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11.
本文研究了稻田生境和非稻田生境间寄生性天敌的迁移扩散规律及其对水稻主要害虫的控制作用.结果表明,寄生蜂从大豆生境扩散到稻田生境的数量显著高于其从玉米生境扩散到稻田生境,而田埂种植玉米的寄生蜂扩散数量与不种植玉米相比无显著性差异.田埂配置大豆的有机稻田内二化螟Chilo suppressalis、三化螟Tryporyza incertulas、稻纵卷叶螟Cnaphalocrocis medinalis cnienee和褐飞虱Nilaparvata lugens的卵寄生率分别为17.8%,20.3%,10.2%和12.4%,与未配置大豆的对照相比分别增加了4.3%,7.5%,2.1%,和3.4%;它们的幼虫寄生率分别为14.7%,31.7%,21.3%,7.3%,与对照相比分别增加了5.3%,9.8%,5.7%和2.8%.而田埂配置玉米的有机稻田的二化螟,三化螟,稻纵卷叶螟和褐飞虱的卵寄生率分别为10.3%,14.4%,8.6%和9.3%;与未配置玉米的对照相比分别降低了3.2%,增加1.6%,0.5%和0.3%;它们的幼虫寄生率分别为10.3%,19.4%,17.5%和2.6%,与对照相比分别增加了0.9%,降低了2.5%,增加了1.9%和降低了1.9%.研究结果可为通过建立合理的水稻邻作模式进行害虫生物防治提供重要科学依据. 相似文献
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B. V. Agboton D. Salifu Z. Seguni M. E. Sijaona S. Shomari S. Ekesi N. K. Maniania 《Journal of Applied Entomology》2013,137(10):782-789
Cashew (Anacardium occidentale) is an economically important cash crop for many rural households in Tanzania. However, its production is constrained by some insect pests and diseases. As a prerequisite for the development of a more sustainable integrated insect pest and disease management strategy for cashew, information on the biology and ecology of the key insect pests and diseases in a changing environment, and on influencing biotic and abiotic factors, is needed. Surveys were conducted in the major cashew nut‐producing areas of Tanzania for two seasons: August to December, 2009, and August to December, 2010. Data on number of infested and infected shoots by key insect pests and diseases, natural enemies and associated farmer practices, namely synthetic pesticide use and intercropping systems, were collected from different subzones within agroecological zones. Our data showed that abundance and diversity of key cashew insect pests and diseases were influenced by agroecological zones and subzones. Intercropping was more commonly practised in the northern than in the southern zone. Agrochemicals were most frequently used in the southern agroecological zone and affected the occurrence of natural enemies, notably the weaver ant that was more abundant in the northern zone. Furthermore, our findings revealed that Helopeltis sp. and the powdery mildew remained the major constraints to cashew nut production in Tanzania. 相似文献
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Qing Feng Takeshi Kumagai Yasuyoshi Torii Yoshimasa Nakamura Toshihiko Osawa Koji Uchida 《Free radical research》2013,47(6):779-788
Oxidative stress has been implicated in the pathogenesis of numerous diseases, including cancer. In the present study, the protective effect of natural antioxidants, such as quercetin and tea polyphenols, on intracellular oxidative stress was studied. Here we report a novel function of quercetin and tea polyphenols, as potential inhibitors of 4-hydroxy-2-nonenal (HNE)-induced intracellular oxidative stress and cytotoxicity. In rat liver epithelial RL34 cells, a potent electrophile HNE dramatically induced the productions of reactive oxygen species (ROS), which correlated well with the reduction in cell viability. We found that quercetin and tea polyphenols, such as epigallocatechin gallate and theaflavins and their gallate esters, significantly inhibited the HNE-induced ROS production and cytotoxicity. In addition, HNE induced a transient decrease in the mitochondrial membrane potential (Δψ), which was also retarded by the antioxidants. These data suggest that the antioxidants, such as quercetin and tea polyphenols, are inhibitors against mitochondrial ROS production. 相似文献
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Magaly Fonseca-Medrano Alexandre Specht Fernando Antônio Macena Silva Pollyanna Nunes Otanásio Juaci Vitória Malaquias 《Revista Brasileira de Entomologia》2019,63(4):308-315
The owlet moths (Lepidoptera: Noctuidae) Anicla infecta (Ochsenheimer 1816), Elaphria agrotina (Guenée 1852) and Spodoptera frugiperda (J.E. Smith 1797) occur in the entire American continent. These polyphagous moths have a preference for grasses, and have different biological habits. In this study, the populations of these three species were evaluated monthly with light traps in the Brazilian Savannah, ranging a span of four crop seasons (from July, 2013 to June, 2017). The population data were analyzed and correlated with the meteorological variables: maximum temperature, minimum temperature, relative humidity and precipitation. A total of 4719 individuals were collected in the following percentages: A. infecta (n = 459; 9.73%), E. agrotina (n = 1809; 38.33%) and S. frugiperda (n = 2451; (51.94%). The abundance of all species went down from the first crop season (2013/2014) to the third (2015/2016). In the fourth crop season (2016/2017), the populations of A. infecta and E. agrotina stabilized, but the abundance of S. frugiperda experienced further decrease. The numbers of individuals of three species declined when precipitation was much above (crop season 2014/2015) and below (crop season 2015/2016) than expected by the climatological normal. There were significant, but different degrees of correlation, between the meteorological factors and the ONI index (Oceanic Niño Index - indicator for monitoring El Niño-Southern Oscillation or “ENSO”) with respect to monthly population variations. The results are discussed in accordance with principles of the Integrated Pest Management (IPM) in mind, given the continental distribution and agricultural importance of the three owlet moth species studied. 相似文献
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Akiko Satake Takayuki Ohgushi Satoru Urano Koichiro Uchimura 《Ecological Research》2006,21(1):107-116
The tea leaf roller, Caloptilia theivora Walsingham (Lepidoptera: Gracillariinae), is one of the serious pests of tea plants in Japan. To understand the mechanism of seasonal occurrence of this insect pest, we developed a population dynamics model that explicitly incorporates the temperature-dependent development of the pest. The model predictions were compared with observed captures in pheromone traps at the experimental site of the Kagoshima Tea Experiment Research Station in Japan. The results showed that the emergence timing of the insect pest observed in the field was determined primarily by temperature. The relationship between the timing of adult emergence and the leaf damage level was also studied using a logistic regression model. The infestation level decreased as the interval between the adult peak emergence date and the date of tea plucking increased, implying that asynchrony between plant phenology and emergence of the insect pest is a critical factor reducing damage level. We examined how the damage level changes according to global warming. Increased temperature made the timing of insect appearance forward and enhance asynchrony of plant–pest phenology. Therefore, reduction of damage level by the insect pest is expected under global warming. 相似文献
19.
Despite its value as a crop and potential utility as an experimental system, relatively little is known about the molecular-genetic aspects of inheritance or physiology in the cultivated strawberry (Fragaria xananassa). This lack of information exists at a time when biotechnology may offer important remedies to address traditional and contemporary challenges that growers face. An improved understanding of genome structure will hasten the development of molecular markers and unveil clues to the composition of this unique, octoploid genome. Definition of gene function will guide the generation of transgenic resources for research use and possibly toward cultivar development. This review seeks to compile and present the current knowledge state of the molecular-genetic basis of cultivated strawberry genomic form and function. Ongoing studies promise to expand the use of genomic tools and appropriate model systems to rapidly discern the structural and functional basis for traits of interest to agriculture, such as those associated with disease, ripening, and volatile production. Together these studies bring new molecular tools to dissect complex traits, implement marker-assisted selection and address important physiological questions in the cultivated strawberry, the Fragaria genus, and the Rosaceae family. 相似文献
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低农药残留量的乌龙茶种质资源筛选研究 总被引:2,自引:0,他引:2
以福建省武夷山茶叶科学研究所鸟龙茶种质资源圃120份资源为试验材料,依外部形态特征初步筛选出31份比较有希望的品种(系)。将联苯菊酯、甲氰菊酯、氯氰菊酯和噻嗪酮4种农药喷施于这31份资源,7d后采摘鲜叶,烘干固样。用气相色谱法分析检测31份品种(系)鲜叶中4种农药的残留量,筛选出低联苯菊酯、低甲氰菊酯、低氯氰菊酯和低噻嗪酮残留量的乌龙茶特异资源各5、4、3和7份。 相似文献