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31.
Nitrate leaching in a silage maize field under different irrigation and nitrogen fertilizer rates 总被引:4,自引:0,他引:4
Mahdi Gheysari Seyed Majid Mirlatifi Mehdi Homaee Gerrit Hoogenboom 《Agricultural Water Management》2009,96(6):946-954
Quantification of the interactive effects of nitrogen (N) and water on nitrate (NO3) loss provides an important insight for more effective N and water management. The goal of this study was to evaluate the effect of different irrigation and nitrogen fertilizer levels on nitrate-nitrogen (NO3-N) leaching in a silage maize field. The experiment included four irrigation levels (0.7, 0.85, 1.0, and 1.13 of soil moisture depletion, SMD) and three N fertilization levels (0, 142, and 189 kg N ha−1), with three replications. Ceramic suction cups were used to extract soil solution at 30 and 60 cm soil depths for all 36 experimental plots. Soil NO3-N content of 0-30 and 30-60-cm layers were evaluated at planting and harvest maturity. Total N uptake (NU) by the crop was also determined. Maximum NO3-N leaching out of the 60-cm soil layer was 8.43 kg N ha−1, for the 142 kg N ha−1 and over irrigation (1.13 SMD) treatment. The minimum and maximum seasonal average NO3 concentration at the 60 cm depth was 46 and 138 mg l−1, respectively. Based on our findings, it is possible to control NO3 leaching out of the root zone during the growing season with a proper combination of irrigation and fertilizer management. 相似文献
32.
Comparative effects of Shirazi thyme and vitamin E on some growth and plasma biochemical changes in common carp (Cyprinus carpio) during cadmium exposure 下载免费PDF全文
Mohammad Mohiseni Maryam Sepidnameh Dara Bagheri Mahdi Banaee Behzad Nematdust Haghi 《Aquaculture Research》2017,48(9):4811-4821
Phytobiotics include a large number of active components which potentially have a growth‐promoting effects and antioxidant properties. This study was conducted to investigate the protective effects of Shirazi thyme and vitamin E on growth and plasma biochemical parameters of common carp exposed to cadmium. Fish (34 ± 3 g) were divided into four groups and fed four distinct diets including commercial diet without any additive (for control and metal only group) and supplemented with either 1% ground Shirazi thyme or 100 mg kg?1 vitamin E for 45 days. At the end of the feeding trial, all treatments except control group were exposed to sub‐lethal concentration of waterborne cadmium for 15 days and sampling was done on days 0, 7 and 15 after the metal exposure. According to the results, dietary inclusion of thyme prevented the harmful effects of cadmium and also improved fish growth and nutritional indices including weight gain, feed conversion ratio, specific growth rate and condition factor. Results also revealed that Shirazi thyme was more effective than vitamin E. Similarly, no changes in the hepatosomatic, viscerosomatic and bile somatic indices were observed. Plasma enzymes (AST, ALT, ALP and LDH) and metabolites were not altered due to thyme supplementation compared to the control. In conclusion, dietary supplementation of 1% ground Shiraz thyme improved the growth and health status of fish and showed better hepatorenoprotective properties than vitamin E during waterborne cadmium exposure in common carp juveniles. It might be conceivable to consider Shirazi thyme as a potential phytobiotic for incorporation in fish diet. 相似文献
33.
Ali Hosein Yazdi Vajiheh Zarrinpour Elham Moslemi Mohamad Mahdi Forghani Fard 《Iranian Biomedical Journal》2022,26(4):301
Background:Glioblastoma is the most common primary malignant neoplasm of the central nervous system. Despite progress in diagnosis and treatment, glioblastoma still has a poor prognosis. This study aimed to examine whether a signature of three candidate miRNAs (i.e. hsa-let-7c-5p, hsa-miR-206-5p, and hsa-miR-1909-5p) can be used as a diagnostic biomarker for distinguishing glioblastoma from healthy brain tissues. Methods:In this study, 50 FFPE glioblastoma tissue samples and 50 healthy tissue samples adjacent to tumor were included. The expression of each candidate miRNA (i.e. hsa-let-7c-5p, hsa-miR-206-5p, and hsa-miR-1909-5p) was measured using RT-qPCR. To show the roles of each miRNA and their biological effects on glioblastoma development and clinicopathological characteristics, in silico tools were used. ROC curves were performed to assess the diagnostic accuracy of each miRNA. Results:Based on the results, hsa-let-7c-5p and hsa-miR-206-5p were downregulated, while hsa-miR-1909-5p was upregulated in glioblastoma tumors compared to healthy samples. No association was detected between the expression of each candidate miRNA and sex. Except for hsa-let-7c-5p, other miRNAs did not correlate with age status. ROC curve analysis indicated that the signature of candidate miRNAs is a potential biomarker distinguishing between glioblastoma and healthy samples. Only hsa-miR-206-5p suggested the association with poor prognosis in glioblastoma patients. Conclusion:Our findings revealed that the signature of three miRNAs is capable of distinguishing glioblastoma tumor and healthy tissues. These results are beneficial for the clinical management of glioblastoma patients.Key Words: Inflammation, Gastric cancer, Gene expression, Pattern recognition receptors, RNA-seq 相似文献
34.
Kaivan Karimi Asadollah Babai Ahari Mahdi Arzanlou Jahanshir Amini Ilaria Pertot Omar Rota-Stabelli 《European journal of plant pathology / European Foundation for Plant Pathology》2017,147(2):375-387
Anthracnose caused by Colletotrichum spp. is one of main strawberry diseases worldwide. The disease recently arrived in Iran and become epidemic in the Kurdistan province. A combination of morphological, molecular and pathogen-host interaction approaches (referred to the consolidated species concept) were applied to isolates from symptomatic strawberry tissues collected in Iran. Multi-gene phylogenetic analysis based on ITS-rDNA, beta-tubulin (TUB2) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) identified the species as the S5 clade of Colletotrichum nymphaeae. No significant intraspecies variation was observed in terms of morphology and pathogenicity. No significant genetic variation was observed among the isolates using inter simple sequence repeat analysis (ISSR) and primer pair combination of ERIC1/BOX and ERIC2/BOX fingerprinting markers. Based on the results of this study, it can be postulated that the C. nymphaeae population in Iran established itself from a single origin due to a founder effect. More generally, molecular dating based on relaxed clocks indicates co-radiation of C. nymphaeae S5 and strawberry plants and suggests high reciprocal specificity between the host and pathogen. 相似文献
35.
The effects of dietary calcium iodate on productive performance,egg quality and iodine accumulation in eggs of laying hens 下载免费PDF全文
R. Bakhshalinejad A. Hassanabadi H. Nassiri‐Moghaddam H. Zarghi 《Journal of animal physiology and animal nutrition》2018,102(3):746-754
The aim of this study was to examine the effects of various levels of supplemental calcium iodate (CI) on productive performance, egg quality, blood indices and iodine (I) accumulation in the eggs in commercial laying hens. A total of 240 White Leghorn layers (Hy‐line W36) were divided through a completely randomized design into six treatments with five replicates and eight hens per each at 32 weeks of age. This experiment lasted for 12 weeks. Concentrations of I in the mash diets were 0.74, 3.13, 5.57, 8.11, 10.65 and 12.94 mg I/kg of feed in treatments 1–6 respectively. The added doses of CI were included 0.0 (control), 2.5, 5.0, 7.5, 10.0 and 12.5 mg/kg of diet for treatments 1–6 respectively. There were no significant differences in productive performance among the treatments. The highest eggshell strength was observed in group fed diet containing 3.13 mg I/kg (p = .014). The highest percentage of calcium and lowest percentage of phosphorus in eggshell were observed in group fed diet containing 12.94 mg I/kg (p = .0001). Feeding hens with diet containing 12.94 mg I/kg increased serum triiodothyronine‐to‐thyroxine ratio (p = .0001). Serum alanine aminotransferase activity in hens fed diet containing 12.94 mg I/kg was significantly more than control (p = .041). Blood Serum triglycerides in hens fed diet containing 8.11 mg I/kg were significantly higher than control (p = .0001). Edible fraction of the eggs of birds fed diet containing 12.94 mg I/kg was enriched by I almost 3 times more than those fed diet containing 0.74 mg I/kg. The results suggested that egg production, egg mass, feed intake and feed conversion ratio were not significantly affected by dietary I levels. Iodine accumulation in the eggs were increased by increasing dietary I levels and the level of 10 mg/kg CI could supply I enrichment of the eggs. 相似文献
36.
The article shows results of an international and interdisciplinary project with the title ‘Rainfall and its Erosivity in Ethiopia’. The article contains information about the traditional soil conservation practices, the reasons for intervention with traditional soil conservation technologies, the historical background of instutionalized soil conservation activities, the institutional frame work for soil conservation activities and their achievements, and the different departments and organisations for soil and water conservation as far as soil erosion in Ethiopia is concerned. As a conclusion and recommendation, the major constraints of the past activities and the current situation including future trends were discussed. 相似文献
37.
Marjan Zargar Seyed Hadi Razavi Seyed Mahdi Ojagh 《Journal Of Aquatic Food Product Technology》2013,22(8):1311-1322
ABSTRACTIn the present study, aqueous solutions of sodium caseinate (SC) 8% (w/w) were provided in the form of four treatments—including SC without any essential oil (EO) as well as SC with 0.25, 0.5, and 1% (v/w) concentrations of Zataria moltiflora EO. Fish samples were treated with aqueous solutions and stored at 4 ± 1°C for 20 days. The control and treated fish samples were analyzed for chemical (total volatile basic nitrogen, pH, thiobarbituric acid, peroxide value), microbiological (total viable count and psychrotrophic count), and sensory analyses every 4 days. Based on results, SC edible coating had no antimicrobial effect but acted like a barrier against the fish flesh contamination. Moreover, incorporating Zataria moltiflora EO with SC edible coating reduces peroxide value and thiobarbituric acid-reactive substances values as well as the chemical and microbiological spoilage of refrigerated ?sh samples. Furthermore, sensory evaluation results showed that the presence of thyme oil improved the sensory quality of the rainbow trout. 相似文献
38.
BACKGROUND: Viral protein-1 (VP1) is a major capsid protein of Coxsakievirus B3 (CVB3) that plays an important role in directing viruses towards permissive cells and acts as a main antigenic site of the virus in eliciting of host immune response, hence it seems VP1 can be considered as a vaccine candidate against CVB3 infection. In this study, cDNA of VP1 was prepared, cloned into pET expression vector and the recombinant protein (VP1) was over expressed in E. coli. METHODS: The viruses were grown in suspension cultures of Vero cells with an input virus multiplicity of 10-50 plaque-forming units/cell. After observing complete cytopathic effect, the total RNA (cells and virus) was prepared for RT-PCR and by using specific primers, VP1 cDNA was amplified and ligated into pET vectors (32 a and 28 a). The recombinant vector was transferred into competent E. coli (BL-21) and after selection of proper colony, which carried correct cDNA within the vector; cells were cultured and induced with isopropyl B-D-thiogalactopyranoside, in order to express protein (VP1). The cultures were tested for presence of VP1 by SDS-PAGE and Western-Blotting analysis. RESULTS: Molecular techniques such as PCR which showed exact defined size of the VP1 (819 bp), restriction digestion and finally immunoblot analysis of over expressed protein; all confirmed the correct cloning and expression of VP1 in this research. CONCLUSION: In this research, full length of VP1 as major capsid protein of CVB3 was over expressed in E. coli which, can be used for further studies, including neutralizing antibody production against CVB3. 相似文献
39.
Persistence of white clover (Trifolium repens) in mixtures was studied in a long-term experiment. Mixtures of two cultivars of perennial ryegrass (Lolium perenne) with contrasting growth habits and three white clover cultivars differing in leaf size were sown in 1991 and evaluated at two cutting frequencies. During 1995 and 1996 mixtures with large-leaved white clover cv. Alice had the highest dry-matter (DM) content, clover and N yield, and the highest white clover content, and mixtures with medium-leaved Retor the lowest, whereas mixtures with small-leaved Gwenda yielded most grass DM. In 1995 averaged over cutting treatments and mixtures, the mixtures yielded 11·8 t DM ha?1 with a white clover content of 0·6; the apparent N fixation was 393 kg N ha?1. In 1996 these values declined to 8·5 t DM ha?1, 0·48 white clover and 236 kg N ha?1. There was no significant effect of cutting frequency on DM yield or white clover content, whereas the effects of grass cultivar were not consistent. In spring there was a peak in the DM production of the mixtures, coinciding with a peak in production of the grass component. However, in summer and autumn the seasonal pattern of DM production of the mixtures was similar to that of the white clover component. Both cultivars of perennial ryegrass showed the same seasonal response, but the seasonal growth pattern of white clover differed slightly between clover cultivars and cutting treatments. In later years only one cutting frequency was imposed, and no yield measurements were taken. White clover was judged to have performed well during 1997; the clover content in September was very high (0·76), whereas in October 1998 it was 0·45. Mixtures with Alice contained most white clover. Despite fluctuations in white clover content during 1991–98, all clover cultivars had persisted 7 years after sowing, irrespective of companion grass cultivar, at both cutting treatments. 相似文献
40.
Kalanaki Mahdi Ritzema Henk Bamshad Roghayeh Jones Edward Fazilatnia Mojtaba 《Paddy and Water Environment》2020,18(2):469-479
Paddy and Water Environment - Application of common leaching and flushing methods is often impractical due to freshwater scarcity, groundwater pollution and a lack of suitable drainage systems. To... 相似文献