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22.
Thirty-four 2-year-old ewes, of which 17 were native (Chokla) and 17 were Avivastra (Chokla 67.5%×32.5% Rambouillet) breeds of similar body weights, were selected. Both groups were maintained under the same management conditions with 8 hours daily grazing. In addition to grazing, each ewe received 300 g/day of a concentrate mixture comprising crude protein 20% and 70% total digestible nutrients. The ewes of both breeds were not mated during the study. The daily environmental parameters were recorded throughout the year, consisting of four main seasons, namely rainy, winter, spring and summer. Blood samples were collected into heparinized tubes during the morning hours for seasonal studies via indwelling jugular vein catheters to avoid stress to the animals, but for the diurnal studies the sampling was done twice daily at 07:00 and 17:00 continuously for three days in each season. Cortisol, thyroxine (T4) and triiodothyronine (T3) were estimated in the samples. The T4 and T3 profiles were maximal in the summer, followed by the rainy season in both groups, with no significant differences. However, the cortisol in both the groups was maximal during the spring rather than the summer. No significant differences were found in T3 concentration between morning and afternoon in any season in the native ewes but these animals showed significantly higher levels of T4 in the morning. The opposite was true for the crossbred animals with regard to both the T3 and T4 profiles. Significantly more cortisol was found in the evening than in the morning in both genetic groups in all seasons. 相似文献
23.
Tapan Adhikari Samaresh Kundu Anangi Subba Rao 《农业科学与技术》2014,(6):468-474
Phosphorus (P) is a major growth-limiting nutrient, and unlike the case of nitrogen (N), there is no large atmospheric source that can be made biologically available. Moreover, P governs crucial role in plant as it stimulates root development and growth, gives plant rapid and vigorous start leading to better tillering and essential for many metabolic processes for seed formation. Soil microbes play very important role in bio-weathering and biodegradation. The microorganisms produce low molecular mass organic acids, which attack the phosphate structure and transform phosphorus from non-utilizable to the utilizable for the plants form. The test of the relative efficiency of isolated strains is carried out by selecting the microorganisms that are capable of producing a halo/clear zone on a plate owing to the production of organic acids into the surrounding medium. It is a well-known fact that as the particle size of rock phosphate decreases, the microbe mediated solubilization of rock phosphate increases in soil. In the present investigation, microbial solubilization of nano rock phosphate (〈 100 nm) particles was studied. Experimental results revealed that Pseudomonas striata solubilized 11.45% of the total P after 24 h of incubation from nano rock phosphate particles while 28.95% and 21.19% of the total P was solubilized by Aspergillus niger (black pigmented) and Aspergillus niger (green pigmented), respectively. It was also observed that Aspergillus niger has the higher ability to dissolve Udaipur rock phosphate than Pseudomonas striata. 相似文献
24.
Sonali Prusty Madhu Mohini Shivlal Singh Kundu Ajay Kumar Chander Datt 《Tropical animal health and production》2014,46(1):65-70
Fifteen male Murrah buffalo calves (15–18 months, 227.98?±?4.44 kg body weight) were distributed randomly in to three equal groups and fed solely on either berseem (G1), oats (G2), or chicory fodder (G3). A digestibility trial followed by methane measurement using SF6 tracer technique was conducted. No significant difference was observed in nutrient intake; however, crude protein (CP) intake was lower in G2 (0.35 kg) than G1 (0.7) and in G3 (0.71) and non-fibrous carbohydrates (NFC), and neutral detergent insoluble CP (NDICP) intake was significantly (p?<?0.05) higher in G3 (1.54 and 0.31 kg) followed by G2 (1.27 and 0.2 kg) and G1 (1.06 and 0.18 kg). The digestible dry matter, organic matter, neutral detergent fiber, and ether extract intake was similar in all the groups, whereas the digestible CP and NFC intake was lower in G2 compared to G1 and G3. Chicory- and berseem-fed groups emitted 12.2 and 5.2 % less methane than oats-fed group. However, no significant difference was observed in the absolute methane loss and methane loss as percentage of energy intake (p?>?0.05) among the groups. There was positive correlation between nutrient intake and total methane production. However, an inverse relationship was observed between total digestible carbohydrate intake and methane production (g/kg dry matter intake). The following regression equations were developed to estimate methane production: methane (g/kg BW) = 128.8553 + (167.7456 × dNDFI) + (216.32 × dCPI) ? (40.3313 × dNFCI) and methane (g/d) = ?1.7494 + (41.42 × NDFI) + (39.8686 × CPI) + (0.5197 × NFCI). 相似文献
25.
Water management decisions are dependent on crop variety, soil and climatic conditions. A properly structured plant growth simulation model which takes these factors into account can be successfully used to quantify the effects of irrigation practices on crop yields. The use of such a simulation model will be considerably less expensive and time consuming than conducting field experiments.This paper reports the results of using such a model for making important water management decisions, such as determining: (a) optimum soil moisture depletion and replenishment levels; and (b) timing and amount of irrigation during different crop growth stages. 相似文献
26.
This study investigated the distribution and characteristics of the Barley yellow dwarf virus (BYDV) species BYDV‐PAS, which was recently separated from BYDV‐PAV, the most commonly studied BYDV species. Throughout 3 years of experimental monitoring of BYDV incidence, PAS was the most frequently occurring species infecting cereals and grasses in the Czech Republic. Furthermore, Rhopalosiphum maidis and Metopolophium dirhodum were recorded as BYDV‐PAS vectors, even though M. dirhodum does not usually transmit BYDV‐PAV. In field experiments with barley and wheat, where virus accumulation, symptoms and effect on the yield were tested, BYDV‐PAV was more severe than PAS. Infection with the BYDV‐PAV isolate resulted in greater expression of symptoms and also in a greater reduction in plant height and grain weight per spike than BYDV‐PAS. In a sensitive cultivar of barley (Graciosa), the amount of viral RNA of BYDV‐PAV was also significantly higher than that of BYDV‐PAS. In a tolerant line (Wbon‐123), however, no such differences were found. In conclusion, although BYDV‐PAS seems to be dominant in the Czech Republic, BYDV‐PAV has the potential to cause more significant crop losses in barley and wheat. 相似文献
27.
Water, Air, & Soil Pollution - This study was conducted to determine the metal (Ag, Al, As, Cd, Co, Cu, Fe, Mn, Ni, Pb, Sb, Zn) tolerance and uptake of Mitchell grasses when grown on waste... 相似文献
28.
S. Kundu Tapan Adhikari S. Rajendiran J. K. Saha A. Subba Rao 《Journal of plant nutrition》2016,39(13):1971-1978
A study was conducted with maize in Vertisol, Inceptisol, Alfisol and Aridisol to evaluate the efficacy of the pine oleoresin coated urea fertilizers (coated with 1.25, 2.50, 3.75 and 5.00% pine oleoresin). Significant increase in biomass yield was observed in all the soils when urea was coated with pine oleoresin at 3.75% or more. All the pine oleoresin coated urea in Inceptisol and Aridisol; and 3.75% and 5% pine oleoresin coated urea in Vertisol and Alfisol significantly increased nitrogen (N) uptake as compared to uncoated urea. Nitrogen use efficiency increased from 19.34% to 32.80% in Vertisol, 13.06% to 28.27% in Alfisol, 13.87% to 23.86% in Inceptisol and 10.68% to 20.23% in Aridisol, as a result of coating urea with pine oleoresin. Thus the results indicate that there is a beneficial effect of coating urea with pine oleoresin with respect to yield, N uptake and use efficiency in maize crop. 相似文献
29.
Sayanti Kundu Avishek Dey Abhijit Bandyopadhyay 《European journal of plant pathology / European Foundation for Plant Pathology》2014,139(3):511-524
Investigations have been carried out to determine the influence of chlorocholine chloride on induction of the resistance mechanisms of Stevia rebaudiana against leaf spot disease, caused by Alternaria alternata. The paper also focuses an impact of chlorocholine chloride induced resistance on reduction of leaf spot disease. Chlorocholine chloride is attributed to its significant role in defence responses through augmentation of phenol and salicylic acid content as well as stimulation of phenylalanine ammonia lyase and peroxidase activity in S. rebaudiana following inoculation with A. alternata. Histochemical studies revealed that fungal invasion as well as infection process was appreciably reduced in chlorocholine chloride treated plants through peroxidase-H2O2 mediated strengthening of cell wall. The overall study highlights the significant role of chlorocholine chloride in induction of resistance in S. rebaudiana against A. alternata. 相似文献
30.
A. Purohit S. Ganguly G. Ghosh R. Kundu Chaudhuri S. Datta D. Chakraborti 《European journal of plant pathology / European Foundation for Plant Pathology》2017,147(1):73-84
Soft rot of Chinese cabbage is a disease of great economic importance to the State of Pernambuco, Brazil. The present study aimed to evaluate the effect of two calcium sources in different concentrations (calcium nitrate [Ca(NO3)2] at 0, 0.15 and 0.3 g l?1 and calcium chloride (CaCl2) at 0, 1 and 5 g l?1) that were applied through two methods (leaf spraying and soil drenching) on the control of soft rot. Further, it aimed to analyze calcium absorption by the plant and to determine calcium’s role in leaf and cell structure using microscopy. Ca(NO3)2 applied by both methods was effective in controlling soft rot caused by Pectobacterium carotovorum subsp. carotovorum, as it reduced the disease by up to 48.5 % when sprayed onto the leaves (0.15 g l?1). A significant increase in the leaf calcium content was observed only in the plants that were sprayed with higher doses of Ca(NO3)2 and CaCl2. In all of the calcium treatments, light microscopy analyses revealed an increased number of chloroplasts and improved structuring of the palisade parenchyma, while transmission electron microscopy analyses revealed an increased cell wall thickness that was especially evident for the 0.15 g l?1 Ca(NO3)2 treatment applied by leaf spraying and soil drenching. 相似文献