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991.
Daniel Mailly Mélanie Gaudreault Geneviève Picher Isabelle Auger David Pothier 《Annals of Forest Science》2009,66(2):202-202
992.
Renata Bažok Jasminka Igrc Barèiæ Tomislav Kos Tanja Gotlin Èuljak Martina Šiloviæ Siniša Jelovèan Antonela Kozina 《Journal of pest science》2009,82(4):311-319
The European corn borer (ECB), Ostrinia nubilalis (H?bner) (Lepidoptera: Crambidae), is the major arthropod pest of corn in Croatia. However, chemical control is carried out only in maize for seed production, and in sweet corn. A 3-year investigation was carried out in corn fields in northwest Croatia to establish the most attractive pheromone lure for ECB monitoring, the optimal timing of insecticide applications, and the efficacy of selected insecticides against ECB. During each of the 3 years, the pheromone lures E, Z and E/Z («Isagro») were evaluated in the field from May to July. Insecticides were sprayed 14–20 days after the maximal capture in 2002 and 2003. In 2004, three different trials were set up: one trial with one early treatment (when corn was in the R49 development stage according to the extended BBCH scale); one with one late treatment (when corn was in the R65 development stage according to the BBCH scale); and one with two treatments in both stages. In the trials studying Bacillus thuringiensis var. kurstaki (B.t.k.), insect growth regulators (IGR), spinosad and classical chemical insecticides were applied. Pheromone lure E was the most attractive for monitoring ECB flights throughout 2 years of investigation. Insecticide efficacy depended on application timing. The insecticides most suitable for integrated pest management (IPM) programs, including spinosad, B.t.k. and IGR, resulted in high (spinosad) to moderate (B.t.k.) efficacy. The efficacy of IGRs indicates the need for earlier application. The efficacy of chemical insecticides depended on the year and the insecticide. The organophosphate (OP) insecticides and pyrethroids gave moderate to good results; imidacloprid did not provide significant efficacy. One application of all insecticides based on proper (early) timing resulted in the same efficacy as two applications of the same insecticides. 相似文献
993.
David W Crowder Christa Ellers‐Kirk Bruce E Tabashnik Yves Carrière 《Pest management science》2009,65(3):235-240
BACKGROUND: The insect growth regulator pyriproxyfen has provided effective control of the whitefly Bemisia tabaci Gennadius in many countries. Here, whether or not fitness costs were associated with pyriproxyfen resistance in a laboratory‐selected resistant strain (QC02‐R) of the B biotype was determined. RESULTS: Mortality caused by pyriproxyfen and fitness traits over time were measured in unselected and selected hybrid strains, which were created by crossing individuals of the resistant strain with individuals of a susceptible strain. Fitness costs were not associated with resistance in QC02‐R, as mortality caused by pyriproxyfen did not increase over time in unselected hybrid strains and fitness traits were similar in unselected and selected hybrid strains. Using a new method to examine the inheritance of resistance, based on data from fitness cost experiments, it was estimated that pyriproxyfen resistance is controlled by two loci in the QC02‐R strain. CONCLUSION: The lack of fitness costs associated with pyriproxyfen resistance could promote the evolution of resistance in field populations with similar traits to QC02‐R. Copyright © 2008 Society of Chemical Industry 相似文献
994.
The impact of methodological choices on the outcome of national‐level climate change vulnerability assessments: An example from the global fisheries sector 下载免费PDF全文
Iris Monnereau Robin Mahon Patrick McConney Leonard Nurse Rachel Turner Henri Vallès 《Fish and Fisheries》2017,18(4):717-731
Climate change vulnerability assessments have been receiving increasing attention from policymakers and academics. Given scarce funds for adaptation, the UNFCCC Secretariat has suggested that eligible countries be prioritized for support based on their vulnerability to climate change. National‐level fisheries sector climate change vulnerability assessments as well as other overall vulnerability assessments to date have lent support to the idea that least developed countries (LDCs) are more vulnerable to climate change than small island developing states (SIDS) and other coastal countries. We demonstrate that these perceived differences in vulnerability among country groups are partly due to methodological choices made during these assessments. We argue that national‐level vulnerability assessments, and particularly those dealing with the fisheries sector, often suffer from four main methodological shortcomings: (i) an inconsistent representation of countries belonging to each group, (ii) use of socioeconomic indicators that are not scaled to population size, (iii) use of a small number of indicators and (iv) lack of accounting for potential redundancy among indicators. Building on a previous framework, we show that by addressing the four aforementioned methodological shortcomings, the ranking in fisheries sector vulnerability among SIDS, LDCs and other coastal countries is altered significantly. Our results underscore that the vulnerability of SIDS was partially concealed in previous assessments and suggest that SIDS are in fact the most vulnerable group. Although this study focuses on assessing the vulnerability of the fisheries sector to climate change in SIDS, LDCs and other coastal countries, the implications also apply to other sectors and country groupings. 相似文献
995.
Houwaida Harrabi Françoise Leroi Nourhène Boudhrioua Mihoubi Frédérique Chevalier Nabil Kechaou 《Journal Of Aquatic Food Product Technology》2017,26(3):279-295
Biological silages were prepared from shrimp head and octopus viscera by-products recuperated from the Tunisian seafood industry. Physical and biochemical changes and microbiological profiles were determined for raw materials during fermentation and on end-products. Results showed that biological silage significantly affected (p < 0.05) moisture, protein, and ash contents of shrimp head (CSHS) and octopus viscera silages (COVS). CSHS and COVS were stable, and their final pH values were 4.31 ± 0.01 and 3.71 ± 0.00, respectively. Proteolysis activity was confirmed by a significant increase (p < 0.05) of soluble nitrogen and low molecular weight of protein (<260 Da) found on the end-products for both silages. Lipid oxidation was delayed by addition of 150 ppm ethoxyquin to the raw material prior to fermentation. Biogenic amines detected in raw shrimp and octopus samples decreased significantly (p < 0.05) during the silage process. Histamine and tyramine, detected at high levels on octopus viscera, were absent in the end-products. Tyramine was produced in CSHS, indicating the possibility of the bacterial decarboxylation of tyrosine. Microbiological profiles showed that both silage products were free from pathogenic and spoilage bacteria. Therefore, biological silage can be used as a conservation procedure of shrimp and octopus by-products. The storage period could be shorter than 30 days, and further analysis should be carried out to ascertain safety and nutritional value of silage products. 相似文献
996.
997.
The effect of two training systems (Central Leader with branch pruning versus Centrifugal Training with minimal pruning, i.e., removal of fruiting laterals only) on canopy structure and light interception was analyzed in three architecturally contrasting apple (Malus domestica Borkh.) cultivars: 'Scarletspur Delicious' (Type II); 'Golden Delicious' (Type III); and 'Granny Smith' (Type IV). Trees were 3D-digitized at the shoot scale at the 2004 and 2005 harvests. Shoots were separated according to length (short versus long) and type (fruiting versus vegetative). Leaf area density (LAD) and its relative variance (xi), total leaf area (TLA) and crown volume (V) varied consistently with cultivar. 'Scarletspur Delicious' had higher LAD and xi and lower TLA and V compared with the other cultivars with more open canopies. At the whole-tree scale, training had no effect on structure and light interception parameters (silhouette to total area ratio, STAR; projected leaf area, PLA). At the shoot scale, Centrifugal Training increased STAR values compared with Central Leader. In both training systems, vegetative shoots had higher STAR values than fruiting shoots. However, vegetative and fruiting shoots had similar TLA and PLA in Centrifugal Trained trees, whereas vegetative shoots had higher TLA and PLA than fruiting shoots in Central Leader trees. This unbalanced distribution of leaf area and light interception between shoot types in Central Leader trees partly resulted from the high proportion of long vegetative shoots that developed from latent buds. These shoots developed in the interior shaded zone of the canopy and therefore had low STAR and PLA. In conclusion, training may greatly affect the development and spatial positioning of shoots, which in turn significantly affects light interception by fruiting shoots. 相似文献
998.
Alméras T 《Tree physiology》2008,28(10):1513-1523
Tree stems shrink in diameter during the day and swell during the night in response to changes in water tension in the xylem. Stem shrinkage can easily be measured in a nondestructive way, to derive continuous information about tree water status. The relationship between the strain and the change in water tension can be evaluated by empirical calibrations, or can be related to the structure of the plant. A mechanical analysis was performed to make this relationship explicit. The stem is modeled as a cylinder made of multiple layers of tissues, including heartwood, sapwood, and inner and outer bark. The effect of changes in water tension on the apparent strain at the surface of a tissue is quantified as a function of parameters defining stem anatomy and the mechanical properties of the tissues. Various possible applications in the context of tree physiology are suggested. 相似文献
999.
Thomas Giordanengo Jean-Paul Charpentier Jean-Michel Roger Sylvie Roussel Loïc Brancheriau Gilles Chaix Henri Baillères 《Annals of Forest Science》2008,65(8):803-803
1000.
During a survey on the distribution of Heterobasidion root rot, the North American P group of H. annosum was recorded causing root rot on Aleppo pine, Pinus halepensis, in the gardens of a historical villa in Rome. This is the first report of Heterobasidion root rot on P. halepensis in its natural distribution area, the Mediterranean Basin. 相似文献