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161.
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苹楔天牛Saperda candida Fabricius(鞘翅目Coleoptera:天牛科Cerambycidae)原产北美,主要危害果树,300多年来被认为是原产地果园最具毁灭性的害虫。2008年该害虫首次传入欧洲(德国费马恩岛),因而受到许多国家的重视。该害虫的寄主植物苹果、梨、李、山楂等果树在我国种植非常广泛,具有十分重要的经济价值。该天牛会随着寄主植物的引进、调运进行远距离传播,我国应加强对该害虫的检疫。文章就其形态特征、危害特点、生物学特性及潜在风险作一阐述。  相似文献   
163.
The obscure mealybug Pseudococcus viburni (Signoret) (Hemiptera: Pseudococcidae) is recorded for the first time from Colombia based on specimens collected on Opuntia cylindrica (Lam.) DC., Mammillaria sp. (Cactaceae), Escallonia paniculata (Ruiz & Pav.), Roem. & Schult. (Escalloniaceae), Ficus carica L. (Moraceae), Coffea arabica L. (Rubiaceae), Citrus sp. (Rutaceae), Cestrum nocturnum L. and Solanum betaceum Cavanilles (Solanaceae). Multiple methods were used to identify P. viburni because it belongs to the “Pseudococcus maritimus” complex, a group composed of more than 60 species with high variation in morphological characteristics. The specimens were identified based on the morphology and morphometric analysis of third-instar nymphs and adult females. This morphological identification was corroborated by data on geographical distribution, plant hosts and a molecular identification using two different loci, CO1 (mtDNA) and the 28S ribosomal gene (nuclear genome). An updated list of species of Pseudococcus Westwood recorded from Colombia and information on morphological variation found in the studied specimens from Brazil and Colombia are provided.  相似文献   
164.
Tephritid fruit flies are important pests of fruits and vegetables worldwide, but few studies have examined their ecology and life history in their native range because non-adult individuals of closely related species are morphologically indistinguishable. To identify non-adult individuals collected from host plants, flies examined in earlier studies were painstakingly reared to adulthood. Using Zeugodacus scutellatus Hendel as a model species, this study established a simple DNA extraction and purification method based on loop-mediated isothermal amplification (LAMP) reaction for on-site molecular identification of non-adult fruit flies. The non-adult individual body fluids were sampled using a sterilized toothpick and then diluted in TE buffer and heated for a short time. Alternatively, eggs were crushed in TE buffer using a sterilized toothpick and then heated. After heated buffer was added to the LAMP reaction mixture as template DNA and the mixture was heated for incubation of polymerase, the LAMP reaction detected the amplified DNA of Z. scutellatus. This purification method, characterized by heating after dilution with TE buffer, is simple and rapid. Our purification method, which obviates large centrifuges, thermal cyclers, and other apparatus, provides lower-cost and better on-site molecular identification of non-adult fruit flies than methods described in earlier reports. The LAMP-based molecular identification technique and our purification method are particularly useful for studying quarantined pest organisms that cannot be removed from their native areas.  相似文献   
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Abstract   Australia is isolated from the rest of the world geographically but not scientifically: Australian entomology has a long and distinguished record of collaboration with a diversity of other countries. Much of the focus relates to keeping new pests out of Australia (biosecurity and quarantine) and managing those that do get in (biological control and insect pest management). Many projects have cooperated with neighbouring countries, to assist them to control pests and thereby reduce threats to Australia. Biological control projects have also had two-way benefits, and examples are given of various collaborations in these fields.  相似文献   
167.
Rats have been introduced to islands throughout the world. They have caused breeding failures, population declines and complete extirpation of vulnerable bird species. Such impacts can be difficult to diagnose in situations where extirpation occurred prior to the vulnerable species being recorded. Mitigating the impacts of rats on seabirds depends on quarantine measures for islands where rats are currently absent, and eradication or control campaigns on those where they are present. These measures can be challenging in terms of both costs and practicalities, and so can seldom be applied to all islands within a given region. Hence a prioritization exercise is often required to identify those islands where management would be most cost-effective. In this review we present a case study of rat management in the UK, Channel Islands and Isle of Man. We review rat management for the study area to date and present a simple scoring approach to prioritize islands for eradication campaigns, including those where the procellariiform priority species are currently absent. We recommend further research into rat management for the study area and on the applicability of this approach elsewhere in the world.  相似文献   
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