gel hardness increased during storage for 1 and 3 days at 4˚C, the addition of SPI reduced the hardness of the gels. The residual modulus of the Maxwell model from stress relaxation data showed that gels became softer and less elastic with increasing the SPI concentration. The corn starch-SPI gels exhibited darker color, higher firmness, cohesiveness, springiness, gumminess and chewiness compared to the wheat starch-SPI gels. The results may be useful to obtain the desired quality in food products containing starch and SPI.
    Keywords: Carbohydrate, Cereal starch, Starch-protein gel, Starch-protein mixture
  • H. Fallah , S. Khorasani , A. Mohammadi , M. H. Azizi *, M. Barzegar , Z. Hamidi Esfahani Pages 1407-1416
    One way to protect food and nutrients is to use gamma irradiation. Gamma rays are capable of influencing fatty acids, thus, this research was carried out to test the impact of using gamma rays on pistachio stored for six months and to determine the optimal effective dose of gamma with no negative impact on the amount of fatty acids in different types of pistachios. Three doses including 3, 5, and 9 kGy of gamma rays were used to protect and store different pistachios in Kerman. After being exposed to gamma rays, the pistachios were stored for six months in a storehouse at 5°C and (9-43%) RH. Every three months, the samples were analyzed. The greatest amount of oleic acid was found in Ahmad Aghaei pistachio type (62.08%) followed by Ohadi (61.03%), Kaleh Qouchi (59.83%), and Akbari (55.80%) types (P< 0.05). Over time, oleic acid and unsaturated fatty acids decreased in all of the control and test samples. After three months of storing, in Ahmad Aghaei pistachios irradiated with a 3 kGy dose of gamma, the amount of oleic acid fatty acid was 45.15%. With 5 kGy dose, after three months, oleic acid fatty acid was 66.65%, and with 9 kGy dose after three months, it was 59.90%. Therefore, it can be concluded that the use of irradiation doses of 5 and 9 kGy affects the increase of unsaturated and derived fatty acids, thus, the dose of 5 kGy irradiation is most appropriate.
    Keywords: Ahmad Aghaei pistachio, Fatty Acid Profile, Gamma Irradiation, Oleic acid, Storage
  • P. Attarod *, S. Miri , A. Shirvany , V. Bayramnejad Pages 1417-1429
    We aimed to find the meteorological parameters that affect variations in Leaf Area Index (LAI) of Persian oak (Quercus brantii var. persica) trees in the Zagros region of western Iran. Canopy developmental stage for five individual trees using a fish eye camera was monitored from August 2015 to August 2016. Meteorological parameters of Temperature (T), Precipitation (P), and Wind Speed (WS) were obtained from the nearest meteorological station during 1986-2016. FAO Penman-Monteith (PM) combination equation was employed to calculate daily reference Evapotranspiration (ET0). The nonparametric Mann–Kendall (MK) test was used to detect significant changes in yearly meteorological parameters and ET0. Over the study period, LAI varied from zero during the LeafLess Period (LLP), when the Woody Area Index (WAI) was 0.88, to 1.65 in Full Leaf Period (FLP). LAI showed relatively strong and significant positive linear correlations with T (R2= 0.71), Vapor Pressure Deficit (VPD) (R2= 0.58), and ET0 (R2= 0.33), such that higher LAI values were measured in warmer and drier days with higher ET0. No statistically significant trend was detected by MK test during 1986-2016 for yearly T and VPD (MK statistic, ZMK= 0.044 for T, and ZMK= 0.207 for VPD). Significant relationship between leaf area index of oak trees and temperature in the Zagros region can partially confirm the connection between declining oak trees and rising temperature.
    Keywords: Evapotranspiration, Meteorological parameters, Oak trees, Zagros region
  • R. Faez , Y. Fathipour*, A. Ahadiyat , M. Shojaei Pages 1431-1442
    To examine the effect of Citrus Red Mite (CRM) damage on quantitative and qualitative characteristics of Thomson navel orange Citrus sinensis (L.) Osbeck, paired-treatment experiment, multiple treatment experiment, and regression/correlation methods were used. There were significant differences among the treatments in paired-treatment and multiple treatment experiments in terms of the average population per leaf of CRM of different life ages and concentration of chlorophyll in the leaves. Also, there were significant differences among the treatments in multiple treatment experiment in terms of the Total Soluble Solids (TSSs) of the fruit extract. In control treatment of the paired-treatment experiment, the highest concentration of chlorophyll (79.13±1.06) was observed when the population density of CRM was 0.48±0.09 per leaf. With increasing the mean number of CRM to 10.59±1.09 per leaf, chlorophyll content was decreased to 62±1.15. Furthermore, the results showed that the storage life of the fruits in treatments with mean number of 6.33±1.8 mites per leaf was significantly reduced. The results of regression and correlation analysis on chlorophyll showed significant and negative relationship between these parameters and CRM population density. The results indicated that increasing the population density of CRM to 10.59±1.09 per leaf at the beginning of the season caused fruit drop and dry twigs. In addition, by increasing population density of CRM to 5.72±0.43 per leaf, the storage capability of the fruits was significantly reduced.
    Keywords: Citrus red mite, Crop loss assessment, Quality loss, Yield loss
  • B. Barczak *, H. Klikocka Pages 1443-1453
    In view of the increasing sulphur deficiency in Poland’s soils, in 2007-2010, a field experiment was performed with white mustard (Sinapis alba L.) in Haplic Luvisol with low sulphur content (mean – 9.4 mg kg-1). The aim of the research was to evaluate the effect of varied sulphur application methods (foliar and pre-sowing soil application), forms (elemental and ionic), and rates (0, 20, 40, 60 kg S ha-1) on the content of protein in mustard seeds, as well as on its amino acid and fraction composition. The research showed that of all the studied factors, the sulphur application rate affected the protein content the most. As compared with the control, sulphur application increased the overall sums of essential and dispensable amino acids in the mustard seeds as well as their quantitative ratio. The biological protein value indices (Chemical Score and Essential Amino Acid Index) point to a clearly positive effect of sulphur on the amino acid composition of the protein, including sulphur-containing methionine, an amino acid limiting protein biosynthesis. The sulphur rate significantly affected the content of all the protein fractions assayed, except for glutelins.
    Keywords: Amino acid composition indices, Exogenous, endogenous amino acids, Protein quality
  • R. Moradi Talebbeigi , S. A. Kazemeini *, H. Ghadiri Pages 1455-1466
    A 2-year field experiment was conducted to evaluate the effect of N sources [Ammonium Nitrate (AN), Ammonium Sulfate (AS), Sulfur Coated Urea (SCU), and Urea (U)] and split application ((1/4,3/4,0), (1/3,1/3,1/3), (1/2,1/2,0), and (1/3,2/3,0)) on weed growth, safflower (Carthamus tinctorius L.) yield, and N Use Efficiency (NUE), using a split split-plot design with three replications, at the Experimental Research Station of Shiraz University, in 2015 and 2016. In weedy plots, applying AN-fertilizer in a split pattern of 1/2,1/2,0 (applying half of the N at sowing time and the rest at stem elongation) increased weed infestation. This treatment enhanced total weed N Uptake Efficiency (NUpE) up to 5% compared to U-fertilizer and similar split pattern. In weed free plots, the highest seed and oil yields (3303.52 and 753.09 kg ha-1, respectively) were achieved by AN- and U-fertilizers in a split pattern of 1/2,1/2,0. Applying AN fertilizer and split patterns of 1/3,2/3,0 (one third of N at sowing and two thirds at stem elongation) and 1/4,3/4,0 (one quarter of N at sowing and three quarters at stem elongation) maximized safflower NUpE (0.78 kg kg-1). Applying U fertilizer and split pattern of 1/2,1/2,0 increased safflower ability to compete vs. weeds up to 20% compared to AN-fertilizer. Overall, in order to improve safflower yield and NUE and control weed, applying U-fertilizer and split application of 1/3,2/3,0 or 1/4,3/4,0 can be suggested as a component of integrated weed management programs.
    Keywords: Ability to compete index, Fertilizer management, Nitrogen efficiency, Redroot pigweed
  • M. Safar, Noori , Q. Dong , H. Saneoka * Pages 1467-1477
    The present research was conducted to study the effect of NPK fertilization on wheat grain yield, minerals concentration, grain quality, gluten, pentosan, and phytate phosphorous (phy-P) content, and the influence of maternal plant NPK fertilization on the seed physiological attributes during the germination period. NPK treatments comprised a control, where no fertilizer was applied (T0), and two levels of NPK fertilizer: T1 (110 kg N+60 kg P2O5+55 kg K2O ha-1), and T2 (200 kg N+120 kg P2O5+100 kg K2O ha-1). Winter wheat was grown in a greenhouse during the growing season of 2015-16, following randomized complete block design with 4 replicates. The results indicated that a high level of NPK (T2) fertilization increased the grain yield, crude protein, water-soluble pentosan, and dry gluten, up to 151.6, 65.3, 40.5, and 408.9% compared to the control, respectively. It also enhanced the grain mineral concentration, but did not affect the grain starch significantly. Grain phy-P was increased with a high NPK fertilization and, interestingly, the level of phytase enzyme was also increased up to 46% in T2 compared to the control. Moreover, maternal plant NPK fertilization enhanced seed germination percentage, seedling fresh weight, phytase activity, inorganic phosphorus, and phy-P metabolism during the germination period. From the results of this study, it was concluded that grain nutritional quality was improved with increasing NPK rates, but antinutritional compound phy-P was also increased, while it may enhance seed viability, germination, and seedling vigor.
    Keywords: Germination, NPK, pentosan, phytate, wheat
  • F. Behboudi , Z. Tahmasebi Sarvestani , M. Z. Kassaee* , S. A. M. Modares Sanavi , A. Sorooshzadeh Pages 1479-1492
    Silicon (Si) and its derivatives have beneficial effects on a wide variety of plant species, especially under both biotic and abiotic stresses. Yet, their effects on wheat (Triticum aestivum L.) plants under drought stress are not well known. Therefore, in order to evaluate the effects of SiO2 NanoParticles (NPs) under drought stress, wheat seeds were separately sown in pots. Then, the SiO2 NPs were added to them through soil and foliar application at three stages of plant growth. Results indicated that drought stress significantly decreased majority of the studied traits compared to the normal irrigation. Soil application of NPs, under drought stress, significantly increased leaf greenness (SPAD) and Relative Water Content (RWC) by 12.54 and 84.04%, respectively, compared to the control (NPs= 0 ppm). Moreover, under drought stress, wheat yield also increased by 25.35 and 17.81%, respectively, by foliar and soil application of NPs. Under the same irrigation regimes, soil application of NPs significantly increased plant height and biomass compared to the foliar application of NPs. Finally, our results highlight that usage of the SiO2 NPs, especially at rates of 30 and 60 ppm, can mitigate adverse effects of drought stress in wheat plants.
    Keywords: Biomass, Foliar application, Grain protein, Leaf area, Relative water content, SPAD
  • A. R. Fakoor Sharghi , H. Makarian *, A. Derakhshan Shadmehri , A. Rohani , H. Abbasdokht Pages 1493-1504
    Estimating the spatial distribution of weeds for site-specific control is essential. Therefore, this research was conducted to predict and interpolate the spatial distribution of Amaranthus retroflexus L. populations using a Radial Basis Function Neural Network (RBF-NN) in two potato fields. Weed population data were collected from sampling 200 and 36 points, respectively, in two commercial potato fields in Jolge Rokh, of Torbat Heidarieh in Khorasan Razavi and Mojen of Shahroud in Semnan Provinces, Iran, in 2012. Some statistical tests, such as comparisons of the means, variance and statistical distribution, as well as linear regression, were used for the observed point sample data and the estimated weed seedling density surfaces to evaluate the neural network capability for predicting the spatial distribution of the weed. The results showed that the trained RBF-NN had high capability in the spatial prediction in points that were not sampled with 100% output, 0.999 coefficients, and an average error of less than 0.04 and 0.07 in the Mojen and Jolge Rokh Regions, respectively. Test results also showed that there was no significant difference between the statistical characteristics of actual data and the values predicted by the RBF-NN. According to the experimental results, the RBF-NN can be used as an alternative method to estimate the spatial changes function of annual weeds with random dispersion, such as Redroot Pigweed.
    Keywords: Density estimation, Patchy distribution, Precision management, Radial Basis Function
  • S. Mafakheri *, B. Asghari Pages 1505-1516
    Modern agriculture is searching for new biotechnologies that would allow for a reduction in the use of chemical inputs without negatively affecting crop yield or farmers' income. Seaweed extract and humic acid are used as nutrient supplements, biostimulants, or biofertilizers in agriculture and horticulture to increase plant growth and yield. To investigate the effects of SeaWeed Extract (SWE), humic acid, and chemical fertilizers on the growth, physiological and biochemical characteristics of Trigonella foenum-graecum L., a greenhouse experiment was conducted in 2016. Results showed that foliar applications of seaweed extract enhanced growth parameters. Among the different treatments, the plants that received SWE showed maximum shoot lengths, fresh and dry weights, number of pods per plant, chlorophyll “a”, chlorophyll “b”, total chlorophyll, and carotenoids. Also, application of SWE increased the amount of total phenolic and flavonoid contents in fenugreek. All fertilizer treatments increased significantly 2,2-DiPhenyl-1-PicrylHhydrazyl (DPPH) radical scavenging activity of the plants in comparison to the control. Plants treated with SWE showed stronger activity against α-glucosidase with IC50 value of 171.37 μg mL-1 in comparison with acarbose (IC50= 19.7 μg mL-1) as the reference α-glucosidase inhibitor. The data generated by this study revealed that SWE could be used as foliar spray to maximize the quality and quantity of fenugreek.
    Keywords: Antioxidant activity, Biofertilizers, Fenugreek, Phenolic compound
  • B. Bakshi , R. Kumar , G. Kour , V. K. Vali , D. Bhat , T. K. Hazarika * Pages 1517-1524
    An investigation was conducted during 2012 and 2013 to study the fruit developmental stages pertaining to quality characteristics for fixation of maturity standards in three aonla cultivars viz., NA-6, NA-7 and NA-10 under rainfed conditions of Jammu subtropics, India. The results of the present investigation revealed that various physical and quality parameters were very useful in fixing maturity standards in aonla. Fruits were harvested at different maturity periods at weekly intervals and were evaluated for different physicochemical characteristics. It was observed that initially fruit growth was faster and slowed down between first week of November to last week of November and increased thereafter and followed a double sigmoid growth pattern in all the three aonla cultivars. Fruit weight of aonla ranged from 0.8 to 36.5 g in NA6, 0.93 to 36.55 g in NA7 and 0.54 to 32.55 g in NA10. Specific gravity did not show any specific trend at different maturity stages in all the cultivars. TSS, sugar, and TSS/acid ratio increased as the fruits reached toward maturity. Titratable acidity and chlorophyll content showed decreasing trend. In all cultivars, ascorbic acid increased during development and remained constant till fruits attained physiological maturity. The ideal time for harvesting of aonla was found to be the last week of December and first week of January depending on cultivar.
    Keywords: Biochemical parameters, Harvesting time, Physical parameters, TSS-acid ratio
  • M. M. D. Coan *, V. S. Marchioro , F. de A. Franco , R. J. B. Pinto , C. A. Scapim , J. N. C. Baldissera Pages 1525-1540
    The objective of this study was to evaluate the adaptability and stability of wheat genotypes simultaneously in unbalanced Multi-Environment Trials (MET) in four different regions of Brazil, using the method of harmonic means of the relative performance of genetic values. Mixed model was applied to the analysis of Genotype- Environment Interaction (GEI) in wheat. Grain yield data were obtained from a network of MET carried out at seven locations from 2008 to 2010. A joint of experiments in complete randomized blocks design with some common treatments was used in all 21 experiments. Adaptability and stability parameters were obtained by several different methodologies, based on prediction, Harmonic Mean, and of the Relative Performance of Genotypic Values (HMRPGV). These methodologies ranked in a very similar way the studied genotypes and indicated the genotypes CD0950, CD0857, CD0667, CD0915, CD0914, CD0669, CD0859, and CD0851 as the superior ones for grain yield, adaptability, and stability in all environments. Dourados-MS (2010) was the worst environment with lowest mean (1,560.26 kg ha-1) and São Gotardo–MG (2008) was the best environment with highest mean (5,687.08 kg ha-1). The genotype more stable by HMRPGV across 21 environments tested was CD085; in the best environment, it was ranked the sixth (6,319.30 kg ha-1), but changed your values in the worst environment and was ranked the fifth (2,051.53 kg ha-1). The HMRPGV proved to be a practical and useful statistical tool in the determination of the Value for Cultivation and Use (VCU), particularly in the selection of genotypes’ reliability when genotypes are selected for the environments evaluated. This method has the advantage of providing results that are directly interpreted as breeding values ​​for yield, stability, and adaptability.
    Keywords: Genetic values, REML-BLUP, Triticum aestivum L. Interblock
  • M. Ghashghaie , H. Nozari * Pages 1541-1553
    Lake Urmia is one of the water bodies that face severe drought conditions nowadays. Therefore, the present study aimed to study monthly time series of the lake water level. Modeling the series was accomplished in two ways. First, all data were used to analyze the water level time series of the lake. Although the results of generating were quite well, the results of validity test were not satisfying. Second, only water level data after the year 1995 were used, which showed a continuously decreasing trend. These data start from the year when dam constructions and operations in Urmia Watershed were increased one by one. The values of R2 and RMSE were 0.99, 0.001 m, respectively, for generating the data at this stage. These values were 0.93 and 0.03 m for the validity test of the model (from 2005 to 2009). The results of our study show that the lake water level behavior changed after 1995 due to constructing many dams in Urmia Lake Watershed.
    Keywords: Lake Urmia, Water level, Trend, ARIMA
  • J. Pirvali Beiranvand , A. A. Pourbabaee *, S. P. Shirmardi , H. A. Alikhani , A. R. Abbassi , B. Motesharezadeh Pages 1555-1564
    The objectives of the present study was to evaluate biological nitrogen fixation, P and K uptake ability of 31 soybean mutant lines (induced by Gamma irradiation) and their parent cultivar at greenhouse level. Initially, 10 Rhizobial isolates and strains were tested for infectiveness and symbiotic effectiveness using Leonard jars, and the strain Bradyrhizobium japonicum strain RS 152 was selected as the most efficient strain. The experiment was conducted under proper greenhouse condition with a randomized complete block design on a soil with no indigenous rhizobia and low nitrogen and phosphorus content. Thirty-one soybean mutant lines and two inoculated and un-inoculated wild cultivar blanks were replicated three times. Each pot contained 3.5 kg air-dried homogenized soil, and at the time of planting each seedling was inoculated with l mL of inoculum RS 152 containing approximately 9 × 108 cells per mL. During about 4 months of growth, the plants were irrigated to maintain the soil moisture approximately 0.8 field capacity. The plants were harvested at the plant developmental stage of pod filling (R6), and several parameters, such as dry matter of shoot, nodule and roots, number of nodules, and proportion and amount of Nitrogen derived from air (Ndfa% and N-fixed) were measured. According to the results, in most parameters, the mutant lines were significantly different with each other and also with the L17 parent soybean cultivar. The mutant line 5 showed the maximum value of %Ndfa (73.068) compared to the cultivar L17 (48.762), indicating significant increase of biological nitrogen fixation, by about fifty percent, through physical mutagenesis. In addition, the mutant lines 21 and 31 had higher phosphorus and potassium uptake than the others, however, significant differences were observed for phosphorus uptake capacity compared to the cultivar L17. Although more detailed studies are needed to evaluate effects of these mutations on nitrogen fixation, macro- and microelements absorption capacity, and also on yield and quality parameters, these findings show that gamma irradiation could be helpful to induce new nutritional properties in soybean and release new mutant cultivars.
    Keywords: Biological nitrogen fixation, Ndfa, Nutrient efficient genotypes, Physical mutagenesis