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Taghian M.,University of Agriculture and Natural Resources Ramin | Rosbjerg D.,Technical University of Denmark | Haghighi A.,Shahid Chamran University | Madsen H.,Head of Innovation
Journal of Water Resources Planning and Management | Year: 2014

As a common approach to reservoir operating policies, water levels at the end of each time interval should be kept at or above the rule curve. In this study, the policy is captured using rationing of the target yield to reduce the intensity of severe water shortages. For this purpose, a hybrid model is developed to optimize simultaneously both the conventional rule curve and the hedging rule. In the compound model, a simple genetic algorithm is coupled with a simulation program, including an inner linear programming algorithm. In this way, operational policies are imposed by priority concepts to achieve the optimal water allocation and the target storage levels for reservoirs. As a case study, a multipurpose, multireservoir system in southern Iran is selected. The results show that the model has good performance in extracting the optimum policy for reservoir operation under both normal and drought conditions. © 2014 American Society of Civil Engineers.


Azizi-Shotorkhoft A.,University of Agriculture and Natural Resources Ramin | Rezaei J.,Tarbiat Modares University | Fazaeli H.,Animal Science Research Institute
Animal Feed Science and Technology | Year: 2013

A 28-d experiment was performed to evaluate the influence of replacing dietary corn/barley with molasses at levels of 0 (M0), 50 (M50) and 100 (M100) g/kg dietary dry matter (DM), as energy sources, in the diets containing heat-processed broiler litter (HBL) (240. g/kg DM) in male Moghani sheep. Digestibility, microbial protein supply (MPS), ruminal parameters and blood metabolites were measured. The digestibility of DM and crude protein (CP) in experimental sheep linearly increased (L, P=0.01) as level of molasses enhanced in the diets. Addition of molasses to diet linearly increased MPS (L, P=0.01) compared to sheep fed the control diet. Ruminal pH and ammonia concentrations linearly declined (L, P<0.05) as level of molasses increased in the diet. There was no difference (P>0.05) in ruminal volatile fatty acid concentrations, except a linear increase in the molar proportion of butyrate (L, P=0.02) among the molasses supplemented groups. Blood urea-N linearly decreased (L, P=0.02) in sheep fed molasses compared to the control group. It can be concluded that replacing corn/barley with molasses in sheep diet improved the utilization of the diet containing HBL. © 2012 Elsevier B.V.


Osdaghi E.,University of Agriculture and Natural Resources Ramin | Lak M.R.,Agricultural and Natural Resources Research Center of Iran
Journal of Phytopathology | Year: 2015

A new orange variant of Curtobacterium flaccumfaciens pv. flaccumfaciens was isolated from seeds of common bean cv. Daneshkadeh and Dehghan stored in the seed banks in Khomein Bean Research Station, and field plants (cv. Local Khomein) in Arak, Iran. The pathogenicity of the isolates was confirmed on 5- to 7-day-old seedlings of cv. Daneshkadeh. Marginal necrosis and interveinal chlorosis on first trifoliate leaves were observed 10-15 days after inoculation. Amplification of 306 bp fragment of orange-pigmented strains using CffFOR2- and CffREV4-specific prime pair characterized them as C. flaccumfaciens pv. flaccumfaciens. Although the yellow-pigmented variant of the causal agent was previously reported on cowpea, this is the first report of orange variant of C. flaccumfaciens pv. flaccumfaciens causing bacterial wilt on common bean in Iran. © 2015 Blackwell Verlag GmbH.


Tahmouzi S.,University of Agriculture and Natural Resources Ramin
Carbohydrate Polymers | Year: 2014

Ultrasonic assisted-extraction technique was applied to extract the polysaccharide from Zagros oak (Quercus brantii Lindl). The effects of four independent factors (ultrasonic power (X1: 150-300 W), extraction temperature (X2: 50-90 C), extraction time (X3: 30-90 min), and the ratio of water to raw material (X4: 15-45)) on the extraction yield of polysaccharide from the leaves of Q. brantii Lindl (QBLP) were optimized using response surface methodology. The experimental data obtained were fitted to a second-order polynomial equation. The optimal extraction conditions for QBLP were determined as follows: X1: 205.8 W, X2: 81.9 C, X3: 55.6 min and X4: 23.4. Under these optimal conditions, the experimental yield was 19.42 ± 0.53%, which was well matched with the value predicted by the model 19.61%. The results indicated that polysaccharide has strong scavenging activities in vitro on DPPH and hydroxyl radicals. In addition, the QBLP showed good antimicrobial activity at 1.5-2.5 mg/mL. © 2014 Elsevier Ltd. All rights reserved.


Tahmouzi S.,University of Agriculture and Natural Resources Ramin | Ghodsi M.,University of Agriculture and Natural Resources Ramin
Carbohydrate Polymers | Year: 2014

Box-Behnken design was employed to optimize the extraction conditions for polysaccharides from the leaves of motherwort (Leonurus cardiaca L.). Three independent variables including extraction temperature (60-100 °C), extraction time (60-120 min), and the ratio of water to raw material (20-60) were investigated. The results revealed that the quadratic and linear terms of three factors had strong effects on the extraction yield of polysaccharides from motherwort leaf. The best extraction conditions for the yield of polysaccharide (LCLP) was extraction temperature of 81.4 °C, time of 106.6 min and the ratio of water to raw material of 45.2. Under the optimal conditions, the extraction yield of LCLP was 9.17 ± 0.39%, which was well matched with value predicted by the model 9.26%. The results indicated that the purified LCLP exerted obvious scavenging effects on free radicals in vitro. Furthermore, motherwort polysaccharides could be used as a novel antimicrobial additive. © 2014 Elsevier Ltd.


Zandi-Sohani N.,University of Agriculture and Natural Resources Ramin
Indian Journal of Agricultural Sciences | Year: 2011

The toxicity of essential oil vapours distilled from thyme (Zataria multiflora Boiss), rosemary (Rosmarinus officinalis L.), Savory (Satureja hortensis L.), Penny royal (Mentha pulegium L.) and spearmint (Mentha viridis L.) were tested against adults of cotton whitefly (Bemisia tabaci Gennadius). Insects were exposed at time 3, 6, 9, 12 and 24 hr and the amounts of the essential oils were 2,4, 6 and 8 μl in each desiccator with 41 capacity, corresponding to 0.5, 1, 1.5 and 2 μl/1 air. The essential oil vapours of all five species caused the highest mortality in 2 μl/l air doses and 24hr of exposure time in this species. In general, higher mortality was observed as the doses of essential oils and exposure period increased. The results showed that the essential oil of five aromatic plants have the potential to be used for management of B. tabaci in greenhouse conditions. M. pulegium and M. viridis essential oils caused the highest mortality of B. tabaci adults (78.75 and 78.19%), respectively. The mean mortality caused by essential oils of Z multiflora, R. officinalis and S. hortensis were 69.02, 54.3 and 53.47% respectively.


Zandi-Sohani N.,University of Agriculture and Natural Resources Ramin | Shishehbor P.,Shahid Chamran University
BioControl | Year: 2011

Development, reproduction, and life table parameters of the parasitoid Encarsia acaudaleyrodis Hayat parasitizing Bemisia tabaci Gennadius were studied at constant temperatures in the range of 20-32°C under laboratory conditions. Egg-to-adult developmental time decreased from 20.3days at 20°C to 9.0 days at 32°C. An average of 189.8 day-degrees was required to complete development above the lower threshold temperature (11.5°C). Juvenile survival was 84, 88, 70 and 69% at 20, 25, 30 and 32°C, respectively. Females of E. acaudaleyrodis oviposited means of 34.2, 54.6, 30.6 and 20.1 eggs at 20, 25, 30 and 32°C, respectively, and had a mean longevity of 21.1, 14.7, 10.0 and 9.1 days at the same four temperatures. The intrinsic rate of population increase (rm) at the different temperatures ranged from 0.082 to 0.169, with the highest value recorded at 25°C. These data indicate that E. acaudaleyrodis may be better adapted to intermediate temperatures around 25°C and, therefore, could be a useful biological control agent of B. tabaci during spring and autumn when such temperatures are prevalent in Southwestern of Iran. The result could also be useful in developing a population model for E. acaudaleyrodis under field conditions. © 2010 International Organization for Biological Control (IOBC).


Tahmouzi S.,University of Agriculture and Natural Resources Ramin
International Journal of Biological Macromolecules | Year: 2014

The objective of the present research was to investigate the effect of microwave-assisted extraction (MAE) conditions on the extraction yield, antioxidant properties and antilisterial activities of the polysaccharides from the flowers of viper's bugloss (Echium vulgare L.). The four extraction variables, time (40-100. min), microwave power (200-800. W), temperature (30-70. °C), and the ratio of water to raw material (10-70), were optimized using response surface methodology. The experimental data were matched to a second-order polynomial equation. The optimal conditions for MAE of polysaccharides (EVFP) were time 73.8. min, microwave power 769.2. W, temperature 42.3. °C and the ratio of water to raw material 61.4, where the actual yield of EVFP 25.11. ±. 0.87% was obtained (versus the value predicted by the model 25.36%). The results indicated that EVFP has significant radical (·OH and ·DPPH) scavenging abilities in vitro assay. Moreover, the antilisterial activity was confirmed against four species of Listeria. EVFP, at a concentration of 5. mg/mL, demonstrated great antilisterial properties against Listeria ivanovii and Listeria monocytogenes, with inhibition zones of 10.76. ±. 0.32. mm and 8.64. ±. 0.47. mm, respectively. © 2014 Elsevier B.V.


Tabatabaei S.,University of Agriculture and Natural Resources Ramin
Comparative Clinical Pathology | Year: 2012

The purpose of this study was to determine the values of some metabolites, ions, and enzymes in maternal blood serum and fetal fluids in relation to pregnancy stage in singleton pregnant goats. Gravid uteri of goats were collected from local abattoirs. The allantoic and amniotic fluids as well as maternal blood samples were collected. Fetal age was determined according to crown-rump length by applying the age estimation formula that previously was presented for goat. The pregnancies were divided into five stages as: stage I (0-30 days), stage II (31-60 days), stage III (61-90 days), stage IV (91-120 days), and stage V (121 days to term). With the progress of pregnancy, the biochemical levels of fetal fluids and maternal serum changed as follows: there was a rise of total protein, urea, and creatinine concentrations in fetal fluids and serum; the level of glucose in serum, potassium, and ALK in fetal fluids and calcium and phosphorus in allantoic fluid increased; triglyceride and sodium contents of fetal fluids and serum decreased; glucose in fetal fluids, AST and LDH in serum and allantoic fluid, potassium and ALT in serum, and calcium and phosphorus in amniotic fluid and serum dropped; the values of AST, ALT, and ALK in amniotic fluid remained unchanged; and the levels of cholesterol and LDH in amniotic and allantoic fluids were constant in the whole gestation periods. The serum cholesterol value showed a significant decrease from stages 1 to 2 of pregnancy. But, it was not significant from stages 2 to 5 of gestation. © 2011 Springer-Verlag London Limited.


Zandi-Sohani N.,University of Agriculture and Natural Resources Ramin
International Journal of Tropical Insect Science | Year: 2012

Satureja hortensis and Zataria multiflora (Lamiaceae) essential oils were tested on Callosobruchus maculatus (Fabricius) to evaluate their effects on oviposition deterrence, egg hatching and mortality of adults. To obtain essential oils, dry leaves were subjected to hydrodistillation using a modified Clevenger-type apparatus. The experiments were conducted at 25 ± 1°C and 65 ± 5% relative humidity in dark conditions with five replications for each essential oil. When concentrations of both essential oils were higher, the insecticidal effect on eggs and adults increased and oviposition was more deterred. At the highest concentration (60 Πl/l air) of S. hortensis and Z. multiflora essential oils, 91.2 and 85.4% of adults were killed, respectively. There were no significant differences in oviposition deterrence between the two essential oils. At the highest concentration (4.3 Πl/l air) of S. hortensis and Z. multiflora essential oils, egg mortality was 94.5 and 77.3%, respectively. Probit analysis revealed LC50 for adults and eggs of C. maculatus of 1.50 and 1.13 Πl/l air, respectively, for the S. hortensis essential oil and 1.76 and 2.23 Πl/l air, respectively, for the Z. multiflora essential oil. The results suggest that the essential oils of these aromatic plants can be used as botanical fumigants to protect grains against C. maculatus. © Copyright ICIPE 2012.

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