Showing 7 results for Naghavi
H. Naghavi, M. A. Hajabbasi, M. Afyuni,
Volume 9, Issue 3 (fall 2005)
Abstract
The objective of this study was to evaluate effects of cow manure on soil hydraulic properties and bromide leaching in a sandy loam soil (coarse loamy mixed, Typic Torrifluvents). Manure was applied at 0, 30, and 60 tha-1 at three replications in a completely random design. Three months after manure application potassium bromide (KBr) at rate of 300 Kg ha-1 Br was uniformly applied on the surface. Soil bulk density, porosity, organic matter, and soil moisture at18 levels of matric potentials were determined. Soil samples to the depth of 105 cm at 15-cm increments were collected after 100, 200 and 400 mm of irrigation. Soil bulk density, porosity, organic matter content, and soil moisture at different levels of matric potential increased significantly with manure application. Manure application also significantly affected the hydraulic parameters. Bromide leaching was significantly lower in plots with manure application and the greatest leaching occurred at the zero manure application treatment. The center of mass evaluation indicated a relatively similar result with measured values.
Gh. Azari Takami, M. Amini, M. R. Naghavi,
Volume 10, Issue 2 (summer 2006)
Abstract
The masculinization effects of 17α-methyltestosterone were investigated on the two developmental stages of guppy (Poecilia reticulate), namely, newly born fry and gravid females. The first group was treated with two doses of androgen, (30 and 60 mg/kg food), each for a period of 15 and 30 days and the second group (gravid females) was treated with the food doses of 400, 450 & 500 mg/kg in a 10 day duration prior to parturition. After three months, the first group masculinization ratio of 62.14% was attained only in 60 mg/kg at three-day long treatment and other treatments had no significant effect on masculinization. In this group all the treated fish developed male secondary sexual characteristics after 3 or 4 weeks. However, the above-mentioned characteristics disappeared gradually when hormone therapy was stopped. In the second group, all the treatments were significantly different from control group. 450 and 500 mg/kg treatments had the highest masculinization percentage (90.82 and 97.07, respectively) but the differences were not significant. Also there were 9.18% females in 450 mg/kg treatment and 2.93% intersex in 500 mg/kg treatment. But the so-called group mortality was higher and fecundity lower than those in the control group. Finally, it should be noted that hormonal treatment had not any significant effect on masculinization of newly born fry and with the regard to the effect of 450 mg/kg treatment on masculinization and mortality percentage, it can be introduced as the best treatment.
A. Baghizadeh , A. Talei, M.r. Naghavi, M. Haji Rezaei,
Volume 12, Issue 43 (spring 2008)
Abstract
In order to estimate the number and inheritance of controlling genes for grain yield and some of the related traits in barley, Afzal and Radical varieties along with their F1, F2 and F3 generations were planted in a randomized complete block design with three replications. Head weight, head length, number of heads, number of spikelets, awn length, hundred grain weight, grains per head, straw yield per head , harvest index and grain yield in different generations were recorded. Analysis of variance indicated that mean squares of generations were statistically significant for all the traits. Then, generation mean analysis was performed for all the traits. Based on the results, additive and dominance effects played roles in controlling awn length. For the other traits besides the aforesaid effects, epistasis effect was also significant. Also, results indicated that dominance variance had the most important role in controlling the inheritance for traits. The average broad sense heritability for all the traits was estimated between %69 - %89. The number of genes for all traits was estimated to be between one and six.
S.r. Monfared, A. Hosseinzadeh, M. Mardi, M.r. Naghavi, S.m. Pirseyedi,
Volume 12, Issue 45 (fall 2008)
Abstract
The genetic diversity of major crops, including durum wheat, has suffered an overall reduction with time. The knowledge of patterns of genetic diversity enhances the efficiency of germplasm conservation and improvement. In this study, 87 Iranian landraces of Triticum turgidum var. durum originating from different geographical areas of Iran, along with 21 durum cultivars from ten countries were evaluated using ten primer combination SSAP markers. Retrotransposons are mobile genetic elements that transpose via RNA mediation. They have wide distributions in genome because molecular markers have been designed based on them in recent years. SSAP markers BARE-1,Thv19, Tagermina and Tar1 were also used. Thv19M+ACA primer combination had the most polymorphic band in both landraces and cultivar durum wheats. Approximately 26.7 % BARE-1 bands were polymorphic in landraces.Thv19 showed a polymorphism level of 51.5%, and Tar1 and Tagermina displayed polymorphism levels of 32.8% and 27.2%, respectively. The amount of polymorphism in the studied cultivars for retrotransposons BARE1, Tagermina, Thv19 and Tar1 were 24.4%, 24.3%, 51.5%, 28.5%, respectively. This results show that Thv19 and Tar1 have more transpositional activity in the evolutionary process. Finally, Dendrogram was constructed to use algorithm UPGMA and Dice similarity coefficients.
B Siahsar, A Taleei, A Peyghambari, M Naghavi, A Rezaee, Sh Kohkan,
Volume 13, Issue 47 (4-2009)
Abstract
In order to map the genomic regions affecting barley forage quantity and quality, two experiments were conducted with 72 doubled haploid lines and their two parents (‘Steptoe’ and ‘Morex’), at the Research Farms of the Faculty of Crop and Animal Sciences, University College of Agriculture and Natural Resources, University of Tehran and Agriculture and Natural Resources Research Station of Sistan, in 2007. The experiments were arranged in a randomized complete block design with two replications. Each plot consisted of six rows that were 3m in length and spaced 25cm apart. QTL analysis was conducted by Composite interval mapping (CIM) method separately for each trait in each location. The main effect of genotype was high significant for all the studied traits. Transgressive segregation in both directions (positive and negative) was observed for all the studied traits. There was a negative relationship between forage qualityrelated with quantity-related traits. Thirty-three QTLs controlling different studied traits were identified. Phenotypic variance explained by these QTLs varies from 7.07 to 39.04%. Highest LOD scores were obtained for the leaf to stem ratio on chromosome 2H. QTLs of forage quality (total digestible nutrient, dry organic matter digestibility, leaf to stem ratio, seed to forage ratio and number of tiller per plant) and quantity (plant height, forage wet and dry matter) indexes were found on chromosomes 1H, 2H, 3H, 4H, 5H, 6H and 7H. Most of mapped QTLs appear to be fairly stable between locations and can become candidates for marker-assisted selection.
H. Naghavi, M. Hosseini Nia, Sh. Karimi Googhari, M. Irandost,
Volume 16, Issue 61 (fall 2012)
Abstract
Knowing about the way water is distributed in the soil is essential for designing and managing the Subsurface Drip Irrigation systems (SDI). Since carrying out experiments to recognize the form of moisture distribution in the soil is too complicated and time-consuming, using numerical simulations can be an efficient, effective substitute method to design these systems. One of these models is HYDRUS-2D, which is able to simulate the movement of water, heat and solute in saturated and unsaturated conditions in soil. This research aims to figure out the extent to which the HYDRUS-2D model is able to estimate wetting pattern in soil around a dripper. The simulations’ findings were compared to the data gathered from the field, including SDI system in different irrigation times, and 72 hours after irrigation. Moreover, the rates of error were measured for all points and distances from the dripper in all times of irrigation and also beyond that. The results indicated that the model can simulate the changes, trend similar to what happened in the soil profile. However, it estimated the rate of soil moisture with higher errors in those points in which the wetting took place, with the maximum error rate being RMSE= 0.05 per every 1.5 hours after irrigation starting point in the depth of 30 centimeters where dripper is placed. Also, with an increase in the irrigation time, and soil moisture evening which resulted from redistribution of moisture, the model resulted in better estimations. 72 hours after finishing the irrigation, the estimates were closer to real figures with an average error estimate of RMSE= 0.002.
H. Naghavi, A. Sabbah, M. Amirpour Robat, F. Nourgholipour,
Volume 22, Issue 2 (Summer 2018)
Abstract
This study was conducted based on a randomized complete block design and a factorial experiment with three replications in regions to investigate the effect of different rates and times of nitrogen on the quantitative properties of safflower. The first factor was different nitrogen rates including 0, 60, 120 and 180 kg ha-1 , and the second one was nitrogen application time including seed sowing, rosette and the before flowering stage; these were 1-0-0, 1/3-2/3-0, 2/3-1/3-0 and 1/3-1/3-1/3 with the Goldasht variety. The results showed that nitrogen rate had a significant effect on all studied traits. Nitrogen application time also had a significant effect on capitulum number and yield at p>0.99 and on the length of plant, nitrogen adsorption, agronomic efficiency and apparent recovery at p>0.95. So based on the results, the recommended consumption of 60 kg/ha N was split into three equal amounts at the time of planting, rosette and flowering or 1/3-2/3-0, in Kerman area.