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91.
Genetic analysis for growth traits of prolific Garole × Malpura (GM) sheep   总被引:1,自引:1,他引:0  
The FecB gene of Garole sheep was introgressed into non-prolific Malpura sheep to evolve a new prolific sheep strain Garole × Malpura (GM), suitable for semi-arid conditions. The present study was conducted to evaluate the impact of breeding program on production profile of GM sheep and to estimate the genetic parameters for growth traits of GM sheep. Overall prolificacy increased significantly in the new strain as compared to the native Malpura sheep. In the GM flock of F2 and F2 onwards generation 35.31% single, 55.83% twins, 8.16% triplet and 0.70% quadruplets were obtained during lambing. Over the years, prolificacy in the flock has increased significantly. Over all least squares means for birth weight, 3, 6, 9, 12 month weight, pre-weaning gain (ADG1) and post-weaning gain (ADG2) were 1.82 ± 0.03, 9.44 ± 0.18, 14.00 ± 0.24, 16.56 ± 0.33, and 19.32 ± 0.35 kg, and 84.08 ± 1.84 and 35.19 ± 0.99 g, respectively. Majority of the fixed effects had significant influence on the performance traits. The heritability estimates for birth, 3, 6, 9, 12 month weight, ADG1 and ADG2 were 0.30 ± 0.11, 0.22 ± 0.09, 0.23 ± 0.10, 0.27 ± 0.10, 0.30 ± 0.11, 0.17 ± 0.08, and 0.17 ± 0.10, respectively. Modest rate of genetic progress seems possible for these traits under selection. The genetic and phenotypic correlations among different body weights were moderate to high and positive. The genetic correlation of pre and post-weaning daily gains with body weight traits were also high and positive.  相似文献   
92.
The ARL-ATAD (Air Resources Laboratory-Atmospheric Transport and Dispersion) Model is used to calculate trajectories of air parcels leaving New York City, Albany, and Buffalo airshed regions and terminating near Federally-mandated Class 1 areas in the Northeastern United States, for which visibility is protected from degradation under the Clean Air Act. The purpose of this study is to provide an estimate of the frequency of occurrence of trajectory end points terminating over or near these environmentally sensitive regions from data for a one year period. Results indicate that these regions are not substantially effected by the air parcels either on an annual or seasonal basis.  相似文献   
93.
Holotrichia longipennis Blanch. (Coleoptera: Scarabaeidae) is a serious pest of commercial crops in Siduwa, Dhankuta, Nepal. Seven indigenous isolates of entomopathogenic nematodes (Steinernema lamjungense LMT5, S. lamjungense SS4, S. everestense DKP4, S. abbasi CS1, S. sp. KL1, Heterorhabditis indica CK2 and H. indica CK6) were used in a series of bioassays against the insect. All isolates showed an increased dispersal in response to H. longipennis. Nematodes were more attracted towards third instar larvae than to second instars. Differences in penetration and multiplication in the insect were observed amongst the seven isolates. Steinernema lamjungense LMT5, S. everestense DKP4 and S. abbasi CS1 caused greater mortality than other isolates to different developmental stages. Pupae and second instar larvae were more susceptible than third instar larvae. Significant differences were observed in LT50 values of the isolates against different stages of H. longipennis. Three isolates (S. lamjungense LMT5, S. everestense DKP4 and S. abbasi CS1) along with a commonly used insecticide (chlorpyrifos) were tested against this insect in pot and field experiments. In pot experiments using maize and cabbage as a host crop, S. lamjungense LMT5 and S. everestense DKP4 performed better than S. abbasi CS1 and yielded a mortality comparable with chlorpyrifos. Similar results were observed in field experiments 3 weeks after nematode application. These experiments overall suggest S. lamjungense LMT5 to be a promising biocontrol agent against H. longipennis followed by S. everestense DKP4 and S. abbasi CS1.  相似文献   
94.
The effect of iron (Fe) on ureide metabolism was examined in 45‐day‐old pigeon pea (Cajanus cajan L.) (ureide plant) and alfalfa (Medicago sativa) (amide plant). Plants were either inoculated with Rhizobium or fertilized with ammonium nitrate (NH4NO3). The ureides, allantoin and allantoate, and allanotinase activity were increased in pigeon pea with Fe supplementation. Specific effect of Fe on ureide metabolism of pigeon pea was indicated by the lack of same effect in alfalfa under similar conditions. Nitrogenase activity was elevated with increasing concentrations of Fe in pigeon pea (ureide) as well as alfalfa (amide) symbiosis. Nitrogen (N2) fixation, ureides, and allantoinase activity were reduced at 10 ppm and above concentration of Fe.  相似文献   
95.
Bitter-gourd (Momordica charantia L.) cv. ‘Jhallari’ plants were grown in refined sand at graded levels of calcium (Ca) supply ranging from acute deficiency (0.02 mM) to excess (8 mM). Apart from the production of characteristic visible symptoms of the respective stresses, deficient (< 4 mM) or excess (8mM) supply of Ca restricted plant biomass and fruit yield. In leaves, the concentration of chlorophyll, Hill reaction activity and the activities of catalase, peroxidase, acid invertase, ATPase, and α-amylase were reduced, but the activity of acid phosphatase was increased by deficiency of Ca. Excess Ca (8 mM) supply significantly reduced the concentration of chlorophyll, Hill reaction activity and the activity of catalase and increased the specific activities of peroxidase, acid invertase, ATPase, α -amylase, and acid phosphatase. Tissue concentration of Ca in leaves and fruits increased with increase in Ca supply from 0.02 to 8 mM. Tissue concentrations in young leaves representing the thresholds of deficiency or toxicity of Ca are found to be 1.12 and 1.98%, respectively. The critical tissue concentration in these leaves suggestive of severe deficiency of Ca is 0.85%.  相似文献   
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98.
The persistence patterns of three synthetic pyrethroids—fenvalerate, tau-fluvalinate, lambda-cyhalothrin—and an organophosphorus insecticide, monocrotophos, on eggplant (Solanum melongena L.) have been evaluated. The extractable residues ranged from 0.05 to 0.45, 0.01 to 0.40, 0.003 to 0.09 and 0.09 to 0.32 μg g?1 for fenvalerate, tau-fluvalinate, lambda-cyhalothrin and monocrotophos, respectively. Fenvalerate was the most persistent among the four, followed by monocrotophos, lambda-cyhalothrin and tau-fluvalinate. The Maximum Residue Limit (MRL) of these pesticides on S. melongena has not yet been documented. The present data may be useful for establishing MRL and assessing the amount of pesticide residues in this vegetable.  相似文献   
99.
The present study aims to reveal the antibacterial potential of the wild mushrooms of Nepal. Despite the recognition of the medicinal potential of the natural resources in this country, a systematic study on the bioactivities of the wild mushrooms is still lacking. Therefore, in an attempt to fill this gap, ethanol extracts of 90 Nepalese wild mushroom samples were tested for antibacterial activity against Staphylococcus aureus and Propionibacterium acnes. Staphylococcus aureus was comparatively more susceptible with Inonotus clemensiae exhibiting the least minimum bactericidal concentration (MBC) of 100 μg/mL. The major compound in I. clemensiae was identified to be hispidin using high resolution liquid chromatography–electron spray ionization mass spectrometry (LC–ESI-MS) and nuclear magnetic resonance (NMR) analyses. Furthermore, the minimum inhibitory concentration (MIC) and MBC values of hispidin were determined to be 25 and 100 µg/mL for S. aureus and P. acnes, respectively. These findings show that the Nepalese wild mushrooms have the potential to be a novel addition to the functional ingredients industry due to their strong antibacterial potential.  相似文献   
100.
To compare production and economic performance of polyculture systems with different species combinations, a 210‐day trial was carried out. In the first combination (T1), milkfish (Chanos chanos) and mudcrabs (Scylla serrata), and in the second (T2), mullets (Mugil cephalus, Liza tade and Liza parsia at 0.5:0.5:0.5 ratio) and mudcrabs were stocked keeping fish and mudcrabs at 15,000 numbers per ha, respectively, in both treatments. The finfish were fed floating pellet at 2%–3% and mudcrabs were fed fresh and farm made feed at 5%–8% body weight. Growth parameters of mudcrabs were similar in both T1 (407.64 ± 105.78 g) and T2 (418.89 ± 105.24 g), with no significant differences. Among finfish, M. cephalus attained highest final body weight, 241.55 ± 26.44 g followed by milkfish, 200.46 ± 11.82 g whereas lowest growth noticed in L. parsia (63.69 ± 6.62 g). Length–weight analysis of fish indicated negatively allometric growth (b < 3) for grey mullets, parsia and milkfish while L. tade recorded perfect cube low (b = 2.99). Male mudcrabs recorded positive allometric (b = 3.3) and female crab exhibited negative allometric growth (b = 2.68). The total productivity was 4,533 and 3,694 kg/ha with mudcrab contributes 53.69% and 60.56% to the total productivity in T1 and T2 respectively. The economic analysis indicated benefit–cost ratio (BCR) of 1.57 and 1.73 in T1 and T2 respectively with 10% and 35% insignificant increase (p > 0.05) in BCR and profit per kg, respectively, in T2 compared with T1. The study elucidates polyculture of mudcrabs with finfish can be a taken up as a profitable venture for sustainable diversification of brackishwater farming in Sundarbans.  相似文献   
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