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101.
Cowpea, Vigna unguiculata (L.), is an important grain legume grown in the tropics where it constitutes a valuable source of protein in the diets of millions of people. Some abiotic and biotic stresses adversely affect its productivity. A review of the genetics, genomics and breeding of cowpea is presented in this article. Cowpea breeding programmes have studied intensively qualitative and quantitative genetics of the crop to better enhance its improvement. A number of initiatives including Tropical Legumes projects have contributed to the development of cowpea genomic resources. Recent progress in the development of consensus genetic map containing 37,372 SNPs mapped to 3,280 bins will strengthen cowpea trait discovery pipeline. Several informative markers associated with quantitative trait loci (QTL) related to desirable attributes of cowpea were generated. Cowpea genetic improvement activities aim at the development of drought tolerant, phosphorus use efficient, bacterial blight and virus resistant lines through exploiting available genetic resources as well as deployment of modern breeding tools that will enhance genetic gain when grown by sub‐Saharan Africa farmers.  相似文献   
102.
African mangosteen (Garcinia livingstonei T. Anderson) is native to Africa and is exotic to other parts of the world. It is a fruit bearing tree with multiple uses. This study was purposed to determine, by analysis, the chemical compositions and nutritive value of the fruits of African mangosteen. Proximate compositions varied with the portions such as epicarp, mesocarp, endocarp and seed tested. All fruit portions contained carbohydrate (37.67–95.02%) and crude protein (0.65–31.76%) as their major components. Moisture (0.45–3.42%), crude fat (1.23–19.55%), crude fiber (2.93–21.13%) and ash (1.76–5.44%) were also found at different levels, depending upon the portions. All portions of fruit were rich in macro and micro elements. The fruits also possessed phenolics (174.02–10.725?mg GAE per g), flavonoid (19.25 to 99.98?µg QE per g) and alkaloid (1.56 to 9.49?mg/kg) contents. The constitution of tannins and oxalate which contribute towards the anti-nutritive value was also low, thus making the fruits beneficial for consumption. Quality attributes like relative amount of oleic acid, total unsaturated fatty acid, acid value, free fatty acid, peroxide value and iodine value showed that the seed oil of African mangosteen can become one among the oleic acid based vegetable oils for consumption.  相似文献   
103.
Surface active cellulose particles have been prepared for use as foam stabilizing agents in foods. Various sources of cellulose were broken down by combinations of milling, acid dissolution and treatment with cellulase. The most efficient and simple method was hammer and freezer milling of dry crystalline α-cellulose (Tencel). The resultant Tencel particles were made partially hydrophobic through precipitation of ethyl cellulose (EC) onto them in acetone-water dispersions. The optimum ratio of EC to cellulose and the optimum solids concentration (C(x)) at which to form the complexes were 1:1 and C(x) ≈ 1 wt %, respectively. Complexes combined at low concentrations (e.g., C(x) ≈ 0.1 wt %) with caseins or whey proteins gave significant improvements in stability of foams and bubbles to coalescence and disproportionation compared to either component alone. As such, the complexes could be a useful ingredient in improving the quality of various food foams.  相似文献   
104.
Fertigation offers vast potential for efficient use of water and nutrients in sustainable orchard management. Beside minimizing losses, their distribution within the rhizosphere is of utmost importance. In present investigations, most of feeder roots were observed within 30 cm soil depth. Under drip fertigation, wetting front extended horizontally up to 45 cm from emitter. However, the maximum moisture content remained confined within 30 cm distance. Vertically, soil moisture also remained higher in the 0–30 cm soil layers. Under surface irrigation, deeper soil layers registered higher moisture content. Available nitrogen (N) and potassium (K) under fertigation closely followed the moisture distribution pattern. Fertigation plus mulch resulted in 20% fertilizer and 15% water savings over fertigation without mulch. Beside 33% higher fruit yield and 25% water savings, and fertigation plus mulch resulted in 20 percent fertilizer and 40% water savings over surface irrigation.  相似文献   
105.
Suresh Babu  G.  Farooq  M.  Ray  R. S.  Joshi  P. C.  Viswanathan  P. N.  Hans  R. K. 《Water, air, and soil pollution》2003,144(1-4):149-157
Organochlorine pesticides were used earlier for agricultureproduction. Their residues may still be present in soil and mayaccumulate in food crops, posing potential health problems to consumers. DDT, HCH, their isomers and metabolites were analyzedin samples of soil and rice plants collected from ten differentvillages of a well-known Basmati rice growing area in Dehradun.Residues of both pesticides were found in all samples ofsoil and different parts of rice plants except for a few grainsamples. Maximum residue was observed in husk and minimum ingrains. The average concentration of DDT in soil ranged from0.013 to 0.238 ppm. p,p′-DDE was the major metabolite (>63%). Theaverage concentration of DDT in rice grain varied from 0.002 to 0.040 ppm. o,p′-DDT was the main isomer (>93%). Theaverage concentration of HCH in soil ranged from 0.122 to 0.638 ppm. β-HCH was the predominant (43%) isomerfollowed by α-HCH (21%). The average HCH concentrationin rice grain ranged between 0.013 and 0.113 ppm. All four isomers were present in grains. The levels of DDT and CHCin grains were similar in magnitude as those from differentIndian states, but well below the maximum residue limit of 0.1 ppm for DDT and 0.05 ppm for HCH prescribed by the Government ofIndia and WHO/FAO. As such, the pesticide residue levels in thisexport commodity are not of hazardous nature.  相似文献   
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107.
A 2-year study was conducted to determine the effects of tillage and cropping systems on soil moisture balance, growth and yield of pearl millet (Pennisetum glaucum (L.) R.Br.). Three tillage treatments, viz. minimum tillage (one harrowing), conventional tillage (two harrowing, cross) and deep tillage (ploughing followed by two har-rowings), and four cropping systems, viz. monoculture of pearl millet, pearl miliet-clusterbean (Cyamopsis tetra-gonoloba (L.) Taub.) rotation, monoculture of pearl millet with 5 t ha−1 farm yard manure (FYM), and intercropping of pearl millet and clusterbean, were compared. Deep tillage improved the soil moisture storage, water use efficiency and grain yield of pearl millet while consumptive use of water was higher with minimum tillage. Total dry matter yield with deep tillage and conventional tillage was 23.2 and 10.2% higher than minimum tillage in the season 1, and the corresponding values for season 2 were 30.7 and 13.3%. The Pearl millct-clusterbean rotation and monoculture of pearl millet with the application of 5 t ha−1 FYM gave 17.2 and 6.1% higher yield than monoculture of pearl millet, respectively. Maximum water use efficiency was observed in rotation followed by FYM application.  相似文献   
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