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101.
Resistance to spinosad in the western flower thrips, Frankliniella occidentalis (Pergande), in greenhouses of south-eastern Spain 总被引:2,自引:0,他引:2
Bielza P Quinto V Contreras J Torné M Martín A Espinosa PJ 《Pest management science》2007,63(7):682-687
Susceptibility to spinosad of western flower thrips (WFT), Frankliniella occidentalis (Pergande), from south-eastern Spain was determined. LC(50) values of the field populations without previous exposure to spinosad collected in Murcia in 2001 and 2002 ranged from 0.005 to 0.077 mg L(-1). The populations collected in Almeria in 2003 in greenhouses were resistant to spinosad (LC(50) > 54 mg L(-1)) compared with the authors' highly susceptible laboratory strain. The highly sensitive laboratory strain leads to very high resistance ratios for the field populations (>13 500), but these ratios do not necessarily mean resistance problems and control failures (spinosad field rate 90-120 mg L(-1)). The populations collected in Murcia from some greenhouses in 2004 were also resistant to spinosad (RF > 3682). Spinosad overuse, with more than ten applications per crop, produced these resistant populations in some greenhouses. Spinosad showed no cross-resistance to acrinathrin, formetanate or methiocarb in laboratory strains selected for resistance towards each insecticide. Correlation analysis indicated no cross-resistance among spinosad and the other three insecticides in 13 field populations and in nine laboratory strains. The synergists piperonyl butoxide (PBO), S,S,S-tributyl phosphorotrithioate (DEF) and diethyl maleate (DEM) did not enhance the toxicity of spinosad to the resistant strains, indicating that metabolic-mediated detoxification was not responsible for the spinosad resistance. These findings suggest that rotation with spinosad may be an effective resistance management strategy. 相似文献
102.
Gauss CB Dubey JP Vidal D Cabezón O Ruiz-Fons F Vicente J Marco I Lavin S Gortazar C Almería S 《Veterinary parasitology》2006,136(3-4):193-200
Serum samples from 441 red deer (Cervus elaphus) and 161 other wild ruminant species, collected between 1993 and 2005 from six regions of Spain were tested for antibodies against Toxoplasma gondii by the modified agglutination test (MAT). Antibodies to T. gondii (MAT 1:25 or higher) were detected in 15.6% of red deer. Statistically significant differences were observed among sampling sites with seroprevalence in red deer from Catalonia (42.2%) being significantly higher compared with other Spanish regions (8.7%) (P < 0.05). Statistically significant differences were not observed between T. gondii seroprevalence and sex, age or management of hunting estates (open versus fenced). Seroprevalence of T.gondii infection in other ruminants species was 24% of 79 fallow deer (Dama dama), 21.8% of 33 in roe deer (Capreolus capreolus), 33.3% of three Spanish ibex (Capra pyrenaica), 20% of 10 chamois (Rupicapra pyrenaica), 10% of 10 barbary sheep (Ammotragus lervia), and 14.8% of 27 mouflon (Ovis ammon) in areas not including Catalonia, where no samples from these species were available. Serological results indicated a widespread exposure to T. gondii among wildlife in Spain and suggest that consumption of raw or inadequately cooked meat, as well as handling carcasses of wild game, should be taken into account as a source of infection for humans. 相似文献
103.
José M. Olano Miguel A. Zavala Vicente Rozas 《European Journal of Forest Research》2012,131(3):563-570
Enhancement of Juniperus thurifera recruitment and colonisation by oak and pine species has been related at the local level to changes in livestock pressure.
We used forest inventory data from Castilla y León Autonomous Region (Central Spain), an area comprising 34% of the world
range of J. thurifera, to assess whether this process is occurring at a larger scale. We compared tree composition and density in a set of 659
permanent plots over a 10-year period. Logistic models and redundancy analysis were used to assess the effect on this process
of parameters such as livestock pressure, propagule availability and climatic conditions. Between 1992 and 2002, juniper woodlands
became denser (1.31% juniper stem year−1) and tree diversity increased due to rapid colonisation by oaks and pines (2.21% occupied plots year−1). In addition, the presence of juniper increased in other types of forests at a moderate rate (0.6% y−1). Thus, we observed both a disruption of the borders between current forest types and a generalised increase in α-diversity
of tree species. The seed source was the main factor explaining colonisation rate, suggesting that the pace of colonisation
is critically constrained by the spatial configuration of the landscape and the local propagule availability of the colonising
species. If the current colonisation trends continue, monospecific juniper woodlands will become very scarce by the end of
the twenty-first century. 相似文献
104.
Lucía DeSoto Jesús Julio Camarero José Miguel Olano Vicente Rozas 《European Journal of Forest Research》2012,131(4):905-917
Geographically structured tree-ring networks are needed to fully understand the spatiotemporal variability in climatic sensitiveness of trees and to study their future responses to global warming. We aim to identify the spatially constrained structure of radial-growth patterns of the Spanish juniper (Juniperus thurifera L.) and to assess whether their climate–growth responses were unstable during the late twentieth century. Tree–ring width chronologies were built for 13?J. thurifera stands in Spain using dendrochronological methods and related to monthly climatic data. Sites were grouped according to their growth patterns using hierarchical cluster analysis. The relationships among geographical, climatic and stand features and their influence on radial growth were evaluated using redundancy analysis. The climate–growth relationships and their temporal stability were assessed using Pearson’s and moving bootstrapped correlations, respectively. Stands formed three geographical groups according to their high-frequency growth variation: North West and Centre, North East and South East. We found that J. thurifera radial-growth patterns depended on geographical and climatic factors, but not on the stand structure, and responded to a northwest–southeast gradient of decreasing rainfall and influence of Atlantic Westerlies and Mediterranean cyclonic activity. The positive response to June precipitation was unstable during the late twentieth century and started earlier in populations from western mesic sites than in eastern xeric sites. This pattern may be related to either decreasing water availability in western than in eastern sites or the resilience of J. thurifera growth from xeric sites in response to the increasing summer aridity. 相似文献
105.
Most alpine ecosystem climate change studies identify changes in biota, several report abiotic factors and conditions, few report temperature changes, and few to none discuss growing degree days (GDD) changes. This study provides results of data analysis on changes in number of GDD in the alpine desert of the San Luis Valley (SLV) whose community is dominated by an irrigated agricultural region. Analysis indicates significant increases (p?<?0.05) in annual and growing season GDD10, GDD4.4 (potato), and GDD5.5 (alfalfa) during 1994–2007 compared to 1958–1993. With one exception, all stations experienced significant increases in mean annual daily GDD between 0.12 and 0.50 day?2 and growing season GDD day?2 0.21 and 0.81. Higher temperatures increase numbers of GDD, quickening growth of crops and maturity at the cost of reduced yield and quality. Increases in GDD indicate the Valley’s agricultural region and economy may experience negative impacts as yields decrease and water use increases. 相似文献
106.
Cláudia Vicente Margarida Espada Paulo Vieira Manuel Mota 《European journal of plant pathology / European Foundation for Plant Pathology》2012,133(1):89-99
Bursaphelenchus xylophilus, the pinewood nematode (PWN) and causal agent of Pine Wilt Disease (PWD), was detected for the first time, in 1999, in Portugal,
and in Europe. Despite the efforts of the Portuguese National Forestry and Quarantine Authorities, the disease has spread
to new forest areas in the centre of mainland Portugal, in 2008, and to the island of Madeira, in 2009. More recently, two
foci of PWD were reported from Spain. The free circulation of non-treated wood and wood products, as part of global trade,
may explain this phenomenon, which constitutes a threat to other European forestlands. This review gathers the most recent
up-to-date information about PWD in Europe, as well as in other countries, presenting integrative management procedures for
detection and control, and the scientific knowledge generated over the last decade, to understand the complex biological system
behind the disease. 相似文献
107.
Vanaclocha P Vacas S Alfaro C Primo J Verdú MJ Navarro-Llopis V Urbaneja A 《Pest management science》2012,68(7):1092-1097
BACKGROUND: In recent years, environmentally safe measures to control the California red scale (CRS), Aonidiella aurantii (Maskell), have been successfully implemented. These measures include mating disruption (MD) and biological control. The goal of this study was to examine the effect of high concentrations of the CRS sex pheromone on its life history parameters and scale‐cover surface area under controlled laboratory conditions. RESULTS: The developmental time of both males and females of CRS increased with exposure to airborne pheromone. MD had an effect on both the total number of progeny and on the crawler production period for females. Accordingly, demographic parameters such as net fecundity (R0) and intrinsic rate of increase (rm) were significantly lower in the pheromone‐treated populations. The largest scale‐cover surface areas were observed in the CRS reared in the pheromone environment. CONCLUSION: A clear influence of airborne pheromone on the biology of CRS has been demonstrated. In addition to the classical mating disruption benefits of this technique, additional benefits, such as increase in the duration of exposure to natural enemies and increase in size, which benefits some species of parasitoids, have been confirmed. Copyright © 2012 Society of Chemical Industry 相似文献
108.
J. A. Gutiérrez‐Barranquero E. Arrebola N. Bonilla D. Sarmiento F. M. Cazorla A. de Vicente 《Plant pathology》2012,61(4):665-676
Bacterial apical necrosis (BAN), caused by the bacterium Pseudomonas syringae pv. syringae (Pss), is currently the most limiting disease affecting the mango crop in the Mediterranean area. The copper‐based compound Bordeaux mixture (BM) is considered to be the conventional treatment against BAN, but it does not act as a bactericide. Alternative experimental treatments to BM that are compatible with organic farming were tested for their ability to control BAN disease. Field trials were conducted over six seasons in different mango orchards with natural infestation of Pss. The experimental treatments included applications of Silicon gel (a commercial formulation of aqueous potassium silicate), dicalcium phosphate, Kaolinite, and Ulmasud B® (bentonite, powder); BM was applied as the conventional treatment. During the first two seasons (small‐scale trial, 2002–2004), all these experimental compounds were applied in order to select those treatments providing the greatest reduction of BAN symptoms. In the next three seasons (2005–2008), a semi‐commercial scale trial was carried out with the best‐performing treatments, resulting in the selection of Silicon gel. Finally, Silicon gel was tested in a commercial scale trial during the last season (2008–2009). Trees treated with Silicon gel showed significantly fewer necrotic buds and leaves, reaching disease levels very similar to those using the conventional treatment with BM. However, minor differences in P. syringae‐like population levels were observed, as has been described in previous studies. The possible mode of action of the Silicon gel is discussed. Currently, the Silicon gel compound is undergoing the registration process for its commercial use in mango management in Spain. 相似文献
109.
Objectives : The aim of this study was to evaluate the sensitivity of conventional and Doppler ultrasound for differentiation of benign and malignant mammary tumours in female dogs. Methods : Mammary tumours were evaluated from 60 animals and divided into two distinct groups, group 1 (benign tumours) and group 2 (malignant tumours). The tumours were assessed by conventional ultrasound, Doppler ultrasound mode, histopathology and immunohistochemical detection of vascular endothelial growth factor. Results : Conventional ultrasound examination was found to be ineffective in separating tumours into the two experimental groups. Similarly, using colour‐flow Doppler ultrasound, no correlation was found between the presence of vascularisation and its characteristics between the two groups. Triplex Doppler ultrasound yielded average maximum velocities of 28·71 cm/s for malignant and 19·91 cm/s for benign tumours, which were significantly different (P=0·01). For vascular endothelial growth factor, an average score of 2·22 was found for group 2 and 1·66 for group 1 (P=0·03). Positive correlations were found between vascular endothelial growth factor and presence of vascularisation (P=0·04 and r=0·3658) and between vascular endothelial growth factor and maximum velocity (P=0·03 and r=0·3913). Clinical Significance : Doppler evaluation may be used to predict malignancy of mammary tumours in bitches. 相似文献
110.
Vicente J Ruiz-Fons F Vidal D Höfle U Acevedo P Villanúa D Fernández-de-Mera IG Martín MP Gortázar C 《The Veterinary record》2005,156(13):408-412
Serum samples from 693 hunted wild boar (Sus scrofa) were analysed by means of a blocking ELISA technique, and the mean (se) prevalence of antibodies to Aujeszky's disease virus was 44 (4) per cent. All the seropositive wild boar were from south central Spain, except for one from central Spain, close to the main positive area. In this area, where large game species are increasingly managed for hunting, the seroprevalence was affected by the type of management. More intensively managed populations had a higher prevalence than wild boar living in natural situations, and the seroprevalence increased with the age of the animals; the seroprevalence was higher in females in all age groups. The seroprevalence in males more than one year old peaked after the breeding season, whereas females of the same age had a higher and constant seroprevalence throughout the year. 相似文献