Showing 1096 results for Ro
M.s Tadaion, Gh Moafpourian,
Volume 13, Issue 47 (4-2009)
Abstract
In arid and semi arid regions with high boron content in irrigation water, boron toxicity is a considerable problem. Critical levels of boron in irrigation water variy between 1 and 10 mg/l for sensitive and resistant plants, respectively. In southern parts of Iran especially large citrus production region as Jahrom and Giroft cities, high boron content in irrigation water at toxic levels in most of the region has been the restricting factor for citrus yield increase and for citrus trees exposed to intensive deficiency of potassium and micronutrients like iron, zinc and magnesium. In this experiment, the separate effects of citrus rootstocks including Macrophylla (Citrus macrophylla Wester), Volkamer lemon (Citrus volkameriana), Sour orange (citrus aurantium), Sour lime (Citrus aurantifolia Swing) and their combination with ‘Valencia’ orange, ‘Washington navel’ orange, ‘Jahrom local’ orange, red pulp orange (‘Moro’) as scions on boron uptake were studied. The experiment was conducted as factorial arranged in randomized complete block design with 5 replications and 2 trees per plot in Jahrom Agricultural Research Station for 4 years. According to experimental results, the highest level of boron uptake belonged to ‘Volkamer’ lemon and the lowest to ‘Macrophylla’ rootstocks. Although, Sour orange rootstock had the medium level of boron uptake, but the leaf boron concentration of grafted cultivars on it was clearly very high. In comparison with other rootstocks, interaction between ‘Macrophylla’ rootstock and ‘Valencia’ orange, ‘Washington navel’ orange and red pulp orange (Moro), except ‘Jahrom’ local orange as scions, caused a significant decrease to leaf boron concentration.
S Barati Ghahfarokhi, S Soltani, S.j Khajeddin, B Rayegani,
Volume 13, Issue 47 (4-2009)
Abstract
To investigate land use changes, Qale Shahrokh basin (15098.1 ha area) was selected. Satellite images of Landsat sensors (MSS, TM and ETM+) were used. After improvement and different enhancement analysis of images such as FCC, PCA, the study area was checked using GPS and topographic maps (1:50000) and other information. Land use units were determined using classified random sampling method. Maps accuracy was assessed after performing different classifications. Final land use maps of 1354, 1369, 1381 years were produced using a hybrid method with fine accuracy. Trend of land use changes was investigated during the study periods. Results showed that during the first period (1354), most area of land use was rangeland with sparse vegetation cover (%41.6) and least area was irrigated farming (1.5%). Also, during the second period (1354-1369) most area of land use was rangeland with sparse vegetation cover (%43.4) and least area was irrigated farming (4.1%). During the third period (1369-1381), the maximum area of land use was dry farming (%35.6) and minimum of area was irrigated farming (7%). Maximum land use change was related to rangeland with medium vegetation cover. They were changed into dry farming and rangeland with sparse vegetation cover during 1354 to 1369. During 1369 to 1381, maximum land use changes occurred on poor rangeland with sparse vegetation cover and rangeland with medium vegetation cover was changed into irrigated and dry farming.
A Parsakho, S.a Hosseini, M Lotfalian, H Jalilvand,
Volume 13, Issue 47 (4-2009)
Abstract
Forest roads must be constructed according to technical standards and guidelines which have been published by the scientific and operational organizations. Recently, hydraulic excavators have been used beside the bulldozer for excavating the forest roads. Thus, it is necessary that their ability in construct of standard cross sections be compared. This study was conducted in Lattalar forest which is located south of Sari city (Mazandaran Province). 60 cross section samples were randomly selected for each machine in slope classes of 30-40, 40-50, 50-60 and 60-70%. Then, cross sections were taken by niveau and clinometer. The results in different slope classes showed that the hydraulic excavator and bulldozer had no significant effect on cut and fill slopes length and gradient. Roadbed width in bulldozer construction area was more than the hydraulic excavator at probability level of 1%. Also, there was a significant difference between the hydraulic excavator and bulldozer earthworking width in slope classes of 30-40 and 40-50% at probability level of 5 and 1%, respectively, whereas this difference was not significant in other slope classes. Finally, the average standard cross sections for hydraulic excavator and bulldozer were 89.96 and 84.81%, respectively.
A Gharghni, A Talei, Z Zamani, M Fatahi Moghadam, H Haj Najari, S Gardiner,
Volume 13, Issue 48 (7-2009)
Abstract
A population of offspring from a cross between ‘Golden Smoothee’ × ‘Shafi Abadi’ apple which was developed by two methods of controlled pollination (with and without covering after controlled pollination) was used to investigate the inheritance of microsatellite alleles and the necessity of covering in controlled pollination of apple. DNA was extracted from 60 seedlings (30 from each method) as well as corresponding parents and the probable source of unwanted pollen. Four microsatellite loci (CH03d12, CH03d07, CH04a12 and CH03c07) which were polymorphic among parents were selected and their florescent primers were prepared. DNA amplification was carried out using different colored florescent primers, and alleles size were determined using ABI377 automatic gene sequencer and Gene Scan Software version 2.0 according to internal standards. Results showed that all seedlings shared one allele at each locus with each parent indicating their hybrid and true to type nature. There were no differences between two methods of controlled pollination in terms of unwanted pollination and there were no off type seedling originating from unwanted pollen source. Allele distribution among the progenies showed their co-dominant mode of inheritance, and no significant difference with Mendelian co-dominant ratio (1:1:1:1) was observed using chi square (x2) test. These results showed that there was no need for covering after controlled pollination of apple at least for less sensitive cases such as cultivar breeding which takes lots of time and cost for controlled pollination of many flowers in a limited time span. Results also showed the importance and potential of microsatellite loci in detecting parent-offspring relationship prior to inheritance study of characters and alleles, bulk segregation analysis, gene and linkage map and historical reconstruction of fruit tree pedigree.
A Esfahani, A Hoseyn Zade, J Asghari, M Naghizadeh, B Rabiee,
Volume 13, Issue 48 (7-2009)
Abstract
In order to evaluate the effects of sulphur fertilizer sources and amounts on growth indices and yield of peanut (Arachis hypogaea L. CV. NC2), a field experiment was conducted in Bandar Kiaashahr, Guilan province, Iran in 2004. The experiment was laid out in a factorial arrangement with two factors including sulphur sources (gypsum and single super phosphate) and sulphur rates (0, 30, 60 and 90 kg.h-1) in a completely randomized block design with three replications. Results showed that sulphur application greatly enhanced peanut growth and yield. The application of 90 kg.h-1 sulphur (in both forms) performed significantly better than the rest. The highest pod yield and grain yield were obtained in 90 kg.h-1 sulphur in gypsum form (6400 and 5200 kg.h-1, respectively). The highest LAI (6.6), CGR (20.2 g.m-2.12GDD-1) and PGR (16 g.m-2.12GDD-1) were obtained in 90 kg sulphur in the form of gypsum after 1142, 1142 and 1289 of accumulation, respectively. According to the results of the present experiment, it could be concluded that sulphur may considerably increase peanut grain yield and yield components. Thus, it could be expected that the application of 90 kg sulphur per hectare in the form of gypsum may result in better growth indices and higher grain yield of peanut.
S Kamli, O Alishah, N Babaian,
Volume 13, Issue 48 (7-2009)
Abstract
To assess adaptability and stability of seed cotton yield in promising cotton genotypes, eight cultivars of cotton (Gukorova, Nazeli–84, Khordad, No: 200, Crema, Tabladila, Beli Izovar and Sepid), along with two controls (Sahel and Varamin), were studied in a completely randomized block design (RCBD) with four replications in six regions of Golestan and Mazandaran provinces in two successive years (2005 & 2006). Combined analysis of variance was done and means comparison of yield was conducted based on Duncan's multiple range test. Sepid, Beli Izovar, Varamin and Khordad varieties were superior for yield, earliness, boll weight and boll number, respectively. The result of combined variance analysis showed that, there are significant differences between genotypes and genotype × environment (G.E) interaction effect. Because of significant G.E interaction effect univariete stability parametric and non-parametric stability methods were used to determine genotype stability. The results of varied methods were different. The 43200 and Sepid cotton cultivars had a specific adaptation and were suitable cultivar for fertile lands in north of country, because of good reaction to production high yield. In contrast, Sahel cultivar with lowest yield had broad stability with non-fertile regions. Overall, three genotypes (Khordad, Tabladila and Gukorova) were determined with suitable stability and moderate yield (general stability) for most locations in north of country.
Gh Dehghani, F Malek Shhi, B Alizadeh,
Volume 13, Issue 48 (7-2009)
Abstract
Canola (Brassica napus L.) as one of the oilseed crops has recently received lots of attention due to its suitable oil quality and high oil percentage. To evaluate the effect of water deficit stress on canola genotypes with regard to yield, drought tolerance quantitative indices and identify drought tolerant genotypes, an experiment was conducted in research farm of seed and plant improvement Institute (Karaj) using completely randomized block design with four replications, and 25 genotypes under two stress and non stress conditions. Genotypes were evaluated regarding drought tolerance. Drought tolerance quantitative indices include MP, GMP, STI, SSI and TOL. Result of variance analysis showed significant differences among genotypes as regards all indices and seed yield of genotypes in both conditions at 1% probability level. MP, GMP and STI indices were selected as the best indices for selection of tolerant genotypes in regard to analysis of correlation between seed yield in two stress and non stress conditions and drought tolerance indices. Results indicated that Genotype Vectra was the best genotype, because of its proper mean yield in both stress and non stress conditions. Multivariate biplot figure display showed that MP, GMP and STI indices had high correlation coefficient with each other, and tolerant genotypes were located near tolerance indices. Also results of three dimensional scatter plot and cluster analysis indicated that genotypes Modena, Jura, Eshydromel, Vectra, Dante, Zarfam, Esbetty and Olano were tolerant to drought stress, and genotypes Olpop, GKHelena, RG4504 and Olphi were sensitive genotypes.
A Bahri, Gh Azari Takami, A Keyvan, Gh Vosoghi,
Volume 13, Issue 48 (7-2009)
Abstract
Immunostimulants are one of the important ways to prevent diseases. The vaccination and immune system stimulator and their combination can increase the ability of vaccines in prevention of diseases and improved indexes of growth and survival rates in shrimps. In this research, the separate and simultaneous effects of Ergosan and Vibromax vaccine on the growth factors such as total length and increasing of dry weight and survival rates in three stages of post larvae PL1,PL5 and PL15 in Indian white shrimp (Fenneropenaeus indicus ) were studied. The feeding of vaccine to shrimps was done through Artemia nauplii ( Artemia franciscana) enrichment. The effects of Ergosan (T1) and effect of Vibromax (T2) separately and in combination (T3) along with a control treatment for comparison were studied. Taking into consideration of 4 treatments and 3 replications for each of them, 12 similar vessels were used, which were refilled with 10 liters of water and reserved with 100 larvae in liters in zoa stages and were fed in a completely randomized design. Duration of experiment was from zoa stage to PL15 and in the end of 12, 16 and 25 days they were analyzed for the biometry and determination of survival rates. Results showed that the highest amount of total length (mm) was observed in PL1,PL5 and PL15 stages in T3 (5.26, 6.45 and 18.41) and was a little different from that in T1 (5.28, 6.32 and 17.94) which was significantly different from the control treatment ( 4.91 , 6.09 and 17.36 ) at P<0.05 level. Furthermore, T2 (5.11, 6.07 and 17.44) and control treatment were not significantly different (P>0.05). The highest amount of dry weight (mg) was observed in PL1, PL5 and PL15 stages in T3 (0.296, 0.890 and 2.940). In contrast to the control (0.216, 0.640 and 2.875) it was significantly different (P<0.05).The highest amount of survival rates (%) was observed in T3 (77.33, 76.33 and 80.67) which unlike control treatment (57, 57.33 and 59.67) was significantly different (P<0.05). The use of these two products in a desired feeding program from zoa stage to PL12 could increase the resistance and immunity in post larvae and survival rates and growth factors in shrimps leading to produce suitable post larvae for introducing into the training ponds.
M Sh.zeinodin, M Tadyoni, Sh Dokhani, S Soleymanian Zad,
Volume 13, Issue 48 (7-2009)
Abstract
Exo-polysaccharide (EPS) production by some lactic acid bacteria (starter) during fermentation could affect the physical properties of yoghurt. In this study, at first EPS content and its effects on physical properties of three traditional (S1, S2 and G) and one industrial (I) yoghurt samples were studied. The results showed that there was significant differences in fat content, solid non-fat content, pH, EPS content, viscosity, elasticity and sensitivity to syneresis among samples. Statistical analysis based on a completely randomized design revealed that a significant correlation exists between EPS content and viscosity as well as resistance to syneresis of the samples. Fat content and solid non-fat content of the samples showed no correlation with physical properties of the samples. In the second phase of the study, to remove effects of raw milk composition and to be able to attribute the results to the EPS producing activity of the starter, skim milk was used to produce yoghurt samples using yoghurt samples tested in the first stage only as sources of starter. In these yoghurt samples, there were significant differences between amount of EPS and physical properties of yoghurts. There was also a significant correlation between EPS content and physical properties of each sample.
M Kadivar, N Aghajani, H Hosini, M Kashni Nejad,
Volume 13, Issue 48 (7-2009)
Abstract
Since malting process of barley is greatly affected by the seed endosperm structure, getting information about its anatomical characteristics along with physico-chemical properties would be very important. The aim of this study was to measure length, width, thickness, kernel density, bulk density, porosity, total nitrogen, reducing sugar, diastatic activity, pH and color changes during malting process. Results showed that width, thickness, reducing sugar and diastatic activity of the samples increased over the malting time, whereas kernel density, bulk density and total nitrogen decreased (P<0/05). Scanning electron microscopic examination of barley endosperm revealed a significant relationship between grain total nitrogen and degree of endosperm modification. Because of lower nitrogen content in Sahra malt, more digestion of cell walls and protein matrix of endosperm walls were observed.
F Hosseini, M Habibi Najafi, N Sedaghat,
Volume 13, Issue 48 (7-2009)
Abstract
In this study, two kinds of packages namely tinplate (TP) can and flexible pouch were used for black cherry in syrup. Samples were taken in the same condition in these two packages. Other variables were temperature (4 levels) 4, 23, 35 and 40°C and time (4 levels) 0, 30, 60 and 90 days after preparation of the samples. Samples were digested according to the approved method of AOAC (AOAC, 1990). The total concentrations of Iron, Tin and lead, were determined by atomic absorption spectrophotometer. The mean concentration of Iron, Tin and Lead was 4/858 ppm, 38/459 ppb, 38/459ppb in TP cans and 3/161 ppm, 387/978ppb, 33/993 ppb in flexible pouches. Statistical analysis showed that at %5 probability level, the mean value of Iron content of the product packed in TP cans were significantly higher than the control the same was true about both lead and Tin content. However, this trend was not proved in flexible pouches. Furthermore, temperature had a significant effect on the metal content of the samples.
N Vahedi, M Mazaheri Tehrani, F Shahidi,
Volume 13, Issue 48 (7-2009)
Abstract
In this study, the effect of “Osmodehydrofrozen” fruit addition on sensory, physical, chemical and microbiological properties of concentrated yoghurt and its quality during storage was evaluated. This research was done in two stages. At the first stage, fruit percentage, type and addition time (before and after fermentation) was determined. The results indicated yoghurts containing 10% apple or 13% strawberry, which was added before fermentation had a better quality. Because of high osmotic activity of apple, the synersis was lower in apple yoghurt in comparison with strawberry yoghurt. According to osmotic activity of both fruits, the synersis value was much lower than that of fruit yoghurts, which contained untreated fruits. Taste value was higher in strawberry yoghurt and texture and mouth feel values were higher at low percentages of fruit. The results of the second stage (quality evaluation during storage) indicated that storage had a significant effect on pH, acidity, synersis, taste and texture (P<0.05). In samples which contained apple, coli forms disappeared after 7 days of storage. In samples that contained strawberry, coli forms disappeared after 7 days of storage.
A Farahnaki, S Ansari, M Majzobi,
Volume 13, Issue 48 (7-2009)
Abstract
Crystallization is an important phenomenon that affects some quality attributes such as appearance, texture and shelf life in many food materials. Sugar crystallization is a major challenge for dried fruits such as figs with low moisture levels and high sugar contents. In this study, the effect of glycerol and glucose syrup (DE = 38) on the amount of sugar crystallization in figs with different moisture contents was investigated using X-ray diffraction. The addition of glycerol and glucose syrup increased equilibrium moisture content and reduced sugar crystallization significantly. In the presence of glycerol, sugar crystallization was one third of the control. Glycerol also had greater effect compared to glucose syrup. Changes observed due to the presence of glycerol and glucose syrup could be attrinuted to the hygroscopic behavior of these additives and their ability to keep more water at a specific water activity.
R Amiri Chaijan, M Khosh Taghaza, Gh Montazer, S Minaee, M Alizadeh,
Volume 13, Issue 48 (7-2009)
Abstract
The objective of this research was to predict head rice yield (HRY) in fluidized bed dryer using artificial neural network approaches. Several parameters considered here as input variables for artificial neural network affect operation of fluidized bed dryers. These variables include: air relative humidity, air temperature, inlet air velocity, bed depth, initial moisture content, final moisture content and inlet air temperature. In aggregate, 274 drying experiments were conducted for creating training and testing patterns by a laboratory dryer. Samples were collected from dryer, and then dehulling and polishing operations were done using laboratory apparatus. HRY was measured at several different depths , average of which was considered as HRY for each experiment. Three networks and two training algorithms were used for training presented patterns. Results showed that the cascade forward back propagation algorithm with topology of 7- 13-7-1 and Levenberg-Marquardt training algorithm and activation function of Sigmoid Tangent predicted HRY with determination coefficient of 95.48% and mean absolute error 0.019 in different conditions of fluidized bed paddy drying method. Results showed that the input air temperature and final moisture content has the most significant effect on HRY.
F Khajali, R Bagheri,
Volume 13, Issue 48 (7-2009)
Abstract
The present experiment was carried out to determine the effect of feeding a diluted diet together with avilamycin or probiotics on catch-up growth of broiler chickens. Three hundred day-old chicks (Ross 308 hybrid) were assigned to 4 treatments with 5 replicates based on a completely randomized design. The control group, which met NRC requirements, fed a diet consisting of 2900 KCal/kg ME and 20.8%CP. A diluted diet included 2700 KCal/kg ME and 19.4%CP fed to the negative control group during 7 to 21 days of age. There were two additional treatments with 10ppm avilamycin and 100ppm probiotic, respectively. Feeding the diluted diet resulted in reduced body weight gain (P<0.05). Final body weight was higher in chickens having received avilamycin. Although this difference was insignificant compared with the control, it was significant in comparison with other groups. There was no significant difference in terms of feed intake among the treatments. However, birds which received avilamycin had superior feed conversion ratio to other groups. Birds in the control group had the highest abdominal fat content but the difference was not significant. In conclusion, avilamycin significantly increased body weight gain during catch-up growth though the probiotic caused no significant change.
E Mahdikhani Moghadam, H Rouhani, M Flahi Rastegar,
Volume 13, Issue 48 (7-2009)
Abstract
Sugar beet cyst forming nematode (Heterodera schachtii) is one of the most important pathogens of the sugar beet in Iran. For biological control of Heterodera schachtii, 10 isolates of Trichoderma related to two species T. harzianum and T. virens were examined in laboratory and green house on eggs and cysts for two years. Results obtained from the laboratory assay showed that isolates of Trichoderma parasitized 60% eggs on average. Among them two isolates T. harzianum Bi and T. virens VM1with % 76.18 and %72.55 parasitism, respectively, showed more efficiency compared with the control. In green house, experiments were carried out in autoclaved and non autoclaved soils (field soils) separately with 12 treatments and 3 replications including non infested control (using Ragbi nematicide in field soils experiment), and infested control treated with isolates of Trichoderma using Randomized Complete Design. Then analysis of variance for the bio-control potential of isolates, final population of nematode, fresh and dry root weight, fresh and dry leaves weight inoculated with isolates of Trichoderma was carried out. The results revealed a significant difference (P<0.05) between treatments and control according to Duncan,s Multiple Range Test. T. harzianum Bi and T. virens VM1 decreased population of nematodes, and increased yield in autoclaved and field soils. In autoclaved soils, the two isolates (T. harzianum Bi and T. virens VM1) decreased population of nematodes by %76.68 and %72.65, respectively compared with the control. The Ragbi nematicide, T. harzianum Bi and T. virens VM1 decreased population of nematodes by %81.65, %75.15 and %72.85, respectively compared with the control in field soils experiments.
H Amirnejad, H Rafiee,
Volume 13, Issue 48 (7-2009)
Abstract
Land and its size are important as the most basic factors of production in agriculture .Fragmentation is one of the main problems that rice producers of Mazandaran province are confronted with. Non-efficiency in farm management, inability in effective using of agriculture technology and machinery, and low range productivity of production are all related to land fragmentation. In order to overcome the problems and consequences originating from land fragmentation, specialists recommend the logical solution of land consolidation process, which is a basic strategy for changing the farm size. The purpose of this research was to identify and determine effective factors in land consolidation adoption by rice producers in Mazandaran province by using Logit Regression model. In this study, 150 rice producers from 5 villages have been investigated since 2007. Results show that variables of education, land quality, fragment distance and extension effort (learning programs) are the most important factors in land consolidation adoption by rice producers in this province (Sig=1%) . Also, number of the household and credit support are the next factors affecting in land consolidation adoption (Sig= 5%). I t must be noted that other variable such as age, farmer’s income, children education, experience of rice producers, cultivation area, membership in cooperatives, land situation, number of pieces and technical supports were not significantly involved.
M Kopahi, H Sadat Barikani, M Kavoosi Kelashomi, M Sasoli,
Volume 13, Issue 48 (7-2009)
Abstract
Risk and uncertainty have an important role in determining farmers' goals and their decision making. Risk affects optimal use of inputs and production efficiency. Using production inputs especially new inputs is one of the effective factors in production risk hence, it is necessary to obtain information about inputs use risk in order to find solution to risk management. For investigating effect of inputs use on production risk of rice crop in Gilan province, a quadratic form of production function was applied. Mean production function indicates constant return to scale. Also, risk production function shows increasing acreage and use of fertilizer cause increase in production risk of rice crop. Therefore, consolidating program of rice acreages and policy of paying subsidies to fertilizer input should be managed by considering producers' conditions.
A Esmaeili, F Nasrnia,
Volume 13, Issue 48 (7-2009)
Abstract
Deforestation has been recognized as one of the biggest environmental problems in the world. It is also one of the main elements of land productivity changes and one of the biggest factors which threaten world's environmental diversity. In this study, based on environmental Kuznets theory, factors which may affect deforestation have been investigated. Results obtained from 71 studied countries show that environmental Kuznets curve was not true for them. Population growth helps the speed of deforestation while higher rate of GDP growth decreases its rate. Institutions which help with the improvement of democracy, individual assets, civil right and political liberty can decrease the pressure on natural recourses and deforestation.
M Bakhshoodeh, E Vaseghi,
Volume 13, Issue 48 (7-2009)
Abstract
In this study, marketing situation, problems and services of Dutch Roses was investigated in Isfahan province as a main rose producing region in Iran. In this context, marketing margin, share of marketing agents in marketing margin, marketing cost coefficients and marketing efficiency were calculated and marketing path and marketing services of roses flower including harvesting, transportation, packing, sorting and standardization in major path were investigated. The data used in this study were gathered through completing questionnaires from 38 producers, wholesalers (cut flowers distributors) and retailers (flower sellers) and by interviewing four consulting companies in Dutch Roses production and marketing. The results indicated that 56.5 percent of producers are only engaged with production activities and not exporting flowers to either foreign countries or the other provinces in the country. In the main path, average coefficient of technical efficiency (78.17%) was found to be higher than that of price efficiency (34.67%) and based on the marketing efficiency, 108 Rial value added can be achieved from each 100 Rial marketing services cost..
