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31.
32.
目前,随着人们质量意识的逐渐提高,急需建立一套植物认证体系来证明种植者已经遵守了某种标准,并且在这个标准下种植者生产的产品质量能够达到已制定的目标。今年5月,在巴西莫卡花卉市场(Mercaflora Markrt)举办的第十届花卉论坛上,官方正式启动了这一植物认证体系,巴西南部的圣卡塔林纳州成为这项国家计划的试点。圣卡塔林纳是一个传统的生产景观植物的地区,历来以创新闻名。巴西的花卉研究所也建于该地。该项植物认证的实施方式有两种,一种是由联合机构规定产业标准和产品质量;另一种是根据农业部的相关规定,政府授权认证机构。其中认证… 相似文献
33.
20世纪50年代,移民去巴西的大批荷兰人开创了观赏植物生产.1959年,荷兰移民柯拉斯·斯马克(Klaas Scho enmake r)开始在如今已是剑兰主产区的奥朗布拉(Holambra)种植他从荷兰带来的剑兰球根,这一做法在当时遭到很多人的怀疑,包括当时的奥朗布拉的领导.在那时,人们认为要谋生只能靠农作物. 相似文献
34.
Traditional Mexican Agricultural Systems and the Potential Impacts of Transgenic Varieties on Maize Diversity 总被引:1,自引:1,他引:1
The discovery of transgenes in maize landraces in Mexico, a center of diversity for this crop, raises questions about the
potential impact of transgene diffusion on maize diversity. The concept of diversity and farmers’ role in maintaining diversity
is quite complex. Farmers’ behavior is expected to have a significant influence on causing transgenes to diffuse, to be expressed
differently, and to accumulate within landraces. Farmers’ or consumers’ perceptions that transgenes are “contaminants” and
that landraces containing transgenes are “contaminated” could cause these landraces to be rejected and trigger a direct loss
of diversity.
Mauricio R. Bellon is a human ecologist working in the Economics Program of the International Maize and Wheat Improvement Center (CIMMYT) in
Texcoco, Mexico. He received his MSc and PhD in ecology at the University of California, Davis. His current research includes
projects that deal with on-farm conservation of maize, gene flow in traditional farming systems, and the impact of improved
germplasm in the livelihoods of poor farmers.
Julien Berthaud is a population geneticist working for the Institut de Recherche pour le Développement (IRD). He received his PhD in plant
science at the University of Paris 11. His current research includes projects related with the dynamics of genetic diversity,
especially in traditional maize farming systems. 相似文献
35.
36.
Multiple effects of urbanization on the biodiversity of developing countries: The case of a fast-growing metropolitan area (Concepción, Chile) 总被引:1,自引:0,他引:1
Urbanization is increasingly homogenizing the biota of less developed countries. Even though urban sprawl is a worldwide problem, most studies on the effects of urbanization, and the conceptual models have focused on developed countries. South America has not escaped urbanization, and here we discuss the potential impacts of urban sprawl with respect to three ecosystems in the metropolitan area of Concepción, Chile. We consider this area a good model and fairly representative of other cities in developing countries which are also experiencing rapid and uncontrolled growth. We found that the impacts of urban sprawl on biodiversity in the metropolitan area of Concepción differ little from cities in other parts of the world: native ecosystems are replaced by pavements and buildings and what is left of the natural soil is covered with green areas dominated by non-native ornamental species. Wetlands and other peri-urban ecosystems are rapidly being destroyed, fragmented or invaded by non-native species. We found that from a study area of 32,000 ha, there was a net loss to urbanization of 1734 ha of wetlands (23% of the original) and 1417 ha (9%) of agricultural, forest and shrub land cover types between 1975 and 2000. From the total area urbanized (3151 ha), 55% corresponded to wetlands and 45% to agricultural, forest and shrub lands cover types. We see the lack of environmental awareness as a major cause of the increasing deterioration of biodiversity in urban areas of developing countries. More research is needed to fully understand the effects of urban sprawl on the biodiversity of developing countries to include these ecosystems in global conservation strategies. 相似文献
37.
Participatory landrace selection for on-farm conservation: An example from the Central Valleys of Oaxaca, Mexico 总被引:8,自引:1,他引:8
Mauricio R. Bellon Julien Berthaud Melinda Smale José Alfonso Aguirre Suketoshi Taba Flavio Aragón Jaime Díaz Humberto Castro 《Genetic Resources and Crop Evolution》2003,50(4):401-416
On-farm conservation is recognized as a key component of a comprehensive strategy to conserve crop genetic resources. A fundamental problem faced by any on-farm conservation project is the identification of crop populations on which efforts should be focused. This paper describes a method to identify a subset of landraces for further conservation efforts from a larger collection representing the diversity found in the Central Valleys of Oaxaca, Mexico. Mexico is a center of origin and diversity for maize (Zea mays L.). The 17 landraces selected from an initial collection of 152 satisfy two criteria. First, they represent the diversity present in the larger collection. Second, they appear to serve the interests of farmers in the region. Data for applying the method were elicited through participatory as well as conventional techniques. They incorporate the complementary perspectives of both men and women members of farm households, and of plant breeders and social scientists. 相似文献
38.
Patricio Arce Mauricio Moreno Mónica Gutierrez Marlene Gebauer Paola Dell’Orto Hebert Torres Ivette Acuña Pauline Oliger Alejandro Venegas Xavier Jordana Julio Kalazich Loreto Holuigue 《American Journal of Potato Research》1999,76(3):169-177
Blackleg and soft rot diseases, caused by the bacteriumErwinia carotovora, are among the diseases that cause important losses in culture and storage of potato. In this paper, we introduced bacterial resistance into potato, via genes encoding for proteins with antibacterial activity. For this purpose, potato clones were transformed either with the gene encoding the acidic attacin protein fromHyalophora cecropia, or with the gene encoding the cecropin analog peptide SB37. These clones were evaluated for soft rot and blackleg resistance, after inoculation with the bacterial strainErwinia carotovora subsp.atroseptica T7. Results reported in this paper indicate that a considerable percentage of the potato clones (15–22%) showed increased resistance to bacterial infection, revealed by reduced severity of blackleg or soft rot symptoms. Expression of the transgenes was demonstrated in some of the clones by Northern blot analysis. This is the first report indicating that expression of the gene encoding for an attacin protein and for the cecropin SB-37 peptide in transgenic potato confers increased resistance to bacterial infection. 相似文献
39.
ULTRASONOGRAPHY OF THE CANINE, FELINE AND EQUINE TONGUE: NORMAL FINDINGS AND CASE HISTORY REPORTS 总被引:3,自引:0,他引:3
Mauricio Solano Med. Vet. Dominique G. Penninck DVM 《Veterinary radiology & ultrasound》1996,37(3):206-213
A submental approach using a 5, 7.5 and 10 MHz mechanical sectorial transducers was used to evaluate the ultrasonographic appearance of the normal and abnormal canine, feline and equine tongue. Seven normal animals were used to characterize the in vivo normal ultrasonographic appearance of the oropharynx. Consistently seen anatomical landmarks included the lingual parenchyma, lingual artery, soft and hard palate interfaces, mandible, basihyoid bone and sublingual musculature. Seven fresh canine, feline and equine cadavers were dissected to confirm the ultrasonographic findings. Seven animals with signs of ptyalism, dysphagia, halitosis and visible lingual lesions were also studied. A foreign body and abscesses secondary to a penetrating wound were detected in a horse. Ultrasound guidance aided surgical dissection, removal of the foreign body and intraoperative drainage of the abscesses. Ultrasound provided valuable non-invasive documentation of the architecture, size and margins of six lingual neoplasms. Ultrasonographic monitoring of the response to the treatment of lingual lesions may be beneficial in the management of patients. 相似文献
40.
Michel Almaguer Teresa Irene Rojas Francisco Javier Rodríguez-Rajo María Jesús Aira 《European journal of plant pathology / European Foundation for Plant Pathology》2012,133(2):473-482
This study characterised the airborne mycobiota of a rice plantation in Bauta (Havana, Cuba), with a view to improving crop
quality. Culturable airborne fungi were sampled between March 2007 and February 2008 using a volumetric method (SAS Super
100) with potato dextrose agar as culture medium. The total fungal count was 51,425 cfu/m3. The 39 filamentous genera identified included several major rice pathogens (Bipolaris, Curvularia, Alternaria, Pyricularia, Cercospora and Fusarium) as well as potentially mycotoxigenic species of Fusarium, Penicillium and Aspergillus. Analysis of the influence of weather-related factors on spore counts revealed that total counts and Penicillium counts correlated positively with daily relative humidity, mean temperature and dew point. 相似文献