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91.
92.
The aim of this study was to evaluate the diversity and distribution of arbuscular mycorrhizal (AM) fungi in the salt affected soils of Varanasi district. Saccharum munja Roxb. was predominate among all the vegetation and shown strong AM fungal colonisation. Soil characteristics revealed their neutral to alkali nature and habituated six genera and eight different species of AM fungi i.e. Acaulospora (1), Cetraspora (1), Entrophospora (1), Funneliformis (2- F. geosporum and F. mosseae), Glomus (1), Rhizolglomus (2- R. intraradices and R. fasciculatum) in the rhizosphere of native salt tolerant vegetation. Rhizolglomus fasciculatum was the most widely distributed species under strongly alkaline condition (52.96%) while Funneliformis mosseae was well distributed under slightly (22.99%) to moderately alkaline condition (35.78%). Soil alkalinity was observed to be detrimental for AMF but members of family Glomeraceae registered their presence more frequently (~65%) with higher spore density showing strong adaptation which might be helpful in restoration of moderately to strongly alkaline disturbed eco-region.  相似文献   
93.
The effluent collected from the Panipat oil refinery was analysed for different physico-chemical properties. The systematic investigations were carried out to evaluate the effect of refinery effluent on soil fertility by assessing its impact on various soil physico-chemical and biological properties temporally using pot culture experiments. Different concentrations of effluent viz. control, 25%, 50%, 75%, 100% were used for the study. It was observed that application of effluent significantly increased pH, EC, TH, TDS, Ca2+, Mg2+, alkalinity, Cl?, SO42?, Fe, P, Na, K, heavy metals, soil dehydrogenase activity and organic content of soil during all intervals of time except bulk density and specific gravity. On the basis of the study it may be suggested that use of treated oil refinery effluent has no adverse effects on physico-chemical properties of soil and can also be used as an alternate source for irrigating crops as it increases the nutrient content of the soil which is essential for the proper growth and maintenance of crop plants.  相似文献   
94.
Abstract

A study conducted to assess the allelopathic interference of invasive weed Chenopodium album indicated that aqueous leachates of C. album plant parts (roots, whole plant, and leaves), debris extracts and rhizosphere soil deleteriously affected the germination and initial growth of two test plants – Cassia occidentalis (a weed) and Phaseolus aureus (a crop). Further, the plant growth in terms of height, biomass, chlorophyll and protein content was significantly lesser in soil amended with C. album debris. Aqueous leachates, debris extracts, rhizosphere soil and debris amended soil were found to contain significantly higher amounts of water-soluble phenolics – the known phytotoxins. These phytotoxins in root, above-ground parts and leaves were phenolic acids, namely gallic, chlorogenic, caffeic, vanillic, p-coumaric, syringic and ferulic. Among these, chlorogenic acid was present in the maximum amount in the leaves and roots. The study concludes that C. album releases phenolics into the soil and these are probably involved in the growth inhibitory effect of C. album.  相似文献   
95.
[目的]冬小麦一绿肥轮作在干旱贫水年份易导致冬小麦减产,我们研究了平水年和干旱年旱地绿肥和覆膜措施相结合对小麦产量及水分利用率的影响,为建立科学高效的小麦-绿肥轮作体系奠定基础.[方法]田间试验于2017-2019年布设在陕西省永寿县御驾宫乡御中村,试验采用裂区试验设计,以轮作不同绿肥品种(黑麦豆、油菜,夏休闲为对照)...  相似文献   
96.
Some of the factors influencing the propagation of caper (Capparis spinosa L.) plants in vitro and germination of the seed were studied. The number of adventitious shoots emerging from caper stems cultured in vitro increased from 2.2 shoots per explant when the growth medium contained 2 mg/L of gibberellic acid (GA3) to 5.5 when the growth medium contained 2 mg/L zeatin riboside (ZR) and 1 mg/L naphthalene acetic acid (NAA). The best medium for callus formation from leaf and stem parts contained the growth regulators 1 mg/L 6-benzylaminopurine (BAP) and 0.1 mg/L NAA and the best medium for plant regeneration contained 1 mg/L kinetin and 0.1 mg/L indole-3-acetic acid (IAA). The effect of gamma irradiation on the growth of caper shoots in vitro was also studied. A 10 Gy dose of gamma irradiation stimulated growth of shoots up to 200% and increased shoot rooting percentage from 75 to 100%.  相似文献   
97.
98.
R. S. Rana 《Euphytica》1965,14(3):296-300
Successfull application of X-irradiation to obtain viable mutants affecting ray-floret characteristics of annual chrysanthemum is reported. Either strap-shaped flat rays of the control type had strikingly changed in their appearance or were entirely lacking. An interesting mutation resulted in transformation of pistillate nature of the ray florets into bisexual type. The occurrence of mutant phenotypes is genetically accounted for and the usefulness of experimental production of mutations in plant breeding is discussed.  相似文献   
99.
100.
Advanced fry of Indian carps and post-larvae of freshwater prawn were reared for 120?days in 18 small holding tanks using each treatment in triplicate as: (a) non-aerated and (b) aerated fresh human urine (0.01%), (c) cow manure (1.8?kg tank?1), mixed treatment with cow manure and human urine under (d) iso-phosphorus and (e) iso-nitrogenous conditions and (f) control. Examination of water quality, primary productivity of phytoplankton, plankton and fish growth from different treatments revealed that the total fish yield was maximum in the cow manure treatment (621.5?g?tank?1) followed by the mixed treatments under iso-nitrogenous (428?g?tank?1) and iso-phosphorus (333?g?tank?1) conditions. Fish yield in different treatments was the direct function of the gross and net primary productivity of phytoplankton which, in turn, were directly related to the concentrations of nitrate and phosphate levels of water as well as their ratios in different treatments employed.  相似文献   
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