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101.
Journal of Crop Science and Biotechnology - Wheat is the most important food on earth. Therefore, to produce high-quality products with efficient utilization, the micronutrient groups are needed....  相似文献   
102.
Twelve wheat varieties were studied for their phytic acid, calcium, iron, zinc, copper and phosphorus contents, which respectively ranged between 114–166, 25.1–53.5, 3.41–5.55, 0.71–3.00, 0.65–1.32 and 298–314 mg/100 g. The molar ratios as Ca:Phy, Phy:Fe, Phy:Zn, Phy:Cu were found to be 0.14–0.29, 1.96–3.86, 5.11–20.5 and 13.0–23.9, respectively. Significant dephytinization, ranging between 35.3 and 69.3% in different varieties, was achieved on exogenous enzymatic treatment. Enzymatic dephytinization in the in vitro simulated gastrointestinal digestion resulted in significant increase in the bioavailability of essential minerals. The increase in bioavailability of calcium, iron, zinc and copper on exogenous enzymatic dephytinization ranged between, respectively (x-folds): 1.30–1.96, 1.11–1.52, 1.22–1.78 and 1.11–1.73.  相似文献   
103.
This study was designed to examine the main effects and interactions of time, presence of antibiotics, and type of sperm activators on the fertilization capacity (eyeing rate) of refrigerated semen of rainbow trout, Oncorhynchus mykiss. The semen samples were stored in the presence or absence of 250 IU ml?1 penicillin and 250 μg ml?1 streptomycin sulfate. Freshwater and a saline solution were used as sperm activators. The semen samples were stored at 2–3°C and fertilized after 0, 6, 8, 12, 19, and 25 days of storage. Fertilizing capacities of semen samples stored in the presence of antibiotics (63.8 ± 5.6%) were significantly (p < 0.05) higher than those stored in the absence of antibiotics (46.2 ± 6.7%). Also, the fertilizing capacities of stored semen samples activated using saline solution (70.7 ± 5.7%) had significantly (p < 0.05) higher values than those activated using freshwater (39.3 ± 5.9%). Semen samples stored in the absence of antibiotics completely lost fertilizing capacity within 19 days of storage. After 25 days of storage in the presence of antibiotics, induction of fertilization using freshwater and saline solution resulted in 0% and 79.8 ± 1.7% fertility, respectively.  相似文献   
104.
Cobalt ferrite nanocrystals were prepared from an aqueous solution containing metal nitrates and various of concentrations of poly(vinyl pyrrolidone), followed by calcinations temperature. X-ray diffraction (XRD) analysis was performed to determine the degree of crystallinity of the ferrite nanoparticles. By transmission electron microscopy (TEM), the morphology and average particle size of the cobalt ferrite nanoparticles were evaluated which had good agreement with XRD results. Fourier transform infrared spectroscopy (FT-IR) suggested the presence of metal oxide bands in all samples as well as the effective elimination of organic constituents after calcinations. Vibrating sample magnetometer (VSM), was utilized to evaluate the magnetic properties of the cobalt ferrite nanoparticles.  相似文献   
105.
Plants’ tolerance to salt stress is different among species, nevertheless, mineral nutrition might also affect it. A greenhouse experiment was conducted to evaluate the effect of Zinc (Zn) on salinity tolerance using a sigmoid response model in two wheat (Triticum aestivum L.) genotypes ‘Falat’ and ‘Bam’ with different salinity tolerances. The treatments consisted of three Zn rates (0, 5 and 10 mg Zn kg?1) and five levels of soil salinity (1.1, 6.5, 12.3, 18.7 and 25.1 dS m?1). The results showed that dry weight of straw and grain decreased, as salinity increased in both genotypes although this decrease in ‘Falat’ genotype was higher than that of ‘Bam’ genotype. Application of 10 mg kg?1 Zn increased the dry weight by 25% (straw) and 32% (grain) in ‘Falat’ but 67% (straw) and 60% (grain) in ‘Bam’ as compared with the absence of added Zn. According to the fitted function, in the absence of Zn, grain production began to decline at ECe-values of 4.7 dS m?1 in ‘Falat’ genotype, and 7.5 dS m?1 in ‘Bam’ genotype. Application of Zn led to a decrease of salinity tolerance in ‘Falat’ genotype, but an increase in ‘Bam’ genotype. The study found that Zn application under saline conditions, depending on genetic differences of wheat genotypes, would have different effects on their tolerance to salinity.  相似文献   
106.
This study assessed the changes of plasma vitamin A, E, and C and the lipid peroxidation status of sheep during breeding and pregnancy under drought conditions. The study was conducted on 105 cross-bred fat tailed ewes, 3–5 years old with body condition scores (BCS) of 2.5 to 3.5. The ewes were grazing on medium-to-low quality forages during summer and low quality forages within the succeeding months and had ad libitum access to a mixture of alfalfa hay (40%) and wheat straw (60%) in the afternoons. From 3 weeks before breeding till 1 month after the introduction of rams, 300 g of barley grain/head/day was offered to the ewes and then the supplemental grain was reduced to 100 g/head/day. For better synchronization of estrus cycles in ewes, they were isolated from the rams for at least 2 months and then kept in close proximity of the rams for 1 week before the introduction of the rams to the ewe flock. Then, whole blood samples were collected on days 1, 7, 21, and 120 after ram introduction. Vitamins A, E, and C were measured in plasma. Malondialdehyde (MDA) was measured in the hemolysate as a biomarker of lipid peroxidation. Plasma progesterone (P4) was measured in the samples of day 120 for assessing pregnancy status of the ewes. Vitamins A and C showed continuous and significant declines (P < 0.05) through days 1 to 120. Vitamin E declined only during the first 21 days of the study and remained almost constant till day 120. MDA concentration increased significantly at day 21. An elevated concentration of MDA was also detected at day 120. The difference between days 21 and 120 was not significant (P > 0.05). A positive correlation between vitamins E and C was detected at day 120 (r = 0.349, P < 0.01). Age and BCS did not affect the patterns of changes. Assuming that the ewes with P4 concentrations ≥2.5 ng/ml were pregnant, 95 out of 105 ewes (90.5%) were pregnant at day 120 of the study. Under the conditions of the present study with medium-to-low quality pastures as the main sources of feed, ewes of various ages and body conditions may suffer from oxidative stress during breeding and pregnancy.  相似文献   
107.
Maedi-visna (MV) is an important slow viral disease of sheep leading to a progressive lymphoproliferative disease. It affects multiple organs primarily the lungs, where it causes interstitial pneumonia (maedi). In this study, the lungs of 1,000 sheep carcasses were grossly inspected and those suspected to have maedi were studied at histopathological and molecular levels. A polymerase chain reaction (PCR) technique that amplified a 291-base pair DNA in the long terminal repeat (LTR) sequence of MV provirus was conducted on all the 50 suspected lungs together with 10 normal appearing lungs as controls. Amplicons of the expected size were detected in 11 (n = 11/50) suspected sheep, and one of the 10 control sheep. Histopathologic study of the pulmonary lesions of all 11 (n = 11/11) positive sheep showed MV lesions, including hyperplasia of the perivascular and peribronchiolar lymphoid cells, interstitial lymphoplasmacytic infiltration and smooth muscle hyperplasia and the histopathologic findings were correlated with PCR results. In contrast, the tissue sections of control animals were almost normal at histopathological level; however, PCR technique demonstrated that one of them was affected by maedi. This study showed that the LTR-PCR had high specificity and sensitivity in diagnosis of this viral infection. This study is the first to evaluate the prevalence of MV virus infection in sheep in Iran.  相似文献   
108.
Considering increasing rate of Iran population and consumption of wood panels, the authors investigated the per capita consumption of wood panels during the years from 1997 to 2007. The exponential smoothing method was used to obtain a per capita consumption pattern of wood panels in Iran for estimating demand of wood panels by the year of 2012. Results show that the consumption of particleboard, fiberboard, and medium density fiberboard in Iran will increase by 33%, 72% and 107 %, respectively, by the year of 2012; however, the consumption of plywood will increase only by 7% by 2012. The deficient amount of wood panels in Iran is estimated over 1400000 m3. The results of this study provide the technique reference for planners of wood panel industries in Iran in capital investment decisions.  相似文献   
109.
A model of supplying poplar wood for Iranian paper & wood factories   总被引:2,自引:2,他引:0  
Majid Azizi 《林业研究》2008,19(4):323-328
The objective of this research is to design a method for an appropriate alternative to supply poplar wood as raw material for wood and paper factories in Iran.Due to the destruction of the forests and lack of proper plantation,replacement of the forest wood by the fast growing wood is vital to satisfy all requirements of these factories.A hierarchy was used to prioritize benefits,opportunities,costs and risks (BOCR) using the Analytic Hierarchy Process (AHP) ratings approach.To evaluate the "control criteria" of the system,a control hierarchy was also created and prioritized by applying the Analytic Network Process (ANP).A total of four major control criteria in the system are prioritized where each one controls a network structure evaluated by using ANP.The final synthesis results of the system showed that internal poplar tree farming supplied by the forest product factories was the best choice among three potential alternatives (factory procurement,external procurement and mix procurement).  相似文献   
110.
One goal in the face of drought stress conditions is to increase growth and yield through the reduction of negative effects of stress. Vermicompost can play an effective role in plant growth and development and in reducing harmful effects of various environmental stresses on plants due to its porous structure, high water storage capacity, having hormone-like substances, plant growth regulators, and high levels of macro and micro nutrients. This study considered the physiological, biochemical, and photosynthetic responses of the chickpea to different combinations of vermicompost and water stress in a greenhouse environment. Two factors were involved, addition of vermicompost to soil at four ratios: control (100 wt% (weight percentage) soil); 10 wt% vermicompost+90% soil; 20 wt% vermicompost+80 wt% soil; 30 wt% vermicompost+70 wt% soil weight percentage, and treatment of water stress at three levels including 75, 50, and 25% of field capacity. The results showed that vermicompost had a significant effect on all traits under stress and non-stress conditions. Application of vermicompost in soil, especially at the levels of 20 and 30 wt% significantly increased all studied traits under non-stress conditions. Under moderate stress conditions, vermicompost at 30 wt% treatment resulted in a significant increase in the photosynthetic pigments, CO2 assimilation rate, internal leaf CO2 concentration, transpiration, the maximal quantum yield of photosystem II (PSII) photochemistry (Fv/Fm), concentrations of Ca and K in root and leaf tissues, proline and soluble protein contents in root tissues. Peroxidase (POX) and catalase (CAT) enzyme activities decreased significantly with increasing proportions of vermicompost, but the activity of superoxide dismutase was not significantly different. In conclusion, the above results showed that vermicompost fertilizer had a positive effect on physiological, biochemical, and photosynthetic responses of chickpea under non-stress and moderate stress conditions, but no positive effect was determined under severe water stress.  相似文献   
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