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31.
Most of the natural dyes require mordants for their fixation on textile materials. Natural mordants are thus gaining importance in order to get complete-natural dyeing. In the present work, natural dyes and mordants were extracted using conventional and ultrasound methods and comparative studies were made. The natural mordants namely harda and tamarind seed coat and natural dyes like turmeric, henna were extracted using conventional and ultrasound approaches and various extracts obtained were described in terms of their optical densities. In order to verify the extraction efficiencies, wool fabrics were dyed with extracts of various combinations of mordants/dyes and dyed fabrics were evaluated for their colour strengths and fastness properties. The extent of colour extraction was higher in case of ultrasound assisted extraction as compared to that of conventional method. The fabrics dyed using extracts of ultrasound method showed higher colour values as compared to those dyed using extracts from conventional methods thus confirming ultrasound as more efficient method of extraction.  相似文献   
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Abstract

This is the first report on the antifeedant, toxic and nutritional effects produced by the synthetic chalcones on the lepidopteran Spodoptera frugiperda followed by structure-activity relationship. Bis (5a-c) and mono (8a-d) chalcones have been synthesized via Claisen-Schmidt condensation and have been purified and characterized. The mono chalcones 8b and 8d displayed toxic effects on early larval instars when incorporated to the larval diet at 100?µg per g of diet (40 and 60%, respectively) and low adults emergency with malformations leading to death. The remaining chalcones 8a, 8c, 5a, 5b and 5c do not displayed toxic effects at the same dose. The evaluation of nutritional indices indicated that 8a and 8c were the only tested chalcones to produce decrease in the growth rate and to reduce the efficiency with which larvae converted ingested food into biomass.  相似文献   
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A traditional Type 3 Basmati rice cultivar grown in India is tall and lodges even under low nitrogen fertilizer dose. In addition to lodging, it is highly susceptible to several diseases and pests including bacterial blight (BB). BB resistance genes (Xa21 and xa13) and a semidwarfing gene (sd-1) were pyramided in Type 3 Basmati from a rice cultivar PR106-P2 using marker-assisted selection (MAS). Foreground selection for BB resistance genes, Xa21 and xa13 and reduced plant height gene, sd-1 was carried on the basis of linked molecular markers pTA248, RG136 and ‘h’, respectively. The BC2F3 progenies with both the BB resistance genes were highly resistant with lower lesion length than either of the genes individually. Background profiling of the selected 16 BC2F3 progenies was done using 95 anchored SSR and 12 ISSR markers. Among the selected 16 BC2F3 progenies, 38-5-2 and 38-5-36 closely clustered along with the recipient parent Type 3 Basmati showing above 85% genetic similarity with the same. Further selection was continued till F5 generation for higher recovery for Type 3 Basmati characteristics. The desirable alleles of intermediate amylose content (wx) and aroma (fgr) loci of Type 3 Basmati were also tracked using the linked SSR markers. The BC2F5 pyramid lines T3-4, T3-5, T3-6 and T3-7 homozygous for the three target genes Xa21, xa13 and sd-1 from the donor parent with wx and fgr alleles of Type 3 Basmati had excellent cooking quality and strong aroma.  相似文献   
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Abstract

Poor productivity of rice in rainfed lowlands is due to complete submergence as it is a major abiotic stress of these regions. For enhancing the rice productivity of these areas, better nutrient management options are required and results may even better when combined with stress tolerant cultivars, even when tested under natural conditions of farmers’ field. For supporting the above statement, the effect of nitrogen and phosphorus in graded doses was evaluated for submergence tolerance in controlled conditions and the results obtained were tested and validated at farmers’ field in Cuttack, Odisha, India. Shoot elongation, leaf senescence and lodging were lowest with the application of higher phosphorus (60?kg ha?1). Highest dose i.e. 100-60-40 NPK kg ha?1 resulted in higher plant survival of all the varieties by 90–170% over no nutrient application, it was also reflected in the higher growth after recovery, leaf greenness, leaf and stem growth, chlorophyll and carbohydrate concentrations and ultimately higher grain yield. At farmers’ field, application of basal P, K and post-flood N management practice resulted in overall better performance of Swarna and Swarna-Sub1 showing higher yield attributes leading to 65.7 and 37.9% higher grain yield, over conventional practices followed by farmers. Apart from that results were more positive if post-flood nitrogen was applied as urea foliar spray might be due to quick absorption of N by plant leaves and also spraying helps in removing the silt of flood water sticking to the leaf surface and facilitated the plants to photosynthesize and survive after desubmergence. These cost-effective management options may enhance the productivity and profitability of rice in the flood-prone areas where farmers hesitate to apply nutrients.  相似文献   
35.
Drought stress affects plant growth and causes significant issues in meeting global demand for food crops and fodder. Drought can cause physiological, physicochemical, and morphological changes in plants, which negatively affects plant growth and productivity. To combat this under the increasing global threat of water shortage and rapid population expansion, it is crucial to develop strategies to meet global food demands. Plant growth-promoting rhizobacteria (PGPR) may provide a safe solution to enhancing crop yields through various mechanisms. These soil bacteria can provide drought tolerance to crop plants, allowing them to survive and thrive in water-scarce conditions. Productions of phytohormones, free radical-scavenging enzymes, and stress-combating enzymes that can increase tolerance to drought-induced stress are key features of plant-associated microbial communities. This review summarizes the beneficial properties of microbes that help plants tolerate water scarcity and highlights the bacterial mechanisms that enhance drought tolerance in plants.  相似文献   
36.

Toll-like receptors (TLRs) are pattern recognition receptors (PRRs) that mediate first line of host defence to pathogens. TLR agonists are potent immunostimulatory agents that help to prime a robust adaptive immune response. In the present study, adjuvant potential of Poly I:C and lipopolysaccharide (LPS) were evaluated with live Newcastle disease virus (NDV) vaccine. Cornish chickens were immunized with live Newcastle disease virus (NDV) vaccine (R2B-mesogenic strain) adjuvanted either with Poly I:C (TLR3 agonist) or LPS-TLR4 agonist and both. Humoral Immune response to ND vaccine was evaluated through haemagglutination inhibition (HI) test and ELISA, while the cellular immune response (CMI) was quantified by lymphocyte transformation test (LTT). IL-1β cytokine mRNA levels in spleen tissue were also quantified by real time PCR. The results suggest that TLR3 and TLR4 agonists are an efficient immune-stimulators separately, as LPS co-administered group has shown significantly higher serum titre on second week post-immunization and Poly I:C group on third week post-immunization both by HI and ELISA (P?<?0.01), however, the combined administration of both LPS and Poly I:C did not give any complementary effect on serum titre. There were no significant differences in stimulation indices (SI) and IL-1β cytokine levels between groups at different intervals post-immunization. Hence, TLR agonists LPS followed by Poly I:C could be used as adjuvant to enhance the immune response to NDV vaccine in chicken.

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Spleen samples from 14 mink that were trapped in 4 counties of Nova Scotia were tested for the presence of the Aleutian mink disease virus (AMDV) by polymerase chain reaction. Viral DNA was not detected in samples from Kings County (n = 2), but was detected in all the mink sampled from Colchester (n = 2) and Halifax (n = 6) counties, and 3 of 4 mink from Yarmouth County. The high level of AMDV-infected mink in Colchester and Halifax counties may pose a serious threat to the captive mink and wild animal populations. Because treatment of infected free-ranging mink is not an option, AMDV control strategies for the captive mink should be primarily focused on bio-security to protect clean ranches.  相似文献   
40.
Sugar cane is sensitive to enormous sucrose losses induced by physio-chemical and microbial changes, the severity being increased during the time lag between harvest and crushing in the mills. Minimization of the sucrose losses in the field is essential for better sugar recovery and prevention of sucrose losses. An experiment was conducted to evaluate the efficacy of glutaraldehyde and benzalkonium chloride for their effects on the microbial counts and physio-chemical changes responsible for sucrose losses. Glutaraldehyde and benzalkonium chloride (1000 + 250 ppm) reduced the losses in sucrose content to 7.1% as compared to the 30.8% loss in the control, thus improving the performance by 76.9%. The application of chemicals reduced the acid invertase activity (by 60%), lowered weight loss, titrable acidity, reducing sugars content, dextran, ethanol, and ethylene production and respiration rates. The application led to the reduction in the total bacterial, fungal, Leuconostoc, and yeast counts by 67.92, 51.3%, 26.08, and 51.2%, respectively.  相似文献   
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