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91.
Soil–plant water dynamics is a major driving factor on crop yield which could be improved under optimal irrigation strategy. The soil water dynamics under partial root-zone drying (PRD) and its consequent effects on maize economics returns were investigated in a two-year field study in the research field of Sari Agricultural Sciences and Natural Resources University. Irrigation treatments included full irrigation (FI) and two PRD treatments including PRD1 and PRD2, receiving 100%, 75% and 55% of crop water demand at each irrigation event, respectively. TDRs were used for measuring soil water contents on a daily basis. Economic analysis was done based on net present value (NPV), benefit-to-cost ratio (B/C) and internal rate of return (INRR) indices. Applying PRD1 treatment increased soil wetting front advance by 110–330% compared those for other treatments which caused 50% increase in root water uptake. Improved soil water dynamics under PRD1 prevented a significant reduction in maize grain yield, leading to 37.7%, 6.14% and 192% increase in NPV, B/C and INRR, respectively, under PRD1 than those for FI treatment. Thus, PRD1 was the most economic water-saving irrigation strategy under which 25% of irrigation water would be saved due to a better utilization of soil water supply.  相似文献   
92.
In order to investigate the effects of nitrogenous fertilizers (biological, chemical, integrative) on quantity and quality of forage-medicine in the additive intercropping of sorghum with fenugreek, an experiment was performed in two agronomic years 2010–2011 and 2011–2012 in the Research Farm of Agricultural Faculty of Tehran University located in Dolatabad, Karaj, as split-plot in the form of randomized complete block design (RCBD) with three replications. The main treatments consisted of the control or without fertilizer (N0), biofertilizer (Nbi) (Azotobacter, Rhizobium, Azospirillum, mycorrhiza), chemical nitrogen fertilizer (Nch 100) and integrative fertilizer including biofertilizer plus 50% chemical nitrogen fertilizer (Nbi + Nch50). The subtreatments included sole cultivation of fenugreek without weeds (T0), sole cultivation of fenugreek with weeds (Tw), sole cultivation of sorghum without weeds (S0), sole cultivation of sorghum with weeds (Sw), cultivation of sorghum + 50% fenugreek (ST50) and cultivation of sorghum + 100% fenugreek (ST100). Based on the results, the highest effective extract of fenugreek (trigonelline) and fenugreek dry matter was gained through the application of biological fertilizer + the sole fenugreek treatment (no weeds). Moreover, the highest sorghum dry mater was yielded by the use of the integrative fertilizer + the sole sorghum (no weeds) treatment; however, the highest total dry matter was observed to be more in the mixed treatment of integrative fertilizer and sorghum + 50% fenugreek. The lowest weed biomass was also linked to the integrative treatment biological fertilizer and sorghum + 100% fenugreek.  相似文献   
93.
A wide variety of clinical and paraclinical methods have been used for diagnosis of equine grass sickness (EGS), but none of them could absolutely confirm the diagnosis, and postmortem pathologic examination is still considered the final step in precise diagnosis of EGS. Use of in vitro cell toxicity caused by EGS serum on neuronal cell lines was investigated. Three well-known cytotoxic methods were used to investigate the cytotoxicity of EGS serum on neuro-2a and genetically engineered PC12 Tet-Off P53 cells. The results of alamar blue reduction as an index for mitochondrial activities and intracellular adenosine triphosphate content assays, but not neutral red uptake, indicate that the EGS serum may affect the mitochondrial function and cellular metabolism at up to 60% of the cases. The results of present study might be used for diagnosis of EGS cases. Further studies with high sample size may lead us to uncover the pathogenesis of EGS and to increase the sensitivity and applicability of in vitro techniques as diagnostic tools.  相似文献   
94.
In this study, viral pathogens associated with nine outbreaks of naturally occurring dairy calf pneumonia in Mashhad area of Khorasan Razavi province from September 2008 to May 2009 were assessed. Five diseased calves from each farm were chosen for examination. Acute and convalescent serum samples were taken from calves with signs of respiratory disease. Sera were analyzed for antibodies to bovine viral diarrhea virus (BVDV), bovine herpesvirus type 1 (BHV-1), bovine respiratory syncytial virus (BRSV), parainfluenza virus type 3 (PI-3V), and bovine adenovirus-3 (BAV-3) by indirect ELISA kits. Among 42 serum samples collected at sample 1, seroprevalence values for viruses BHV-1, BVDV, BRSV, PI-3V, and BAV-3 were 61.9% (26), 57.1% (24), 64.2% (27), 90% (38), and 61.9% (26), respectively. Seroconversion to BVDV, BRSV, PI-3V, and BAV-3 occurred in 11.9% (5), 16.6% (7), 26.1% (11), and 21.4% (9) of animals, and 52.3% (22) had generated antibodies against one or more viral infections at sample 2. In addition, no significant relationship between seroprevalence of BHV-1, BVDV, BRSV, PI-3V, and BAV-3 and dairy herd size was observed (P > 0.05). According to serological findings, BHV-1, BVDV, BRSV, PI-3V, and BAV-3 are common pathogens of the dairy calf pneumonia in dairy herds in Mashhad area of Khorasan Razavi province, Iran.  相似文献   
95.
Immune deficiency and altered immunity are among the best characterized and strongest known risk factors of non-Hodgkin lymphomas (NHL). For instance, chronic inflammation or certain disturbances in the immune system are associated with an increased lymphoma risk. Occupational and environmental factors (i.e., dioxin) as well as lifestyle factors (i.e., obesity) may contribute to these risk factors. The precise role of these factors in the etiology of NHL, however, is still not entirely clear. Although the existing epidemiologic studies have not revealed consistent patterns of perturbations of the immune system by these factors, the findings might suggest an adverse impact on both the humoral and cell-mediated immune system.  相似文献   
96.
Information on different rangeland plants' nutritive values on different plant parts and for various habitats is important in rangelands management. Effects of different plant parts (stems and leaves) of the Jasminum fruticans L. plant species on forage quality indicators were investigated in two regions in 2015. Plant samples were collected from Sharlogh rangelands and cultivated in the Research and Education Center of Agricultural and Natural Resources (RECANR) in Iran with completely randomized design with three replications in each plant sample. The plant leaves and stems samples were oven-dried at 80°C for 24 hr, and then analyzed for crude protein (CP), crude fiber (CF), dry matter (DM), ether extract (EE), crude ash (CA), metabolizable energy (ME), and mineral elements, including calcium (Ca) and phosphorus (P). Results showed that the forage quality indicators in different regions were statistically significant, except for the CA. Also, nutritive values differed significantly (p < 0.01) between different plant parts, except ME parameter. Results also indicated that J. fruticans due to its high tissue CP content is a valuable source of forage for livestock.  相似文献   
97.
Nylon 6 fabric with self-cleaning properties was prepared by corona discharge pre-treatment and coating with TiO2 nanoparticles (NPs) using pad-dry-cure technique. The self-cleaning property was studied by discoloration of methylene blue (MB), ketchup, tea and coffee stains from the corona+TiO2 treated nylon-6 fabric. Color difference (ΔΕ*), reflectance (R) and K/S of MB stain were investigated by diffuse reflectance spectrophotometry. The MB stain was almost completely removed from the corona+TiO2 treated nylon surface after 24 h under UV light/daylight irradiation. Both of these phenomena (corona and TiO2) led to an increase in the discoloration of stains under UV and daylight irradiations. The EDS analysis showed an increase in the concentration of deposited TiO2 NPs coating after corona treatment. The FE-SEM images revealed that the surface of nylon 6 was coarser after the corona treatment. Also, the FE-SEM micrographs exhibited that a uniform layer of TiO2 NPs was formed on the corona treated nylon fabric. The corona+TiO2 treated nylon illustrated antibacterial activity against E. coli and B. subtillis microorganisms. The EDS and FE-SEM analysis confirmed that after 5 washing cycles, the amount of TiO2 NPs was higher on the surface of corona+TiO2 treated nylon than that of the fabric only treated with TiO2 without corona pretreatment. This result justifies that the corona+TiO2 treated nylon fabric with appropriate self-cleaning property can be applied cost-effectively in the textile industry.  相似文献   
98.
Journal of Plant Diseases and Protection - South American Tomato Pinworm (SATP), Tuta absoluta Meyrick (Lepidoptera: Gelechiidae), is one of the most devastating pests in tomato greenhouses....  相似文献   
99.
The long-term performance and benefits of charcoal application on the carbon sequestration and properties of forest soils in temperate or non-tropical regions has not been studied in detail in spite of its important role in global warming. This study was conducted to describe the long-term charcoal-induced changes in organic carbon (OC) content and other soil properties of temperate deciduous forests in Mazandaran province, northern Iran. Three sites were sampled to collect composite soil samples from two depths (0–20 and 20–40 cm) inside and outside of a plot of charcoal-enriched soils surrounding a historical charcoal production site (abandoned for more than 120 years). The presence of charcoal in soils for about 120 years elevated significantly the black carbon, total OC, natural soil OC, total nitrogen, dissolved organic matter, soil OC density, exchangeable bases, saturated hydraulic conductivity, available water capacity and available Fe, Mn and Zn compared to the adjacent reference soils. Cation exchange capacity (CEC) and pH were 15.5 cmolc kg^-1 and 0.5 units, respectively, higher than the adjacent reference soils at 0–20 cm soil depth. However, electrical conductivity (EC), bulk density and available Cu were higher in the adjacent reference soil. The aged charcoal had no significant effect on the microbial respiration rate of studied soils. The results of this study provide new insights and strong support for the long-term benefits of biochar application as a management strategy for improving soil productivity as well as sequestering large quantities of durable carbon in soils of the region and mitigating global warming.  相似文献   
100.
The objective of this experiment was to assess the effects of organic or chemical nutrient solutions on the growth and composition of lettuce (Lactuca sativa L.) in greenhouse production. Hoagland and Arnon nutrient solution, an organic hydroponics solution, and no fertilization were factored with lettuce cultivars of different phenotypes, iceberg, romaine, loose head, and loose leaf. Lettuce growth was higher with Hoagland and Arnon solution than with the organic fertilizer or with no fertilization. The organic fertilizer increased growth above no fertilizer applied. Hoagland and Arnon solution gave the highest concentration of nitrogen, potassium, magnesium, and iron in the lettuce whereas lettuce grown with the organic fertilizer had the highest phosphorus. Plant nutrient accumulation differed slightly among the cultivars. Hoagland and Arnon solution produced high nitrate in leaves. Nitrate concentrations with organic or no fertilization were low. Loose head or loose leaf cultivars had higher nitrate than romaine or iceberg.  相似文献   
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