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61.
Selenium deficiency in various degrees affects around 15% of the world’s population, contributing to a variety of health problems. In this study, we examined the accumulation and biotransformation of soil applied Se-supplementation (sodium selenite and sodium selenate forms) at different concentrations, along with growth and yield formation of green pea, in a greenhouse experiment. Biotransformation of inorganic Se was evaluated using HPLC-ICP-MS for Se-species separation in the above ground parts of green pea. Results showed 3 mg kg?1 SeIV increased green pea growth biomarkers and also caused an increase in protein content in leaves by 17%. Selenomethionine represented 65% of the total selenium content in shoots, but was lower in pods and seeds (54 and 38%, respectively). Selenomethionine was the major species in all plant parts and the only organic selenium form in the lower SeIV concentration range. Elevating the dose of SeIV (≥30 mg kg?1) triggered detrimental effects on growth and protein content and caused higher accumulation of inorganic Se in forms of SeVI and SeIV. Selenocysteine, another organic form of proteinogenic amino acid, was determined when SeIV (≥10 mg kg?1) was applied in higher concentrations. Thus, agronomic biofortification using the appropriate chemical form and concentration of Se will have positive effects on green pea growth and its enriched shoots and seeds provide a value-added protein source for livestock and humans with significant increased selenomethionine.  相似文献   
62.
The effects of photoperiod (12L:12D and 18L:6D) and feeding frequency (three, four and five evenly spaced daily feedings) of 10% biomass per day during light hours on growth and stress response of Persian sturgeon (Acipenser persicus) fingerlings were evaluated. The interaction between photoperiod and feeding frequency was not significant (P>0.05). Faster growth was observed in fish exposed to an 18L:6D photoperiod (P<0.01). The feed conversion efficiency (FCE) was also better with an 18L:6D photoperiod (P<0.05). Fish fed four and five meals per day grew similarly (P>0.05) and faster than when fed only three meals (P<0.01). The FCE with four or five meals per day was better than with three meals (P<0.05). At harvest, the proximate composition was similar in all treatments (P>0.05). Stress indicators (cortisol, glucose and haematocrit) did not differ between photoperiods (P<0.05). The results showed that 0.9–8.0 g Persian sturgeon fingerlings should be reared with an 18L:6D photoperiod and fed four times per day to obtain good growth and FCE.  相似文献   
63.
Journal of Crop Science and Biotechnology - Nowadays, transgenic plants are considered as an expression system for therapeutic recombinant proteins. One of the approaches to recombinant protein...  相似文献   
64.
Potassium fixation capacity and mineralogical analysis of 24 representative soils, collected from southern Iran, were studied. Potassium fixation analysis was performed by adding six rates of K from 0 to 1000 mg kg?1 soil in a plastic beaker and shaking for 24 h. Mineralogical analysis showed that the clay fractions were dominated by smectite, chlorite, mica, palygorskite, vermiculite and quartz. In general, the studied soils fixed 8.5–55% of the added K. The potassium fixation capacity of the studied soils was significantly correlated with smectite content (r 2 = 0.87), clay content (r 2 = 0.60), cation-exchange capacity (r 2 = 0.79) and NH4OAc-K. Wetting and drying treatment and incubation time had significant effects on K fixation. The average percentage increase in K fixation following the wetting and drying treatment was 24 and 30% for surface and subsurface soils, respectively. The average percentage increase in K fixation with increasing residence time was 79 and 56% for surface and subsurface soils, respectively. Because K fixation is a diffusion process, time and increased concentration of soluble K (because of soil drying) are factors affecting the rate of K diffusion from a soil solution to the interlayer positions of the expansible 2:1 clay minerals.  相似文献   
65.
Crop drought tolerance improvement is one of the most challenging objectives of plant breeding programs. Developing an efficient screening technology and access to genetic variation for the traits contributing toward drought tolerance are major steps in this direction. To go in this quest, an experiment was conducted under controlled condition in a greenhouse. Nine Kabuli chickpea genotypes were grown under well-watered condition (85–90% field capacity (FC)) until start of flowering. Then, the following water treatments were imposed: well-watered, intermediate (55–60% FC), and severe (25–30% FC) drought stress. Physiological and agronomical traits were compared under different water treatments. Drought stress and genotypes interaction was significant in all measured traits, indicating that various genotypes responded differently to drought stress. Among measured traits, electrolyte leakage, stomatal conductance, yield components, and harvest index exhibited the highest variations. Yield components and stomatal conductance showed maximum reduction under drought stress and in susceptible known genotype, ILC3279, reduction reached up to 95%. Principal component analysis indicated that relative water content, photochemical efficiency of photosystem II, and stomatal conductance are the physiological traits with greater contribution toward drought tolerance. Therefore, these traits should be evaluated ahead of many other traits in making selections for drought-tolerant chickpea genotypes.  相似文献   
66.
The release of non-exchangeable potassium from 24 calcareous soils of divergent mineralogy, from southern Iran, was examined. Sand, silt and clay particles were fractionated after dispersion with an ultrasonic probe. Samples were extracted with 0.01 M CaCl2 for 30 successive 2-h periods. The clay fraction released the largest amount of K in each soil. Cumulative K released ranged from 175 to 723, 35 to 128, and 71 to 146 mg kg?1 contributing 20–90, 4–39 and 2–54% for clay, silt and sand fractions, respectively. The lower proportion of K released from sand and silt fractions can be explained by the presence of a high content of CaCO3 and quartz in these fractions. The release kinetics for the non-exchangeable K data showed that parabolic diffusion and power function were the best fitting kinetic models. This indicated that slow diffusion of K from the mica interlayer positions is the main rate-controlling process. Cumulative K released and constant b values of parabolic diffusion model correlated significantly with the mica content of the clay fraction.  相似文献   
67.
Background:Treatment with BMMSCs has anti-inflammatory, tissue regenerative, angiogenic, and immune-stimulating effects. When using as sheets or accumulate, BMMSCs causes the development of neoangiogenesis in damaged skin tissue. Diabetes, a metabolic disorder, can negatively affect many physiological functions, including the process of skin injury repair. This adverse impact may increase the risk of skin surgery. RSF is commonly used in reconstructive surgery. The terminal part of the RSF is often affected by necrosis because of impaired blood flow, which is exacerbated in diabetes. This study investigated the effect of stem cells, applied as accumulated or cell sheets, along with RSF surgery on skin capillaries in STZ-induced diabetic rats. Methods:Thirty male Wistar rats were divided into three groups (n = 10): diabetes-RSF control, diabetes-RSF local applied stem cells (loc-BMMSCs), diabetes-RSF applied stem cells as accumulated or cell sheets (ac-BMMSCs). Two weeks after the STZ injection, RSF surgery and stem cell therapy (6 × 109) were carried out (day zero). Furthermore, stereological methods were used to investigate the capillary patterns among the groups. Anti-CD31/PCAM1 immunohistochemistry was also used for further confirmation of changes in capillary parameters. Results:The results demonstrated that capillaries were protected by MSC sheets in the flap tissue, and the thickness of the epidermal layer was improved, indicationg the possible beneficial effects of MSC sheets on diabetic wound treatment. Conclusion:Stem cells, as ac-BMMSCs, may decrease the levels of wound healing complications in diabetes and can be considered as a cell therapy option in such conditions.Key Words: Neoangiogenesis, Skin flap, Transplantation, Wound healing  相似文献   
68.
In this study, effects of foliar application (with constant 0.2% concentration) of chemical NPK (N20:P10:K20) and organic fertilizers of Biomin (an organic aminochelate fertilizer), Humifolin (a humic acid based fertilizer), Biomin?+?Humifolin, a synthetic macro-micro mixture, soil application of NPK (600?mg.kg?1 of the N20:P10:K20 formulation), and a no fertilizer control were evaluated on growth and quality of chili pepper (Capsicum annuum var annuum) seedlings under greenhouse conditions with cool temperature of 15?±?3?°C. The results showed that most growth and quality traits were best improved by foliar application of Biomin aminochelate followed by Humifolin fertilizer. Higher values for leaf area, leaf number, chlorophyl index, root and shoot biomass, and leaf concentration of soluble sugars, N, K, Ca, and Zn, were attributed to foliar application of Biomin and Humifolin. The mixture of Biomin?+?Humifolin had reduced values of those parameters indicating possible negative interaction when these two organic fertilizers are mixed.  相似文献   
69.
The aim of the present study was to investigate the effects of different salinities (0‰, 6‰ and 12‰) and temperatures (23, 27 and 31 °C) on the food consumption, growth, blood biochemistry and haematocrit of Goldfish. After 45 days of exposure to different salinities and temperatures, Goldfish showed a good adaptation to these salinities and temperatures in terms of blood biochemistry (glucose and triglyceride) and haematocrit. Salinities (0‰ and 6‰) and temperatures (23 and 27 °C) did not affect the weight gain, specific growth rate, final biomass and feed conversion rates, but these parameters were significant (P<0.05) at 12‰ salinity and 31 °C temperature. Plasma total protein levels decreased with the increase in salinity (P<0.05), while they were independent of temperature. In conclusion, Carassius auratus, a freshwater stenohaline fish, showed good growth in saline waters with maximum 12‰ salinity and 31 °C temperature.  相似文献   
70.
The thickness swelling rates of compression molded wood plastic composites (WPCs) prepared from 50% by weight sawdust and 50% by weight virgin and/or recycled plastics (HDPE and PP) were studied. Thickness swelling rates of the manufactured WPCs were evaluated by immersing them in water at room temperature and monitoring thickness changes for several weeks. A swelling model developed by Shi and Gardner (Composites Part A, 37:1276–1285, 2006) was used to study the thickness swelling process of WPCs. The parameter K SR of the model can be used to quantify the swelling rate. The results indicated that composites containing PP had lower equilibrium thickness swelling and also shorter equilibrium time (time to reach equilibrium thickness swelling). The swelling model developed was a good predictor of the hygroscopic swelling process of wood plastic composites. Composites containing PP (virgin and recycled) had higher K SR than those containing HDPE. The minimum and maximum K SR values were observed in composites made of virgin HDPE and a mixture of recycled plastics, respectively. With increasing recycled plastic content K SR linearly decreased.  相似文献   
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