Showing 17 results for mohamadi
M. Shivazad, H. Janmohamadi,
Volume 6, Issue 1 (spring 2002)
Abstract
A Complete Randomized Block design was used to study the total protein efficiency (TPE) in Iranian Kilka and Peruvian Anchovy fish meals. Six isoenergetic (3200 kcal ME/kg) and isonitrogenous (18.5% CP) diets based on corn with six samples of fish meal (No. 1, 5, 6 steam processed, 2, 4 flame processed Kilka fish meal and No. 3 Peruvian Anchovy fish meal) were formulated and fed to Lohman male chicks from 7 to 42 days of age. Feed consumption and weight gain were measured weekly. Total protein efficiency and feed conversion (FC) were calculated and statistically analyzed.
The highest TPE values in fish meals obtained over the period of 7-28 days and significantly differed (P< 5%) among Kilka and Peruvian fish meals. With the exception of sample No. 5, the highest values of TPE obtained in the case of steam processed and the lowest obtained the case of flame processed Kilka fish meals. The TPE value of Peruvian fish meal was approximately equal to the average of the two types of processed Kilka fish meals. The orthogonal and nonorthogonal comparison of TPE and feed conversion (FC) in Kilka fish meals, regardless of the type of processing, with the same values in Peruvian Anchovy fish meal did not show any significant differences (P> 5%). With the exception of sample No. 5, the highest final weight of chicks obtained with steam processed Kilka fish meal. In general, TPE values in Kilka fish meals were variable when compared to Peruvian fish meal and TPE of steam processed Kilka fish meal was better.
M. Mohamadi Bazargani, B. E. S. Tabatabaei, A. Rezaei, C. Ghobadi,
Volume 8, Issue 2 (summer 2004)
Abstract
Optimizing regeneration of cotton plant in two variety (Sahel and Varamin) via shoot apex was done in order to Agrobacterium-mediated transformation. In this reaserch shoot apexes of two varieties were isolated from four or five day seedling and were placed on a special medium of shooting (modified MS without hormon).In order to select the best rooting media, The Statistical Analysis explants that produce shoot and leaves in a CRBD with 4 replicates and 4 rooting treatments: 1) modified MS without hormon, 2) ½ MS with 0.1 mg/lit IBA, 3) ½ MS with 0.1 mg/lit NAA, 4) ½ MS with 0.1 mg/lit IAA. The statistical analysis indicated that the best for both varieties, was medium with 0.1 mg/lit IBA and rooting percentage of Varamin is better than sahel in all of media.
M. Shahmohamadi, H. Dehghani, A. Yousefi,
Volume 9, Issue 1 (spring 2005)
Abstract
To determine yield stability and to evaluate genotype interaction with environment interaction, 18 genotype of barley (Hordeum vulgare L.) and a control group were evaluated in a randomized complete block design with 4 replications in 3 successive years (1997-2000) at 10 research stations. Simple and combined analysis of variance revealed significant genetic differences between yield genotypes for grain yield. The results of combined analysis of variance indicated that genotypic and genotype were significant through interaction with environment. Therefore, different stability parameters including, environmental variance (S2i), environmental coefficient of variation (C.Vi), mean of variance of interaction (θi), interaction variance (θi), equivalence ( W2i), stability variance (σ2i), linear regression coefficient (bi, βi), mean of squares of deviation from regression (S2 di) and years within location MS for a genotype, averaging over all locations (MSy/l) were determined. Based on all the stability parameters, genotype 18 was known as the most stable one and genotypes 17 and 11 ranked lower. Genotype 5 with the highest yield was known to be the most adaptable one at fertile environments and is recommended for these locations. In addition, genotype 9 with good yield and low yield variance (1.58) and regression coefficient of less than 1 is suggested for unfertile locations.
F Valimohamadi, M Tajbakhsh, A Saeed,
Volume 12, Issue 46 (fall 2009)
Abstract
In order to evaluate effect of planting date and plant density on grain yield, yield components and some quality and morphological traits of chickpea (Cicer arietinum L.), an experiment was conducted at the research center of agricultural and natural resources of west Azerbaijan in Urmia rain-fed research farm during 2005-2006 growing season in a split plot arrangement, based on a completely randomized block design with four replications. The cultivar of chickpea (Qazvin local mass) was planted in three sowing dates (mid November, mid March and mid April) in main plots, and four plant densities (intra row space: 7.5, 10, 15 and 20 cm) representing (45, 34, 23 and 17 plant/m2) in sub plots. Yield, number of pod per plant, seed protein content, plant height, number of secondary branches and 100 seed weight were evaluated. Results indicated that date of sowing had a significant effect on the yield, number of pod per plant and seed protein content but was not significant for plant height, secondary branches and 100 seed weight. Highest number of pod per plant was obtained in mid November sowing (37.69) and high protein content (22.63) in mid March. Different plant density effects were also not significant on yield, plant height, secondary branches and 100 seed weight but the effect of density on the number of pod per plant and seed protein content was significant. Highest number of pod per plant was obtained in the third density (31.5), and highest protein content in the first density (22.31). The results of study indicated that between mid March planting in the density (45 plant/m2) had highest yield (1042.08kg/ha) and protein content compared with the other planting dates.
R S.sharifi, A Javanshir, M Shakiba, K Ghasemi Golezani, A Mohamadi, Y Raei,
Volume 12, Issue 46 (fall 2009)
Abstract
In order to study yield component and determinate the contribution of stem reserves to corn yield under effect of different densities and interference periods of sorghum, a factorial experiment based on randomized complete block design with three replications was conducted in 2002 on the Research Farm of the Faculty of Agriculture Tabriz University. Experimental factors were sorghum interference at different periods (0,14,28,42 days after corn emergence and also during plant life corn) with three densities (4,8,12 plants m-2). Characteristics of study were yield, yield component and the contribution of stem reserves to corn grain yield. The results showed that with increasing sorghum density and interference, corn yield components (except the number of grain rows) were decreased, due to shading and competition between plants for using available resources. Maximum grain yield and grain number per ear was obtained at pure corn plantation. With increasing sorghum density and interference periods grain yield decreased, and maximum corn yield loss was 38%, which occurred at the highest sorghum density and interference. Dry matter remobilization and contribution of stem reserves were significantly influenced by sorghum densities and interferences in corn grain yield. The highest contribution of dry matter remobilization and stem reserves to corn yield was obtained at maximum density and complete interference of sorghum. The least contribution of reserves was shown in pure corn plantation. This might be related to shading and competition between plants for light and other resources.
S.h Sadeghi, S.h Pourghasemi, M Mohamadi, H Agharazi,
Volume 12, Issue 46 (fall 2009)
Abstract
The use of suitable empirical models for estimation of soil erosion and sediment yield is essential because of nonexistence or shortage of associated data in many watersheds. In the present study, the applicability of the USLE and its different versions Viz. MUSLE-S, AOF, MUSLT, MUSLE-E, USLE-M and AUSLE in estimation of storm-wise sediment yield from standard plots installed in dry farming, ploughed and rangeland treatments was evaluated. To conduct the study, the entire input data were collected from plots installed in three replicates in each treatment in Khosbijan Natural Resources Research Station in Arak Township. The models’ estimates were then compared with the observed sediment data for 12 storm events. Contrary to high correlation among different models’ estimates, the models used in estimation of measured sediment data were found inapplicable. However, significant relationship (r=94.4%) and non-significant relationship with correlation coefficients less than 50% were found between MUSLE-E, and MUSLE-S and MUSLE-E estimates and measured data in rangeland, dry farming and ploughed treatments, respectively.
G Golmohamadi, S Maroufi, K Mohamadi,
Volume 12, Issue 46 (1-2009)
Abstract
In this research, using geographic information system (GIS) and different geostatistical methods including the kriging and co-kriging (ordinary, simple and universal) as well as the radial basis functions, the spatial distributions of runoff coefficient were evaluated in Hamedan province. To this end, the annual runoff were calculated in 18 existing hydrometery stations and another 11 auxiliary points, using digital elevation model (DEM) and 11 years available data of the stations. The performance criteria for evaluating the methods were mean absolute error (MAE), mean bias error (MBE), root mean square error (RMSE), and general standard deviation (GSD) along with the cross validation examination. A high regression between the runoff coefficient and watershed average slope was selected as auxiliary variable. The results showed that the runoff coefficient of the region changes between 3.5 and 85%. The findings also indicated that the universal co-krigings with spherical semi-variogram model had better performance with the values of MBE (-0.0014), MAE (0.036), RMSE (0.054) and GSD (20.152). The universal and simple kriging with spherical model were equal in runoff estimation of the region and were ranked as the second methods to this propose.
L Izady, N Hamdami, A Mohamadi,
Volume 13, Issue 47 (4-2009)
Abstract
The microbial and enzyme activity in different points within cheese and quality of final product are determined by local concentrations of salt and moisture in aqueous phase. To predict the evolution of moisture content in different layers of the Iranian white cheese during brining, constant and variable moisture diffusion coefficients were determined using experimental moisture time–dependent concentration-distance profiles. These experimental profiles for Iranian white cheese were obtained in rectangular samples, ensuring semi-infinite unidirectional mass transfer within saturated solution of sodium chloride at different temperatures (6, 14, 19, 24 °C) and brining times (6, 24, 48 h). Results showed that moisture diffusivity increases with increasing temperature and moisture content in cheese aqueous phase. The variation of the moisture effective diffusivity as a function of temperature was represented by the Arrhenius’s relation. Finally, the relation of diffusivity with moisture content and temperature was developed. The predicted diffusivity values using the developed model showed a good agreement with the experimental values by using Boltzman variable method.
F Ghafori, M Eskandari, H Mohamadi,
Volume 13, Issue 47 (4-2009)
Abstract
Variance components and genetic parameters of body weight of Mehraban sheep were estimated by univariate and random regression models. This was done by using body weight records of 2746 Mehraban lambs related to flocks under supervision of the Agriculture Organization of the Hamadan province, collected between 1990 and 2005. In both methods, variance components estimates were obtained by restricted maximum likelihood (REML) using DFUNI and DXMRR programs, respectively, via DFREML 3.1 software package. Results showed that variance components obtained from RR models (except for residual variance) in some ages were higher than those obtained from univariate models. Direct heritability (h2) estimates from univariate and RR models were approximately equal to weaning age but, overall, RR estimates were higher than those obtained from univariate analyses. Maternal heritability estimates (m2) from RR models were higher than univariate models’ estimates, and showed a different pattern of variation with age. Correlations between predicted breeding values from univariate and RR models for birth weight and weaning weight were 0.72 and 0.70, respectively. Results showed that estimates of variance components and genetic parameters by RR models were affected by data structure and in case of the need for genetic parameters, especially those related to body weight late in lambs’ life, estimates of univariate analyses should be preferred.
M Talebi, M Bahar, Gh Saeedi, A Mohamadi,
Volume 13, Issue 47 (4-2009)
Abstract
To characterize the geographical distribution of medicago-nodulating rhizobia in western regions of Iran, 950 Sinorhizobium isolates were trapped from a combination of two local alfalfa populations (Hamedani, Nikshahri) together with a foreign cultivar ( Kodi) and soil samples from eight sites across Kurdestan, Kermanshah, Eastern Azarbayjan and Lorestan provinces. Also, a total of 45 isolates were obtained from nodules of naturally grown Melilotus officinalis (14 isolates) and Trigonella foenum-graecum (31 isolates) plants in Isfahan. On the basis of PCR partial amplification of the plasmid born nod box gene and chromosomal mucR gene of the isolates,16S ribosomal DNA PCR-restriction fragment length polymorphism analysis, and the nucleotide sequence, three isolates from alfalfa, seven isolates from M. officinalis and 13 isolates from T. foenum-graecum were proved to be Sinorhizobium medicae. The remaining isolates (943 from alfalfa, seven from M. officinalis and 18 from T. foenum-graecum) were identified as S. melilloti. Both species, S. meliloti and S. medicae, were recovered from nodules of all the hosts although S. meloti was clearly more dominant in nodulating different populations of alfalfa. Taken together, these results indicated that the abundance of S. meliloti is independent of the site of isolation and have a wide geographical distribution. In this study, the banding pattern resulting from PCR amplification of 16S rRNA gene, followed by digestion with Rsa I, clearly differentiated S. meliloti and S. medica strains, showing that PCR-RFLP is an appropriate method to discriminate medicago-nodulating rhizobian with relative rapidity.
Sh Mimohamadi, H Allahyari, M Nematolahi, A Sabouri, S Zarghami, Sh Khaghani,
Volume 13, Issue 47 (4-2009)
Abstract
The cabbage aphid Brevicoryne brassicae L. is an important pest, which attacks the rape seed and causes economic damage. In this study, effects of four different cultivars of rape seed (Zarfam, Licord, Hyola 401, and SLM046) on biological parameters and intrinsic rate of increase of B. brassicae were studied in laboratory conditions (25±1ºC, 70±10 RH and of 14:10 (L:D) photoperiod). Results showed that maximum nymphal and reproductive period, longevity of insects were found on Licord cultivar. The maximum fecundity of adult aphid was seen on Hyola 401. There was no significant difference between duration of developmental stages, and aphid fecundity on different cultivars. The intrinsic rate of increase was calculated by Wyatt & White method. Estimated intrinsic rate of natural increase of aphid was 0.316, 0.294, 0.311, and 0.289 on Zarfam, Licord, Hyola 401, and SLM046, respectively. Although the lowest intrinsic rate of increase was observed on Zarfam, statistical analysis of Wyatt & White output showed there was not any significance difference between rm on different cultivars.
] Esfandiarpor, M.h Salehi, N Tomanian, J Mohamadi,
Volume 13, Issue 49 (Water and Soil Science 2009)
Abstract
Geopedology is a systematic approach of geomorphic analysis for soil mapping that construct field operation mainly upon the work in sample area. The main goal of this research is to determine the effect of location of sample area and expert knowledge on credibility of generalization of the results obtained from geopedological approach for similar landforms in south-east of Borujen area. Upon preparation of primary interpretation map of the study area on air photos (1:20,000 scale), and considering different locations of Pi111 unit that encompasses the maximum surface of the study area, the sample area was planned in three different locations. Then, a second-order soil survey was conducted and final soil map was prepared. Also, two different experts were considered to determine the amount of credibility of generalization of the results obtained through geopedological approach for the mentioned unit. Results showed that changing the location of sample area has taxonomic levels (order, subgroup and/or family) and map unit type (complex and consociation) differences in Pi111 unit. In spite of similarity of the profiles selected by the two experts, soil taxonomies of these profiles were different in comparison with representative pedons (at family level). Therefore, the use of landform phases is recommended to increase the accuracy of geopedological results.
H. Kheirabad, A. H. Khoshgoftarmanesh, Z. Khanmohamadi,
Volume 16, Issue 62 (Winte - 2013 2013)
Abstract
Due to soil and plant zinc (Zn) deficiency and its effect on reducing yield and quality of agricultural products, application of Zn fertilizers has been intensified in recent years. To achieve optimum fertilizer management, knowledge of factors affecting Zn availability in soil and its uptake by plant is required. Therefore, this study was carried out to investigate the effect of certain soil physiochemical properties on Zn availability in soil and its uptake by corn. The experiment was laid out in a completely randomized design with factorial combination and three replicates in the research greenhouse of Isfahan University of Technology, in winter 2009. In this greenhouse experiment, 11 soil series were exposed to two Zn levels (0 and 15 mg Zn kg−1 in the form of zinc sulfate). The results indicated that Zn application significantly increased the dry matter weight and shoot and root Zn concentration of corn, although the magnitude of this increase varied depending on the soil type. There was no significant correlation between the DTPA-extractable Zn and the uptake of this nutrient element by corn. There was a negative significant correlation (P < 0.05) between the equivalent calcium carbonate content and available P with the DTPA-extractable Zn. A significant linear relationship (R2 = 0.31) was found between the buffer capacity of soil for Zn and clay content. According to the results obtained from the stepwise regression analysis, the DTPA-extractable Zn and buffer capacity of soil for Zn were not correlated with other measured soil properties.
N. Khanmohamadi, S. Besharat,
Volume 20, Issue 77 (Fall 2016)
Abstract
Accurate design of drip irrigation systems requires sufficient understanding of horizontally and vertically distribution of water flow in soil and modeling the wetting pattern dimensions created under the drip source. Field and laboratory activities are not suitable for this purpose considering their time and financial constraints and it is necessary to apply accurate software for determination of several equations in different situations. This research aimed to present simple models for calculation of wetting pattern dimensions in different discharges and structures in drip irrigation system. For this purpose, HYDRUS-2D model was implemented for four discharges in the same soil texture and different soil textures in the same discharge. The values obtained from running the software such as depth and maximum diameter of wetting pattern have been fitted with time values and corresponding equations were obtained. The results of statistical indices for all obtained equations (R>0.96, RMSE<2.12 and MAD<1.38) represent suitable accuracy of corresponding equations in determination of pattern dimensions under the drip source. The results also showed that Loamy Sand and Silt textures, respectively, have maximum and minimum depth and wetting pattern diameter.
O. Mohamadi, M. Heidarpour, S. Jamali,
Volume 23, Issue 3 (Fall 2019)
Abstract
Shortage of water resources and renewable per capita in last 30 years is put Iran on crisis threshold. Wastewater reuse is one of the battle solutions for water shortage and prevents wastewater depletion and environmental pollution. Thus, a pilot scale experiment was carried out to evaluate an integrated anaerobic/aerobic treatment for removal of BOD5 and COD, also to reduction of hydraulic retention time by considering optimum removal efficiency. The pilot was an anaerobic/aerobic bioreactor type under continuous-feeding regime based on a central composite design. The pilot was studied in different retention time and aeration was carried out between 5-15 hours. According to different retention times for COD removal efficiency, 24 hours was selected as optimum hydraulic retention time, that it is comparable to those obtained for 48 hours and over in plant roughly and could remove COD and BOD in acceptable ranges, results showed that average removal efficiency for BOD5 were 63.86 and 83.99 percent in aerobic and anaerobic phases, respectively. The average removal efficiency for COD was 76.5 and 74.35 percent for anaerobic and aerobic sections, respectively. The average removal efficiency for BOD5 and COD in this integrated aerobic-anaerobic pilot 95.24 and 94.8 percent, respectively.
M. Khast, M. Hesam, A. Hezarjaribi, O. Mohamadi,
Volume 24, Issue 1 (Spring 2020)
Abstract
Due to the increasing number of small crops, the system of irrigation without a pump can be an economical way. Therefore, in this research, the effects of the type of droplet and the height of water supply system utilization on the characteristics of water distribution (discharge, dispersion uniformity coefficient (CU) and coefficients of variation of discharge) were investigated. In this research, the pressure functions of 1, 2, 3 and 4 meters and three irrigation repeats were investigated; also, the discharge characteristics of jet pots of 2 and 8 nozzles, easy dripper and netafim were addressed. The results indicated that at 1 m pressure, drippers of pots of 2 and 8 nozzles with the uniformity coefficients of distribution were equal to 89.39 and 99.30%, and the discharge rate was 3.60 and 3.62 liters per hour at a pressure of 2 m. An easy-drain drip with a discharge rate of 3.85 L / h and a uniform distribution of 99.44%, at a height of 3 and 4 m, the droplets of the netafim with an outlet discharge were 3.87 and 3.97 liters per hour and the uniformity coefficients of 99.32 and 99.47 percent had the best broadcast conditions. According to these significant differences (P <0.05), it can be concluded that at pressures less than 2 m of jar droplets and at more than 3 m, netafim and Easy Dipper types could have better leakage due to pressure regulators. In general, each of the four types of emitters produced a uniform dispersion and the optimum discharge at different pressures.
Omid Mohamadi, M. Hesam, Kh. Ghorbani,
Volume 26, Issue 1 (Spring 2022)
Abstract
- Due to many problems in the field of water supply, no study has been done on atmospheric water extraction devices. The objective of this research was to optimize the control parameters and the amounts of water produced from a physical model designed and built by the team including two-phase (refrigeration collector and sponge collector) in different atmospheric conditions were investigated. First, the effect of the sponge filter on the amount of water obtained, then the pilot in different weather conditions were studied to obtain optimal conditions. The suctions of 450 to 1400 rpm were applied at each humidity and temperature. In all the mentioned cases, the temperature of the device was studied at 2, 4, and 6 degrees below the dew point. Results showed that the sponge filter can increase the water produced by up to 15%. The first evaporator produced more water than the second evaporator. The optimal air suction speed inside the device depends on the relative humidity and temperature values. For the first and second evaporators, temperatures below 4 °C and 6 °C are optimal, respectively, and with increasing absolute humidity, the optimum suction speed increases. Parameters such as airflow velocity, number of collectors, temperature difference with dew point, and moisture absorption levels were influential in the amount of water produced. According to the qualitative study, the obtained water has a desirable quality for use in sensitive applications.
