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61.
Following the obligatory implementation of integrated pest management in the European Union (EU), the plant protection means suitable for application in organic agriculture attracted the attention of quite a wide group of potential users. In spite of the common rules of organic production, as well as the uniform principles of placing plant protection products on the market, the availability of products that can be legally used in organic crop protection differs significantly among the Member States. There is a uniform list of 10 basic substances that can be used in the protection of organic crops throughout the entire EU. Twelve Member States have official registers of plant protection products for use in organic agriculture, and the total number of qualified products per country varies from 11 in Lithuania to 576 in Italy. Some products that improve plant vigour or resistance and may be of use in protection of organic crops are placed on the market as biostimulants. They fall under the law that governs fertilisers and the systems of their registration vary widely among the Member States. In addition, there exist a number of products that have been legally introduced onto the markets of some Member States without registration as a consequence of a loophole in the law. The use of unregistered products in organic agriculture raises some doubts, but currently it seems that there is no legal basis on which to explicitly prohibit the practice. © 2017 Society of Chemical Industry  相似文献   
62.
保护地常用农药对蜡蚧轮枝菌菌丝生长影响研究   总被引:4,自引:1,他引:4       下载免费PDF全文
6种杀虫剂和 6种杀菌剂对昆虫病原真菌蜡蚧轮枝菌菌丝生长影响的研究结果表明 ,杀虫剂对蜡蚧轮枝菌菌丝生长有程度不同的抑制作用。在田间常规使用浓度下 ,5种杀虫剂对菌丝生长的抑制率在 10 %以上 ,最高者为甲氰菊酯达 17.6%。田间常规使用浓度稀释 10倍下 ,杀虫剂万灵、快灭净和锐劲特对菌丝生长抑制率低于 5% ,锐劲特在3.3~33.3mg/L时 ,菌丝生长与对照无显著差异 ,表现出与蜡蚧轮枝菌有极好的相容性 ,是菌药混用较好的候选杀虫剂。杀菌剂对蜡蚧轮枝菌菌丝生长有强烈的抑制作用 ,浓度愈高 ,抑制程度愈强。因此 ,在利用蜡蚧轮枝菌防治保护地蔬菜害虫时 ,须与杀菌剂使用保持一定的间隔期  相似文献   
63.
Several strains of Drosophila melanogaster possess mutant alleles in nicotinic acetylcholine receptor (nAChR) subunits, Dα1 and Dβ2 that confer resistance to neonicotinoids such as imidacloprid and nitenpyram, and Dα6, that confers resistance to spinosyns. These mutant strains were bioassayed with a selected set of nAChR active insecticides including neonicotinoids, spinosad, and sulfoxaflor, a new sulfoximine insecticide. All of the neonicotinoids examined, except dinotefuran showed reduced insecticidal efficacy on larvae of the Dα1 mutant, suggesting that this subunit may be important in the action of these insecticides. All of the neonicotinoids, including dinotefuran, showed reduced insecticidal efficacy on larvae possessing the Dβ2 mutation. A similar pattern of broad neonicotinoid resistance to that of Dβ2 alone was also observed for larvae with both the mutations (Dα1 + Dβ2). The Dβ2 mutation exhibited a lower level of cross-resistance to sulfoxaflor (<3-fold) than to any of the neonicotinoids (>13-fold). In contrast, there was no cross-resistance for any of the neonicotinoids or sulfoxaflor in adult flies with the Dα6 mutation, which confers high levels of resistance to spinosad. Thus in the D. melanogaster strains studied, target site resistance observed for the neonicotinoids and the spinosyns does not translate directly to resistance towards sulfoxaflor.  相似文献   
64.
Compulsory integrated pest management poses a number of challenges and issues for debate. Some of are discussed with reference to European Union requirements set out in Annex III of Directive 128/2009. Requirements on the use of plant protection products bring with them problems with dose reduction in the light of a resistance prevention strategy, the lack of threshold levels, the necessity of chemical treatments and the limited availability of effective products of biological origin. Use of preventive measures of pest control faces barriers related to profitability and a lack of knowledge on the part of farmers. Challenges to control the system, as well as the fact that some legally enforced rules are not suitable for all crops, seem also to be an issue. © 2019 Society of Chemical Industry  相似文献   
65.
利用机油乳剂对果树进行安全性和防治荔枝蒂蛀虫Conopomorpha sinensis Bradley研究试验,结果表明,喷施机油乳剂后荔枝和龙眼的落果率与对照树4无差异,喷清水的对照树其蒂蛀虫蛀果率比喷机油乳剂的处理树高,分别为150、200和250倍机油乳剂处理的2.8、3.0和2.7倍。在荔枝、龙眼园应用机油乳剂防治害虫不会导致落叶、落果、畸形叶和畸形果,也不会延缓果实的生长和成熟及降低单果重,而有利于控制介壳虫、螨类、蛀果类等害虫。机油乳剂可替代广谱性化学农药的使用,减少化学农药的污染,有利于果园天敌的生存、繁殖,提高生物多样性,改善果园生态环境。  相似文献   
66.
哈茨木霉对水稻恶苗病菌的拮抗作用   总被引:11,自引:0,他引:11       下载免费PDF全文
PDA平板拮抗试验表明 ,哈茨木霉对水稻恶苗病菌有强烈的拮抗作用 ,其孢子悬浮液的含孢量为 106~107个 /mL时 ,对恶苗病菌的抑制力达 92.33%。通过哈茨木霉菌液和 3种药剂对水稻恶苗病菌抑制效果的比较 ,哈茨木霉孢子悬浮液含孢量为 107个 /mL与施保克质量浓度 1μg/mL的抑菌效果接近 ,分别为 76.7%、75.4%。显微摄影结果显示 ,哈茨木霉以附着胞附着在恶苗病菌菌丝上 ,然后穿透菌丝在其内生长 ,或与恶苗病菌的菌丝平行生长 ,然后再侵入病菌内寄生。  相似文献   
67.
基于Web Service技术,结合个人数字助理(personal digital assistant,PDA)的使用,开发了城市绿地有害生物实时监控系统,从而解决城市绿地有害生物预警监测中信息交流不畅和共享困难的问题.调查人员手持PDA进行实地信息采集,通过无线网络即时传输;系统管理平台实时接收调查结果,经分析处理后进行信息发布.该系统应用于上海世博园区绿化植物有害生物实时监控,共收集有害生物信息153次,发布预警信息16期.结果表明,基于Web Service的城市绿地有害生物PDA实时监控系统能即时获取并发布信息,实现对有害生物的实时化、信息化监控.  相似文献   
68.
Abstract

Leaf-cutting ants (LCA) are considered one of the main herbivores and one of the most destructive pest insects of the Neotropics. Northeastern Argentina harbors the greatest species richness of these ants and in turn comprises the highest surface with forest plantations. Our aim was to establish which species of leaf-cutting ants are most commonly associated with forest plantations by analyzing their geographic distribution using published and unpublished species occurrence data. Also, estimate their potential areas of distribution along a latitudinal gradient that entirely encompasses northeastern Argentina using Ecological Niche Modeling. Only seven of the 20 species recorded were strongly associated with productive systems along the gradient, but only 2–3 species in each region could be considered high-risk species for forest plantations. High-risk species composition shows a turnover between regions. Our models show the potential distribution areas where LCA could become more abundant and dominant, and possibly causing a detrimental effect on the forest plantations in the studied region. We find that ecological niche models are useful tools to assess the environmental suitability of important LCA.  相似文献   
69.
生物多样性在害虫控制中的生态功能与机理   总被引:12,自引:1,他引:12  
生态学的有害生物治(EBPM)或生态管理(EPM)是新世纪农业有害生物防治的新对策。应用系统工程的原理和方法改变农田生态系统生物多样性,进行害虫生态控制将越来越受到人们的重视。通过农田生态系统生物多样性、调节农田生态系统多样性对天敌和害虫的影响以及生物多样性控制害虫的机制及生物多样性在害虫生态控制中的利用前景4个方面,论述农田生态系统生物多样性在害虫控制中的生态功能与机理。  相似文献   
70.
马铃薯甲虫(Leptinotarsa decemlineata (Say))是马铃薯的一种毁灭性害虫,扩散迅速,防控困难,已被许多国家列为检疫对象。云南是我国马铃薯的主要产区,目前云南省马铃薯种植区尚未发现该虫的发生与危害。为探明马铃薯甲虫在云南省的风险性,本文依据国际有害生物风险分析原则,以云南省的气候、马铃薯种植情况及马铃薯甲虫的生物学特性为基础,利用外来入侵有害生物多指标综合评价体系,对马铃薯甲虫入侵云南的风险性进行了分析。结果表明,马铃薯甲虫入侵云南的风险值为2.24,属于高度风险类型。同时,根据马铃薯甲虫较高的入侵云南的潜在风险,本文还提出了对马铃薯甲虫入侵风险管理的对策。  相似文献   
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