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41.
Carbendazim was quantified employing reversed-phase high-performance liquid chromatography in rice coleoptiles, radicles and shoot portions of seedlings of different ages grown from seeds treated with the fungicide, and in shoot portions of adult plants at different times after foliar treatment with the fungicide. The highest levels of carbendazim were detected in the coleoptiles four days after germination of seeds and the radicals contained the lowest concentrations. Carbendazim residues declined with time in the shoot portions of seedlings and of adult plants. However, the levels of carbendazim detected in the shoot tissues of 21-day-old seedlings grown from treated seeds [recommended dose of 10 mg a.i. 10g?1 seeds] and in adult plants 35 days after treatment (recommended dose of 0.25 g a.i. litre?1 spray fluid) correspond to the reported lasting ability of the fungicide in terms of protection against blast of rice. 相似文献
42.
Saeed BAGHERIFAM Trevor C. BROWN Christopher M. FELLOWS Ravi NAIDU Sridhar KOMARNENI 《土壤圈》2022,32(5):764-776
Arsenic (As) is a known carcinogen and naturally occurring semi-metal in soils and in the Earth''s crust. Contamination of soils and water with As poses a serious threat to millions of people worldwide due to its health hazards and toxicological properties. Hence, devising novel and efficient methods for remediation of contaminated areas has attracted a great deal of interest across the globe. In this study, we investigated the usefulness of synthetic birnessite, goethite, hexadecylpyridinium chloride-modified montmorillonite (HDPC-M), hexadecylpyridinium bromide-modified zeolite (HDPB-Z), and lanthanum (La)-doped magnetic biochar produced from eucalyptus bark (La-Euchar) as adsorbents at 10% dosage for As stabilization in a soil spiked with 1 000 mg kg-1 As. The effectiveness of the above adsorbents in As immobilization in soil was assessed using single-step extractions with 2 mol L-1 HNO3 and deionized water, the simplified bioaccessibility extraction test (SBET) method, and sequential extraction with the modified Community Bureau of Reference (BCR) method. Application of the adsorbents shifted the exchangeable fraction of As to more recalcitrant fractions and dramatically reduced the exchangeable fraction by 6%-99% and the extractable amounts with HNO3, deionized water, and SBET method by 30%-92%, 17%-95%, and 12%-90%, respectively, compared to the unamended control. The immobilizing effects of adsorbents on As decreased in the sequence of birnessite > La-Euchar > goethite > HDPB-Z > HDPC-M. Birnessite exhibited great affinity for As and drastically reduced As extractability by more than 90% in all single extractions. The results revealed that HDPC-M, HDPB-Z, La-Euchar, birnessite, and goethite are promising immobilizing agents for in situ stabilization of As in terrestrial environments. 相似文献
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44.
Anna Gebruk Polina Mikhaylyukova Maria Mardashova Varvara Semenova Lea-Anne Henry Nikolay Shabalin Bhavani E. Narayanaswamy Vadim Mokievsky 《水产资源保护:海洋与淡水生态系统》2021,31(1):112-125
- The Atlantic walrus, Odobenus rosmarus rosmarus, forms a herd of nearly 4,000 heads in the Pechora Sea (south-eastern Barents Sea). The Near Threatened status of O. rosmarus rosmarus and the relative isolation of the Pechora Sea population, as well as the potential impacts of human activities in the area, make it important to characterize key habitats, including feeding grounds, in order to protect the species.
- The aim of the present study was to integrate multiple sources of environmental and biological data collected by satellite telemetry, remotely operated vehicle (ROV), and benthic grab sampling to examine the distribution and diversity of benthic foraging resources used by walrus in the Pechora Sea.
- Analysis of satellite telemetry data from seven males tagged on Vaigach Island helped to identify areas of high use by walruses near haulout sites on Matveev and Vaigach islands, and in between. Field data were collected from those feeding grounds in July 2016 using ROV video recordings and bottom grab sampling. Analysis of 19 grab stations revealed a heterogeneous macrobenthic community of 133 taxa with a mean biomass of 147.11 ± 7.35 g/m2. Bivalve molluscs, particularly Astarte borealis, Astarte montagui, and Ciliatocardium ciliatum, dominated the overall macrobenthic biomass, making up two-thirds of the total.
- Analysis of 16 ROV video transects showed high occurrences of mobile benthic decapods (3.03 ± 2.74 ind./min) and provided the first direct evidence that areas actively used by walrus in the Pechora Sea overlap with the distribution of the non-native omnivorous snow crab, Chionoecetes opilio.
- Integrating multiple data sources provides an early foundation for the kinds of ecosystem-based approaches needed to improve Pechora Sea resource management and to underpin Russia’s nascent marine spatial planning initiatives. Factors that need to be considered in marine spatial planning include impacts on benthic feeding grounds from offshore oil and gas development and the spread of the snow crab.
45.
46.
Prashant Vikram Jorge Franco Juan Burgueo Huihui Li Deepmala Sehgal Carolina Saint‐Pierre Cynthia Ortiz Vaibhav Kumar Singh Clay Sneller Achla Sharma Maria Tattaris Carlos Guzman Javier Pena Carolina Paola Sansaloni Jaime Amador Campos Serna Karthikeyan Thiyagarajan Guillermo Fuentes Davila Matthew Reynolds Kai Sonder Velu Govindan Marc Ellis Sridhar Bhavani Mohammad R. Jalal Kamali Mozaffar Roosatei Sanjay Singh Daisy Basandrai Navtej Singh Bains Ashwani Basandrai Thomas Payne Jos Crossa Sukhwinder Singh 《Plant Breeding》2021,140(1):87-99
Iranian wheat landrace accessions (IWAs) were collected from country‐wide farm fields and market places in 1935 by a professor at the University of Tehran and shared with University of California at Davis, California. IWAs were further submitted to the genebank of International Maize and Wheat Improvement Center (CIMMYT), Mexico. 2,403 IWAs from CIMMYT’s genebank were assayed by DArT‐seq technology to assess genetic diversity. No apparent ecogeographic patterns related to genetic diversity were detected, probably due to long‐term transport and frequent interchange of landraces among farmers. A multivariate clustering procedure combining genotypic and phenotypic information was used in selecting a core‐set, which represented 15% of the hexaploid wheat accessions included in this study. This subset captured an estimated 93% of rare (frequency <0.05) alleles. Multisite phenotypic data (India, Mexico) validated the ability of the core‐set in detecting useful variants. Potential donor accessions for multiple traits (disease resistance, zinc concentration) were identified from the core‐set for wheat‐breeding. This report illustrates a breeder friendly robust core‐set formulation strategy for harnessing the useful genetic variation stored in the genebanks. 相似文献
47.
Singh Mahendra Babanna Sridhar K. Kumar Dhiraj Dwivedi Ragunandhan P. Dev Inder Kumar Anil Tewari Rama Kant Chaturvedi Om Prakash Dagar Jagdish Chandra 《Agroforestry Systems》2021,95(5):977-993
Agroforestry Systems - This article presents a methodology for the valuation of agroforestry with respect to fuelwood supply for cooking and its opportunity cost. The share of fuelwood consumption... 相似文献
48.
Akkareddy Srividhya Lakshminarayana R. Vemireddy Sakile Sridhar Mudduluru Jayaprada Puram V. Ramanarao Arremsetty S. Hariprasad Hariprasad K. Reddy Ghanta Anuradha Ebrahimali Siddiq 《Journal of Crop Science and Biotechnology》2011,14(1):45-56
Moisture stress is the major constraint to rice production and its stability in rainfed, mainly irrigated, and aerobic environments.
Identification of genomic regions conferring tolerance to stress would improve our understanding of the genetics of stress
response and result in the development of drought tolerant cultivars. In the present study, quantitative trait loci for drought
response related traits and as well as grain yield were identified using a set of 140 recombinant inbred lines derived from
a cross between the popular high-yielding variety, IR64 and the landrace, INRC10192. A total of 36 QTL were identified for
grain yield and its components under control and stress conditions. Strikingly, a QTL cluster flanked by the markers RM38
and RM331 on chromosome 8 was found to be associated with grain yield, plant height, no. of productive tillers, chaffy grains,
and spikelet fertility on secondary rachis and biomass under stress treatment. The genomic regions associated with these QTL
under drought stress will be useful for the development of marker-based breeding for drought tolerant, high-yielding varieties
suited to drought-prone areas. 相似文献
49.
We report on the discovery of a grounding-line sedimentary wedge ("till delta") deposited by Whillans Ice Stream, West Antarctica. Our observation is that grounding-line deposition serves to thicken the ice and stabilize the position of the grounding line. The ice thickness at the grounding line is greater than that of floating ice in hydrostatic equilibrium. Thus, the grounding line will tend to remain in the same location despite changes in sea level (until sea level rises enough to overcome the excess thickness that is due to the wedge). Further, our observation demonstrates the occurrence of rapid subglacial erosion, sediment transport by distributed subglacial till deformation, and grounding-line sedimentation, which have important implications for ice dynamics, numerical modeling of ice flow, and interpretation of the sedimentation record. 相似文献
50.
Bhavani S. Gowda Jennifer L. Miller Sarah S. Rubin Dilram R. Sharma Michael P. Timko 《Euphytica》2002,126(3):365-377
Degenerate oligonucleotides designed to recognize conserved coding regions within the nucleotide binding site (NBS) and hydrophobic
region of known resistance (R)genes from various plant species were used to target PCR to amplify resistance gene analogs
(RGAs) from a cowpea (Vigna unguiculata L. Walp.) cultivar resistant to Striga gesnerioides. PCR products consisted of a group of fragments approximately 500 bp in length that migrated as a single band during agarose
gel electrophoresis. The nucleotide sequence of fifty different cloned fragments was determined and their predicted amino
acid sequences compared to each other and to the amino acid sequence encoded by known resistance genes, and RGAs from other
plant species. Cluster analysis identified five different classes of RGAs in cowpea. Gel blot analysis revealed that each
class recognized a different subset of loci in the cowpea genome. Several of the RGAs were associated with restriction fragment
length polymorphisms, which allowed them to be placed on the cowpea genomic map. The potential for using these sequences to
isolate R genes, and subsequent direct manipulation of disease and pest resistance using genetic engineering is discussed.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献