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1.
四川西部蝇类物候的研究   总被引:8,自引:0,他引:8  
冯炎 《生态学杂志》1996,15(6):26-35
四川西部蝇类物候的研究冯炎(四川省雅安地区卫生防疫站,625000)StudiesofPhenologyofCalytrataeFliesinWesternSichuan,China.FengYan(HygienicandAntiepidemic...  相似文献
2.
四川省雅安地区有瓣蝇类滋生场所的调查   总被引:4,自引:0,他引:4       下载免费PDF全文
冯炎  刘桂兰 《昆虫学报》1990,33(1):55-63
 本文报告对四川西部雅安地区有瓣蝇类滋生场所的调查,发现47型滋生场所中有66种有瓣蝇类滋生,其中25种的滋生场所及3种的雪下存活蛹前期个体为首次报道.文中对如何控制蝇类滋生场所的问题提出了初步建议.  相似文献
3.
Seventeen herb, shrub and tree species of commercial and ecological importance in southern Africa were exposed at one location to ultraviolet-B (UV-B, 280-315 nm) radiation approx. 35 % above clear-sky background (control). The aims were to assess how UV-B affects canopy area, dry mass, and some biochemical and morphological properties of leaves, and to investigate whether differences between species are related to growth form of the plants. There was no pattern of response to UV-B related to growth form. Leaves of trees had altered chlorophyll a and b, carotenoid and flavonoid concentrations, but those of shrubs or herbs did not. Non-structural carbohydrates were unaffected. Smaller canopy areas and dry masses were observed under enhanced UV-B, but these were not statistically different among growth forms. There was a general insensitivity of species to elevated UV-B. Only five species had significantly altered leaf biochemical and morphological properties, canopy area and dry mass, the changes differing in magnitude. There was no consistent pattern of change in leaf thickness or biochemical composition with increased UV-B. Correlation analyses did not support the view that growth is less negatively affected in species with thick leaves or in those where leaf thickness increases, or in species with naturally high leaf flavonoid contents or that are able to synthesize additional flavonoids in response to UV-B enhancement. The analyses did not support the hypothesis that growth was inhibited by starch accumulation in leaves under elevated UV-B. However, changes in leaf shape did correlate with canopy area and dry mass, showing the importance of photomorphogenetic changes caused by UV-B which affect species' performance. We conclude that generalizations on plant sensitivity to UV-B based on growth form and functional type could be misleading, and that the great majority of economically important species of the region are likely to be insensitive to future UV-B increases. Notable exceptions include the Colophospermum mopane tree ecotypes chota and leslie and the arable annual Vigna unguiculata, both of which are traditional sources of livelihood to rural African populations and of importance to African industry and agriculture.  相似文献
4.
“Myiasis-causing flies” is a generic term that includes species from numerous dipteran families, mainly Calliphoridae and Oestridae, of which blowflies, screwworm flies and botflies are among the most important. This group of flies is characterized by the ability of their larvae to develop in animal flesh. When the host is a live vertebrate, such parasitism by dipterous larvae is known as primary myiasis. Myiasis-causing flies can be classified as saprophagous (free-living species), facultative or obligate parasites. Many of these flies are of great medical and veterinary importance in Brazil because of their role as key livestock insect-pests and vectors of pathogens, in addition to being considered important legal evidence in forensic entomology. The characterization of myiasis-causing flies using molecular markers to study mtDNA (by RFLP) and nuclear DNA (by RAPD and microsatellite) has been used to identify the evolutionary mechanisms responsible for specific patterns of genetic variability. These approaches have been successfully used to analyze the population structures of the New World screwworm fly Cochliomyia hominivorax and the botfly Dermatobia hominis. In this review, various aspects of the organization, evolution and potential applications of the mitochondrial genome of myiasis-causing flies in Brazil, and the analysis of nuclear markers in genetic studies of populations, are discussed.  相似文献
5.
We report a novel feature of leaf variegation. As is often the case in tropical forest floor herbs, Schismatoglottis calyptrata leaves feature structural variegation. Examination of leaf anatomy in S. calyptrata revealed a novel feature of structural variegation, which was generated by variation in the spatial arrangement of the adaxial-most tip of the palisade cells. In fully green leaf parts, contact between the adaxial-most tip of the palisade cells and the cone-shaped base of the outer epidermis cells was tight, and palisade cells were arranged radially around each epidermal cell. In dull, grayish-green leaf parts, the contact was loose, and no particular spatial arrangement of palisade cells relative to epidermal cells was observed. This feature of structural variation could be disadvantageous for photosynthesis efficiency in view of the hypothesis that, for rainforest herbs, cone-shaped epidermal cells may function as lenses. However, the high frequency of leaf variegation of S. calyptrata in natural habits suggests that this structural variegation plays an unknown advantageous role.  相似文献
6.
The myiophilous pollination syndrome of stapeliads is investigated. Olfactory stimuli, imitating dung or decaying organic (zoogenic or phytogenic) matter, are used as attractants, together with mimetic colouration and, sometimes mimetic sculpturing. In most species nectar is present. The nectar mainly serves as optical attractant causing brilliance effects, and as visitor guide. However, nectar obviously is also a reward in many species. Flies (Cyclorrhapha:Calyptratae) constitute the most important pollinating group. In the pollination process they carry pollinaria only at the distal parts of their proboscis, never on their legs. No fundamental differences between the pollinator spectra of flowers in habitat and cultivated ones were observed.  相似文献
7.
1980~1990年,采集用网捕法,分类用昆虫学分类原理与方法,调查四川省二郎山山区有瓣蝇类种类及其相关情况.结果 显示,二郎山山区蝇类有307种,隶属8科25亚科93属.其中特有种有197种,占已知种的64.16%,发现二郎山新纪录种132种,占已知种的42.99%;区系成分分析表明,二郎山山区有瓣蝇类以东洋区成分为主.成蝇年周期中的密度高峰在5月和6月,优势种为紫兰优毛蝇、家蝇和反吐丽蝇;发现黄粪蝇、密胡邻种蝇和黑尾黑麻蝇幼虫可在大雪覆盖下的孳生地过冬.本研究对二郎山山区有瓣蝇类的区系组成和分布等相关特点有了初步了解;但二郎山为横断山脉一部分,地形地貌相当复杂,是最具生物多样性地区之一,尚需深入研究.  相似文献
8.
用网捕法对四川名山蒙顶山山区有瓣蝇类进行了调查,共采集成蝇标本18873只,隶属7科19亚科62属132种,其中古北区+东洋区种占34.8%,东洋区种占29.5%,特有种占9.8%,跨多区种占25.9%。紫翠蝇Neomyia gavisa,肥躯金蝇Chysomya pinguis及反吐丽蝇Calliphora vomitoria为该山区优势种,其构成比分别为24.4%、19.8%和11.2%;毛胫厕蝇Fanma hirtitibia等13种为当地特产种。紫翠蝇Neomyia gavisa、巨尾阿丽Aldrichina grahami、反吐丽蝇Calliphora vomiwria及紫绿蝇htcilia porphyrina常年均可见成蝇出没。  相似文献
9.
The resolution potential of internal transcribed spacer 2 (ITS2) at deeper levels remains controversial. In this study, 105 ITS2 sequences of 55 species in Calyptratae were analyzed to examine the phylogenetic utility of the spacer above the subfamily level and to further understand its evolutionary characteristics. We predicted the secondary structure of each sequence using the minimum-energy algorithm and constructed two data matrixes for phylogenetic analysis. The ITS2 regions of Calyptratae display strong A-T bias and slight variation in length. The tandem and dispersed repeats embedded in the spacers possibly resulted from replication slippage or transposition. Most foldings conformed to the four-domain model. Sequence comparison in combination with the secondary structures revealed six conserved motifs. Covariation analysis from the conserved motifs indicated that the secondary structure restrains the sequence evolution of the spacer. The deep-level phylogeny derived from the ITS2 data largely agreed with the phylogenetic hypotheses from morphologic and other molecular evidence. Our analyses suggest that the accordant resolutions generated from different analyses can be used to infer deep-level phylogenetic relations.  相似文献
10.
Based on a revision of large recent collections housed by Czech University of Life Sciences Prague, Masaryk University, Brno, and in the private collection of Yu. Verves (Kyiv, Ukraine), new distributional data and an updated and commented list of Czech and Slovak Sarcophagidae are presented. The following six species are firstly recorded from the Czech Republic: Macronychia (s. str.) substriginervis Verves & Khrokalo, 2006, Paragusia multipunctata (Rondani, 1859), Oebalia praeclusa (Pandellé, 1895), Nyctia lugubris (Macquart, 1843), Blaesoxipha dupuisi Léonide & Léonide, 1973, and B. grylloctona Loew, 1861. As a result, 143 species of the family Sarcophagidae are currently known from the Czech Republic (109 from Bohemia and 129 from Moravia), and 131 species are known from Slovakia.  相似文献
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