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31.
A local isolate of Metarhizium anisopliae (Hypocreales: Clavicipitaceae), Bacillus thuringiensis subsp. kurstaki and chlorantraniliprole were assessed against six field populations of tomato fruitworm Helicoverpa armigera Hübner (Lepidoptera: Noctuidae) in a series of laboratory bioassays. Two dose rates of B. thuringiensis (0.5, 1 μg g?1), one of both M. anisopliae (1.3?×?106 conidia ml?1) and chlorantraniliprole (0.01 ppm) were applied alone and in combination with each other against 2nd, 3rd, 4th and 5th larval instars. The mortality was observed every 24 h until pupation. The bioassays were carried out at 25°C and 75% r.h. The highest mortality was observed in Rawalpindi with the lowest pupation rate by applying the combined concentrations of B. thuringiensis and chlorantraniliprole. The lowest mortality was observed in population from Gujranwala among all the tested populations. The antagonistic interaction was noted where the high dose rate of B. thuringiensis was combined with M. anisopliae; however, the remaining interactions enhanced the mortality and reduced the percent pupation. The overall results demonstrated that all the treatments gave significant control of the larval instars of H. armigera. The population from Gujranwala proved least susceptible whereas the one from Rawalpindi was highly susceptible.  相似文献   
32.
Conservation biology often relies on the protection of (semi)natural habitat remnants. However, the ever increasing human population is taking over natural resources and habitats. Here, contrary to most other studies, we ask how human-associated severe changes in the environment can be used to enrich local biodiversity. We tested if industrial activity (gravel excavation) leads to the creation of habitats that support grassland butterflies and how these areas add to the richness of local species when compared to typical semi-natural habitats (grasslands). We also identified key factors affecting the richness, abundance, diversity and commonness of butterfly species to provide practical recommendations. Species richness, diversity index and the occurrence of rare species were higher in gravel-pit shores than in grasslands. The richness of butterfly species and their abundance were positively affected by the richness of plant species, shrub density and age of the gravel-pit but negatively by the cover of water reservoirs in the surrounding area and the isolation of gravel-pits from grasslands. Butterfly diversity was positively influenced by the richness of plant species and proximity of human settlement but negatively by area of the shore and isolation. Our study is the first one to show the high value of gravel-pits for the conservation of butterflies. We recommend the inclusion of gravel-pits in a system of ecological networks and management of their surroundings to improve the colonization rate of rare species. We suggests that directing interest to the possible positive effects of industrial development on biodiversity may support conservation efforts.  相似文献   
33.
Crops limit light for photosynthesis and growth of weeds. We studied the effect of reduced light on performance of six weed species [one invasive species (Amsinckia micrantha), three common species (Veronica persica, Capsella bursa‐pastoris, Viola arvensis) and two less common weeds (Anagallis arvensis and Scleranthus annuus)]. In two glasshouse experiments, six light levels were achieved aiming at 0%, 20%, 50%, 80%, 90% and 95% reduction of light and corresponding with daily light integrals (DLI) of 12.4, 9.63, 7.13, 2.74, 0.95 and 0.69 mol m?2 day?1 in experiment 1 and 21.2, 18.0, 10.7, 3.71, 1.64 and 1.20 mol m?2 day?1 in experiment 2. The number of leaves was strictly controlled by DLI. Chlorophyll content index, maximum photochemical efficiency of photosystem II (Fv/Fm), stomatal conductance, flowering and dry matter were strongly reduced when DLI was reduced to 0.69–3.71 mol m?2 day?1 for all species. Threshold DLI for flowering was ca. 3.71 mol m?2 day?1 for S. annuus, V. arvensis, A. arvensis and V. persica, while C. bursa‐pastoris deviated by flowering at DLI of 0.95 mol m?2 day?1. This may explain why C. bursa‐pastoris is common in the seedbank of Danish arable soils in spite of intensive farming with well‐fertilised and dense crops.  相似文献   
34.
Sweet cherry (Prunus avium L.) is a self-incompatible species. Determination of the S-genotypes of cherry cultivars is crucial for breeding and to select appropriate cultivars for cross-fertilisation and fruit set. In this study, we characterised the S-genotypes of 25 sweet cherry cultivars, some of which had being bred at the Research and Breeding Institute of Pomology (RBIP), Holovousy, Czech Republic, and others were European cultivars in the RBIP collection. S-genotyping was carried out by polymerase chain reaction using consensus primers for the S-RNase and SFB genes, and capillary electrophoresis. Nine different known S-haplotypes (S1, S2, S3, S4, S5, S6, S9, S13, and S16) were identified and the cultivars were assigned to 12 incompatibility groups. One local cultivar, ‘Pta?ka z Plzně’, originated from a wild forest seedling and used as a pollinator, was assigned to Group 0 of universal donors. The pedigree of some cultivars was confirmed by their S-genotype. This study represents the ?rst comprehensive S-genotype screening of sweet cherry genetic resources in the Czech Republic and will be useful for the design of crossing programmes and orchard management of these sweet cherry cultivars.  相似文献   
35.
In this study, the effects of seven pure plant secondary metabolites (PSM s) on rumen fermentation, methane (CH4) production and rumen bacterial community composition were determined. Two in vitro trials were conducted. In trial 1, nine concentrations of 8‐hydroxyquinoline, αterpineol, camphor, bornyl acetate, αpinene, thymoquinone and thymol were incubated on separate days using in vitro 24‐hr batch incubations. All compounds tested demonstrated the ability to alter rumen fermentation parameters and decrease CH4 production. However, effective concentrations differed among individual PSM s. The lowest concentrations that reduced (<  .05) CH4 production were as follows: 8 mg/L of 8‐hydroxyquinoline, 120 mg/L of thymoquinone, 240 mg/L of thymol and 480 mg/L of αterpineol, camphor, bornyl acetate and αpinene. These concentrations were selected for use in trial 2. In trial 2, PSM s were incubated in one run. Methane was decreased (<  .05) by all PSM s at selected concentrations. However, only 8‐hydroxyquinoline, bornyl acetate and thymoquinone decreased (<  .05) CH4 relative to volatile fatty acids (VFA s). Based on denaturing gradient gel electrophoresis analysis, different PSM s changed the composition of bacterial communities to different extents. As revealed by Ion Torrent sequencing, the effects of PSM s on relative abundance were most pronounced in the predominant families, especially in Lachnospiraceae , Succinivibrionaceae , Prevotellaceae , unclassified Clostridiales and Ruminococcaceae . The CH 4 production was correlated negatively (?.72; <  .05) with relative abundance of Succinivibrionaceae and positively with relative abundance of Ruminococcaceae (.86; <  .05). In summary, this study identified three pure PSM s (8hydroxyquinoline, bornyl acetate and thymoquinone) with potentially promising effects on rumen CH4 production. The PSM s tested in this study demonstrated considerable impact on rumen bacterial communities even at the lowest concentrations that decreased CH4 production. The findings from this study may help to elucidate how PSM s affect rumen bacterial fermentation.  相似文献   
36.
The influence of 50 and 100 μm Ni on membrane integrity, hydrogen peroxide content, lipid peroxidation as well as total fatty acid composition was studied in shoots and roots of wheat seedlings. In both organs, treatment with Ni led to significant increase in electrolyte leakage reflecting the metal‐induced enhancement of membrane permeability. In the shoots, it was accompanied by significant increase in lipid peroxidation. Accumulation of hydrogen peroxide, more pronounced in the shoots, was also found in Ni‐treated wheat. Exposure of wheat seedlings to Ni altered the total fatty acid composition, leading to decrease in their unsaturation, which was indicated by reduction in double bond index. In both organs, a significant decrease in linolenic acid (C18 : 3) content was observed. It was accompanied by increased linoleic (C18 : 2) and oleic (C18 : 1) acid contents in shoots and roots, respectively. In the shoots, parallel increase in palmitic acid (C16 : 0) and decrease in palmitoleic acid (C16 : 1) were found at the end of the experiment. Our results suggest that modification of fatty acid profile in Ni‐treated wheat seedlings is partly related to lipid peroxidation and increased electrolyte leakage and may reflect damage of cells caused by the metal.  相似文献   
37.
Many benzimidazoles are known inducers of cytochromes P4501A (CYP1A) in laboratory animals and cell lines. As flubendazole and mebendazole are benzimidazole anthelmintics often used in a pheasant, in the present study an effect of these drugs in primary cultures of pheasant (Phasianus colchicus) hepatocytes was investigated. After 48 h incubation of the hepatocytes with the benzimidazoles (0.2-5 microM), CYP1A activities -- ethoxyresorufin O-deethylation (EROD) and methoxyresorufin O-demethylation (MROD) activities were measured and the CYP1A protein levels were determined by Western blotting. None of the tested benzimidazoles influenced the CYP1A protein content. No pharmacologically significant enhancement of CYP1A after exposure of the hepatocytes to flubendazole and mebendazole was found. Inhibition of the EROD/MROD activities caused by both tested substances was observed only at the highest concentration (5 microM). From a point of view of CYP1A induction or inhibition, the treatment of pheasants by both anthelmintics tested seems to be safe. Our study demonstrates the inter-species differences in CYP1A inducibility and the importance of induction/inhibition studies on target animals.  相似文献   
38.
In the present study, the influence of two different PGRs, indoleacetic acid (IAA) and kinetin (Kn) on immune potential enzymes, adenosine deaminase (ADA) and myeloperoxidase (MPO), and antioxidant defense enzymes such as glutathione peroxidase (GPx), glutathione reductase (GR), and superoxide dismutase (SOD) in various tissues of rats were investigated during the treatment as a drinking water model. 100 ppm of IAA and Kn as drinking water were administered orally to rats (Sprague-Dawley albino) ad libitum for 21 days continuously. The PGRs treatments caused different effects on the immune potential and antioxidant defense enzymes of experimented rats compared to controls. Results show that IAA caused a significant decrease in GR activity in the lungs and liver and an increase in the spleen. Also, IAA caused a significant decline in GPx activity in the lungs and an increase in the heart. SOD was significantly reduced in the heart, while increased in the lungs. Furthermore, IAA caused a significant decrease in ADA activity in the heart and blood whereas an increase in the kidney and spleen. MPO activity was also significantly increased in the heart by IAA treatment. The activity of enzymes were also seriously affected by Kn; GR activity decreased in the lungs, brain, and blood while GPx activity decreased in the spleen, brain, and heart. ADA activity was also significantly reduced in the blood whereas MPO activity rose in the spleen. In addition, SOD activity lowered in all tissues except for lungs where a significant increment was determined. As a conclusion, the results indicate that PGRs might affect on antioxidant and immune potential enzymes. These data, along with the determined changes suggest that PGRs produced substantial systemic organ toxicity in the erythrocyte, liver, brain, heart, lungs, spleen, and kidney during the period of a 21-day subacute exposure.  相似文献   
39.
The aim of the present study is to reveal the anatomical structure of lumbosacral plexus of barn owl. Six barn owls were included in the study. Nerves originating from plexus were dissected individually, and findings of innervation areas of nerves were determined. Lumbosacral plexus of barn owl was observed to be formed by ventral rami of ten synsacral spinal nerves. It was found that while the r. cutaneus femoris lateralis, the n. obturatorius, the n. coxalis cranialis, the r. cutaneus femoris medialis, the n. cutaneus femoris cranialis and the n. femoralis originated from the lumbar plexus, the n. isciofemoralis, the n. cutaneus femoris caudalis, the n. coxalis caudalis and the n. ischiadicus originated from the sacral plexus. Consequently, when the results of the study were compared with information of different avian species, it was observed that differences focused on the formation of the lumbar and sacral plexuses and innervation level of digits.  相似文献   
40.
Ozone concentrations were measured at a wind-exposed edge of a 60 year-old 15–20 m tall Norway spruce forest in south-west Sweden and simultaneously over a barley field 5 km away for 27 days, At the forest site, measurements were performed at 3 and 13 m height 15 m in front of the forest edge, at 3 m height 15 m into the forest, and at 3 and 13 m height 45 m into the forest. Measurements at 3 m were made with three replicate tubes separated by 10 m. Differences between replicates were small. At 13 m height, the concentration (24-hr-average) 45 m into the forest was 95% of that in front of the forest edge. The average concentration at 3 m height did not vary strongly with the distance into the forest, but was 86% of that at 13 m in front of the forest edge. For AOT40 (Accumulated Exposure Over Threshold 40 ppb ozone), the differences between different positions were larger. At the 13 m level the AOT40 (day and night) was 88% of that in front of the forest 45 m into the forest. The AOT40 at 3 m was 71% of that at 13 m outside the forest. At the crop site, the ozone concentration at 1.1 m (0.1 m above the canopy), was 78% of that at 9 m (06.00–22.00). The AOT40 at 1.1 m above the ground, however, was only 50% of that at 9 m, indicating that serious errors can arise if ozone monitoring data are used uncorrnected in dose-response relationships based on measurements performed at plant height. The ozone concentration for the whole period differed very little between 9 m height at the crop site and 13 m height at the forest site outside the forest during daytime conditions (06.00–22.00). Night-time (22.00–06.00) values were only 21% at the crop site of those at the forest site due to the stronger night inversion development in the agricultural environment compared to the wind exposed forest edge. The results suggest that variations in topography and vegetation are important to consider when combining ozone monitoring data with dose-response functions.  相似文献   
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