Recent emergence and worldwide spread of the red tomato spider mite, <Emphasis Type="Italic">Tetranychus evansi</Emphasis>: genetic variation and multiple cryptic invasions

Plant biosecurity is increasingly challenged by emerging crop pests. The spider mite Tetranychus evansi has recently emerged as a new threat to solanaceous crops in Africa and the Mediterranean basin, with invasions characterized by a high reproductive output and an ability to withstand a wide range of temperatures. Mitochondrial (868 bp of COI) and nuclear (1,137 bp of ITS) loci were analyzed in T. evansi samples spanning the current geographical distribution to study the earliest stages of the invasive process. The two sets of markers separate the samples into two main clades that are only present together in South America and Southern Europe. The highest COI diversity was found in South America, consistent with the hypothesis of a South American origin of T. evansi. Among the invaded areas, the Mediterranean region displayed a high level of genetic diversity similar to that present in South America, that is likely the result of multiple colonization events. The invasions of Africa and Asia by T. evansi are characterized by a low genetic variation associated with distinct introductions. Genetic data demonstrate two different patterns of invasions: (1) populations in the Mediterranean basin that are a result of multiple cryptic introductions and (2) emerging invasions of Africa and Asia, each likely the result of propagules from one or limited sources. The recent invasions of T. evansi illustrate not only the importance of human activities in the spread of agricultural pests, but also the limits of international quarantine procedures, particularly for cryptic invasions.     

Uncertainties in Predicting Species Distributions under Climate Change: A Case Study Using Tetranychus evansi (Acari: Tetranychidae), a Widespread Agricultural Pest

Many species are shifting their distributions due to climate change and to increasing international trade that allows dispersal of individuals across the globe. In the case of agricultural pests, such range shifts may heavily impact agriculture. Species distribution modelling may help to predict potential changes in pest distributions. However, these modelling strategies are subject to large uncertainties coming from different sources. Here we used the case of the tomato red spider mite (Tetranychus evansi), an invasive pest that affects some of the most important agricultural crops worldwide, to show how uncertainty may affect forecasts of the potential range of the species. We explored three aspects of uncertainty: (1) species prevalence; (2) modelling method; and (3) variability in environmental responses between mites belonging to two invasive clades of T. evansi. Consensus techniques were used to forecast the potential range of the species under current and two different climate change scenarios for 2080, and variance between model projections were mapped to identify regions of high uncertainty. We revealed large predictive variations linked to all factors, although prevalence had a greater influence than the statistical model once the best modelling strategies were selected. The major areas threatened under current conditions include tropical countries in South America and Africa, and temperate regions in North America, the Mediterranean basin and Australia. Under future scenarios, the threat shifts towards northern Europe and some other temperate regions in the Americas, whereas tropical regions in Africa present a reduced risk. Analysis of niche overlap suggests that the current differential distribution of mites of the two clades of T. evansi can be partially attributed to environmental niche differentiation. Overall this study shows how consensus strategies and analysis of niche overlap can be used jointly to draw conclusions on invasive threat considering different sources of uncertainty in species distribution modelling.     

Identification of priority areas in South America for exploration of natural enemies for classical biological control of Tetranychus evansi (Acari: Tetranychidae) in Africa

The red spider mite Tetranychus evansi Baker and Pritchard is a pest of tomato in East and Southern Africa. It is probably native to South America. Three models were established to identify priority areas for the search of natural enemies in South America for classical biological control of this pest in Africa. The models were based on the concept of “fundamental ecological niche”, predicting regions in South America that have similar environmental conditions to areas where the mite is a problem in Africa, using Desktop-GARP (Genetic Algorithm for Rule-set Production). Based on the model established with data sets from Kenya and Zimbabwe, it was determined that priority areas include areas in Brazil, Argentina, Paraguay and Uruguay, as well as some restricted areas in other South American countries.     

Impact of natural epizootics of the fungal pathogen Neozygites floridana (Zygomycetes: Entomophthorales) on population dynamics of Tetranychus evansi (Acari: Tetranychidae) in tomato and nightshade

The tomato red spider mite, Tetranychus evansi (Acari: Tetranychidae) was recently introduced in Africa and Europe, where there is an increasing interest in using natural enemies to control this pest on solanaceous crops. Two promising candidates for the control of T. evansi were identified in South America, the fungal pathogen, Neozygites floridana and the predatory mite Phytoseiulus longipes. In this study, population dynamics of T. evansi and its natural enemies together with the influence of environmental conditions on these organisms were evaluated during four crop cycles in the field and in a protected environment on nightshade and tomato plants with and without application of chemical pesticides. N. floridana was the only natural enemy found associated with T. evansi in the four crop cycles under protected environment but only in the last crop cycle in the field. In the treatments where the fungus appeared, reduction of mite populations was drastic. N. floridana appeared in tomato plants even when the population density of T. evansi was relatively low (less than 10 mites/3.14 cm² of leaf area) and even at this low population density, the fungus maintained infection rates greater than 50%. The application of pesticides directly affected the fungus by delaying epizootic initiation and contributing to lower infection rates than unsprayed treatments. Rainfalls did not have an apparent impact on mite populations. These results indicate that the pathogenic fungus, N. floridana can play a significant role in the population dynamics of T. evansi, especially under protected environment, and has the potential to control this pest in classical biological control programs.     

The potential global distribution of the Bronze bug Thaumastocoris peregrinus Carpintero and Dellapé (Hemiptera: Thaumastocoridae)

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Review of the invasion of Tetranychus evansi: biology, colonization pathways, potential expansion and prospects for biological control

In the last two decades the subtropical red tomato spider mite, Tetranychus evansi, has expanded its geographical distribution and emerged as a major invasive agricultural pest. The mite is considered to be native to South America. Since its first report from north-eastern Brazil in 1952, it has been reported from different continents. This paper reviews literature on several aspects of the biology of T. evansi related to its status as an invasive species. It addresses taxonomical issues, occurrences, life history traits, host-plant interactions, genetic diversity of geographical isolates and worldwide colonisation pathways. It also presents updated data which allowed the assessment of the actual worldwide distribution of this species, from its discovery to the latest reports. As T. evansi is considered an emerging agricultural pest, we also present data based on modelling of the potential of T. evansi to colonize new geographical areas. In addition, this review presents past and current research on natural enemies of T. evansi potentially useful for its biological control. While summarizing the knowledge on T. evansi, the review emphasizes research possibilities that are worth pursuing, mainly concerning the ability of T. evansi to establish new populations and to detect new promising natural enemies.     

Life tables of the predatory mite Phytoseiulus longipes feeding on Tetranychus evansi at four temperatures (Acari: Phytoseiidae, Tetranychidae)

The tomato red spider mite, Tetranychus evansi, is reported as a severe pest of tomato and other solanaceous crops from Africa, from Atlantic and Mediterranean Islands, and more recently from the south of Europe (Portugal, Spain and France). A population of the predaceous mite Phytoseiulus longipes has been recently found in Brazil in association with T. evansi. The objective of this paper was to assess the development and reproduction abilities of this strain on T. evansi under laboratory conditions at four temperatures: 15, 20, 25 and 30°C. The duration of the immature phase ranged from 3.1 to 15.4 days, at 30 and 15°C, respectively. Global immature lower thermal threshold was 12.0°C. Immature survival was high at all temperatures tested (minimum of 88% at 30°C). The intrinsic rate of increase (r _m) of P. longipes ranged from 0.091 to 0.416 female/female/day, at 15 and 30°C, respectively. P. longipes would be able to develop at a wide range of temperatures feeding on T. evansi and has the potential to control T. evansi populations.     

Reproductive performance of seven strains of the tomato red spider mite <Emphasis Type="Italic">Tetranychus evansi</Emphasis> (Acari: Tetranychidae) at five temperatures

The tomato red spider mite Tetranychus evansi Baker et Pritchard occurs on solanaceous plants, and causes serious damage to a variety of crops in Africa and Europe. In 2001 this species was also found in Japan, on nightshade (Solanum nigrum L.), and its invasion to solanaceous of agricultural importance is feasible. To evaluate its potential severity as a pest, the present study assessed the life-history parameters, such as the rate of development and the intrinsic rate of natural increase (r _m), on S. nigrum for T. evansi collected on seven sites worldwide. Increasing temperatures between 15 and 32.5°C significantly increased the developmental rate of the seven strains while immature developmental duration was about the same at 32.5–40°C. The rate of egg-to-adult development [(% hatch) × (% survival)] exceeded 88% at temperatures between 15 and 37.5°C. The lower thermal thresholds (LT) were 11.9–12.5°C for both egg-to-adult and egg-to-egg development. The optimum developmental temperatures ranged from 36.7 to 43.8°C and the upper developmental threshold (UT) ranged from 45.2 to 59.4°C. The r _m-values became higher with temperature increasing from 15 to 35°C. The r _m-values at 25°C ranged from 0.265 to 0.277 which are relatively high for species of the genus Tetranychus. These results indicate that T. evansi after invasion into Japan has the potential to become a serious pest on solanaceous crops, just the same as in Africa and Europe.     

Environmental suitability of new reported localities of the funnelweb spider Macrothele calpeiana: an assessment using potential distribution modelling with presence‐only techniques

Aim The funnelweb spider Macrothele calpeiana is endemic to the southern half of the Iberian Peninsula, but recent occurrence records from localities in Spain, North Africa and other regions of Europe, which are distant from its native populations, suggest human‐mediated dispersal, probably associated with the commercial export of olive trees. The main goal of this study was to assess the environmental suitability of these new records and to discuss the spider’s potential to become an invasive species, mainly in new regions across Central Europe and the Mediterranean Basin. Location Central Europe, Mediterranean Basin. Methods Using presence points from the Iberian native populations of M. calpeiana and a set of climatic variables, four presence‐only algorithms (BIOCLIM, DOMAIN, GARP and Maxent) were applied to model the potential distribution of the spider. The models were transferred to Central Europe and the Mediterranean Basin, and the locations of the new records in both the occupied and potential environmental spaces were screened. Results The four models were generally congruent in predicting the existence of a suitable climate for the species across the Mediterranean Basin, although BIOCLIM and DOMAIN yielded more constrained predictions than GARP and Maxent. Whereas the new records from Central Europe were located far from the occupied and potential climatic spaces, those from the Iberian Peninsula were not. Main conclusions Climatic suitability together with propagule pressure owing to human activities will certainly enhance the opportunities for M. calpeiana to colonize new areas across the Mediterranean Basin. The species has invaded areas beyond its native range, and those new locations located in the Iberian Peninsula and North Africa show environmental suitability for the spider and deserve long‐term monitoring. Although the new locations in Central Europe were not predicted by the climate models and the persistence of the species seems improbable, the possibility of rapid evolution or phenotypic plasticity processes raises the need for caution over the possibility of a future spread of M. calpeiana across Europe. Stronger controls over the transport of trees must be applied, and further studies on the ecology of the spider are imperative to assess the possible impact on the invaded ecosystems.     

Search for effective natural enemies of Tetranychus evansi in south and southeast Brazil

Tetranychus evansi Baker & Pritchard is an important pest of Solanaceae in several countries. Introduced accidentally to Africa, it presently occurs in many countries of that continent. In some of them, it is considered a key pest. The suspected area of origin of this mite is South America. The objective of the present study was to identify phytoseiid mites on solanaceous plants in association with T. evansi in south and southeast Brazil for introduction in the African continent for use in a classic biological control program. Almost 1,400 predatory mites of the family Phytoseiidae were collected, on 22 solanaceous species. The Amblyseiinae were the most diverse group in this study. Twenty-three of the species found belong to this subfamily, while only three belong to the Typhlodrominae and two to the Phytoseiinae. The most abundant and most frequent phytoseiid species were Phytoseius guianensis De Leon and Galendromus annectens (De Leon) of the Phytoseiinae and Typhlodrominae, respectively. The most frequent and abundant species of Amblyseiinae was Neoseiulus tunus (De Leon). Phytoseius guianensis and N. tunus were never found in association with T. evansi and G. annectens was found only once in association with it. Two factors suggested Phytoseiulus longipes Evans as the most promising predator found in this study. It could walk very well on tomato leaves infested by T. evansi, without being hampered by the profuse webbing produced by the prey and by the trichomes. In addition, several specimens of both sexes including eggs and nymphs of the predator were found associated with T. evansi on three different plant species and in two different periods of the year, when T. evansi was the only arthropod present on the leaves.     

Direct and indirect adverse effects of tomato on the predatory mite Neoseiulus californicus feeding on the spider mite Tetranychus evansi

Plants may defend themselves against herbivores via morphological traits, chemical traits, or a combination of both. Herbivores that overcome the defensive mechanisms of a plant tend to specialize on this plant due to enhanced protection from natural enemies. Well‐known examples of plants possessing a suite of defensive mechanisms are found in nightshades (Solanaceae), especially in the tomato genus Lycopersicon. The spider mite Tetranychus evansi Baker and Pritchard (Acari: Tetranychidae) is specialized on solanaceous plants and is an invasive pest of tomato in Europe and Africa. Biological control of T. evansi with currently available natural enemies, such as the predatory mites Phytoseiulus persimilis Athias‐Henriot and Neoseiulus californicus McGregor (both Acari: Phytoseiidae), is unsuccessful, with the underlying mechanisms only vaguely known. We hypothesized that T. evansi is a key pest of tomato because this host plant provides a two‐pronged protection from natural enemies. Direct adverse effects of tomato on predators may arise from morphological traits and/or trichome exudates, whereas indirect effects are prey‐mediated through the accumulation of toxic plant compounds. Using a 2 × 3 factorial design, we assessed and separated direct and indirect effects of tomato on the life history of N. californicus feeding on two strains of T. evansi (reared on bean or tomato) on three substrates (tomato leaf, bean leaf, and an artificial cage). Developmental time and oviposition rate of N. californicus were both directly and indirectly negatively affected by tomato whereas offspring sex ratio and survival of juveniles and adult females were unaffected. The direct and indirect, prey‐mediated adverse effects of tomato on N. californicus with T. evansi prey had similar magnitudes and were additive. We conclude that T. evansi per se is a suitable prey species for N. californicus and discuss the results with respect to the potential use of N. californicus as biological control agent of T. evansi on tomato and other host plants.     

Potential Global Range Expansion of the Invasive Fire Ant, Solenopsis invicta

The red imported fire ant, Solenopsis invicta Buren, is an invasive pest that has become widespread in the southern United States and Caribbean after introduction from South America in the 1930s. This species, which has diverse detrimental impacts on recipient communities, was recently discovered in Australia and New Zealand and has the potential to colonize numerous other regions. We used a dynamic, ecophysiological model of colony growth to predict the potential global range expansion of this invasive species. Based on minimum and maximum daily temperatures, the model estimates colony alate production and predicts future geographic range limits. Because S. invicta populations are limited by arid conditions as well as cold temperatures, we superimposed precipitation data upon temperature-based predictions, to identify regions that do not receive enough rainfall to support this species across the landscape. Many areas around the globe, including large portions of Europe, Asia, Africa, Australia, and numerous island nations, are at risk for S. invicta infestation. Quarantine officials should be vigilant for any accidental introductions of this pest in susceptible regions. Costs of eradication increase dramatically as the area of infestation grows, and large infestations may be impossible to eradicate. Other South American Solenopsis fire ants (e.g., S. richteri Forel) may become invasive if the opportunity arises, and our predictions for S. invicta may approximate the potential range limits for these species as well.     

Global invasion by <Emphasis Type="Italic">Anthidium manicatum</Emphasis> (Linnaeus) (Hymenoptera: Megachilidae): assessing potential distribution in North America and beyond

The wool carder bee, Anthidium manicatum, is the most widely distributed unmanaged bee in the world. It was unintentionally introduced to North America in the late 1960s from Europe, and subsequently, into South America, New Zealand and the Canary Islands. We provide information on the local distribution, seasonal abundance and sex ratio of A. manicatum from samples collected in an intensive two-year survey across Utah, USA. Anthidium manicatum was detected in 10 of the 29 Utah counties, largely in urban and suburban settings. Combining presence-only and MaxEnt background data from literature, museum databases and new records from Utah, we constructed three species distribution models to examine the potential distribution of A. manicatum in its native Eurasian range as well as invaded ranges of North and South America. The A. manicatum model based on locality and background data from the species’ native range predicted 50% of the invasive records associated with high habitat suitability (HS ≥ 0.90). The invasive North American model predicted a much broader distribution of A. manicatum (214% increase); whereas, the South American model predicted a narrower distribution (88% decrease). The poor predictive power of the latter model in estimating suitable habitats in the invasive South American range of A. manicatum suggests that the bee may still be limited by the bioclimatic constraints associated with a novel environment. Estimates of niche similarity (D) between the native and invasive models find that the North America bioclimatic niche is more similar to the bioclimatic niche of the native model (D = 0.78), whereas the bioclimatic niche of the South America invasion is relatively dissimilar (D = 0.69). We discuss the naturalization of A. manicatum in North America, possibly through punctuated dispersal, the probability of suitable habitats across the globe and the synanthropy exhibited by this invasive species.     

Invasive and flexible: niche shift in the drosophilid <Emphasis Type="Italic">Zaprionus indianus</Emphasis> (Insecta,Diptera)

Although predictions of potential distributions of invasive species often assume niche conservatism, recent analyses suggest that niche shifts can also occur. Thus, further studies are necessary to provide a better understanding of niche dynamics and to predict geographic distribution in invaded areas. The present study investigated the niche shift hypothesis at a broad biogeographical scale, using the comprehensive distribution of the invasive species Zaprionus indianus in its native (Africa) and invaded (America and India) ranges. Z. indianus is a very successful invasive species that presents high adaptive flexibility and extreme physiological tolerance. To investigate whether Z. indianus changed its climatic niche from Africa to America and India, multivariate analyses, as well as ecological niche modeling procedures (GARP, MAXENT and Mahalanobis distances), were used. Multivariate analyses showed that the niche spaces of Z. indianus in Africa, India and the Americas were significantly different (Wilks’ λ from a Multivariate Analysis of Variance, MANOVA = 0.115; P < 0.0001). Out of 108 occurrences in America, only 11 (ca 10%) were classified, by Canonical Variate Analysis scores, as belonging to its original range in Africa, whereas only 5% of the 39 occurrences in India were classified as belonging to Z. indianus’ original range. Consensus results from MAXENT, GARP and Mahalanobis distances correctly predicted only 27% of the occurrences in India and 85% of occurrences in America. Thus, all analyses showed that Zaprionus indianus quickly expanded ranges into different environments in the invaded areas, suggesting climatic niche shifts, primarily in India.     

Life-history of predatory mites Neoseiulus californicus and Phytoseiulus persimilis (Acari: Phytoseiidae) on four spider mite species as prey, with special reference to Tetranychus evansi (Acari: Tetranychidae)

The commercially available strains of Phytoseiulus persimilis Athias-Henriot, the biological control agent of Tetranychus urticae Koch, perform poorly in the Western Mediterranean, probably because they are not well adapted to local climatic conditions. For that reason, efforts are being focused on the development of a biological control programme using native phytoseiid mites. Four species of red spider mites can be found in vegetable crops in eastern Spain: T. urticae, Tetranychus turkestani Ugarov and Nikolski, Tetranychus ludeni Zacher and the recently introduced Tetranychus evansi Baker and Pritchard. To evaluate their potential role as biological control agents, the present study evaluates the life-history of local populations of Neoseiulus californicus (McGregor) and P. persimilis when fed on T. urticae, T. turkestani, T. evansi, and T. ludeni in the laboratory. Results indicate that N. californicus and P. persimilis are able to feed and complete their development on the four tested red spider mite species. The predators may exhibit a particularly high capacity for population increase when fed on T. urticae, T. turkestani, and T. ludeni, thus may be able to provide effective control of these species in the field. When fed T. evansi, however, predator performance was poor; significant increase in development and preoviposition times, and a reduction in oviposition period and fecundity were recorded. The resultant low capacity for population growth suggests poor ability of the two tested predators to suppress T. evansi populations on commercial crops. It is unlikely therefore that P. persimilis and N. californicus, now being widely used to control T. urticae in greenhouse crops in Central Europe, will be able to halt any spread of T. evansi to greenhouse crops in temperate areas.     

The invasive spider mite Tetranychus evansi (Acari: Tetranychidae) alters community composition and host-plant use of native relatives

The tomato spider mite Tetranychus evansi Baker and Pritchard (Acari: Tetranychidae), is a worldwide pest of solanaceous crops that has recently invaded many parts of the world. In the present study we examined the ecological impact of its arrival in the Mediterranean region. The spider mite and phytoseiid mite assemblages in various crop and non-crop plants in three areas of Valencia (Spain) were studied a few months before and 10 years after the invasion of T. evansi. According to rarefaction analyses, the invasion of T. evansi did not affect neither the total number of species in the mite community examined (spider mite and phytoseiid species) nor the number of species when the two communities were examined separately. However, after the invasion, the absolute and relative abundance of the native Tetranychus species was significantly reduced. Before the invasion, T. urticae and T. turkestani were the most abundant spider mites, accounting for 62.9 and 22.8 % of the specimens. After the invasion, T. evansi became the most abundant species, representing 60 % of the total spider mites recorded, whereas the abundance of T. urticae was significantly reduced (23 %). This reduction took place principally on non-crop plants, where native species were replaced by the invader. Null model analyses provided evidence for competition structuring the spider mite community on non-crop plants after the invasion of T. evansi. Resistance to acaricides, the absence of efficient native natural enemies, manipulation of the plant defenses and the web type produced by T. evansi are discussed as possible causes for the competitive displacement.     

Modelling species distributions to predict areas at risk of invasion by the exotic aquatic New Zealand mudsnail Potamopyrgus antipodarum (Gray 1843)

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Predicting the potential geographical distribution of the harlequin ladybird, Harmonia axyridis, using the CLIMEX model

Harmonia axyridis (Pallas, 1773) (Coleoptera: Coccinellidae) is a ladybird beetle native to temperate and subtropical parts of Asia. Since 1916 populations of this species have been introduced throughout the world, either deliberately, or by accident through international transport. Harmonia axyridis was originally released as a classical biological control agent of aphid and coccid pests in orchards and forests, but since 1994 it is also available as a commercial product for augmentative control in field and greenhouse crops. It is a very voracious and effective natural enemy of aphids, psyllids and coccids in various agricultural and horticultural habitats and forests. During the past 20 years, however, it has successfully invaded non-target habitats in North America (since 1988), Europe (1999) and South America (2001) respectively in a short period of time, attacking a wide range of non-pest species in different insect orders. Becoming part of the agricultural commercial pathway, it is prone to being introduced into large areas across the world by accident. We use the CLIMEX programme (v2) to predict the potential geographical distribution of H. axyridis by means of matching the climate of its region of origin with other regions in the world and taking in account biological characteristics of the species. Establishment and spread seem likely in many regions across the world, including those areas which H. axyridis has already invaded (temperate Europe, North America). Based on the CLIMEX prediction a large part of Mediterranean Europe, South America, Africa, Australia and New Zealand seem highly suitable for long-term survival of H. axyridis as well. In addition we evaluate CLIMEX as a strategic tool for estimating establishment potential as part of an environmental risk assessment procedure for biological control agents we discuss biological and ecological aspects necessary to fine-tune its establishment and spread in areas after it has been introduced.     

New mite invasions in citrus in the early years of the 21st century

Several mite species commonly attack cultivated citrus around the world. Up to 104 phytophagous species have been reported causing damage to leaves, buds and fruits, but only a dozen can be considered major pests requiring control measures. In recent years, several species have expanded their geographical range primarily due to the great increase in trade and travel worldwide, representing a threat to agriculture in many countries. Three spider mite species (Acari: Tetranychidae) have recently invaded the citrus-growing areas in the Mediterranean region and Latin America. The Oriental red mite, Eutetranychus orientalis (Klein), presumably from the Near East, was detected in southern Spain in 2001. The Texas citrus mite, Eutetranychus banksi (McGregor), is widely distributed in North, Central and South America. It was first reported in Europe in 1999 on citrus in Portugal; afterwards the mite invaded the citrus orchards in southern Spain. In Latin America, the Hindustan citrus mite, Schizotetranychus hindustanicus (Hirst), previously known only from citrus and other host plants in India, was reported causing significant damage to citrus leaves and fruits in Zulia, northwest Venezuela, in the late 1990s. Later, this mite species spread to the southeast being detected on lemon trees in the state of Roraima in northern Brazil in 2008. Whereas damage levels, population dynamics and control measures are relatively well know in the case of Oriental red mite and Texas citrus mite, our knowledge of S. hindustanicus is noticeably scant. In the present paper, information on pest status, seasonal trends and natural enemies in invaded areas is provided for these species, together with morphological data useful for identification. Because invasive species may evolve during the invasion process, comparison of behavior, damage and management options between native and invaded areas for these species will be useful for understanding the invader’s success and their ability to colonize new regions.     

入侵害虫蔗扁蛾在我国的潜在分布区

【目的】蔗扁蛾是危害巴西木、甘蔗等园林植物和经济作物的重要入侵害虫。该虫于20世纪90年代初在我国被发现,现已分布在海南、广东和上海等19个省市,并有迅速扩散蔓延的趋势。对入侵害虫的潜在分布区进行预测,可为实施害虫监测和管理提供参考。【方法】根据蔗扁蛾已有分布点的记录,分别在4种地理区域构建Maxent生态位模型,并采用加权平均值法对其进行整合,进而分析蔗扁蛾在我国的潜在分布区。【结果】基于4种地理区域构建的Maxent模型对我国南部地区的预测结果基本一致,4种模型的预测差异主要在新疆北部和西南部、黑龙江东部和西部、吉林西部、山西中部等地区。整合模型显示,华东和华南地区以及东部沿海地区具有较大的分布可能性。【结论】蔗扁蛾在我国尤其是南方具有较大的潜在分布空间。这些地区应警惕蔗扁蛾的入侵,同时采取应对措施防止其进一步扩散。