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141.
Conservational tillage (CT) in combination with broad spectrum herbicide may be more efficient and economical in controlling weeds,reducing cost of cultivation,and enhancing wheat yield.Field experimen...  相似文献   
142.
Soil factors such as pH, calcium, carbonate, and bicarbonate precipitation products in calcareous soils reduce iron (Fe) availability to crops and limit grain Fe concentrations. In the present greenhouse study, we evaluated the potential of Fe fertilizer amendments combined with organic amendments, like biochar (BC) and poultry manure, in sulfur (S)-treated low pH calcareous soils (pHS1) to assess Fe biofortification of maize. Elemental sulfur (S) was used both for lowering soil pH and Fe solubilization. Soil pH was successfully lowered down from 7.8 to 6.5 by S application at the rate of 2.5 g kg?1 soil. Pot experiment results revealed that Fe fertilizer combined with BC and S (pHS1) significantly increased root and shoot dry weight, grain weight, photosynthetic rate, transpiration rate, and stomatal conductance by 69%, 86%, 28%, 74%, 57%, and 33%, respectively, relative to the control. Similarly, combined application of Fe + BC in S-amended (pHS1) soil increased starch (34%), protein (64%), and fat (1 fold) while antinutrient phytate and polyphenols were decreased up to 29% and 40%, respectively, over control. Regarding the maize nutrients profiles, application of Fe with BC gave the maximum increase of Fe and ferritin was increased 1.7 fold at pHS1. The results of this study showed that Fe fertilization with BC at pHS1 soil is beneficial for crop growth and Fe bioavailability.  相似文献   
143.
The objective of this work was to study the effect of different biochar on alkaline calcareous soil, inherently low in soil organic carbon and fertility. Experiments were conducted in laboratory and greenhouse. Biochar was produced from wheat and rice straws at pyrolysis temperatures of 300°C, 400°C and 500°C (denoted as WSB300, WSB400, WSB500, RSB300, RSB400 and RSB500, respectively). In the first experiment, soil was incubated with biochar (1.0 % w/w) for up to 50 weeks. The results indicate that, WSB300 caused a significant decrease in soil pH and increased the CEC and nutrients (N, P and K) after 50 weeks of incubation. In the second experiment, maize plants were grown in pots containing calcareous soil amended with WSB and RSB for 60 days the results revealed that the application of WSB300 caused a significant increase in shoot (36%) and root (38%) dry matters over the respective control. Moreover, the highest nutrient concentrations (N and P) in shoot and root were observed with the WSB300 compared to other treatments. Therefore, it is concluded that application of wheat straw biochar produced at low temperature (WSB300) could be successfully used to improve soil properties and growth of plants in calcareous soils.  相似文献   
144.
The reduction in atmospheric inputs of SO 4 2- as a result of stricter regulations of sulfur emission and the depletion in sulfur reserves following the intensification of agricultural production has caused a serious decrease in soil S-concentration. This would markedly affect growth and quality of numerous economically important plants. Foeniculum vulgare or fennel is one of the most cultivated aromatic and medicinal plants, mostly used for their powerful therapeutic effects. Being one of the cultivated species, Foeniculum vulgare could be affected by environmental disturbances like sulfur deficiency. In this work, the poor sulfur supply had a serious impact on the therapeutic quality of fennel seed extracts. At the application of sulfur deficiency, total phenolic compounds of fennel seeds extract decreased by 30% and their total antioxidant activity decreased by 21%. Sulfur starvation also reduced the antibacterial activity of fennel seeds against Staphylococcus aureus, Enterococcus faecalis, and Pseudomonas aeruginosa by increasing the MIC of seed extracts.  相似文献   
145.
Citrus family especially Grapefruit, has attained considerable attention due to the presence of a number of essential components that have cardiovascular and anti-hypertensive properties. The juice and essential oil extracted from eight recently released grapefruit cultivars were used to study physicochemical and antioxidant properties. The total soluble solids (TSS), titratable acidity (TA) and pH of juice samples extracted from various grapefruit varieties differed significantly. The refractive index, specific gravity and optical rotation values for the oil varied from 1.473 to 1.396, 0.863 to 0.847 and +93 to +86, respectively. The percent 2,2-diphenyl-1-picrylhydrazyl radical activity (% DPPH activity) and ferric reducing antioxidant power (FRAP) values for grapefruit juice and peel oil varied from 24.06 to 18.79, 2.91 to 1.44 mmol g–1 and 84.87 to 74.73, 7.76 to 5.73 mmol g–1, respectively. There were significant differences in physicochemical, antioxidant properties and volatile profiles of extracted juice and oil. The oil exhibited higher DPPH and FRAP values than the juice. Among different components identified which accounted for over 99% of the volatile fraction, limonene, myrcene, and benzopyran were major components in all oil samples.  相似文献   
146.
Flavonoids are widely-distributed polyphenolic secondary metabolites with diverse biological activities in plants and benefit human health as protective dietary agents. They participate in plants' responses to harsh environmental conditions and effectively regulate the cell differentiation and growth. In plants, the majority of their functions are attributed to their strong antioxidative properties. Similarly, dietary flavonoids protect the human body against free radicals which are associated with the development of cancer and atherosclerosis. Plants rich in polyphenols have been used to cure various diseases because of their antibacterial, antiviral, antifungal and anticancer properties. This review summarizes the up-to-date research trends and development on flavonoids and its derivatives, working mechanisms and potential functions and applications particularly in relation to plant protection and human health. Towards the end, notable concluding remarks with a close-up look at the future research directions have also been presented briefly.  相似文献   
147.
We have previously described the development of a one-tube SYBR Green real-time RT-PCR assay for the detection and quantitation of infectious salmon anemia virus (ISAV) in various biological samples. The twofold aim of the present study was to verify that the optimized SYBR Green real-time RT-PCR conditions could detect ISAV isolates of different geographic origins, and to analyze the growth patterns of the selected ISAV isolates in the Chinook head salmon embryo (CHSE)-214 cells by this assay to better characterize their CHSE-phenotypes. A total of 24 ISAV isolates were used in this study. The results indicated that the SYBR Green real-time RT-PCR could detect ISAV of different geographic origins or laboratory sources. The capacity of ISAV isolates to cause cytopathic effects (CPE) in the CHSE-214 cell line, viral titration of the infected CHSE-cell harvests, and analysis of viral RNA levels in CHSE-214 cells at post-infection day zero, 7 and 14 by SYBR Green real-time RT-PCR confirmed the existence of three CHSE-phenotypes of ISAV: replicating cytopathic, replicating non-cytopathic, and non-replicating non-cytopathic. The identification of these three CHSE-phenotypes of ISAV has important implications from diagnostic and biological points of view.  相似文献   
148.
The plants of two onion cultivars Sturon and Stuttgarter were raised from sets and placed in a growth room at 12 °C, a light flux density of 120 μmol m−2 s−1 and a 16 h photoperiod. Cultivar Stuttgarter took 195 days to initiate, whereas time for initiation in cv. Sturon was 201 days. After initiation the plants were transferred to wide range of photo-thermal regimes consisting of six set point temperatures (6, 10, 14, 18, 22 and 26 °C) and four photoperiods (8, 11, 14 and 17 h day−1). An overall mean temperature for all developmental stages under each photo thermal combination was 12.2, 12.4, 15.9, 17.8, 23 and 24.4 °C. Time to inflorescence appearance, spathe opening and floret opening decreased linearly as temperature and photoperiod increased. At low to mild temperatures (12.2–17.8 °C), longer photoperiod enhanced florets per umbel, whereas at higher temperatures (23–24.4 °C), the floret number declined with lengthening photoperiods. As the photoperiod extension in each temperature advanced inflorescence appearance, spathe opening and floret opening and this would be beneficial in a programme to accelerate seed production in onion.  相似文献   
149.
Janbaz KH  Saeed SA  Gilani AH 《Fitoterapia》2002,73(7-8):557-563
Rutin, a well-known flavonoid was investigated for its possible protective effect against paracetamol- and CCl(4)-induced hepatic damage. Paracetamol produced 100% mortality at the dose of 1 g/kg in mice while pre-treatment of animals with rutin (20 mg/kg) reduced the death rate to 40%. Oral administration of a sub-lethal dose of paracetamol (640 mg/kg) produced liver damage in rats as manifested by the rise in serum level of transaminases (AST and ALT). Pre-treatment of rats with rutin (20 mg/kg) prevented the paracetamol-induced rise in serum enzymes. The hepatotoxic dose of CCl(4) (1.5 ml/kg; orally) also raised the serum AST and ALT levels. The same dose of rutin (20 mg/kg) was able to prevent the CCl(4)-induced rise in serum enzymes. Rutin also prevented the CCl(4)-induced prolongation in pentobarbital sleeping time confirming its hepatoprotectivity. These results indicate that rutin possesses hepatoprotective activity and the presence of this compound in Artemisia scoparia may explain the folkloric use of the plant in liver damage.  相似文献   
150.
The validity of an ovine growth hormone (OGH) assay for the detection of feline growth hormone (FGH) was demonstrated by the parallel displacement of radiolabelled OGH by standard concentrations of OGH and serial dilutions of pooled FGH-rich serum. The minimum detectable limit of the assay was 1.67 microg/l. The mean (sd) basal fasting FGH level in 19 non-acromegalic, non-diabetic cats aged two to 16 years was 4.01 (1.38) microg/l (range 1.87 to 6.33); 19 acromegalic cats had significantly higher FGH levels (range 8.45 to 33.2 microg/l). There were no significant differences in the FGH levels measured when aprotinin was added to the samples or when plain serum and serum gel separation tubes were used for blood collection, but the FGH levels were significantly higher when the samples were collected into EDTA. There were also no significant differences between the concentrations of FGH measured in samples in which the separation of the serum and storage had been delayed by 24 hours, or in samples that had been stored for up to four weeks at -20 degrees C.  相似文献   
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