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Mechanisms of Success: Plant-Herbivore Interactions and the Invasion of Non-native Lonicera Species in North America
Get PDFInvasion by non-native species is a complicated process and many hypotheses have been proposed to explain how invasive plant species are often poor competitors in their native range, but dominant in their novel range including the enemy release and novel weapons hypotheses. Additionally, many invasive species are characterized as being tolerant and/or resistant to both damage and limitations in abiotic resources. These hypotheses are based on plant-plant, plant-microbial, and plant-herbivore interactions in the invaders novel range and are not mutually exclusive. The genus Lonicera (Caprifoliaceae) includes approximately 200 species worldwide, with 18 native and 16 introduced species in North America. Some Asiatic species like Lonicera maackii, L. tatarica, and L. japonica are particularly successful invaders in North America, while North American natives are relatively uncommon or not abundant where they are found. I investigated the plant-insect interactions and defensive strategies of non-native Lonicera species, with particular focus on L. maackii in Ohio. I first quantified the amounts of arthropod herbivore damage occurring on L. maackii across two seasons. I expanded this assessment to include a co-occurring native congener L. reticulata and the confamiliar Viburnum prunifolium. Additionally, I included feeding bioassays to assess the performance of a specialist and generalist herbivore on native and non-native Lonicera species. Tolerance of mature shrubs was evaluated through measures of growth responses after repeated clipping. Greenhouse experiments with real and simulated herbivory were completed to determine the tolerance of juvenile L. maackii plants to herbivory and how this may be affected by changes in resource availability. Resistance traits were also evaluated in this experiment through measures of secondary metabolites with and without herbivory. Finally, resistance traits were further evaluated through a common garden experiment including multiple native and non-native Lonicera species, where herbivore damage, generalist herbivore performance, and both qualitative and quantitative analyses of defensive chemistry were evaluated in high and low nutrient treatments. Lonicera maackii and other non-native Lonicera species receive insignificant amounts of arthropod herbivore damage in the field and the damage they receive is much less than amounts incurred on native Lonicera and confamiliar V. prunifolium. Mature L. maackii shrubs are highly tolerant to large amounts of simulated herbivore damage, juvenile L. maackii is both tolerant and resistant to high amounts of real and artificial damage, and limiting light and soil nutrients did not limit their ability to tolerate herbivory. A honeysuckle specialist avoids L. maackii in the field, but can develop on L. maackii in the laboratory. Plants in the Lonicera genus that display resistance to arthropod herbivores can be characterized as being chemically well defended, and are generally poor hosts to generalist herbivores. Although native/non-native origin did not explain the chemical profiles of species, native Lonicera tended to produce more iridoid glycosides and non-native Lonicera produced more phenolic compounds. Lonicera maackii and other non-natives appear to not only escape damage from arthropod herbivores, they are also able to tolerate and resist the damage they do incur suggesting that a combination of mechanisms contribute to the success of these non-native Lonicera in North America
Environmental Influences on Growth and Defence Responses of the Invasive Shrub, Lonicera maackii, to Simulated and Real Herbivory in the Juvenile Stage
No full textTolerance and defence against herbivory are among the many mechanisms attributed to the success of invasive plants in their novel ranges. Because tolerance and defence against herbivory differ with the ontogeny of a plant, the effects of herbivore damage on plant fitness vary with ontogenetic stage and are compounded throughout a plant\u27s lifetime. Environmental stresses such as light and nutrient limitations can further influence the response of the plant. Much is known about the response of plants in the seedling and reproductive adult stages, but less attention has been given to the pre-reproductive juvenile stage
Two decades of data reveal that Biological Invasions needs to increase participation beyond North America, Europe, and Australasia
No full textMost published papers in ecology come from a handful of countries, and invasion science as an ecological subdiscipline is no exception. Based on the country of corresponding authors, we analyzed patterns in submissions, reviews, and publications in the journal Biological Invasions from its first issue in 1999 to 2020. Regionally, North America, Europe, and Australasia submitted and published the most articles during this period and supplied most reviewers and journal editors. As a country, the USA stands out in terms of papers published and reviewers involved in the process. The dominance of published articles from USA-based scientists declined through time, but such articles still constitute one-third of all articles in recent years. However, as biological invasions are a worldwide phenomenon acting on local to global scales, research from all regions of the world is needed to better understand and manage invasions. By tracking and reporting the trends in the countries of origin of the journal’s authors and reviewers, and by encouraging submissions from more countries, we hope that geographical differences will decrease and that a more global understanding of biological invasions will emerge.Fil: Nuñez, Martin Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. University of Houston; Estados UnidosFil: Chiuffo, Mariana Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Seebens, Hanno. Senckenberg Biodiversity And Climate Research Centre,; AlemaniaFil: Kuebbing, Sara. University of Pittsburgh; Estados UnidosFil: McCary, M. Rice University; Estados UnidosFil: Lieurance, Deah. University of Florida; Estados UnidosFil: Zhang, Bo. Oklahoma State University; Estados UnidosFil: Simberloff, D.. University of Tennessee; Estados UnidosFil: Meyerson, Laura. University of Rhode Island; Estados Unido
Exotic Lonicera Species both Escape and Resist Specialist and Generalist Herbivores in the Introduced Range in North America
No full textThe enemy release hypothesis predicts that invasive plant species may benefit from a lack of top-down control by co-evolved herbivores, particularly specialists, in their new range. However, to benefit from enemy escape, invasive plants must also escape or resist specialist or generalist herbivores that attack related species in the introduced range. We compared insect herbivore damage on the exotic shrub, Lonicera maackii, the native congener Lonicera reticulata, and the native confamilial Viburnum prunifolium in North America. We also compared the laboratory preference and performance of a North American honeysuckle specialist sawfly (Zaraea inflata) and the performance of a widespread generalist caterpillar (Spodoptera frugiperda) on cut foliage from native and exotic Lonicera species. L. maackiireceived significantly lower amounts of foliar herbivory than L. reticulata across three seasons, while damage levels observed on V. prunifolium for two seasons was generally intermediate between L. reticulata and L. maackii. The specialist sawfly damaged L. reticulata heavily, but was not detected on L. maackii in the field. There were few statistical differences in the performance of sawfly larvae on L. reticulata and L. maackii, but the sawfly achieved higher pupal masses on L. reticulata than on L. maackii, and they strongly preferred L. reticulata over L. maackii when given a choice. The sawfly was unable to complete development on native L. sempervirens and non-native L. japonica. In contrast, the generalist caterpillar performed similarly on all Lonicera species. While L. maackii experienced little herbivory in the field compared to native relatives in the same habitat, laboratory assays indicate L. maackii appears to be a suitable host that escapes selection by the specialist, but L. japonica and L. sempervirens are highly resistant to it. These findings indicate that both enemy escape and resistance (to a specialist, but not a generalist herbivore) may contribute to the success of exotic Lonicera species
Expression and Costs of Induced Defense Traits in Alliaria petiolata, a Widespread Invasive Plant
No full textWe used jasmonic acid to induce first-year plants of Alliaria petiolata, a European invader that largely escapes herbivory in North America, to examine continental, population, and environmental variation in the expression and costs of induced defense traits. While absolute levels varied among populations, the induction of trypsin inhibitor activity was strong and largely uniform across five native and seven invasive populations. Trichome densities varied across populations, were absent in two of them, and only tended to be inducible by jasmonic acid. Jasmonate induction was substantially costly to leaf growth and dry biomass production, the magnitude of which varied little among populations. Continental origin of the populations explained an insignificant amount of variation in any trait. Trypsin inhibitor activity was strongly inducible across a nutrient gradient, but induction was more costly to leaf growth at low soil nutrient levels. Our results show that A. petiolata displays defense traits that are strongly inducible by jasmonic acid across populations, that jasmonate induction is substantially costly to growth with little variation among populations, and that costs of induction increase with decreased soil nutrient availability. Escaping the need to express induced defense traits and their costs in the face of reduced herbivory in introduced habitats may benefit fitness of invasive plants even in the absence of any evolutionary change in resistance in these plants
A self-study of editorial board diversity at Biological Invasions
No full textThe editorial board of this journal, Biological Invasions, aims to publish research that informs understanding of the patterns and processes of invasions and discussion of relevant policy and conservation issues related to controlling invasions. Because the scope of the journal's interests is global, building an editorial board that represents the demographic, geographic, and topical diversity within the invasion sciences would best serve the journal's readership and reflect the scope of Biological Invasions' global interests. We suspect that an editorial board comprised of members representing the diversity in invasion science can improve data and knowledge on biological invasions and increase participation in Biological Invasions' publication process from more geographic regions and diverse perspectives. To initiate a process of self-reflection and a discussion on editorial representation at Biological Invasions, we are, for the first time, reporting demographic data for the historical and current editorial board membership. As of January 2021, we find skewed representation of certain demographic, geographic, and topical expertise. Over 85% of editors identify as white, > 70% speak English as their primary language, > 60% identify as male, and nearly 50% of editors are nationals of the United States. The editorship predominantly conducts research in temperate biomes, with most editors considering plants or invertebrates as their organismal expertise. These results highlight geographic and topical areas with uneven expertise that can guide us as we work to diversify the board of Biological Invasions.Fil: Kuebbing, Sara E.. University of Pittsburgh; Estados UnidosFil: McCary, Matthew A.. Rice University; Estados UnidosFil: Lieurance, Deah. University of Florida; Estados UnidosFil: Nuñez, Martin A.. University of Houston; Estados UnidosFil: Chiuffo, Mariana Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Zhang, Bo. Oklahoma State University; Estados UnidosFil: Seebens, Hanno. Senckenberg Biodiversity And Climate Research Centre; AlemaniaFil: Simberloff, Daniel. University of Tennessee; Estados UnidosFil: Meyerson, Laura A.. University of Rhode Island; Estados Unido
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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