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11.
Parisa Maleki Saeed Saadat Forood Sharifi Farhad Dehghany Masomeh Salehi 《Communications in Soil Science and Plant Analysis》2018,49(15):1815-1825
Salinity is one of the major agricultural problems in arid and ?semi-arid regions. Considering the variation of plant’s ?sensitivity to salinity during growth, a greenhouse study with completely randomized design? was conducted to determine the relative salinity tolerance of Quinoa (Chenopodium quinoa Willd.) at different growth stages from seedling establishment to maturity (establishment, flowering and seed filling) by evaluating the Salinity Threshold Value (STV). Eight levels of ECi (i.e., Non-saline, 2, 4, 8, 12, 15, 20, 25 dSm?1) with four replications and five levels (i.e., Non-saline, 10, 15, 20, 25 dSm?1) with three triplications were applied at first and two last growth stages, respectively. A ?comparison was performed on some growth and yield parameters of plants irrigated by considering STV (T) and ?plants irrigated permanently by mentioned salinity levels regardless of STV (P) to choose ?which method (P or T) is better at each salinity level. The STV was ?evaluated 8, 20 and 15 dSm?1 at each growth stage, respectively. Seedling of Quinoa was more sensitive to salinity than the mature plant. Therefore, after establishment Quinoa has the ?feasibility of irrigation by high-saline waters. The (P) ?method was suitable only if the freshwater was available during all growth period of the plant; otherwise at higher salinities irrigation should be performed by considering STV (T method) to minimize the intensity of growth and yield reduction and to prevent yield loss at very high salinities. To achieve this, if high-saline water is available it’s possible to ?use plant propagation techniques or cultivating Quinoa simultaneously with seasonal rainfall.? 相似文献
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Sahar Hatami Saeed Zavareh Mojdeh Salehnia Taghi Lashkarbolouki Mohammad Taghi Ghorbanian Isaac Karimi 《Iranian Biomedical Journal》2014,18(3):181-188
Background: Cryopreservation of pre-antral follicles is a hopeful technique to preserve female fertility. The aim of the present study was to evaluate reactive oxygen species (ROS) and total antioxidant capacity (TAC) levels of mouse vitrified pre-antral follicles in the presence of alpha lipoic acid (ALA). Methods: Isolated pre-antral follicles (140–150 µm in diameter) were divided into vitrified–warmed and fresh groups. Each group was subjected to in vitro maturation with or without ALA for 12 days, followed by adding human chronic gonadotropin to induce ovulation. In vitro fertilization was performed to evaluate their developmental competence. In parallel, the amount of ROS and TAC were assessed after 0, 24, 48, 72, and 96 h of culture by 2'',7''-dichlorofluorescin assay and ferric reducing/antioxidant power assay, respectively. Results: The respective rates of survival, antrum formation, and metaphase II oocytes were significantly higher in ALA-supplemented groups compared to the groups not treated with ALA. TAC and ROS levels were significantly decreased and increased, respectively during the culture period up to 96 h in the absence of ALA in both vitrified and non-vitrified samples. However, with pretreatment of ALA, TAC levels were increased significantly and remained constant up to 96 h in vitrified-warmed pre-antral follicles, while ROS levels completely returned to the level of starting point after 96 h of culture in the presence of ALA. Conclusion: Pretreatment of ALA positively influences development of pre-antral follicles in vitrified and non-vitrified samples through increasing follicular TAC level and decreasing ROS levels. Key Words: Vitrification, Pre-antral follicle, Alpha lipoic acid (ALA), Reactive oxygen species (ROS), Total antioxidant capacity (TAC) 相似文献
13.
Mohsen Bagheri Bodaghabadi M.H. Salehi José A. Martínez-Casasnovas J. Mohammadi N. Toomanian I. Esfandiarpoor Borujeni 《CATENA》2011
Topography has an important influence on the distribution of soils and their properties, especially in hilly lands, and related data are easily available, measurable and recognizable from digital elevation models (DEMs). To our knowledge, little attention has previously been paid to the effect of DEM attributes on the distribution of soils, using ordination methods. The objective of this study was to analyze relationships between topographical properties derived from DEM and soil distribution and to discuss their applicability in Digital Soil Mapping (DSM). The study was carried out in the Borujen area of central Zagros, Iran. A total of 13 plots (each one of 6.75 ha) were set up to calculate the percentages of the dominant soil series. Fifteen DEM attributes, including slope, aspect, curvature, maximum and minimum curvature, planform curvature, profile curvature, tangent curvature, wetness index, power index, sediment index, area solar radiation, direct radiation, diffuse radiation and direct duration were also computed. Canonical Correspondence Analysis (CCA) was used to summarize the data set and to evaluate the expected relationships. The results obtained show that there was a relatively strong correspondence between soils' series distribution and topographical properties. The DEM attributes that best related to the first axis were maximum curvature, slope and sediment index, all of which significantly positive correlated, and wetness index, direct duration and minimum curvature, all of which were negatively related. The second axis showed a negative trend with wetness index, direct duration and aspect, and a positive trend with sediment index and slope. These gradients were closely related to the first three canonical axes and explained 71.8% of the total variance of the soil series. The residual variance (28.2% of the total variance) was related to other soil forming factors, like parent material and vegetation cover, which were not investigated in this study. Considering that DEMs are still the most important source of environmental information, understanding the role of topographical factors in a region should help us to identify soils and their properties better and enable us to apply these derivates as input data in DSM. 相似文献
14.
Mohammad Jafar Bahrani Foroud Salehi Sayed Abdolreza Kazemeini 《Archives of Agronomy and Soil Science》2013,59(2):179-187
Crop residues are beneficial substances affecting crop production and soil properties. A field experiment was carried out to evaluate the effects of wheat (Triticum aestivum L.) residue rates (0, 25, 50 and 75%) combined with N levels (0, 34.5, 69, 103.5 kg ha?1) on yield and yield components of two red common bean (Phaseolus vulgaris L.) cultivars and to monitor chemical soil parameters. The experiment was conducted at Research Center, College of Agriculture, Shiraz University, Shiraz, Iran for two years (2008–2009). The experiment was conducted as a split–split plot arranged in a randomized complete blocks design with three replications. The highest seed yield was obtained when 25–50% of residues were incorporated. The highest seed yield, seed weight per plant, 100-seed weight and seed number per pod were obtained with 103.5 kg N ha?1 with no significant difference to 69 kg N ha?1. Residue incorporation significantly increased soil organic carbon (SOC) as well as available K and P content. It is possible to sow red common bean as a double cropping by soil incorporation of 25–50% wheat residues with application of 69 kg N ha?1. 相似文献
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16.
Najati V Ilkhanipour M Salehi S Sadeghi-Hashjin G 《Pakistan journal of biological sciences: PJBS》2008,11(2):250-254
The aim of this study was to investigate the role of Nitric Oxide (NO) in the atresia of ovarian follicles in an animal model. Twenty adult, female rats (90 days old with body weights of210 +/- 10 g in the beginning of the experiments) were divided into 4 groups of 5 each. They were treated twice daily from the subcutaneous route for 21 successive days with either of the following chemicals: nitroglycerine, L-arginine, L-NAME, or saline. On day 22, all animals were sacrificed. Ovaries were dissected out free of connected tissue and were fixed in formaline 10%. Later, paraffine blocks were prepared and serial sections were made by means of H and E routine staining method. Intact and atretic follicles were counted separately. In addition, damages were analyzed qualitatively from the points of view of appearance and morphologic changes. In the evaluation of ovarian follicular structures, different types of healthy as well as atretic follicles were observed. In most of atretic follicles, the oocytes were abnormally elongated and increnation of their outlines were obvious. There were numerous macrophages around and inside of the atretic follicles. Our investigation regarding the distribution of atretic follicles in the ovaries of test groups revealed that atretic follicles in the L-NAME treated group were increased in comparison to the control group. Conversely, however, in the arginine-treated group, the atretic follicles were reduced compared to the control animals. Treatment with nitroglycerine of the rats decreased the number of atretic follicles significantly (p < 0.05) in comparison to the control group. In conclusion, enhanced NO, either from endogenous or exogenous origins, prevents atresia phenomenon, while inhibition of NO exerts an opposite effect. 相似文献
17.
There is general believe that exercise may results in changes that likely reduce the risk of developing cardiovascular disease and may slow the progression of established coronary artery disease. Chronic cardiovascular training results in changes in lipoproteins and apolipoproteins that reflect adaptation to the increased metabolic demands imposed by frequent, vigorous exercise. Moreover, the alterations in lipoproteins vary according to level of physical conditioning and intensity of exercise. One hundred three pre-menopausal physically active women ages 20-50 years old which have been exercising for at least 6 months involve in this study. Upon entering the study subjects were asked to complete questionnaire, regarding personal health and diet history (24 h recall plus 7 days food frequency list). Total calorie intake, level of carbohydrate, protein and fat in the subjects' diet were analyzed. In addition the concentration of women's plasma triglycerides, total cholesterol, LDL-C and HDL-C were also measured and compared with normal value. The results of the present study showed that, the mean total caloric intake of women were 1812.54 kilocalories, where their carbohydrate, protein and fat intake were 67.28, 12.83 and 19.89% of their total calories, respectively. The average age, weight, height and Body Mass Index (BMI) of the women involved in the study were, 30.81+/-8.87 years, 57.85+/-7.79 kg, 160.32+/-5.36 cm and 22.53+/-2.82 kg m(-2), respectively. Plasma lipid and lipoprotein concentration of women were also in normal range with the lowest in those who exercise for more than one year and physical education teacher. 相似文献
18.
Naghizadeh B Boroushaki MT Vahdati Mashhadian N Mansouri MT 《Iranian Biomedical Journal》2008,12(2):93-100
Background. The major side effect of cisplatin, used in some tumours, is nephrotoxicity. Reactive oxygen species and oxidative damage are the most important factors in cisplatin-induced acute renal failure. The main purpose of this study is to investigate the protective effects of crocin against cisplatin-induced acute renal failure and oxidative stress in rat. Methods. In this study, animals were randomly divided into 5 groups (6 each). Group one received normal saline (2 ml/day, i.p.). Group two received a single dose of cisplatin (5 mg/kg, i.p.). Groups 3 to 5 received crocin (100, 200 and 400 mg/kg, i.p., respectively, for 4 consecutive days one hour before a single dose of cisplatin (5 mg/kg) only at the first day. Blood samples were taken out (on the fifth day) for measuring the level of urea and creatinine. The kidneys were removed for histopathological and biochemical examinations. Furthermore, 24-hour urinary factors were measured. Results. Blood urea, creatinine and urinary glucose and protein concentrations in crocin-treated groups were significantly lower than those of cisplatin-treated group in a dose-dependent manner. Histopathological studies showed a massive damage in S3 segment of proximal tubules in cisplatin-treated group. No damage was observed in crocin-treated groups. Crocin treatment resulted in a significant and dose-dependent reduction in malondialdehyde concentration as compared to the cisplatin-treated group. Moreover, crocin produced a significant elevation in total thiol and glutathione peroxidase concentrations, as compared with cisplatin-treated group. Conclusion. The results of the present study suggest that crocin has a protective effect against cisplatin-induced acute renal failure and relative oxidative stress. 相似文献
19.
Turfgrasses are commonly propagated by seeds. In some genera of turfgrasses, the presence of low germination percentage (GP) or rate is the main problem in seed propagation. The present investigation was undertaken to determine the best concentration and duration of sulphuric acid treatment for seeds of the following turfgrass genera: Cynodon dactylon [L.] Pers.; Festuca rubra L. var. rubra‘Shadow’; Lolium perenne L. ‘Barball’ and Poa pratensis L. ‘Merion’. In the first experiment, sulphuric acid was used with concentrations of 0 (control), 25, 50, 75 and 100 % for 10, 15, 20, 25 and 30 min. In the second experiment, effects of light/dark (16/8) or dark conditions on germination rates of different mentioned genera were investigated using the best specific acid treatments. Each treatment was replicated four times with 100 seeds per replicate kept in plastic Petri dishes. The results indicated that in Cynodon, using 50 % acid for 20–25 min had highest GP and mean daily germination (MDG) in light/dark; in Festuca, using 25 % acid for 15 min had highest GP and MDG in light/dark; in Lolium using 50 % acid for 10 min had highest MDG in dark and in Poa, using 50 % acid for 15–25 min had highest MDG in dark. Both Cynodon and Poa had the highest and Festuca had the lowest GPs. Cynodon and Festuca had the highest and lowest MDGs, respectively. This simple procedure, with considerable results, may be replaced to time-consuming and expensive methods such as seed priming. 相似文献
20.
The essential oil of Oliveria decumbens was investigated for its components and antimicrobial activity against six bacteria and two fungal strains. The essential oil was characterized by a high amount of oxygenated monoterpene components of which thymol (47.06%) and carvacrol (23.31%) were the major components. The oil exhibited high antimicrobial activity against all tested Gram+ and Gram- bacteria and fungal strains. 相似文献