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51.
Saswati?Nayak Radha?PrasannaEmail author Anjuli?Pabby T.?K.?Dominic P.?K.?Singh 《Biology and Fertility of Soils》2004,40(1):67-72
Nitrogen fixing potential in terms of acetylene reducing activity (ARA) and biomass accumulation (in terms of chlorophyll) were investigated using surface and below-surface soil cores, collected from rice fields 45 and 90 days after transplanting (DAT). Treatments included different levels of urea (30, 60, 90 and 120 kg N ha–1) in combination with inoculation using blue green algae (BGA) and Azolla biofertilizers. Application of biofertilizers brought about a significant enhancement in chlorophyll accumulation and nitrogenase activity, when measured 45 DAT. Positive effects in below-surface soil cores, on both these parameters as a result of application of biofertilizers further emphasized their contribution to the N economy of rice fields. Plots treated with 30 and 60 kg N ha–1 along with biofertilizers exhibited the highest percentage increase in terms of algal biomass and ARA, both in surface and below-surface soil cores at 45 DAT. A definite need to examine critically the nature and metabolic activities of below-surface microflora is highlighted through our investigation. 相似文献
52.
A. K. Nayak D. K. Sharma C. S. Singh V. K. Mishra Gurbachan Singh Anand Swarup 《Journal of plant nutrition》2013,36(4):547-556
A survey was conducted for the nutritional status of aonla orchards in the state of Uttar Pradesh lying in Central Indo-Gangetic plains. Preliminary diagnosis and recommendation integrated system (DRIS) norms were established for different nutrient ratios and used to compute the DRIS indices, which assessed the nutrient balance and order of limitations to yield. Maximum fruit yield of 40.2 kg plant?1 was recorded for the plants at the age group of 10–15 years and lowest yield was recorded 28.3 kg plant?1 in the age of above 20 years. Nutrient sufficiency ranges for aonla derived from DRIS norms were 1.30– 1.64, 0.054–0.092, 0.40–0.64%, and 32.4–45.9 ppm for nitrogen (N), phosphorus (P), potassium (K), and zinc (Zn), respectively. On the basis of these sufficiency ranges 33, 51, 47, and 46% of samples were found sufficient whereas 34, 22, 18 and 27% of samples were low and 26, 8, 1 and 17% deficient in N, P, K, and Zn, respectively. When compared age wise, a relative deficiency for N, P, and K corresponding to relative sufficiency for Zn was detected by DRIS technique for the plants above the age group of 15 onwards. For the younger orchards (5yrs old) a relative deficiency of N, Zn, and K corresponding to the relative sufficiency of P was detected. Nitrogen was found most limiting elements in all age group of plant. When the DRIS indices were compared on basis of soil pH, Zn and K was found to be relatively lesser in order of requirement than N and P. 相似文献
53.
Koushik Singha Roy Suvadip Neogi Amaresh Kumar Nayak 《Archives of Agronomy and Soil Science》2013,59(10):1329-1344
In an incubation experiment with flooded rice soil fertilized with different N amounts and sampled at different rice stages, the methane (CH4) and carbon dioxide (CO2) production in relation to soil labile carbon (C) pools under two temperature (35°C and 45°C) and moisture (aerobic and submerged) regimes were investigated. The field treatments imposed in the wet season included unfertilized control and 40, 80 and 120 kg ha?1 N fertilization. The production of CH4 was significantly higher (27%) under submerged compared to aerobic conditions, whereas CO2 production was significantly increased under aerobic by 21% compared to submerged conditions. The average labile C pools were significantly increased by 21% at the highest dose of N (120 kg ha?1) compared to control and was found highest at rice panicle initiation stage. But the grain yield had significantly responded only up to 80 kg ha?1 N, although soil labile C as well as gaseous C emission was noticed to be highest at 120 kg ha?1 N. Hence, 80 kg N ha?1 is a better option in the wet season at low land tropical flooded rice in eastern India for sustaining grain yield and minimizing potential emission of CO2 and CH4. 相似文献
54.
Tripathi Rahul Nayak Amaresh Kumar Dhal Biswaranjan Shahid Mohammad Lal Banwari Gautam Priyanka 《Archives of Agronomy and Soil Science》2013,59(13):1775-1787
ABSTRACTThe present study was to delineate management zones (MZs) in salt affected Mahakalpada block in eastern India by capturing both spatial variability of soil parameters along with satellite derived Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI). Grid wise 237 soil samples collected from the study area were analyzed and spatial maps were generated for physicochemical properties, DTPA extractable micronutrients, i.e. iron, zinc, copper, and manganese and major nutrients, i.e. available nitrogen (AN), phosphorous (AP), and potassium (AK). Soil electrical conductivity and AK showed a high CV of 100% and 56.7%, respectively. Principal component analysis was performed using the soil spatial maps, NDVI and EVI maps and only four principal components which produced eigenvalues > 1 and accounting for 75.4% of the total variability were retained for further analysis. Further, fuzzy c-mean clustering was used to delineate the MZs based on fuzzy performance index (FPI) and normalized classification entropy (NCE) was used for identifying the three MZs. There was a significant difference between MZ1 and MZ2 for all the variables except AN and EVI whereas all the variables were significantly different between MZ1 and MZ3 highlighting the usefulness of MZs delineation technique for site-specific nutrient management. 相似文献
55.
AK Ghosh D Sarkar DC Nayak P Bhattacharyya 《Archives of Agronomy and Soil Science》2013,59(6):583-591
A sequential fractionation scheme, based on a soil phosphorous fractionation, was developed to assess the chemical nature, and thus the potential bioavailability and mobility of As, at the sites. Soil As was separated into five fractions with (i) anion exchange resin, (ii) NaHCO3, (iii) NaOH, (iv) HCl, (v) residual. Most sites contained relatively low concentrations of As in the two most labile fractions. The bulk of the contaminant As at the sites seemed to be associated with soil amorphous Fe and Al minerals and the dominant clay minerals which help in As sorption are montmorillonite and mica. Resin-extractable As in particular might provide a good index of potential As bioavailability and mobility. 相似文献
56.
施氮对香稻某些生理效应的研究 总被引:8,自引:0,他引:8
用1个非和时稻品种Ratna和3个香稻品种HKR228,Basmati370及CBⅡ施氮和不施氮处理对比试验结果,施氮可使稻株光合作用,呼吸作用,植株含氮量提高。但是,施氮对光合作用的促进作用未达差异显著水平。对比非香稻品种Ratna和春稻品种HKR228,施氮对叶片呼吸作用促进作用前者大于后者。 相似文献
57.
Allison L. Kirby Wayne S. Rosenkrantz Rudayna M. Ghubash Blazej Neradilek Nayak L. Polissar 《Veterinary dermatology》2010,21(2):175-183
The objective of this study was to evaluate the level of bacterial contamination of otoscope cones in veterinary private practice, and to determine the most effective method of disinfection. Fifty small animal practices participated in this study, which included a detailed survey regarding otoscope cleaning, storage and usage and quantitative culture of the cleaned and stored otoscope cones. Using sterile technique, two cones from each of the 50 hospitals were swabbed and submitted for quantitative culture. Contamination was present in 29% of the samples and the following organisms were isolated: Flavobacterium brevis (10%), Pseudomonas aeruginosa (6%), Pseudomonas alcaligenes (4%), Staphylococcus intermedius (4%), Corynebacterium spp. (2%), Bacillus spp. (1%), Enterococcus faecalis (1%) Malassezia spp. (1%). There was no statistically significant difference between storage type (dry versus stored in solution) and for the instrumentation used to clean the cones (brush, cotton‐tipped applicator, both versus none). There was a statistically significant difference between the different cleaning solutions (P < 0.001) and between the storage solutions (P = 0.003). A single most effective cleaning solution was unable to be determined due to the large number of solutions utilized. Cetylcide G® (Cetylite Industries, Inc., Pennsauken, NJ, USA) was the most effective of the three most commonly used storage solutions (Cetylcide G®, Benz‐all®, and 2% Chlorhexidine gluconate) when used as directed (P < 0.001). The level of contamination had a positive association with the frequency of cone use and a negative association with the frequency of storage solution replacement. 相似文献
58.
Suvra Mandal Anupam Nayak Manoj Kar Samir K. Banerjee Ashes Das S.N. Upadhyay R.K. Singh Avijit Banerji Julie Banerji 《Fitoterapia》2010
The bioassay guided fractionation of the n-hexane extract of the seeds of Murraya koenigii Spreng (Rutaceae) resulted in the isolation of three bioactive carbazole alkaloids, kurryam (I), koenimbine (II) and koenine (III). The structures of the compounds were confirmed from their 1H-, 13C-, and 2D-NMR spectral data. Of the three compounds (I) and (II) exhibited significant inhibitory activity against castor oil-induced diarrhoea and PGE2-induced enteropooling in rats. The compounds also produced a significant reduction in gastrointestinal motility in the charcoal meal test in Wister rats. 相似文献
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