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941.
报道采自福建福州、吉林长春的3种跳小蜂,即桔小食甲跳小蜂Cerchysiella citricola Xu,sp.nov.,寄主为日本方头甲Cybocephalis nipponicus Endr.-Younga,初级寄主为柑橘类;扁角尼克跳小蜂Neocladella platicornis Xu,sp.nov.寄主不明和短翅思奇跳小蜂,其触角扁平膨大;短翅思奇跳小蜂Schilleriella brevipterus Xu,sp.nov.寄主为粉蚧,其前翅退化缩短.对新种进行了详细描述.本文也是尼克跳小蜂属Neocladella Girault和思奇跳小蜂属Schilleriella Ghesquiere在我国分布的首次记录.标本保存在浙江大学农业与生物技术学院应用昆虫研究所.  相似文献   
942.
Thus far, the release of herbivore‐induced synomones (HIS) has almost exclusively been demonstrated in somatic plant tissue. Here we present evidence for the production of HIS from reproductive tissue, i.e., seeds. The study system consisted of wheat grains (Triticum aestivum L., Poaceae) infested by larvae of the granary weevil Sitophilus granarius L. (Coleoptera, Curculionidae), which in turn are attacked by the parasitic wasp Lariophagus distinguendus Förster (Hymenoptera, Pteromalidae). The use of potential chemical signals from the infested grain for host recognition of L. distinguendus was studied with weevil‐infested grains that had developed under a range of humidity conditions. Wasps always performed longer antennal drumming on infested than healthy grains, demonstrating that they were able to recognize infested grains under all humidity conditions. In grains developed at a high humidity (75% r.h.), host recognition is enabled by chemical signals arising from the host faeces which densely cover infested grains. However, in grains from a low humidity (45% r.h.) almost no faeces are present, indicating that other cues are used by the wasp. Control experiments revealed that these other cues are neither chemical signals from faeces contaminations, volatiles from faeces nor host larvae inside the grain, movement of host larvae, or moisture content of infested grains. Therefore, wasp recognition of infested grains in low humidity conditions is probably based on chemical signals from the grain itself that are induced by the feeding of granary weevil larva. Further experiments revealed that infested grains increase their viability when granary weevil larvae are killed by the idiobiont L. distinguendus. This justifies the categorisation of potential signals from the grain as HIS. To our knowledge, this is the only system where potential HIS in plant seeds have been studied. We discuss whether potential HIS are actively produced by infested grains or are a by‐product of grain metabolism.  相似文献   
943.
The color of lepidopteran eggs often varies by species or egg condition, and parasitoids that attack lepidopteran eggs could therefore potentially use color to obtain information about host identity or quality. The objective of our study was to determine whether females of the egg parasitoid Trichogramma ostriniae Pang & Chen (Hymenoptera: Trichogrammatidae) showed differential responses to egg color when searching for hosts over short distances and when evaluating the suitability of encountered eggs. We examined the wasps’ host‐selection behavior in a Petri dish arena using white, yellow, green, and black clay beads as egg models presented against a green background (to mimic leaf color). In no‐choice tests, bead color had a significant effect on the proportion of tested wasps that accepted a bead for further examination, on the time it took wasps to find and begin examining a bead, and on the time that wasps spent examining the beads. However, bead color had only a marginally significant effect on the proportion of wasps attempting to drill into a bead with their ovipositors, and no significant effect on the amount of time they spent drilling. The wasps also showed significant color preferences when given a choice between two adjacent beads of different colors. The results of the no‐choice and choice trials taken together indicated a color preference ranking of yellow > white > green > black. The wasps’ higher preference for the yellow and white egg models generally corresponds to the white or yellowish‐white egg color of T. ostriniae's target host, the European corn borer moth, Ostrinia nubilalis Hübner (Lepidoptera: Crambidae). The wasps’ strong rejection of black egg models is likely to be an adaptive response that reflects the fact that eggs that are wholly or partially black are often unsuitable for parasitization due to advanced caterpillar development, damage to the egg, or previous parasitization.  相似文献   
944.
Generalist parasitoids are well‐known to be able to cope with the high genotypic and phenotypic plasticity of plant volatiles by learning odours during their host encounters. In contrast, specialised parasitoids often respond innately to host‐specific cues. Previous studies have shown that females of the specialised egg parasitoid Chrysonotomyia ruforum Krausse (Hymenoptera: Eulophidae) are attracted to volatiles from Pinus sylvestris L. induced by the egg deposition of its host Diprion pini L. (Hymenoptera: Diprionidae), when they have previously experienced pine twigs with host eggs. In this study we investigated by olfactometer bioassays how specifically C. ruforum responded to oviposition‐induced plant volatiles. Furthermore, we studied whether parasitoids show an innate response to oviposition‐induced pine volatiles. Naïve parasitoids were not attracted to oviposition‐induced pine volatiles. The attractiveness of volatiles from pines carrying eggs was shown to be specific for the pine and herbivore species, respectively (species specificity). We also tested whether not only oviposition, but also larval feeding, induces attractive volatiles (developmental stage specificity). The feeding of D. pini larvae did not induce the emission of P. sylvestris volatiles attractive to the egg parasitoid. Our results show that a specialist egg parasitoid does not innately show a positive response to oviposition‐induced plant volatiles, but needs to learn them. Furthermore, the results show that C. ruforum as a specialist does not learn a wide range of volatiles as some generalists do, but instead learns only a very specific oviposition‐induced plant volatile pattern, i.e., a pattern induced by the most preferred host species laying eggs on the most preferred food plant.  相似文献   
945.
中国叉齿细蜂属网腰细蜂种团二新种记述(膜翅目:细蜂科)   总被引:1,自引:1,他引:0  
记录我国叉齿细蜂属Exallonyx叉齿细蜂亚属Exallonyx网腰细蜂种团dictyotus-group2新种:采自陕西和浙江的黑唇叉齿细蜂Exallonyxnigrolabius,sp.nov.和采自贵州的短脊叉齿细蜂Exallonyxbrevicarinus,sp.nov.。模式标本保存于浙江大学寄生蜂标本室。  相似文献   
946.
热茧蜂属Tropobracon Cameron是1个小型属,过去全世界已知5种。本文报道了我国发现的1个新种——黑热茧蜂T.niger,sp.nov.,并建立了该属中国已知3种的分种检索表。新种模式标本保存于福建农林大学植物保护学院益虫研究室。黑热茧蜂Tropobracon niger,新种(图1~8) 本新种与三化螟热茧蜂Tropobracon luteus Cameron,1905较接近,但前者的1)后翅1-SC+R脉宽度明显比1r-m脉窄(图1);2)头部光滑,后头强度凹入(图8);3)中胸盾片中前方无1条短沟(图6);4)体大多黑色,头部及胸部部分红褐色;5)复眼长为上颊长的1.8倍(图8),颚眼距长为上颚基宽的2.3倍(图3)等特征可与之区别。正模:♀,福建沙县洋坊,1981-Ⅺ-17,黄居昌采:副模:3♀♀,同正模。  相似文献   
947.
寄生云杉球果卷蛾的姬蜂   总被引:5,自引:5,他引:0  
报道采自青海省祁连县寄生云杉球果卷蛾Laspeyresia strobilella Linnaeus的3种姬蜂,其中1新种:祁连缺沟姬蜂Lissonota qilianica Sheng,sp.nov.,中国1新纪录:欧松梢小卷蛾曲姬蜂Scambus(Scambus)buolianae(Hartig,1838),对青海汤姬蜂Townesia qinghaiensis He,1996的雌性作了首次描记.标本保存在国家林业局森林病虫害防治总站.  相似文献   
948.
钩瓣叶蜂属隶属于叶蜂科,已知230余种,中国已经报道77种.记述中国钩瓣叶蜂属1新种:尖唇钩瓣叶蜂Macrophya acuminiclypeus sp.nov.,该种与女贞钩瓣叶蜂 M.ligustri Wei et Huang,1997近似,但唇基缺口深,侧角狭长,端部尖,头部额区和中胸侧板刻点粗密,中胸背板前叶中沟模糊,几乎消失,后足股节基部1/4黄白色,锯腹片22刃,中部锯刃具10~11个后位亚基齿等,差别明显,易于鉴别.正模♀,江西萍乡芦溪,2004-04-03,魏美才采;副模:1♀,湖南浏阳,1985-05-08,童新旺,1♀,福建武夷山,1 100 m,2004-05-20,周虎.新种模式标本保存于中南林业科技大学昆虫模式标本室.  相似文献   
949.
报道发现于我国的两个新纪录属,短颚姬蜂属Skiapus Morley,1917和棒角姬蜂属Hellwigia Gravenhorst,1823的种类:黑短颚姬蜂Skiapus niger Sheng,sp.nov.和暗棒角姬蜂Hellwigia obscura Gravenhorst,1823.编制了这2属的分种检索表.  相似文献   
950.
Glyptomorpha baetica, G. discolor, G. gracilis, G. kasparyani, and G. pectoralis are recorded from Turkey. Glyptomorhpa baetica is new to the Turkish fauna. It was reared from a new host Sesamia nonagrioides (Noctuidae, Lepidoptera) and was redescribed. Its diagnostic characters are illustrated. An identification key is provided for nine species of Glyptomorpha of Turkey and adjacent regions. Distribution of each species is added.  相似文献   
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