Micro-managing arthropod invasions: eradication and control of invasive arthropods with microbes

Non-indigenous arthropods are increasingly being introduced into new areas worldwide and occasionally they cause considerable ecological and economic harm. Many invasive arthropods particularly pose problems to areas of human habitation and native ecosystems. In these cases, the use of environmentally benign materials, such as host-specific entomopathogens, can be more desirable than broader spectrum control tactics that tend to cause greater non-target effects. The majority of successful eradication programs using arthropod pathogens have targeted invasive Lepidoptera with Bacillus thuringiensis kurstaki (Btk), such as eradication efforts against the gypsy moth, Lymantria dispar (L.), in North America and New Zealand. Both Btk and Lymantria dispar nucleopolyhedrovirus have been successfully used in efforts to limit the spread of L. dispar in the United States. For invasive arthropod species that are well established, suppression programs have successfully used arthropod-pathogenic viruses, bacteria, fungi and nematodes for either short- or long-term management. We will summarize the use of pathogens and nematodes in invasive arthropod management programs within a general context, and compare the use of microbes in gypsy moth management with diverse microbes being developed for use against other invasive arthropods.     

The role of global trade and transport network topology in the human‐mediated dispersal of alien species

More people and goods are moving further and more frequently via many different trade and transport networks under current trends of globalisation. These networks can play a major role in the unintended introduction of exotic species to new locations. With the continuing rise in global trade, more research attention is being focused on the role of networks in the spread of invasive species. This represents an emerging field of research in invasion science and the substantial knowledge being generated within other disciplines can provide ecologists with new tools with which to study invasions. For the first time, we synthesise studies from several perspectives, approaches and disciplines to derive the fundamental characteristics of network topology determining the likelihood of spread of organisms via trade and transport networks. These characteristics can be used to identify critical points of vulnerability within these networks and enable the development of more effective strategies to prevent invasions.     

The diversity of arthropods in homes across the United States as determined by environmental DNA analyses

We spend most of our lives inside homes, surrounded by arthropods that impact our property as pests and our health as disease vectors and producers of sensitizing allergens. Despite their relevance to human health and well‐being, we know relatively little about the arthropods that exist in our homes and the factors structuring their diversity. As previous work has been limited in scale by the costs and time associated with collecting arthropods and the subsequent morphological identification, we used a DNA‐based method for investigating the arthropod diversity in homes via high‐throughput marker gene sequencing of home dust. Settled dust samples were collected by citizen scientists from both inside and outside more than 700 homes across the United States, yielding the first continental‐scale estimates of arthropod diversity associated with our residences. We were able to document food webs and previously unknown geographic distributions of diverse arthropods – from allergen producers to invasive species and nuisance pests. Home characteristics, including the presence of basements, home occupants and surrounding land use, were more useful than climate parameters in predicting arthropod diversity in homes. These noninvasive, scalable tools and resultant findings not only provide the first continental‐scale maps of household arthropod diversity, but our analyses also provide valuable baseline information on arthropod allergen exposures and the distributions of invasive pests inside homes.     

Plague in China. Threat of transmission to regions of Siberia and Far East

In China plague has been officially registered from 1754 (638 epidemics with total number of cases 2.5 millions and case-fatality rate 87.5%). Endemic areas started to form on the south of the country and then the disease gradually spread on seaside provinces, where to the end of the 19th century, due to reach of island territories and large international seaports, was characterized by pandemic spread. Epidemic manifestations of plague in China were observed during more than 200 years in 23 out of 36 administrative areas affecting continental and North-Eastern regions of the country, which are immediately adjacent to border of Russia. Pneumonic plague in Manchuria clearly demonstrated the role of transport communications in transmission of this deadly infection and possibility of its spread on border regions of Siberia and Far East. Lengthy country's border, intensive migration flows, large-scale international integration, developing of near-border trade, simplification of policy for transboundary traveling are the reasons for differentiated number of sanitary protective measures on administrative borders of Siberia and Far East.     

Biochemical and evolutionary aspects of arthropod predation on ferns

Summary The widely held assumption that very few arthropods feed on ferns was questioned following field observations of arthropod damage on ferns in the state of Veracruz, Mexico. The extent and type of damage was recorded and it was found that in a measured locality, ferns were no less attacked than the angiospermous flora. As chemistry and arthropod host relationships have been shown to be so closely intertwined, plants collected in the field were analysed for both condensed tannins and cyanogenic glycosides, compounds known to be effective deterrents in temperate climates. Although all ferns tested contained tannins these did not appear to inhibit predation. Cyanogenic glycosides were present in only 3% of the fern species analysed, and it is, therefore, unlikely that they play a significant role as defensive compounds in the ferns examined.A literature search revealed a large number of ferns cited as being arthropod hosts. Approximately 420 named species of arthropods have been recorded, the majority of which are from the orders Coleoptera, Hymenoptera, Lepidoptera, and Hemiptera. Both evolutionary primitive (sawflies) and advanced (moths) arthropods are reported to be present on ferns suggesting possible coevolution of arthropods and ferns both before and after the radiation of angiosperms.     

Arthropods of a semi-natural grassland in an urban environment: the John F. Kennedy International Airport,New York

Semi-natural grassland habitat fragments, such as those found on airports, might be important for arthropod conservation and biodiversity in urban ecosystems. The objectives of this study were to: (1) describe the arthropod communities present within the grasslands on the John F. Kennedy International Airport and (2) assess spatial and temporal variation in those arthropod communities. We collected arthropods using a vacuum sampler during 2003 and using sweep-net collection methods during 2003 and 2004. During 2003, a total of 1,467 arthropods, representing 17 orders and 68 families were found in vacuum samples. A total of 3,784 arthropods, representing 12 orders and 94 families were collected in sweep-net samples during 2003. In 2004, a total of 3,281 arthropods, representing 12 orders and 85 families were collected in sweep-net samples. Hemiptera, Orthoptera, and Diptera were the most abundant taxa, accounting for 47, 18, and 14% of all arthropods captured, respectively. We found evidence of spatial and temporal variation in arthropod abundance, in particular as noted by fluctuations in Orthoptera: Acrididae and Hemiptera: Auchenorrhyncha. Hemipteran family diversity was also influenced by habitat type. Grassland habitats on airfields, although influenced by anthropogenic factors (e.g., mowing), have the potential to provide abundant and diverse arthropod communities and might serve as a refugium for such species within urban ecosystems.     

Acquisition of Cry1Ac Protein by Non-Target Arthropods in Bt Soybean Fields

Soybean tissue and arthropods were collected in Bt soybean fields in China at different times during the growing season to investigate the exposure of arthropods to the plant-produced Cry1Ac toxin and the transmission of the toxin within the food web. Samples from 52 arthropod species/taxa belonging to 42 families in 10 orders were analysed for their Cry1Ac content using enzyme-linked immunosorbent assay (ELISA). Among the 22 species/taxa for which three samples were analysed, toxin concentration was highest in the grasshopper Atractomorpha sinensis and represented about 50% of the concentration in soybean leaves. Other species/taxa did not contain detectable toxin or contained a concentration that was between 1 and 10% of that detected in leaves. These Cry1Ac-positive arthropods included a number of mesophyll-feeding Hemiptera, a cicadellid, a curculionid beetle and, among the predators, a thomisid spider and an unidentified predatory bug belonging to the Anthocoridae. Within an arthropod species/taxon, the Cry1Ac content sometimes varied between life stages (nymphs/larvae vs. adults) and sampling dates (before, during, and after flowering). Our study is the first to provide information on Cry1Ac-expression levels in soybean plants and Cry1Ac concentrations in non-target arthropods in Chinese soybean fields. The data will be useful for assessing the risk of non-target arthropod exposure to Cry1Ac in soybean.     

Game and cattle trampling, and impacts of human dwellings on arthropods at a game park boundary

Seven grassland sites were sampled at South Africa's Hluhluwe-Umfolozi Game Park boundary with the surrounding land, to assess changes in arthropod diversity in response to land use. Epigaeic arthropods were sampled using pitfall traps and a sweep net. In all, 262 morphospecies were collected, but this is an underestimate of total local species richness. Fifty percent of the species caught were single occurrences. The number of species, families and orders represented at each of the seven sites was not significantly different, but the number of individuals was significantly different. Between-site comparisons, using multivariate statistics, did not reveal any strong site groupings, with all sites being unique. The conclusion is that the reserve boundary does not significantly divide arthropod diversity on a simple inside-versus-outside basis. A major factor influencing the arthropod assemblages was intensity of land use. Indigenous game animals and domestic cattle had the same effect, and it was the intensity of trampling that was important rather than the type of trampling. Human settlements had a major impoverishing effect. The Coleoptera families, Cicindelidae, Staphylindae and Carabidae, were particularly sensitive indicator taxa of land use Scarabaeidae species were the only group that were severely affected by the fence boundary, simply because their food source, the faeces of large native mammals, was inside, leaving them without resources outside the reserve.     

黄顶菊凋落物分解对节肢动物群落结构的影响

选择黄顶菊(Flaveria bidentis)入侵的林地、农田、荒地、沟渠等4种生境作为调查样地, 比较黄顶菊与本地植物凋落物的分解速率及凋落物分解对节肢动物群落结构的影响。于2014年10月凋落物高峰期在各样地内分别搜集黄顶菊与本地植物的凋落物, 每种凋落物称取20 g装入尼龙网分解袋中, 放入各生境。2015年的每个月将不同生境不同处理凋落袋各取回10袋, 用Tullgren法分离节肢动物。 4种生境共捕获17,466头, 隶属8纲18目, 4种生境的优势类群皆为蜱螨目和啮目。其中, 林地、农田、荒地、沟渠4种生境处理组中节肢动物数量分别为1,698头, 1,838头, 2,631头, 3,413头, 分别比对照组高18%, 53%, 22%, 11%。多数月份黄顶菊凋落物中的节肢动物丰富度及多样性指数高于同生境对照组, 并且在黄顶菊生长盛期差异显著; 黄顶菊凋落物的分解速率高于对照植物分解速率, 且各月份凋落物分解速率动态与节肢动物数量变化动态呈显著相关。黄顶菊凋落物对节肢动物的影响与人为干扰程度有关, 这种影响在人为干扰较小的荒地与沟渠生境中更为明显。综上所述, 黄顶菊凋落物的分解改变了节肢动物群落结构, 并引起节肢动物多样性的升高。     

A conceptual framework for understanding arthropod predator and parasitoid invasions

Arthropods make up the largest group of invasive alien species (IAS) worldwide. Although invasion research has been biased towards alien plants and vertebrates, it has suggested potential mechanisms for the success of IAS and provided a theoretical framework for further investigation. Here we address key concepts from invasion biology that are essential to our understanding of the success of invasive alien arthropod predators and parasitoids including human intervention, environmental characteristics, propagule pressure, biological traits, and biological interactions. To gain a greater understanding of the factors most likely to influence the different stages of invasion (arrival, establishment, and spread) for alien arthropod predators and parasitoids, we use a comparative approach to compare and contrast the differential success of invasions by alien phytophagous and carnivorous arthropods. Insights gained from this comparison suggest that future research will require a multitrophic approach in order to enhance our understanding of invasions at higher trophic levels.     

板蓝根田节肢动物群落的结构与多样性研究

为了解河南省板蓝根田节肢动物群落的结构组成及物种多样性,该研究采用5点随机取样,通过网捕法和目测法调查并记录了板蓝根植株及地面上的节肢动物种类和数量。结果表明:河南省板蓝根田节肢动物群落物种丰富,共采集到2 613头,隶属于2纲10目39科61种。其中,植食性种类和捕食性种类均为24种(各占39.34%),寄生性种类4种(占6.56%),中性种类9种(占14.75%)。蜘蛛的种类占群落总种数的比例最高(为21.31%),表明田间的蜘蛛种类最丰富。鳞翅目物种的个体数量远大于其他的目,占群落个体数的43.78%。菜青虫和小菜蛾的相对丰盛度最高,分别为0.184 8和0.162 6,说明二者是河南省板蓝根田的优势害虫。捕食性集团的均匀度指数最高,寄生性集团的优势度指数最高,其中小菜蛾幼虫的寄生性天敌菜蛾盘绒茧蜂的数量最大。     

Environmental DNA metabarcoding of wild flowers reveals diverse communities of terrestrial arthropods

Terrestrial arthropods comprise the most species‐rich communities on Earth, and grassland flowers provide resources for hundreds of thousands of arthropod species. Diverse grassland ecosystems worldwide are threatened by various types of environmental change, which has led to decline in arthropod diversity. At the same time, monitoring grassland arthropod diversity is time‐consuming and strictly dependent on declining taxonomic expertise. Environmental DNA (eDNA) metabarcoding of complex samples has demonstrated that information on species compositions can be efficiently and non‐invasively obtained. Here, we test the potential of wild flowers as a novel source of arthropod eDNA. We performed eDNA metabarcoding of flowers from several different plant species using two sets of generic primers, targeting the mitochondrial genes 16S rRNA and COI. Our results show that terrestrial arthropod species leave traces of DNA on the flowers that they interact with. We obtained eDNA from at least 135 arthropod species in 67 families and 14 orders, together representing diverse ecological groups including pollinators, parasitoids, gall inducers, predators, and phytophagous species. Arthropod communities clustered together according to plant species. Our data also indicate that this experiment was not exhaustive, and that an even higher arthropod richness could be obtained using this eDNA approach. Overall, our results demonstrate that it is possible to obtain information on diverse communities of insects and other terrestrial arthropods from eDNA metabarcoding of wild flowers. This novel source of eDNA represents a vast potential for addressing fundamental research questions in ecology, obtaining data on cryptic and unknown species of plant‐associated arthropods, as well as applied research on pest management or conservation of endangered species such as wild pollinators.     

CUTICULAR LIPIDS OF TERRESTRIAL PLANTS AND ARTHROPODS: A COMPARISON OF THEIR STRUCTURE, COMPOSITION, AND WATERPROOFING FUNCTION

1. Lipids deposited on the surface or embedded within the cuticle of terrestrial plants and arthropods are primarily responsible for the observed low rates of water loss through the cuticle. 2. These lipids are a mixture of long-chain compounds which include hydrocarbons (saturated, unsaturated, branched), wax esters, free fatty acids, alcohols, ketones, aldehydes, and cyclic compounds. 3. The cuticle of both plants and arthropods is a continuous, non-cellular multilayered membrane which overlies the epidermal cells. 4. In arthropods, horizontal division of the cuticle into layers is clearly visible. In plants, the layers comprising the cuticle are not sharply demarcated. 5. The substance responsible for the structural integrity of the plant cuticle (cutin) is composed of cross-esterified fatty acids; structural integrity in arthropod cuticle is provided by a chitin-protein complex. 6. Cuticular lipids are probably formed near the surface in both plants and arthropods; however, specific sites of synthesis are known for only a few species and little is known about their transport from these sites to the surface. The elaborate pore canal and wax canal system of arthropod cuticle is absent from plants. 7. The physical structure and arrangement of the lipid deposits on the cuticular surface that are so important in controlling water movement depend on both quantity and chemical composition, and are, in turn, specific to each species in relation to its environment. 8. Different lipid components are not equally efficient in reducing transpiration. Maximum waterproofing effectiveness is provided by long-chain, saturated, non-polar molecules containing few methyl branches. 9. Plants and arthropods can, within genetic constraints, alter the composition of their cuticular waxes to improve impermeability when conditions require increased water conservation. 10. None of the models proposed to explain the change in arthropod cuticular permeability which occurs at a species-specific temperature (‘transition temperature’) in many species is supported by the experimental data now available.     

甜槠凋落叶分解中土壤节肢动物群落结构动态及其对森林片段化的响应

选取浙、闽、赣交界山地5个不同的常绿阔叶林群落(1处连续森林和4处片段化森林),对优势种甜槠凋落叶分解过程中土壤节肢动物动态进行了研究.5个研究样地共获得土壤节肢动物899头,分属9纲25目,其中鳞翅目占个体总数的10%以上,为优势类群;膜翅目、弹尾目、双翅目、前气门亚目和地蜈蚣目为常见类群.凋落叶分解速率与土壤节肢动物的类群数、个体数随季节动态呈现相一致的变化趋势.8月凋落物分解最快,土壤节肢动物类群和个体数最多;而4至6月和12月情况与之相反.片段化森林和连续森林在土壤节肢动物的类群数、个体数和物种多样性方面均显示出差异,面积效应和边缘效应在其中都起了一定的作用.     

Inventory of terrestrial alien arthropod predators and parasites established in Europe

There are currently 1590 terrestrial arthropod species identified as alien to Europe. Of these, 513 are predators or parasites. The largest group is the insects (409 species), followed by spiders (47 species), myriapods (34 species) and mites (23 species). The species within these alien groupings are extremely diverse, as highlighted by the large number of families represented (115 families). The majority (66.1%) of alien arthropod predator and parasite species arrived unintentionally, but at least 174 (33.9%) have been introduced intentionally, mainly for biological control purposes. Assessment of the major invasion pathways is difficult due to the lack of comprehensive information but it is likely that the majority of predatory or parasitic alien arthropods arrive through leading-edge dispersal or as contaminants and stowaways. The number of new species arriving in Europe has progressively increased since 1500, with the increase in global trade over the last century accelerating this rate of increase. Only a small number of alien predatory and parasitic arthropods in Europe have been shown to cause either an ecological or economical impact, yet knowledge is severely limited by a paucity of data.     

Aerial arthropod communities of native and invaded forests, Robinson Crusoe Island, Chile

Invasive species significantly contribute to biological change and threaten biodiversity, with a growing body of evidence that plant invasions affect higher trophic levels. We explored the relative importance of plant invasion and forest structure on aerial arthropod abundance, diversity, and composition on Robinson Crusoe Island, Chile. We used flight intercept traps to sample aerial arthropods within distinct canopy strata of native and invaded forests over 3-mo periods in 2006 and 2007. Arthropod abundance and diversity were higher in native than invaded forest, and arthropod communities were distinct between forest types. In both forest types, arthropod abundance was highest in the lower canopy, and canopy strata exhibited some differences in arthropod community composition. Several morphospecies were distinctly associated with each forest type. The strong differences in aerial arthropod communities associated with the invasion of native forest by non-native plants may affect other trophic levels, such as insectivorous birds. Steps to stop invasive plant spread and to restore native forest composition and structure are needed to safeguard the integrity of native communities, from plants to higher-level consumers.     

Herbivorous arthropods on bracken (Pteridium aquilinum (L.) Khun) in Australia compared with elsewhere

Abstract The herbivorous arthropod fauna of bracken fern (Pteridium aquilinum (L.) Khun), at a site near Sydney, Australia, is described and compared with previously reported bracken faunas in other geographic regions. Monthly sampling over 18 months found 17 species of herbivorous arthropods (15 insect and two mite species) from five orders. At the ordinal level, the mixture differed substantially from the bracken faunas of sites in Britain and Papua New Guinea. Notable was the presence of Thysanoptera and Acari, and the absence of Coleoptera and Hymenoptera. The mixtures of orders/families represented in the site bracken faunas in Britain, and less so in Australia, resembled those in the pool of herbivorous arthropods in those regions. Further, the mixture of orders on bracken was more similar to the mixture of orders on other ferns than to the mixture of orders among herbivorous insects on all plants; such similarity was not evident at family level. Compared with sites in other regions, the Sydney site had an abundance of pinna-sucking species and a dearth of mining species. Differences between regions in feeding niches most occupied tended to correspond with the differences in orders represented. Not all features of the fauna of bracken near Sydney reflected differences in the general herbivorous arthropod fauna of Australia compared with other regions, or differences between the herbivore faunas of ferns and seed plants. Its composition must be attributed in part to stochastic aspects of the speciation of herbivorous arthropods onto host plants.     

Diversity and conservation of forest-floor arthropods on a small Seychelles island

Cousine Island, Seychelles, is of major conservation significance as it is in a biodiversity hotspot. Furthermore, it is relatively pristine, and is apparently the only tropical island over 20 ha with no alien invasive mammals. This study focuses on the island's log and litter arthropods, which were sampled by extraction methods from the dominant species, Pisonia grandis, Ficus spp. and Cocos nucifera. Stage of decomposition, and forest type in which the logs occurred, both significantly influenced the composition and structure of the arthropod assemblages. Young logs were significantly richer in species than older logs, possibly because they had the most resources and microhabitats. There were some significant changes in arthropod species richness, composition and abundance between species of young logs, but not old ones, because as logs decomposed, arthropod assemblages converged. Nevertheless, each old log species had some arthropod species not present in other log species, which has important implications for conservation. Arthropod assemblages in woody litter varied according to the forest type in which they occurred, and were different from those in logs in the same forest type. Cousine Island arthropod species richness, both in logs and litter, was comparable to figures from other tropical areas. As the logs, especially P. grandis, are home to many Seychelles endemic species, their conservation is essential. Furthermore, as the arthropods are also the main food of certain threatened Seychelles vertebrates, their conservation also underpins a food chain on this unique tropical island.     

Effects of the emerald ash borer invasion on the community composition of arthropods associated with ash tree boles in Maryland,U.S.A.

相似文献   

The aquarium trade as a potential source of fish introductions in southwestern Europe

The aquarium trade has been identified as an important vector of aquatic invasive species but this question has mostly been investigated in North America. We investigated the variation in diversity and species composition in different trade types in southwestern Europe (three major international wholesalers, different retail store types, and local internet forums), mostly in Spain and Portugal. As in previous studies, the diversity of fishes in the aquarium trade was vast, with a total of 20 orders, 79 families, and 1,133 fish species detected in the trade types analyzed. 248 species were observed in a single metropolitan area (Barcelona), with estimates of about 294 species being present. International wholesalers had higher species richness and evenness, with a single one having over 700 species. General pet stores had much lower evenness but due to high turnover had a total richness of over 200 species. Internet forums had the lowest evenness but similar richness. The different commerce types varied significantly in relative species abundance with about a dozen of popular fish species (e.g., goldfish, Siamese fighting fish, common carp, guppy, swordtails) dominating the retail stores, particularly the general pet stores. Our results imply that frequency in the trade varies strongly among species and commerce types and although general pet stores have usually low diversity, this is compensated with a higher species turnover. Many of the most popular species are well known invasive species and some of the species available are temperate species that might establish in Europe, reinforcing the need for more careful implementation of education programs, regulation and monitoring of trade, and internalization of environmental costs by the industry.