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51.
Acer velutinum Boiss is a valuable tree species native to Iran, and its seeds possess physiological dormancy that hampers seedling production in the nursery for large-scale reforestation efforts. The aim of this study was to determine the optimal dormancy breaking treatments for A. velutinum seeds. We conducted a factorial experiment involving six seed lots collected along an elevation gradient from 300 to 1800 m at 300 m interval and four cold-moist stratification periods (0, 4, 8 and 16 weeks) at 4℃ and 70% relative humidity. The result shows that the germination of cold-moist stratified seeds was significantly (p < 0.0001) higher than the control for all seed lots. The highest germination capacity was recorded after 16 weeks of cold-moist stratification for all seed lots (68% 88% depending on the seed lot) except those collected from mid altitude sites (600 and 900 m) that germinated equally well (≥ 75%) after 4and 8-week of clod-moist stratification compared to the other seed lots. The mean germination time was significantly shorter (12 to 19 days, depending on the seed lot) for seeds stratified for 16 weeks than for untreated seeds. It can be concluded that: (1) cold-moist stratification for 16 weeks is the best pre-sowing treatment for breaking dormancy in A. velutinum seeds; and (2) seeds should be collected from mid altitude sites (600 and 900 m) to get more than 80% germination within 15 days, and these seed lots even required shorter cold-moist stratification period(eight weeks) than other seed lots.  相似文献   
52.
Foliar application of nitrogenous organic compounds effects on the quantity and quality of Echinacea purpurea were investigated. This experiment was conducted in a randomized complete blocks design with three replications in growing season of years 2011–2012 and 2012–2013. Treatments included Humiforte (H) and Fosnutren (F) organic fertilizers with concentrations of (0.5, 0.75, 1, 1.5, and 2?L ha?1). Most of the vegetative traits, all of the caffeic acid derivatives measured in aerial parts and roots were significantly affected by foliar application of these nitrogen-contained organic compounds. Generally, best quantitative and qualitative performance belonged to F(2) and F(0.5) treatments, respectively. The application of organic compounds led to significant increase in qualitative and quantitative traits in Echinacea which could be considered as a strategy for increasing medicinal metabolites production in this plant.  相似文献   
53.
The possible role of chitinase in in vitro growth inhibition of the wheat pathogens Fusarium graminearum and Bipolaris sorokiniana by Bacillus pumilus SG2 was investigated. B. pumilus SG2, a chitinolytic bacterium producing two different chitinases, was previously isolated from the saline deserts of Iran. When grown in Spizizen salts medium with colloidal chitin, B. pumilus SG2 secreted two chitinases into the medium, resulting in growth inhibition of F. graminearum and abortion of hyphal elongation of B. sorokiniana. In contrast, when glucose was used as the carbon source, the chitinases were not expressed and antifungal activity of the B. pumilus SG2 was completely abolished. These results confirmed that expression of the B. pumilus SG2 chitinases is under the control of two types of regulation, special regulation by chitin and global regulation by glucose. We demonstrated that chitinases are the main components that caused hyphal inhibition activity of B. pumilus SG2. Hyphal inhibition of F. graminearum and B. sorokiniana was stable in agar for a minimum of 14 days.  相似文献   
54.
A 42‐day trial was conducted to compare the effects of the following seven experimental diets, which varied in black seed, cumin seed, probiotic or prebiotic concentrations, on the broiler chicks: control (no additives), diet BS1 (4 g/kg black seed), diet BS2 (8 g/kg black seed), diet CS1 (4 g/kg cumin seed), diet CS2 (8 g/kg cumin seed), diet Pro (1 g/kg probiotic Primalac®) and diet Pre (2 g/kg prebiotic Fermacto®). A total of 420 1‐day‐old male broiler chicks, initially weighing an average of 43 g, were distributed into 28 floor pens at a stocking density of 15 birds per pen. At 28 day of age, the body weight in the birds fed diets BS2, CS2 and Pro was significantly higher than in the control group, but final body weight was not affected. Additionally, the birds fed diets BS2, Pro and Pre exhibited better feed conversion ratio than control birds from 0 to 42 day of age. Diets BS2, CS2 and Pro also statistically increased the relative weight of thymus and bursa of Fabricius, whereas only diet Pro decreased the abdominal fat percentage compared with control diet. Regarding the haematological parameters, feeding diet BS2 yielded a significant increase in red blood cell count, haemoglobin concentration and haematocrit percentage compared with control diet. Serum total cholesterol and low‐density lipoprotein cholesterol levels in the birds fed diets BS2, Pro and Pre were also significantly lower than in the birds fed the control diet. Without exception, no diets affected feed intake, internal organs weights, carcass characteristics, antibody titres against Newcastle and influenza viruses and leucocyte subsets. In general, current study showed promising results regarding the use of spice additives as growth and health promoters, especially at higher levels of their incorporation in the diets, which were comparable to the probiotic‐ or prebiotic‐containing diets.  相似文献   
55.
Background:This study was devoted to assessing the inhibitory potential of acetone, methanol, and ethanol extracts of Acroptilon repens against disease-associated enzymes, as well as their antioxidant/antibacterial activity and phytochemical composition. Methods:Comparative assessment using various antioxidant evaluation methods, including FRAP, scavenging ability on DPPH radical and hydrogen peroxide, and RP, indicated that the acetone extract presented the highest antioxidant activity, due to its highest total antioxidant content. Results:The TPC and TFC of these extracts were 3.44 ± 0.32 mg GAE/g DW and 2.09 ± 0.2 mg QE/g DW, respectively. The hydrodistillation essential oil from A. repens was analyzed by GC/MS, and 17 compounds were identified. All extracts showed good inhibitory activities against disease-related enzyme acetylcholinesterase and α-amylase, with the lowest IC50 for acetonic extract. Extracts of A. repens exhibited inhibiting activities against the Gram-positive bacteria, with the most effect of acetone extract. Conclusion:Our findings suggest A. repens as a promising source of natural antioxidant, antimicrobial, anti-cholinesterase and anti-amylase agents for the management of oxidative damage, and pharmaceutical, food, and cosmeceutical purposes. Key Words: Acroptilon repens, Antioxidants, Phytochemicals  相似文献   
56.
In this work, the natural dyeing behavior of woollen yarn with madder (Rubia tinctorum L.) root extract was studied. The effects of different tannin-rich plants (Rhus coriaria, Eucalyptus, Terminalia chebula, Quercus castaneifolia, Pomegranate) extract as biomordants and alum (as a chemical mordant) with two mordanting procedures (pre- and metamordanting) on color characteristics of the dyed samples were also investigated. The CIEDE2000 values, color strength (K/S), washing fastness and tensile property of the mordanted and dyed samples were assessed. Visually, a range of hues from orange to brownish-red were obtained. In general, pre-biomordanted samples with Rhus coriaria (10 %owf), Eucalyptus (10 %owf), Terminalia chebula (5 %owf), Quercus castaneifolia (5 %owf) and Pomegranate (5 %owf) showed almost the same color difference (ΔE00) and wash fastness values compared to those treated with 3 %owf alum. Finally, it was concluded from the comparative studies that the biomordants have good potential to be considered as alternatives to the common chemical mordants.  相似文献   
57.
Zinc (Zn) is an essential micronutrient for crop growth. This metal can be found in chemical forms or fractions in the soil. The objective of this study was to investigate the distribution of Zn in special chemical forms using the sequential extraction method after treating eight calcareous soils by zinc sulfate and municipal solid waste (MSW) compost. Zn was separated in seven defined forms as exchangeable (Ex), carbonate (Car), organic (Om), manganese oxide bound (MnOX), amorphous iron oxide bound (FeAOX), crystalline iron oxide bound (FeCOX), and residual (Res). According to the results, the mean concentrations of Zn in chemical forms in untreated soils from higher to lower were 31.84, 8.13, 2.64, 2.57, 0.45, 0.39, and 0.16?mg?kg?1 for the Res, FeCOX, Car, FeAOX, Om, MnOX, and Ex forms, respectively. The total applied Zn to the studied soils from both the sources of zinc sulfate and MSW compost after incubation for 30 days was converted to chemical forms in the following order: Car?>?Res?>?FeCOX?>?Om?>?FeAOX?>?MnOX?>?Ex. On average, 30.3% of total Zn from zinc sulfate and 28.8% of total Zn in the MSW compost were converted into the Car form. The high content of calcium carbonate (CaCO3) in the studied soils is an important factor affecting the conversion of Zn forms, mostly in the Car form through the application of both the inorganic and the organic sources of Zn.  相似文献   
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