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171.
Pea powdery mildew is one of the major constraints in pea production worldwide, causing severe seed yield and quality loss. The resistance is governed by a single recessive gene er1 in majority of resistant cultivars, but er2 and Er3 have also been reported. The objective of the study was to find out tightly linked sequence characterized amplified regions (SCAR) markers to er1 gene using NILs. A total of 620 random amplified polymorphic DNA (RAPD) markers were screened for length polymorphism between seven sets of NILs. The 880 bp polymorphic band of the tightly linked RAPD marker OPX 04880 was cloned, sequenced and a SCAR marker ScOPX 04880 was developed. In a population of completely classified 208 F2 plants (supported by phenotypic data from 208 F2:3 and 4,390 F3:4 families) ScOPX 04880 was linked at 0.6 cM in coupling phase with er1 gene in the order ScOPX 04880er1–ScOPD 10650. ScOPX 04880 will correctly differentiate homozygous resistant plants from the susceptible accessions with more than 99 % accuracy. In combination with repulsion phase marker ScOPD 10650, ScOPX 04880 can help in an error free marker-assisted selection.  相似文献   
172.
Populus species are important resources for industry and in scientific study on biological and agricul-tural systems. Our objective was to enhance the frequency of plant regeneration in Himalayan popla...  相似文献   
173.
Summary Genetically stable artificial autotetraploids with over 90% seed set were obtained by colchicine treatment of the solanaceous species Hyoscyamus niger L. (2n=4x=68). The tetraploids were vigorous and yielded 22.5% more tropane alkaloid per individual than the source diploids.CIMAP Publication No. 35/90  相似文献   
174.
Summary Some photosynthetic characters as-leaf anatomy, leaf photosynthetic rate and CO2 compensation pointdistinguishing C3 and C4 plants and physiological characters as leaf area ratio, nitrogen content, leaf stem ratio and total shoot-to-root and deep root-to-shoot ratios have been studied in rice × sorghum and rice × wheat hybrids. Rice × sorghum 1. has lower values of photosynthetic rate, leaf nitrogen, total root and deep root-to-shoot ratio and CO2 compensation point as of rice parent where as, rice × sorghym 2. is superior in all these characters. Both hybrids lack kranz anatomy. Though both rice × sorghum hybrids show characters of C3 rice plant but rice × sorghum 2. has improved drought tolerance and leaf characters in relation to yield. Rice × wheat hybrid have higher assimilatory area and higher total root-to-shoot ratio. Grains of rice × wheat hybrids are identical to rice grain. However, as grains of rice × wheat hybrid does not contain seed coat, it could be exploited as novel rice germplasm after improvement.Abbreviations T CO2 compensation point - T21 CO2 compensation point at 21% O2 - T2 CO2 compensation point at 2% O2 - dR/sR deep Root-to-shoot Ratio - LAR Leaf Area Ratio - CER photosynthetic rate - TR/SR Total Root-to-Shoot Ratio  相似文献   
175.
 ZnSO4, Zn-enriched farmyard manure (Zn-FYM), Zn-tetraammonia complex sorbed on FYM [Zn(NH3)4-FYM] and Zn-ethylenediaminetetraacetate (Zn-EDTA) were compared as Zn sources for rice production under lowland conditions. The amount of Zn supplied by Zn-EDTA was one-tenth of that supplied by the other Zn sources. Zn application to a Zn-deficient soil corrected the visual symptoms of Zn deficiency and significantly increased the total biomass, grain yields and the harvest index of rice, as well as the Zn concentration in the grain and the uptake of Zn by the straw and the grains. Even with lower rates of application (0.25 and 0.5 mg Zn kg–1 soil), Zn-EDTA treatments gave comparable values for these parameters, and the highest "Zn-mobilization efficiency" compared to the other Zn sources. The content of diethylenetriaminepentaacetate (DTPA)-extractable Zn in the soil of the different treatments after the harvest of rice was in the order; ZnSO4=Zn-FYM>Zn(NH3)4-FYM=Zn-EDTA. The application of Zn also significantly increased the number of panicles that emerged between 80 to 93 days after transplanting, though the total number of panicles at harvest remained unaffected. The calculated panicle-emergence index had a positive correlation with the grain yield of rice. The Zn-EDTA treatment, inspite of supplying the lowest amount of Zn, as well as leading to the lowest rate of Zn uptake, produced the highest yields. Therefore, we concluded Zn-EDTA to be the most efficient source of Zn for lowland rice production. Received: 20 October 1998  相似文献   
176.
Emerging multiple nutrient deficiencies have necessitated renewed efforts to address nutrient management issue through integrated use of inorganic fertilizers (IF), organic manures (OM), and microbial consortium (MC). Accrued long term field experiment data on evaluation of integrated nutrient management (INM) in Nagpur mandarin (Citrus reticulata Blanco) carried out with the objective of working out an efficient INM module grown on Vertic Ustochrept showed much better effectiveness of MC when used in combination with IF fertilizers and OM, farmyard manure (FYM) or vermicompost (Vm). However, the latter could produce a much higher magnitude of response. The net increase in canopy volume within four years (2007–2012) with 100% recommended dose of fertilizers (RDF) was much higher compared with 75% RDF plus 25% Vm plus MC, with significantly better fruit quality parameters. Soil quality parameters in terms of soil microbial biomass (SMB) and soil microbial biomass nutrients (SMBN) were much higher with 75% RDF plus 25% Vm plus MC as compared with exclusive use of IF as 100% RDF. These changes within rhizosphere were very well translated into consequent improvements in leaf nutrient composition, being significantly higher with 75% RDF plus 25% Vm plus MC over 100% RDF. These observations warranted strong support in favor of INM-based treatments than sole use of IF.  相似文献   
177.
Water, Air, & Soil Pollution - Rain water samples were collected at New Delhi during the monsoon of 1994 at a height of 30 m above the ground level using a wet-only collector. Simultaneously,...  相似文献   
178.
Rain water samples of equal volume (50 mL) were collected from two couvective showers at New Delhi on 28 July and 23 August during the monsoon, 1994. The variation of constituents of both the showers showed different trends which might have been due to different antecedent periods. The first shower occurred after an antecedent period of 2–3 hours while the second shower occurred after a 14 day interval. The first shower had acidic pH (<5.6) and relatively higher concentration of NH4, SO4, NO3, Cl, F and K indicating insignificant below cloud scavenging. The second shower had alkaline pH (>5.6) and relatively higher concentrations of Ca and Mg. The higher concentration of Ca and Mg in the second shower were due to the loading with particulate matter during the preceding 14 days which made below cloud scavenging significant.  相似文献   
179.
180.
Solvent extracts from the aerial and root parts and seed oil from E. sativa (rocket salad) were assayed for anticancer activity against melanoma cells. The seed oil (isothiocyanates rich) significantly (p < 0.01) reduced the tumor growth comparable to the control. Remarkably, the seed oil inhibited melanoma growth and angiogenesis in mice without any major toxicity. The findings qualify seed oil for further investigations in the real of cancer prevention and treatment.  相似文献   
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