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51.
Based on the antioxidant properties of essential oils, the effect of thyme, coriander, and rosemary was evaluated on the reduction of peroxidase in white cabbage “Brassica oleraceae var.capitata f. alba” and red cabbage “B. oleraceae var. capitata f. rubra”. To do this, pure, 50, 75, 100 and 200 μl/100 ml concentrations of essential oils were applied in vivo and in vitro of cabbages. Antioxidant activity of the essential oils was compared with that of ascorbic acid. Results revealed that the highest percentage of antioxidant activity was achieved in vitro using a pure concentration of coriander (52.65%) and rosemary (54.64%), and in vivo applying thyme (60.07%) of white cabbage. Applying in vitro pure concentration of coriander (46.39%) and 50 μl/100 ml of rosemary (41.64%), and in vivo 75 μl/100 ml of thyme (42.64%) in red cabbage showed high antioxidant activity. A high reduction of peroxidase was obtained in vitro using of essential oils in red and white cabbages.  相似文献   
52.
The ability of a few soil bacteria to transform unavailable forms of potassium (K) to an available form is an important feature in plant growth-promoting bacteria for increasing plant yields of high-K-demand crops. In this research, isolation, screening, and characterization of six isolates of K solubilizing bacteria (KSB) from some Iranian soils were carried out. The ability of all isolates were tested in three treatments including acid-leached soil, biotite, and muscovite by analyzing the soluble K content after 5 days of incubation at 28 ± 2°C. Identification and phylogenetic analyses were also carried out by morphological, biochemical, and 16S rDNA analyses. Among the six efficient isolates, five isolates belonged to Bacillus megaterium (JK3, JK4, JK5, JK6, and JK7), while isolate JK2 belonged to Arthrobacter sp. The soluble K contents in all isolated-treatments were significantly (< 0.01) higher than the contents in nonbacteria treatment. Herein, isolate JK2 had lower potential for K solubilization (910 mg kg?1) compared with other isolates in acid-leached soils. The six bacterial strains showed higher solubilized K in biotite treatment than other two treatments. Overall, it can be concluded that the isolates belong to B. megaterium are the most efficient KSB under in vitro condition.  相似文献   
53.
Relationships between insulin-like growth factor-I (IGF-I) and thyroxine (T4) and cortisol hormones were studied in female brood stocks of Persian sturgeon [Acipenser persicus; caught from both sea water (SW) and fresh water (FW)] during late stages of sex maturation. A number of biometrical traits were also studied that could represent the reproductive and/or growth states of brood stocks, and the possible relationship between IGF-I and growth was assessed in juvenile Persian sturgeons between 1 and 4 years of age. IGF-I, T4 and cortisol were measured in serum samples using commercially available kits. A four-parameter logistic model test was performed between the standard curves and the sample dilutions for each hormone. Parallelism, linearity and regression coefficients for the linearized standard curves and serial dilutions of samples were not significantly different (P < 0.05). Serum IGF-I levels in the juveniles were higher than those in the SW brood stocks, and cortisol levels in the former were lower than those in both brood stocks (P < 0.05). T4 levels in serum samples of juveniles were below the detectable level. IGF-I concentrations in juveniles were correlated with total weight, total length and fork length, but they did not increase significantly with increasing age from 1 to 4 years old (P < 0.05). Compared with SW brood stock, the FW brood stock was younger, had a smaller girth, smaller polarization index and higher ova diameter (P < 0.05). There were no differences between IGF-I and T4 levels in the two brood stocks, but cortisol levels were significantly higher in the FW brood stock. Percentage of fertilization was correlated with serum IGF-I in both brood stocks (P < 0.05). Our results support a role for IGF-I during the juvenile growth and reproductive physiology in female brood stocks of the Persian sturgeon.  相似文献   
54.
Growing concerns for food security and the alleviation of hunger necessitate knowledge-based crop management technologies for sustainable crop production. In this study, 13 winter bread wheat genotypes (old, relatively old, modern, and breeding lines) were evaluated under three different tillage systems, i.e., conventional tillage (CT, full tillage with residue removed), reduced tillage (RT, chisel tillage with residue retained) and no-tillage (NT, no-tillage with residue retained on the soil surface) in farmer's fields under rainfed conditions using strip-plot arrangements in a randomized complete block design with three replications in the west of Iran (Kamyaran and Hosseinabad locations) over two cropping seasons (2018–2019 and 2019–2020).The main objectives were to investigate the effects of tillage systems and growing conditions on the agronomic characteristics, grain yield and stability performance of rainfed winter bread wheat genotypes.Significant (P<0.01) genotype×tillage system interaction effects on grain yield and agronomic traits suggested that the genotypes responded differently to the different tillage systems. The number of grains per spike and plant height were positively (P<0.0) associated with grain yield under the NT system, so they may be considered as targeted traits for future wheat breeding. Using statistical models, the modern cultivars (“Sadra” and “Baran”) were identified as high yielding and showed yield stability across the different tillage systems. As per each tillage system, genotype “Sadra” followed by “Zargana-6//Dari 1-7 Sabalan” exhibited higher adaption to CT; while cultivars “Jam” and “Azar2” showed better performance under the RT system; and cultivars “Varan” and “Baran” tended to have better performance expression in the NT condition.The increased grain yields achieved in combination with lower costs and greater profits from conservation agriculture suggest that adapted cultivar and NT systems should be evaluated and promoted more widely to farmers in the west of Iran as an attractive package of crop management technologies.In conclusion, variations in the performance of genotypes and the significant genotype×tillage system interaction effects on grain yield and some agronomic traits assessed in this study suggest that the development and selection of cultivars adapted to the NT system should be considered and included in the strategies and objectives of winter wheat breeding programs for the temperate and cold dryland conditions of Iran.  相似文献   
55.
Background:One of the main challenges with conventional scaffold fabrication methods is the inability to control scaffold architecture. Recently, scaffolds with controlled shape and architecture have been fabricated using 3D-printing. Herein, we aimed to determine whether the much tighter control of microstructure of 3DP PLGA/β-TCP scaffolds is more effective in promoting osteogenesis than porous scaffolds produced by solvent casting/porogen leaching. Methods:Physical and mechanical properties of porous and 3DP scaffolds were studied. The response of pre-osteoblasts to the scaffolds was analyzed after 14 days. Results:The 3DP scaffolds had a smoother surface (Ra: 22 ± 3 µm) relative to the highly rough surface of porous scaffolds (Ra: 110 ± 15 µm). Water contact angle was 112 ± 4° on porous and 76 ± 6° on 3DP scaffolds. Porous and 3DP scaffolds had the pore size of 408 ± 90 and 315 ± 17 µm and porosity of 85 ± 5% and 39 ± 7%, respectively. Compressive strength of 3DP scaffolds (4.0 ± 0.3 MPa) was higher than porous scaffolds (1.7 ± 0.2 MPa). Collagenous matrix deposition was similar on both scaffolds. Cells proliferated from day 1 to day 14 by fourfold in porous and by 3.8-fold in 3DP scaffolds. ALP activity was 21-fold higher in 3DP scaffolds than porous scaffolds. Conclusion:The 3DP scaffolds show enhanced mechanical properties and ALP activity compared to porous scaffolds in vitro, suggesting that 3DP PLGA/β-TCP scaffolds are possibly more favorable for bone formation. Key Words: Alkaline phosphatase, β-tricalcium phosphate, Poly(lactic-co-glycolic) acid copolymer  相似文献   
56.
57.
Viral disease of rhizomania is one of the most important diseases of sugar beet all over the world. The disease significantly has reduced the yield and quality of sugar beet, and has imposed high economic loss to farmers. Long-term breeding programs to introduce tolerant cultivars are the only chance of avoiding further yield losses. This study tried to measure and analyze the growth of shoots and roots of rhizomania-tolerant and -susceptible sugar beet with the aim of providing information for modeling of the rhizomania effects on the growth of sugar beet. Growth indices were used for analyzing, quantification, and time-course of sugar beet growth under infested and non-infested soils conditions. A 2-year experiment was conducted using four sugar beet cultivars in 2010 and 2011 in Mashhad, Iran. The results of this study showed that under infested soils, root dry matter and leaf area index of the susceptible cultivars in comparison to tolerant cultivars were lower by 57 and 24%, respectively. In addition, crop growth rate and net assimilation rate of susceptible cultivars were affected by rhizomania and were lower than in tolerant cultivars. On non-infested soil, the difference between dry matter and growth indices of susceptible and tolerant sugar beet cultivars was not significant. Rhizomania decreased green area and photosynthesis capacity and led to lower growth rate and dry matter production. Our study quantified the growth of rhizomania-infested sugar beet plants in comparison with non-infested plants and provided information to be used for modeling of the rhizomania effects on the growth of sugar beet.  相似文献   
58.
Soil application of organic wastes (OWs) can be beneficial for soil quality, depending on the quality of the wastes as well as on the amended soil. We performed a field experiment comparing the effects of two different OWs, an industrial sewage sludge (ISS) and a municipal solid waste compost (MSWC), on the physical, chemical and biological quality of an agricultural soil cultivated with maize in central Iran. The two OWs were mixed into the topsoil of the plots at rates of 15 and 45 t ha?1 (dry matter). The analysis of soil samples taken 31, 74, 132 and 241 days after OW application showed both OW increased organic matter, microbial respiration, and urease activity and decreased bulk density. In contrast, they had opposite effects on water retention and saturated hydraulic conductivity. While the MSWC increased water retention at high saturation and saturated hydraulic conductivity, the ISS decreased them. The negative effects of the ISS on physical soil quality, which may have been due to pore-clogging and hydrophobicity effects, were related to a smaller yield increase in the ISS than in the MSWC treatments, demonstrating the importance that physical OW properties can have for the quality of amended soil.  相似文献   
59.
Feed cost has a significant effect on the economic efficiency of feedlot lambs; therefore, the use of low-cost non-conventional feedstuffs, such as olive pulp (OP), has the potential to decrease the production costs. Because optimum inclusion of OP-treated silages has not been determined in feedlot lambs, an experiment was conducted to determine the effect of inclusion of OP ensiled with additives in the diet on the feedlot performance and carcass attributes of feedlot lambs. Ram lambs of Mehraban and Ghezel breeds (n?=?50 lambs per breed) were randomly allotted to 10 groups and fed with one of the nine diets containing OP silage or a control diet. Silage treatments were: (1) OP silage without additives (OPS), (2) OP ensiled with 8 % beet molasses and 0.4 % formic acid (OP-MF), and (3) OP ensiled with 8 % beet molasses, 0.4 % formic acid and 0.5 % urea (OP-MFU). The control diet contained 50 % alfalfa hay and 50 % barley grain. Three levels from each silage were chosen to replace the barley grain (10, 20, or 30 % dry matter basis). The lambs were slaughtered after 92 days, and the average daily gain (ADG), feed conversion ratio (FCR), and carcass characteristics were determined. Feeding OPS to fat-tailed lambs, at an inclusion level of 30 %, decreased the carcass dressing percentage, mainly as a result of decreased brisket percentage, but the ADG and FCR values were not adversely affected. Ghezel lambs had higher ADG than Mehraban lambs, but the visceral fat weight percentage, flap weight percentage, and back fat depth were higher in Mehraban. The crude protein content in the longissimus dorsi (LD) muscle was higher in Ghezel, but the dry matter percentage was higher in Mehraban (P?<?0.05). Other attributes were not significantly affected by breed (P?>?0.05). Most carcass characteristics, including major cuts, were not affected by OPS feeding; therefore, feeding OPS (up to 30 %) can be economical for feedlot lambs. Most carcass characteristics, including major cuts, were not affected by OPS levels used in this experiment; therefore, inclusion of OPS (up to 30 %) in the diet may reduce the cost of raising feedlot lambs. This also could help alleviate the problem of storage of OP in oil factories.  相似文献   
60.
During spring and summer of 2016, dieback symptoms including blights of leaves, twigs, and acorns were observed on current year shoots of Quercus infectoria in the Zagros oak forests of Iran. The fungus isolated from damaged tissues was identified as Discula quercina based on both morphological characteristics and ITS sequencing. To fulfil the Koch's postulates, a representative isolate was inoculated onto shoots of Q. infectoria and Quercus libani in both laboratory and forest conditions. Responses of the two oak species to inoculation with D. quercina were examined under laboratory and forest conditions in a completely randomized experiment. Discula quercina was clearly involved in oak dieback, and Q. infectoria was more susceptible than Q. libani to damage by the pathogen. This is the first record of the occurrence and pathogenicity of the fungus Discula quercina on Quercus infectoria. The fungus is considered as an emerging pathogen on oak trees in Zagros forests in Iran. Furthermore, the pathogenicity of the Discula quercina on Q. libani under laboratory and forest conditions increases the potential importance of this pathogen in Zagros forests.  相似文献   
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