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21.
Summary A 6×6 diallel was prepared to study the inheritance of leaf angle in T. aestivum L. Genetic analysis in terms of diallel cross parameters and graphic analysis indicated the control of additive gene effects in the expression of this character. The results of F1 analysis were supported by the analysis of F2 data. 相似文献
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23.
Shaili Srivastava 《Soil biology & biochemistry》2006,38(7):1904-1911
Aspergillus niger isolated from soil of leather tanning effluent had higher activity to remove chromium then the other fungal isolates. The potency of A. niger was evaluated in shake flask culture by absorption of chromium at pH 6, temperature 30 °C. The toxicity of chromium evaluated in petriplates and soil microcosm seed bioassay test had indicated increase in toxicity with the higher concentration of chromate. A. niger introduced in soil microcosm (40% moisture content) with different concentration of chromate (250, 500, 1000, 1500 and 2000 ppm) removed more than 70% chromium in soil contaminated by 250 and 500 ppm of chromate. However, chromium-contaminated soil (2000 ppm of potassium chromate) mixed with compost (5% and 10%) significantly removed chromium in presence of fungus, A. niger. The results of chromate toxicity in the wheat plants revealed that the peroxidases was induced due to increase of metal stress which was reversed in soil microcosm amended with compost. 相似文献
24.
Supply of 0.01 to 1.0 mM Cd acetates either to the intact seedlings or to the excised leaves of 15 dPisum sativum L. Cv. Bonvilla seedlings inhibitedin vivo nitrate reductase activity (NRA), total soluble protein, chlorophyll, and carotenoids. The inhibition was independent of metal concentrations. In excised leaf tissues, higher concentrations (0.5 to 1.0 mM) of Cd had no conspicuous effect on nitrate assimilation. When NRA was assayed byin vitro method, an increase of 12 to 45% was obtained with Cd in intact and excised leaves. It appears that NRA is more sensitive to Cd concentration than any other parameter examined. 相似文献
25.
The Influence of Glutathione on Physiological Effects of Lead and its Accumulation in Moss Sphagnum Squarrosum 总被引:1,自引:0,他引:1
An attempt has been made to study the physiological andbiochemical responses and to evaluate the bioaccumulationpotential of moss Sphagnum to environmental lead. Supply of0.1 to 100 mM lead acetate caused a loss in chlorophyll andnitrogen content of moss and in nitrate reductase activity in themoss, although the peroxidase activity was increased. Partialrecovery in the above parameters was recorded upon simultaneoustreatment with glutathione. Results also indicate that treatmentwith glutathione increased the bioaccumulation potential bylowering the lead toxicity, which could be the result of inductionof metal binding capabilities of cells as the heavy metal alsoinduced the synthesis of phytochelatins. The moss accumulated asignificant amounts of Pb under both experimental and fieldconditions. The heavy metal accumulated by moss was positivelycorrelated to the soil metal content. The experiments demonstratethat Sphagnum is able to accumulate and tolerate higheramounts of Pb and therefore, it can be used as a bioindicator andphytoremediator of lead contaminated environment. 相似文献
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27.
Daily variation in concentration of cortisol in plasma in intact and hypophysectomized gulf killifish 总被引:1,自引:0,他引:1
A daily variation in concentration of cortisol in plasma is synchronized by a 12-hour daily photoperiod in intact as well as in hypophysectomized fish. The daily rhythm in concentration of the adrenal steroid does not depend on a daily rhythm in the concentration of pituitary adrenocorticotropic hormone. 相似文献
28.
Manoj Kumar Solanki Nidhi Singh Rajesh Kumar Singh Pratiksha Singh Alok K. Srivastava Sudheer Kumar Prem L. Kashyap Dilip K. Arora 《Phytoparasitica》2011,39(5):471-481
Tomato root rot caused by Rhizoctonia solani is a major soilborne disease resulting in significant yield loss. The culture filtrates of six isolates of Trichoderma/Hypocrea species were evaluated for in vitro production of hydrolytic enzymes. Results demonstrated that all the six isolates were able to produce chitinase, β-1, 3 glucanase
and protease in the range of 76–235 μmol GlcNAc min-1 mg-1 protein, 31.90–37.72 nmol glucose min-1 mg-1 proteins and 63.05–86.22 μmol min-1 mg-1 proteins, respectively. Trichoderma/Hypocrea-based formulation(s) were prepared with chitin (1% v:v) and CMC (0.5% w:v) for root rot management in a greenhouse. Root dip
application with bioformulation(s) resulted in a significant reduction of the root rot index. In addition, bioformulations
increased plant growth attributing traits significantly relative to untreated control. Accumulation of total phenols, peroxidase,
polyphenoloxidase and phenylalanine ammonia lyase increased in chitin-supplemented Trichoderma/Hypocrea formulation-treated plants challenged with R. solani. The results suggest that chitin-fortified bioformulation(s) could be an effective system to control root rot of tomato in
an eco-compatible manner. 相似文献
29.
S. K. Gupta Anamika Tewari Richa Srivastava R. C. Murthy Saurabh Chandra 《Water, air, and soil pollution》2005,163(1-4):293-302
Vermicomposting of fly ash has been attempted, using red earthworm, Eisenia foetida. Fly ash, which was obtained from thermal power station, was mixed with cowdung in different proportions (20, 40, 60 and 80%). These mixtures were used as feed for earthworms, and after 30 days, vermicast recovery, worm zoomass and numbers of juveniles produced were recorded. A total of six runs each of 30 days were conducted during the whole study. Concentrations of heavy metals in different mixtures of fly ash–cowdung, before and after vermicomposting and in the earthworms used in the study were also estimated. Results show maximum output of vermicasts and maximum number of juveniles produced was in reactors with 40% fly ash while maximum weight gain by earthworm was in 20% fly ash vermireactors. Performance of vermireactors up to 60% fly ash was more or less similar but at 80% fly ash, there is a marked reduction in overall performance of the reactors. Chemical analysis of different samples of fly ash–cowdung mixtures prior to vermicomposting revealed high concentrations of zinc, chromium, lead, nickel and copper. Chemical analysis of vermicomposted samples showed 30–50% reduction in heavy metals up to 60% fly ash and 10–30% reduction in 80% fly ash. Metal analysis of earthworms revealed considerable bioaccumulation of heavy metals in their body. The Present study indicates the feasibility of E. foetida for mitigating the toxicity of metals and up to 60% fly ash–cowdung mixtures can be used for sustainable and efficient vermicomposting. 相似文献
30.
Effects of crop growth and soil treatments on microbial C,N, and P in dry tropical arable land 总被引:1,自引:0,他引:1
We studied the dynamics of microbial C, N, and P in soil cropped with rice (Oryza sativa) and lentils (Lens culinaris) in a dryland farming system. The crop biomass and grain yield were also studied. The microbial biomass and its N and P contents were larger under the lentil than under the rice crop. Microbial nutrients decreased as the crops grew and then increased again. Farmyard manure and NPK fertilizer applications increased the level of microbial nutrients, crop biomass, and grain yield by 35–80%, 55–85%, and 74–86%, respectively. However, these applications had no significant effect on most of the soil physicochemical properties in the short term. The microbial biomass was correlated with the crop biomass and grain yield. The calculated flux of N and P through the microbial biomass ranged from 30–45 and 10–19 kg ha-1 year-1, respectively. Cultivation of a cereal crop followed by a leguminous crop sustains higher levels of microbial nutrients and hence greater fertility in impoverished tropical arable soils. The soil microbial biomass appears to contribute significantly to crop productivity by releasing nutrients, and applications of manure, either alone or with fertilizers, promote this effect more strongly than the application of NPK fertilizers alone. 相似文献