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61.
Success of a baculovirus in the field depends on the selection and utilization of effective isolates of viruses with increased pathogenicity and virulence. Isolates ofPlutella xylostella granuloviruses collected from Kenya and India were compared for genetic variations by restriction endonuclease enzyme analysis and for biological activity based on their median lethal concentration and time-to-kill early- and late-third instars. TheP. xylostella granulovirus isolates in Kenya were more diverse than those in India and were considerably different from the latter, with only 53–61% similarity. The Kenyan and Indian isolates did not differ significantly for their median lethal concentration, but the Kenyan isolate collected from Kibwezi was significantly faster than other isolates in killing early- and late-third instarP. xylostella. Cluster analysis of restriction fragment marker profiles of theP. xylostella granulovirus with other granuloviruses revealed that it grouped into a cluster with Spodoptera litura granulovirus, whereasHelicoverpa armigera andChilo infuscatellus granuloviruses grouped into another cluster. Results of the present study indicate the existence of genetically and biologically diverse isolates ofP. xylostella granulovirus which could be further developed into effective biopesticides for the management of diamondback moth. http://www.phytoparasitica.org posting May 21, 2008.  相似文献   
62.
It is an important task of people connected with the textiles and clothing sector to work on the feasible ways to trim down the carbon footprint in each phase of a textile product??s life cycle. One of the possible ways to decipher the reduction of carbon footprint of textiles and clothing sector is to recycle the textile process waste and also to recycle at the end-of-life of textile products and these aspects are exemplified in this paper in detail. Detailed investigation of the possibilities, barriers, challenges to recycle textile waste materials are discussed in this paper with relevant case studies. For recycling of process waste, an example was modelled by recycling the process waste and the carbon footprint results were demonstrated with the aid of 7.3 version of SIMAPRO LCA (Life cycle assessment) software. From the results of this case study, it was understood that recycling of process waste would contribute to the direct reduction of carbon footprint. For the second case of recycling at the end-of-life, there are many barriers and challenges to the textile products to be recycled, which are discussed in detail. For this case, two hypothetical situations were defined and the carbon footprint results of them were modeled and demonstrated with the aid of 7.3 version of SIMAPRO software to illustrate the benefits of recycling to reduce the carbon footprint. Designers need to conisder, ??Ecological Design?? in design phase to address most of the difficulties faced by recycling of textile products at the end-of-life, which will of certain help to reduce the carbon footprint of the textile products.  相似文献   
63.
64.
Northern shrimp (Pandalus borealis) oil, which is rich in omega-3 fatty acids, was recovered from the cooking water of shrimp processing facilities. The oil contains significant amounts of omega-3 fatty acids in triglyceride form, along with substantial long-chain monounsaturated fatty acids (MUFAs). It also features natural isomeric forms of astaxanthin, a nutritional carotenoid, which gives the oil a brilliant red color. As part of our efforts in developing value added products from waste streams of the seafood processing industry, we present in this paper a comprehensive characterization of the triacylglycerols (TAGs) and astaxanthin esters that predominate in the shrimp oil by using HPLC-HRMS and MS/MS, as well as 13C-NMR. This approach, in combination with FAME analysis, offers direct characterization of fatty acid molecules in their intact forms, including the distribution of regioisomers in TAGs. The information is important for the standardization and quality control, as well as for differentiation of composition features of shrimp oil, which could be sold as an ingredient in health supplements and functional foods.  相似文献   
65.
During the summer months, Adélie penguins represent the dominant biomass of terrestrial Antarctica. Literally millions of individuals nest in ice-free areas around the coast of the continent. Hence, these modern populations of Adélie penguins have often been championed as an ideal biological indicator of ecological and environmental changes that we currently face. In addition, Adélie penguins show an extraordinary record of sub-fossil remains, dating back to the late Pleistocene. At this time, temperatures were much lower than now. Hence, this species offers unique long-term information, at both the genomic and ecological levels, about how a species has responded to climate change over more than 40 000 years.  相似文献   
66.
The high growth-stimulating effect of plant extract has urged the plant biotechnologists to use natural supplements in the culture media instead of synthetic phytohormones. We advocated the effect of sprouted sorghum extract(SSE) on emergence, in vitro acclimatization, and genetic fidelity in coleoptile derived callus of indica rice variety ADT36. The use of SSE with Murashige Skoog medium efficiently acclimatized the root and shoot apical systems. A higher mat and seminal roots(3.4 g biomass) with an efficient shoot primordium elongation were observed with an increase in the concentration of SSE. Seeds treated with SSE medium showed higher germination and earlier coleoptile maturation about 48 h compared to untreated seeds, and there was a higher expression of e EF-1α with an increase in coleoptile length. B5 medium was effective on inducing embryogenic and nodular callus from 3-day-old coleoptile with 3.0 mg/L 2,4-dichlorophenoxyacetic acid and further proliferated effectively with 0.8 mg/L kinetin with a fresh weight of 180 mg. Highly significant regeneration was observed with combination of 2.5 mg/L 6-benzylamino purine and 3.0 mg/L α-naphthaleneacetic acid. The metabolic and genetic profiles of in vitro and directly cultivated plants were the same, examined through Fourier-transform infrared spectroscopy, random amplified polymorphic DNA(RAPD), inter-simple sequence repeat(ISSR) and R-ISSR(combination of RAPD and ISSR) markers, respectively, and thus confirming the significant efficacy of the SSE incorporated medium. Disarmed T-DNA was transformed to coleoptile derived callus through Agrobacterium tumefaciens LBA4404 and confirmed by GUS assay. The T-DNA integration was confirmed by DNA blot analysis using DNA from transient GUS-expressed explants. Thus, SSE can be used as a natural and organic supplement for organogenesis and efficient acclimatizations of shoot and root apical meristems in regenerated plants.  相似文献   
67.
Zinc (Zn) use efficiency hardly exceeds 2–3% and major portion of added Zn gets fixed in the soil. In order to improve the Zn use efficiency by crops, a laboratory study was undertaken at the Department of Nano Science and Technology, Tamil Nadu Agricultural University, Coimbatore, India, to develop Zn fertilizer using nano-zeolite as a substrate. The natural zeolite (clinoptilolite) was ball milled to achieve nano-dimension (90–110 nm) and fortified with Zn by loading Zinc sulphate (ZnSO4). The zeolite was characterized before and after loading of Zn using particle size analyzer, Fourier Transform Infrared Spectroscopy, Raman Spectroscopy, X-ray Diffraction, Scanning Electron Microscope and Transmission Electron Microscope. The data clearly indicated that the nano-zeolite was loaded successfully loaded with Zn to the tune of 14% and Zn presence in the substrate was confirmed by Energy dispersive X-ray spectroscopy and Atomic Force Microscopy. After the synthesis, sorption and desorption pattern of Zn of the nano-zeolite was examined using a percolation reactor. The results showed that Zn release from the nano-zeolite substrate has prolonged for a period of 1,176 hrs, while the Zn release from the ordinary ZnSO4 ceased to exist within 216 hrs. The data suggest that the nano-sized zeolite is capable of retaining Zn and slowly release into the soil solution, which may be served as a slow release Zn fertilizer and improve use efficiency by crops.  相似文献   
68.
The melon fruit fly, Bactrocera cucurbitae (Coquillett) poses a serious threat to cucurbit production worldwide. Its management by conventional means remains difficult due to their proclivity to oviposite in fruit. In view of the increasing environmental safety concerns, use of biocontrol agents for sustainable pest control holds immense potential. Given this, the study intended to identify the cultivable bacteria inhabiting the intestinal tract of adult male and female melon fruit flies (Bactrocera cucurbitae) separately from field-collected population, and to assess the attractiveness of these bacteria to the fly. All selected bacterial isolates were identified and characterized based on morphological, biochemical and 16S rRNA gene sequence. Bacterial community identified in the gut of B. cucurbitae predominantly composed of Enterobacteriaceae followed by Staphylococcaceae, Enterococcaceae, Bacillaceae and Brucellaceae. Further, the laboratory bioassay was employed to examine the attractiveness of the supernatant as well as whole culture broth of 10 different species of bacteria to B. cucurbitae adults. Among these, Klebsiella oxytoca and Citrobacter freundii followed by Bacillus cereus were found highly attractive to fruit flies. The field experiment using supernatant of two bacteria demonstrated that the K. oxytoca was significantly more attractive to female flies followed by C. freundii.  相似文献   
69.
In vertebrates, many studies verified the immunomodulatory effect of melatonin in various tissues. Its exact role in lower organisms like insects has been very sketchy. The present study deals with understanding the immunomodulatory effect of melatonin in pesticide exposed insects. Total hemocyte count, Differential hemocyte count, Prophenoloxidase activity, and nodulation mechanism at different time intervals were studied. Results showed the abamectin results in significant increase (p < 0.01) in haemocytes numbers at 6, 48, and 72 h. Abamectin toxicity was counteracted by melatonin, with decreasing the hemocytes at 2, 4, and 12 h. Prophenoloxidase activity and protein content (p < 0.001) at 48 and 72 h of Melatonin + abamectin were slightly decreased. There was a significant decrease in nodule formation in 12–24 h in melatonin treated groups and it was clearly visible at 6 h. Increased Prohemocytes, Plasmatocytes, and Oenocytoids numbers decline in melatonin treatment. Melatonin treatment increased the survival rate on pesticide exposed insects. Results suggest that melatonin exposure significantly reduces the toxicity in pesticide exposed larvae which in turn brings back immunological profile in a time dependent manner.  相似文献   
70.
A greenhouse experiment was conducted in a red sandy loam soil (Alfisol) to study the responses of arbuscular mycorrhizal (AM) fungus Glomus intraradices Schenck & Smith inoculated (M+) and uninoculated (M−) maize (Zea mays L) plants exposed to various levels of P (15 and 30 mg kg−1) and Zn (0, 1.25, and 2.5 mg kg−1). Roots and shoots were sampled at 55 and 75 days after sowing and assessed for their nutritional status, root morphology, and root cation exchange capacity (CEC) besides grain quality. Mycorrhizal plants had longer and more extensive root systems than nonmycorrhizal plants, indicating that M+ plants are nutritionally rich, especially with P, which directly assisted in the proliferation of roots. Further, root CEC of M+ plants were consistently higher than those of M− plants, suggesting that mycorrhizal colonization assists in the acquisition of nutrients from soil solution. Mycorrhizal inoculated plants had significantly (P ≤ 0.01) higher P and Zn concentrations in roots, shoots, and grains, regardless of P or Zn levels. The available Zn and P status of AM fungus-inoculated soils were higher than unioculated soils. The data suggest that mycorrhizal symbiosis improves root morphology and CEC and nutritional status of maize plants by orchestrating the synergistic interaction between Zn and P besides enhancing soil available nutrient status that enables the host plant to sustain zinc-deficient conditions.  相似文献   
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