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International audience; Iron formations (IFs) are chemical sedimentary rocks that were widely deposited before the Great Oxidation Event (GOE) around 2.4–2.2 Ga. It is generally thought that IFs precipitated as hydrated Fe3+ oxides (HFOs) such as ferrihydrite following surface oxidation of Fe2+-rich, anoxic deep waters. This model often implicates biological oxidation and underpins reconstructions of marine nutrient concentrations. However, nanoscale petrography indicates that an Fe2+ silicate, greenalite, is a common primary mineral in well-preserved IFs, motivating an alternative depositional model of anoxic ferrous silicate precipitation. It is unclear, however, if Fe2+-rich silicates can produce the Fe isotopic variations in IFs that are well explained by Fe2+ oxidation. To address this question, we constrain the equilibrium Fe isotopic (56Fe/54Fe) fractionation of greenalite and ferrihydrite by determining the iron phonon densities of states for those minerals. We use ab initio density functional theory (DFT + U) calculations and nuclear resonant inelastic X-ray scattering spectroscopy to show that ferrous greenalite should be isotopically lighter than ferrihydrite by ∼1–1.2‰ at equilibrium, and fractionation should scale linearly with increasing Fe3+ content in greenalite. By anchoring ferrihydrite–greenalite mineral pair fractionations to published experimental Fe isotopic fractionations between HFOs and aqueous Fe2+, we show that ferrous greenalite may produce all but the heaviest pre-GOE Fe isotopic compositions and mixed valence greenalites can produce the entire record. Our results suggest that heavy Fe isotope enrichments alone are not diagnostic of primary IF mineralogies, and ferrihydrite and partially oxidized or even purely ferrous greenalite are all viable primary IF mineralogie

CABI is a not-for-profit international organization with the mission of improving people’s lives worldwide by solving problems in agriculture and the environment, while engendering trust and facilitating science. As an organisation CABI is both a provider and a user of biological control agents and regularly acting as an intermediary between provider and user countries. As a way of building trust between both sides, access and benefit sharing (ABS) policy and ABS best practices developed around the principles of the Nagoya protocol should be publicly accessible. CABI aims to facilitate compliance with national legislation on ABS through its best practices for the countries in which we work and those that we provide genetic resources. CABI adopted the position to share benefits whether the provider country is party to the Nagoya Protocol or not. We use a case study on the biological control of the coffee berry borer (Hypothenemus hampei (Ferrari)) to illustrate the implementation of ABS best practices for the overlap between biological control and ABS. In respect to Digital Sequence Information (DSI) associated with genetic resources CABI contributes to the ongoing global debate and evaluates how this may impact biocontrol research and delivery. The current view is that publishing sequence data is sharing descriptive information and thus delivers benefit-sharing from its generation. However, if DSI is used in a product placed on the market, there is justification for benefit sharing.

The third objective of the Convention on Biological Diversity, the fair and equitable sharing of benefits arising out of the use of genetic resources was further developed when the Nagoya Protocol on Access and Benefit Sharing came into effect in 2014. Interpretation of how this agreement is being implemented is wide-ranging and there are implications for biological control. A survey of biological control workers indicated that while some countries have facilitated access to biological control genetic resources, requirements in other countries have impeded biological control implementation. There was consensus that benefits to provider countries should be in the form of supporting local research communities. There was also agreement that the free use and exchange of biological control genetic resources has provided benefits to the global community, including to both providers and recipients of the agents. It is recommended that consideration of the free use and exchange principal should be a key element of Access and Benefit Sharing measures for the future.

The Nagoya Protocol on Access and Benefit Sharing (ABS) was implemented to further develop the third objective of the Convention on Biological Diversity, the fair and equitable sharing of benefits arising out of the utilization of genetic resources. Interpretation of this agreement is wide-ranging and there is concern that if ABS measures are poorly implemented biological control and the resultant public good will be greatly impeded. The ethos of multilateral use and exchange of genetic resources used in classical biological control will be particularly affected. In the spirit of the fair and equitable sharing of benefits arising out of the utilization of genetic resources, we propose a simple practical solution in the form of an international agreement on the use and exchange of classical biological control genetic resources.

Recent reviews show that classical weed biocontrol measures can be successful in reducing the negative impacts of invasive plant species, have impressive returns on investment, and contribute to slower rates of weed spread. Quantitative post-release monitoring is necessary to account for differences in biocontrol outcomes across spatial and temporal scales. Direct nontarget attack (NTA) incidence and severity are decreasing over time, and pre-release host-specificity tests can accurately predict NTA post-release, as long as the nontarget plant species are included in testing. Less than 1% of NTA was found where the impacted plant species had been tested pre-release and was deemed not at risk. Effectiveness and environmental safety will likely further improve with the incorporation of new technologies, such as experimental evolutionary studies.

Development of a biological control program for invasive Phagmites australis australis in North America required 20 years of careful research, and consideration of management alternatives. A recent paper by Kiviat et al. (Biol Invasions 21:2529–2541, 2019. 10.1007/s10530-019-02014-9) articulates opposition to this biocontrol program and questions the ethics and thoroughness of the researchers. Here we address inaccuracies and misleading statements presented in Kiviat et al. (2019), followed by a brief overview of why biological control targeting Phragmites in North America can be implemented safely with little risk to native species. Similar to our colleagues, we are very concerned about the risks invasive Phragmites represent to North American habitats. But to protect those habitats and the species, including P. australis americanus, we come to a different decision regarding biological control. Current management techniques have not been able to reverse the invasiveness of P. australis australis, threats to native rare and endangered species continue, and large-scale herbicide campaigns are not only costly, but also represent threats to non-target species. We see implementation of biocontrol as the best hope for managing one of the most problematic invasive plants in North America. After extensive review, our petition to release two host specific stem miners was approved by The Technical Advisory Group for the Release of Biological Control Agents in the US and Canadian federal authorities.

Simple Summary Oxeye daisy, a Eurasian member of the daisy family, has become invasive in several parts of the world, including North America and Australia. We investigated whether a root-feeding moth found closely associated with oxeye daisy in Europe could be used as a biological control agent for the plant when weedy. We found that the moth could develop on 11 out of 74 plant species that we tested in laboratory conditions when it was given no choice of plants. When the moths were given a choice of food plants outdoors, we found its larvae only on the ornamentals Shasta daisy and creeping daisy. Larval feeding had no impact on the weight and number of flowers of Shasta daisy, but larval feeding and plant competition reduced both measurements for oxeye daisy. We conclude that it is safe to release the moth species because it will not affect the ornamental value of Shasta daisy or creeping daisy and because it is unlikely to harm any other economically important or native species. Based on the moth’s preference for oxeye daisy, and that we expect it to contribute to the suppression of the weed, we propose its field release in North America and Australia. Abstract We evaluated the potential of the European root-feeding moth Dichrorampha aeratana as a biological control agent for the invasive weed Leucanthemum vulgare (oxeye daisy) in North America and Australia. The taxonomic proximity of the ornamental Shasta daisy (Leucanthemum × superbum) to L. vulgare and its popularity in North America made finding sufficiently host-specific biological control agents a challenge. No-choice tests conducted with 74 non-target species revealed partial or complete larval development on 11 species. In multiple-choice oviposition and larval development tests that were conducted in field cages, larvae were found on five of these, however in multiple-choice tests conducted under open-field conditions, larvae were only found on the ornamentals Shasta daisy and creeping daisy (Mauranthemum paludosum). Larval feeding by D. aeratana had no measurable impact on Shasta daisy, but larval feeding and plant competition reduced the biomass and number of flower heads of L. vulgare. We conclude that D. aeratana is a suitable biological control agent because it will not affect the ornamental value of Shasta or creeping daisies and because it is unlikely to feed on any other economically important or native species. We also expect D. aeratana to contribute to the suppression of L. vulgare populations.

The inspection of tools in sheet-bulk metal forming poses special challenges for metrology. By using a fiber-optic fringe projection system, filigree, internal structures can be measured and the wear can be described by comparison with previous measurements.

Insect herbivores use olfactory and visual cues during host plant finding. Although insect responses to these cues typically are assessed separately, in nature herbivores respond to olfactory and visual cues simultaneously. We demonstrate the functionality of a “double-stacked y-tube device” (D-SYD) to measure bioassay responses of a specialist herbivore to olfactory and visual cues of potential host plants either presented individually or in combination. We tested the ability of the Eurasian specialist seed-feeding weevil, Mogulones borraginis, to distinguish between its Eurasian host, Cynoglossum officinale, which is invasive in North America, and a closely related confamilial native North American non-target, Andersonglossum occidentale. Weevils distinguished C. officinale from A. occidentale based on olfactory and visual cues. When olfactory and visual cues were offered simultaneously, weevils preferentially selected C. officinale more strongly and more rapidly than when either single cue was offered. When olfactory and visual cues were mismatched, weevils were no longer able to discriminate between the plant species and exhibited longer response times. There were no differences in behavioral responses to floral scents from greenhouse-propagated plants and those collected from plants in the field using a portable volatile collection system (PVCS). The bioassay approach demonstrated here using D-SYD and PVCS can assess behavioral responses of insects to olfactory and visual plant cues alone or together and measure their relative contributions to host discrimination. This will have utility for theoretical and applied questions concerning the host selection behavior of insect herbivores.

The foremost document that comprehensively reports on biological control introductions against weeds—‘Biological control of weeds: a world catalogue of agents and their target weeds’—has been updated and now includes all deliberate releases made through 2012. It includes data on 1555 intentional releases of 468 biological control agent species used against 175 species of target weeds in 48 plant families, in 90 countries. For 55 (31.4%) of the target weed species, only one biocontrol agent was introduced. The largest number of agent species (44) was introduced for the biological control of Lantana camara (Verbenaceae). Three insect orders (Coleoptera, Lepidoptera and Diptera) comprised about 80% of all biocontrol agent species released and releases made. Of the 468 biocontrol agent species introduced, 332 (70.9%) established in at least one instance. Of the 313 species, for which impact could be categorized, 172 (55.0%) caused medium, variable or heavy levels of damage (impacts). Of all releases made through 2012, 982 (63.2%) led to establishment. Forty-two releases were judged too early post-release to categorize impact, leaving 940 releases for which impact analyses were conducted. Similar to agent species, approximately half of the established releases (503 or 53.5%) caused medium, variable or heavy levels of damage on the target weeds, and almost a quarter of releases (225 or 23.9%) caused heavy impact. Across all countries and regions, 65.7% of the weeds targeted for biological control experienced some level of control. These data indicate the value of this practice, on its own, or as a supplement to other methods, in the management of invasive plants.

Biological control agents must be collected and utilised in compliance with the Nagoya Protocol on Access and Benefit Sharing (ABS) which is being implemented independently by each country that is signatory to the Protocol. By March 2018, 50 countries had legislation in place with an additional 54 designing their Legislative, Administrative or Policy Measures having become Party to the Protocol. Apart from the problem of dealing with the many different mechanisms countries are putting in place, it is often difficult to find relevant information on the ABS Clearing House and to access and receive appropriate responses from the National Focal Points or Competent National Authorities. We feel that a lot of time is lost on both sides (National authorities and scientists seeking information), and the process would benefit from streamlining. Also, open questions remain, such as how to deal with the generation digital sequence information and what specific activities are considered utilisation, especiall...

Despite their importance as invasive species, there has been a hesitation to target grasses in classical biocontrol. This historic bias appears to be changing with multiple active research and release programs. Similarly, biocontrol workers appear to avoid targeting species with native congeners. These biases appear inappropriate as the ecological and entomological literature provide abundant evidence for sub-genus specificity for many herbivores, including those attacking grasses. The biocontrol program targeting Phragmites australis (Cav.) Trin. ex Steud (Poaceae) provides an informative example with endemic subspecies in North America and many sub-genus specific herbivores, including potential European control agents. Grasses and target weeds with congeneric native species require rigorous host range testing, similar to all other targets in current weed biological control programs. Furthermore, it appears prudent to ask petition reviewers and regulatory agencies to abandon their focus on results of no-choice studies and to distinguish between trivial feeding and demographic impacts.

In weed biological control programs, pre-release host-specificity testing relies traditionally on no-choice and choice feeding, oviposition, and development tests. Rarely have they included detailed examination of behavioral responses to olfactory and visual cues of biological control candidates, although a better understanding of the mechanisms underlying host recognition may explain potential discrepancies between choice and no-choice tests, and/or between tests conducted in the lab versus field conditions. We investigated how the seed-feeding weevil, Mogulones borraginis, distinguishes its host plant, Cynoglossum officinale, from three native confamilial non-target species in North America. In behavioral bioassays, M. borraginis responded to olfactory and visual cues individually and, to an even greater extent, to both plant cue modalities when offered simultaneously. In tests with the combined cues, M. borraginis was attracted to C. officinale but responded with indifference or was repelled by non-target plants. In electrophysiological experiments, we identified that M. borraginis responded to ten volatile compounds and four wavelengths of lights from inflorescences of C. officinale. We propose that studies of responses to multimodal plant cues can advance our understanding of how biocontrol candidate species discriminate among host plants and closely related non-target species, thereby increasing the accuracy of environmental safety assessments pre-release.

Tree of heaven (Ailanthus altissima) is a fast-growing deciduous tree native to China, considered a serious invasive species worldwide, with several socio-economic and ecological impacts attributed to it. Chemical and mechanical methods have limited efficacy in its management, and biological controls may offer a suitable and sustainable option. Aculus mosoniensis (Ripka) is an eriophyid mite that has been recorded to attack tree of heaven in 13 European countries. This study aims to explore the host range of this mite by exposing 13 plant species, selected either for their phylogenetic and ecological similarity to the target weed or their economic importance. Shortly after inoculation with the mite, we recorded a quick decrease in mite number on all nontarget species and no sign of mite reproduction. Whereas, after just one month, the population of mites on tree of heaven numbered in the thousands, irrespective of the starting population, and included both adults and juveniles. Significantly, we observed evidence of damage due to the mite only on target plants. Due to the specificity, strong impact on the target, and the ability to increase its population to high levels in a relatively short amount of time, we find A. mosoniensis to be a very promising candidate for the biological control of tree of heaven.

Wu & Peek (2020) predict SDSS-quality spectra based on Pan-STARRS broad-band \textit{grizy} images using machine learning (ML). In this letter, we test their prediction for a unique object, UGC 2885 ("Rubin's galaxy"), the largest and most massive, isolated disk galaxy in the local Universe ($D

We have fit the far-ultraviolet (FUV) to sub-millimeter (850 micron) spectral energy distributions (SEDs) of the 61 galaxies from the "Key Insights on Nearby Galaxies: A Far-Infrared Survey with Herschel" (KINGFISH). The fitting has been performed using three models: the Code for Investigating GALaxy Evolution (CIGALE), the GRAphite-SILicate approach (GRASIL), and the Multi-wavelength Analysis of Galaxy PHYSical properties (MAGPHYS). We have analyzed the results of the three codes in terms of the SED shapes, and by comparing the derived quantities with simple "recipes" for stellar mass (Mstar), star-formation rate (SFR), dust mass (Mdust), and monochromatic luminosities. Although the algorithms rely on different assumptions for star-formation history, dust attenuation and dust reprocessing, they all well approximate the observed SEDs and are in generally good agreement for the associated quantities. However, the three codes show very different behavior in the mid-infrared regime, in particular between 25 and 70 micron where there are no observational constraints for the KINGFISH sample. We find that different algorithms give discordant SFR estimates for galaxies with low specific SFR, and that the standard "recipes" for calculating FUV absorption overestimate the extinction compared to the SED-fitting results. Results also suggest that assuming a "standard" constant stellar mass-to-light ratio overestimates Mstar relative to the SED fitting, and we provide new SED-based formulations for estimating Mstar from WISE W1 (3.4 micron) luminosities and colors. From a Principal Component Analysis of Mstar, SFR, Mdust, and O/H, we reproduce previous scaling relations among Mstar, SFR, and O/H, and find that Mdust can be predicted to within roughly 0.3 dex using only Mstar and SFR., 42 pages, 23 figures, 8 tables, 2 appendices: updated to v2, A&A, accepted

Lepidium draba (Brassicaceae) is a major concern for agriculture and biodiversity in the western United States. As current control methods do not provide long-term, sustainable solutions, research has been conducted to find biological control agents. Ceutorhynchus assimilis is one of the currently investigated candidates. Known as oligophagous in the literature, a specialist clade of this root-galling weevil exists in southern Europe. This raised the question of its ability to survive in colder climates in the target range. We investigated the phenology of C. assimilis in the field in southern France (specialist clade) and Romania (generalist clade) and measured various temperature-dependent parameters in the laboratory. In both ranges, weevils were univoltine. Oviposition in autumn started later in France compared to Romania, while mature larvae exited galls (to pupate in the soil) earlier the following year. On average, 25% and 32% of galls from France and Romania were completely below the soil surface, respectively, and this appeared to depend on soil substrate. Weevils transported from France to Romania were able to develop, but at a much lower rate than Romanian weevils. Mortality of overwintering larvae of both clades increased with decreasing temperature and exposure time. At −5°C, lethal times Lt50 and Lt95 were 15 and 42 days for the specialist clade and 26 and 72 days for the generalist clade. A higher proportion of third instar larvae compared to first and second instar larvae survived. Pupation time at different temperatures did not differ between weevils from France or Romania. A climate match model (comparing winter temperatures) indicated that the specialist clade of C. assimilis from France has the potential to establish in some parts of the target range (e.g. Washington, Oregon, California). However, temperature extremes and winters without snow cover will likely limit its establishment unless rapid adaptive evolution takes place.

Determinants of the host ranges of insect herbivores are important from an evolutionary perspective and also have implications for applications such as biological control. Although insect herbivore host ranges typically are phylogenetically constrained, herbivore preference and performance ultimately are determined by plant traits, including plant secondary metabolites. Where such traits are phylogenetically labile, insect hervivore host ranges are expected to be phylogenetically disjunct, reflecting phenotypic similarities rather than genetic relatedness among potential hosts. We tested this hypothesis in the laboratory with a Brassicaceae-specialized weevil, Ceutorhynchus cardariae Korotyaev (Coleoptera: Curculionidae), on 13 test plant species differing in their suitability as hosts for the weevil. We compared the associations between feeding by C. cardariae and either phenotypic similarity (secondary chemistry—glucosinolate profile) or genetic similarity (sequence of the chloroplast gene ndhF) using two methods—simple correlations or strengths of association between feeding by each species, and dendrograms based on either glucosinolates or ndhF sequence (i.e., a phylogram). For comparison, we performed a similar test with the oligophagous Plutella xylostella (L.) (Lepidoptera: Plutellidae) using the same plant species. We found using either method that phenotypic similarity was more strongly associated with feeding intensity by C. cardariae than genetic similarity. In contrast, neither genetic nor phenotypic similarity was significantly associated with feeding intensity on the test species by P. xylostella. The result indicates that phenotypic traits can be more reliable indicators of the feeding preference of a specialist than phylogenetic relatedness of its potential hosts. This has implications for the evolution and maintenance of host ranges and host specialization in phytophagous insects. It also has implications for identifying plant species at risk of nontarget attack by potential weed biological control agents and hence the approach to prerelease testing.

We investigated the genetic diversity and origins of a long-term cultivar. Dyer’s woad has been used as a dye source for at least eight centuries in Eurasia. It was introduced to eastern USA in the 1600s, and is now considered invasive in the western USA. Our analysis of plants from the USA and Eurasia suggests that there are two distinct invasions in western USA that most likely originate from Switzerland, Ukraine and Germany. This information assists in finding effective biological control agents, and continued combination of ecological and molecular data helps bring us closer to sustainable management of plant invasions., Population structure and genetic diversity of invasions are the result of evolutionary processes such as natural selection, drift and founding events. Some invasions are also molded by specific human activities such as selection for cultivars and intentional introduction of desired phenotypes, which can lead to low genetic diversity in the resulting invasion. We investigated the population structure, diversity and origins of a species with both accidental and intentional introduction histories, as well as long-term selection as a cultivar. Dyer’s woad (Isatis tinctoria; Brassicaceae) has been used as a dye source for at least eight centuries in Eurasia, was introduced to eastern USA in the 1600s, and is now considered invasive in the western USA. Our analyses of amplified fragment length polymorphisms (AFLPs) from 645 plants from the USA and Eurasia did not find significantly lower gene diversity (Hj) in the invaded compared to the native range. This suggests that even though the species was under cultivation for many centuries, human selection of plants may not have had a strong influence on diversity in the invasion. We did find significantly lower genetic differentiation (Fst) in the invasive range but our results still suggested that there are two distinct invasions in the western USA. Our data suggest that these invasions most likely originated from Switzerland, Ukraine and Germany, which correlates with initial biological control agent survey findings. Genetic information on population structure, diversity and origins assists in efforts to control invasive species, and continued combination of ecological and molecular analyses will help bring us closer to sustainable management of plant invasions.

International audience; The root-galling weevil, Ceutorhynchus assimilis Paykull (Coleoptera, Curculionidae), has been selected as one of the candidates to control Lepidium draba L. (Brassicaceae), a highly invasive weed in western North America. Originally been described as oligophagous, also attacking crop species, previous studies indicated that a specific host race to L. draba exists in C. assimilis. We therefore explored the evolutionary history and phylogeographic structure of this weevil by sampling individuals from 67 populations, spanning 12 countries and five different host plant species including L. draba. To explore the genetic diversity of C. assimilis, we analyzed the COI gene sequences of 458 individuals. Analysis revealed three distinct evolutionary lineages, one of which, the so-called Lepidium host race, was only found on L. draba and appears to occur in a restricted geographic area, ranging between northern Spain and northern Italy. These results allow us to targeting sites for collection of the Lepidium host race and justify the prioritization of C. assimilis Lepidium host race as a candidate for the L. draba biological control.

Following preliminary host-specificity testing Septori lepidii Desm. was recently proposed as a potentially important biological control agent for invasive Lepidium species in North America. Conversely, a previous, unpublished assessment of S. lepidii for biocontrol of Lepidium latifolium found the pathogen to be unsuitable due to infection of the American native Lepidium huberi.

We differentiate between the success of a classical biological control programme and its impact; the former addressing the completed implementation of the steps of a biological control programme, and the anticipated reduction of the target pest, and the latter addressing the societal and environmental benefits of control of the target pest. We provide ten case studies in which CABI has played a role to illustrate aspects of success and impact for biological control programmes against insects pests and weeds: cassava mealybug ( Phenacoccus manihoti ), mango mealybug ( Rastrococcus invadens ), pink hibiscus mealybug ( Maconellicoccus hirsutus ), orthezia bug ( Insignorthezia insignis ), brown peach aphid ( Pterochloroides persicae ), banana skipper ( Erionota torus ), black sage ( Varronia curassavica ), rubber vine ( Cryptostegia grandiflora ), leafy spurge ( Euphorbia esula ) and water hyacinth ( Eichhornia crassipes ). In light of these we discuss the assessment of success and impact of biological control programmes, why these aspects are often not adequately addressed, how they might be retroactively addressed and the implications for donor-funding of biological control programmes for developing countries.

Species may become invasive after introduction to a new range because phenotypic traits pre-adapt them to spread and become dominant. In addition, adaptation to novel selection pressures in the introduced range may further increase their potential to become invasive. The diploid Leucanthemum vulgare and the tetraploid L. ircutianum are native to Eurasia and have been introduced to North America, but only L. vulgare has become invasive. To investigate whether phenotypic differences between the two species in Eurasia could explain the higher abundance of L. vulgare in North America and whether rapid evolution in the introduced range may have contributed to its invasion success, we grew 20 L. vulgare and 21 L. ircutianum populations from Eurasia and 21 L. vulgare populations from North America under standardized conditions and recorded performance and functional traits. In addition, we recorded morphological traits to investigate whether the two closely related species can be clearly distinguished by morphological means and to what extent morphological traits have changed in L. vulgare post-introduction. We found pronounced phenotypic differences between L. vulgare and L. ircutianum from the native range as well as between L. vulgare from the native and introduced ranges. The two species differed significantly in morphology but only moderately in functional or performance traits that could have explained the higher invasion success of L. vulgare in North America. In contrast, leaf morphology was similar between L. vulgare from the native and introduced range, but plants from North America flowered later, were larger and had more and larger flower heads than those from Eurasia. In summary, we found litte evidence that specific traits of L. vulgare may have pre-adapted this species to become more invasive than L. ircutianum, but our results indicate that rapid evolution in the introduced range likely contributed to the invasion success of L. vulgare.

Perennial pepperweed is an invasive plant species in North America, native to temperate Eurasia and northern Africa. Effective biological control depends upon correct taxonomic identification. Therefore, we investigated morphological and genetic data (cpDNA sequences and amplified fragment length polymorphisms [AFLP]) in its native range, where the species is at times treated as multiple taxa (L. latifolium, L. affineandL. obtusum). We also analyzed genetic data to determine the number and distribution of haplotypes and genotypes in the invaded range. Using Bayesian analysis, we found three clusters of AFLP genotypes in the native range, but little correlation between these clusters and morphological characters used to distinguish taxa. Also, we found combinations of morphological character states within many native range plants that are incompatible with current species descriptions, offering no support for splittingL. latifoliumsensu lato into three species. In North America 97% of the genetic variation was among populations and there were only eight AFLP genotypes in 288 plants, suggesting few introductions or a severe bottleneck, and little or no creation of new genotypes since introduction. We found plants in the native range that are genetically similar (88 to 99%) to six of the eight invasive AFLP genotypes, suggesting that Kazakhstan and China are origins for much of the North American invasion.

Polyploidy is considered to be a major source of genetic diversity in plants. Genome duplication has been shown repeatedly to be associated with changes in biotic interactions, but little is known about whether species traits such as herbivore resistance consistently change with increasing ploidy level among closely related plant species. We tested whether larval survival and performance of the specialist root-mining moth Dichrorampha aeratana are influenced by the ploidy level of plant species in the genus Leucanthemum by experimentally infesting 16 different taxa with ploidy levels ranging from diploid to dodecaploid. We found that survival of D. aeratana larvae consistently decreased with increasing ploidy level, irrespective of whether phylogenetic distance among taxa was taken into account or not. The mass of larvae and the proportion of adults emerging from last-instar larvae, however, did not consistently change with increasing ploidy level. Root biomass and dry matter content of the Leucanthemum taxa were neither correlated with ploidy level nor correlated with survival or mass of D. aeratana larvae. In summary, our results provide evidence that in the genus Leucanthemum, resistance to the specialist root herbivore D. aeratana consistently increases with increasing plant ploidy level, but it remains unclear which characteristics associated with polyploidy account for the higher herbivore resistance.

The mechanism causing breaks in the radial surface brightness distribution of spiral galaxies is not yet well known. Despite theoretical efforts, there is not a unique explanation for these features and the observational results are not conclusive. In an attempt to address this problem, we have selected a sample of 34 highly inclined spiral galaxies present both in the Sloan Digital Sky Survey and in the Spitzer Survey of Stellar Structure in Galaxies. We have measured the surface brightness profiles in the five Sloan optical bands and in the 3.6$\mu m$ Spitzer band. We have also calculated the color and stellar surface mass density profiles using the available photometric information, finding two differentiated features: an innermost break radius at distances of $\sim 8 \pm 1$ kpc [$0.77 \pm 0.06$ $R_{25}$] and a second characteristic radius, or truncation radius, close to the outermost optical extent ($\sim 14 \pm 2$ kpc [$1.09 \pm 0.05$ $R_{25}$]) of the galaxy. We propose in this work that the breaks might be a phenomena related to a threshold in the star formation, while truncations are more likely a real drop in the stellar mass density of the disk associated with the maximum angular momentum of the stars.

A combination of observational and experimental methods, in both the laboratory and field, were used to assess niche partitioning between Ceutorhynchus alliariae Brisout and C. roberti Gyllenhal (Coleoptera: Curculionidae), two coexisting shoot-boring weevils on garlic mustard, Alliaria petiolata (M. Bieb.) Cavara and Grande (Brassicaceae). We compared their morphology, oviposition behavior, larval development, distribution, abundance, and attack rates in their sympatric range, and of C. alliariae when found alone and in sympatry with C. roberti. Results indicate only very small differences in the fundamental niches of the two species. Comparison of C. alliariae in the range it occurs alone with the range where it co-occurs with C. roberti revealed some evidence for competition between the two species, i.e., attack levels of C. alliariae were reduced in areas where it co-occurred with C. roberti. However, the study showed no character displacement in regard to adult size or shoot choice of C. alliariae and we found no indication for superiority of either of the two species. Clearly, manipulative experiments would be necessary to unambiguously test for competition between the two species. Our results, based on a subset of niche dimensions known to be important in other systems, suggest that C. alliariae and C. roberti may present one of the rare cases, in which niche differentiation is not the main mechanism underlying coexistence.

Taking advantage of the sensitivity and angular resolution of the Herschel Space Observatory at far-infrared and submm wavelengths, we aim to characterize the physical properties of cold dust within nearby galaxies and study the robustness of the parameters we derive using different modified blackbody models. For a pilot subsample of the KINGFISH program, we perform 2 temperature fits of the Spitzer and Herschel photometric data (24 to 500um), with a warm and a cold component, globally and in each resolution element.At global scales, we observe ranges of values for beta_c(0.8 to 2.5) and Tc(19.1 to 25.1K).We compute maps of our parameters with beta fixed or free to test the robustness of the temperature and dust surface density maps we deduce. When the emissivity is fixed, we observe temperature gradients as a function of radius.When the emissivity is fitted as a free parameter, barred galaxies tend to have uniform fitted emissivities.Gathering resolved elements in a Tc-beta_c diagram underlines an anti-correlation between the two parameters.It remains difficult to assess whether the dominant effect is the physics of dust grains, noise, or mixing along the line of sight and in the beam. We finally observe in both cases that the dust column density peaks in central regions of galaxies and bar ends (coinciding with molecular gas density enhancements usually found in these locations).We also quantify how the total dust mass varies with our assumptions about the emissivity index as well as the influence of the wavelength coverage used in the fits. We show that modified blackbody fits using a shallow emissivity (beta_c < 2.0) lead to significantly lower dust masses compared to the beta_c < 2.0 case, with dust masses lower by up to 50% if beta_c=1.5 for instance.The working resolution affects our total dust mass estimates: masses increase from global fits to spatially-resolved fits.

Invasive plants are expected to perform better and consequently be more abundant in their introduced compared to their native ranges. However, few studies have simultaneously compared plant and population traits along with biotic and abiotic environmental parameters for invasive and native plant populations. We compared 17 native Eastern European, 14 expanded Western European and 31 introduced US populations of the invasive Lepidium draba over 2 years. Most parameters were similar between the two European ranges, but differed for the US. Density, cover, and biomass of L. draba were greater in the US while cover of other vegetation was lower. Bare-ground and litter cover were greater for US populations in 1 year, as was L. draba shoot height and seed output. Availability of labile soil nitrogen was also greater in the US range. Endophagous shoot herbivory was greater in Western Europe compared to the US in 1 year. As expected, specialist herbivores were only found in Europe. Differences between ranges were not explained by varying environmental conditions (climate, altitude and latitude). In summary our results indicate that lower interspecific competition, higher resource availability and the lack of specialist natural enemies may all contribute to the increased performance of L. draba in its introduced US range. Additionally, L. draba is well adapted to disturbance events, which may further benefit its competitiveness at degraded sites. In general our results were consistent between years, which reinforces their validity. However, some of the differences were only significant in one of the 2 years, which, on the other hand, emphasizes the importance to ideally conduct biogeographic comparisons over multiple years.

Perennial pepperweed (Lepidium latifolium L.) is a Eurasian plant species that is invasive in North America. The invasion often forms large, dense monocultural stands. We investigated the genetic diversity along transects in dense populations in the western USA using Amplified Fragment Length Polymorphisms. We also analyzed transect collections from the native Eurasian range for comparison. In addition, we conducted crossing studies to determine possible modes of seed production (sexual outcrossing vs. self-fertilization vs. apomixis). In our study of seed production we determined that self-fertilization and outcrossing both produce germinable seed in perennial pepperweed. Genetic diversity in the USA was unexpectedly low, with only three genotypes in 388 plants, and those three had genetic similarity of ≥98%. Up to 97% of the plants from Turkey and Russia transects were unique genotypes, while

The KINGFISH project (Key Insights on Nearby Galaxies: a Far-Infrared Survey with Herschel) is an imaging and spectroscopic survey of 61 nearby (d < 30 Mpc) galaxies, chosen to cover a wide range of galaxy properties and local interstellar medium (ISM) environments found in the nearby Universe. Its broad goals are to characterize the ISM of present-day galaxies, the heating and cooling of their gaseous and dust components, and to better understand the physical processes linking star formation and the ISM. KINGFISH is a direct descendant of the Spitzer Infrared Nearby Galaxies Survey (SINGS), which produced complete Spitzer imaging and spectroscopic mapping and a comprehensive set of multi-wavelength ancillary observations for the sample. The Herschel imaging consists of complete maps for the galaxies at 70, 100, 160, 250, 350, and 500 microns. The spectal line imaging of the principal atomic ISM cooling lines ([OI]63um, [OIII]88um, [NII]122,205um, and [CII]158um) covers the subregions in the centers and disks that already have been mapped in the mid-infrared with Spitzer. The KINGFISH and SINGS multi-wavelength datasets combined provide panchromatic mapping of the galaxies sufficient to resolve individual star-forming regions, and tracing the important heating and cooling channels of the ISM, across a wide range of local extragalactic ISM environments. This paper summarizes the scientific strategy for KINGFISH, the properties of the galaxy sample, the observing strategy, and data processing and products. It also presents a combined Spitzer and Herschel image atlas for the KINGFISH galaxies, covering the wavelength range 3.6 -- 500 microns. All imaging and spectroscopy data products will be released to the Herschel user generated product archives.

Gerber E, Schaffner U, Gassmann A, Hinz HL, Seier M & Muller-Scharer H (2011). Prospects for biological control of Ambrosia artemisiifolia in Europe: learning from the past. Weed Research51, 559–573. Summary The recent invasion by Ambrosia artemisiifolia (common ragweed) has, like no other plant, raised the awareness of invasive plants in Europe. The main concerns regarding this plant are that it produces a large amount of highly allergenic pollen that causes high rates of sensitisation among humans, but also A. artemisiifolia is increasingly becoming a major weed in agriculture. Recently, chemical and mechanical control methods have been developed and partially implemented in Europe, but sustainable control strategies to mitigate its spread into areas not yet invaded and to reduce its abundance in badly infested areas are lacking. One management tool, not yet implemented in Europe but successfully applied in Australia, is biological control. Almost all natural enemies that have colonised A. artemisiifolia in Europe are polyphagous and cause little damage, rendering them unsuitable for a system management approach. Two fungal pathogens have been reported to adversely impact A. artemisiifolia in the introduced range, but their biology makes them unsuitable for mass production and application as a mycoherbicide. In the native range of A. artemisiifolia, on the other hand, a number of herbivores and pathogens associated with this plant have a very narrow host range and reduce pollen and seed production, the stage most sensitive for long-term population management of this winter annual. We discuss and propose a prioritisation of these biological control candidates for a classical or inundative biological control approach against A. artemisiifolia in Europe, capitalising on past experiences from North America, Asia and Australia.

The Eurasian perennial mustard, hoary cress, Cardaria draba (Brassicaceae), is an invasive weed in western North America that can displace native plants and other desirable forage species in pastures and rangelands. This study investigated the competitive ability of 11 grasses representing nine species in the genera Festuca and Poa from either North America (NA) or Europe (EU) against hoary cress. Hoary cress was grown alone and with four different grass densities under controlled conditions with ample water and nutrient supply, typical for riparian and disturbed habitats, in which hoary cress infestations are commonly found. Of the five Festuca grasses tested, only Schedonorus phoenix (= F. arundinacea) decreased hoary cress biomass. Four of the six Poa grasses tested decreased hoary cress biomass and were ranked by decreasing competitive effects as follows: P. annua > P. compressa (EU) > P. pratensis (EU) > P. compressa (NA). The most competitive grass species also experienced higher intraspecific competition. Within both grass genera, Eurasian species were more competitive against hoary cress than their North American congeners, which suggests that hoary cress establishment may be facilitated by lower biotic resistance in the invaded range. Regardless of origin, sod-forming Poa species were competitive at low densities, while Festuca species only had significant effects at high densities if at all. Based on our results we recommend the use of Poa species for restoration of riparian and disturbed sites following the control of hoary cress infestations to restrict recolonization.

Introduced weeds are hypothesized to be invasive in their exotic ranges due to release from natural enemies. Cirsium arvense (Californian, Canada, or creeping thistle) is a weed of Eurasian origin that was inadvertently introduced to New Zealand (NZ), where it is presently one of the worst invasive weeds. We tested the ‘enemy release hypothesis’ (ERH) by establishing natural enemy exclusion plots in both the native (Europe) and introduced (NZ) ranges of C. arvense. We followed the development and fate of individually labelled shoots and recorded recruitment of new shoots into the population over two years. Natural enemy exclusion had minimal impact on shoot height and relative growth rate in either range. However, natural enemies did have a significant effect on shoot population growth and development in the native range, supporting the ERH. In year one, exclusion of insect herbivores increased mean population growth by 2.1–3.6 shoots m−2, and in year two exclusion of pathogens increased mean population growth by 2.7–4.1 shoots m−2. Exclusion of insect herbivores in the native range also increased the probability of shoots developing from the budding to the reproductive growth stage by 4.0× in the first year, and 13.4× in the second year; but exclusion of pathogens had no effect on shoot development in either year. In accordance with the ERH, exclusion of insect herbivores and pathogens did not benefit shoot development or population growth in the introduced range. In either range, we found no evidence for an additive benefit of dual exclusion of insects and pathogens, and in no case was there an interaction between insect and pathogen exclusion. This study further demonstrates the value of conducting manipulative experiments in the native and introduced ranges of an invasive plant to elucidate invasion mechanisms.

The Spitzer Survey of Stellar Structure in Galaxies S^4G is an Exploration Science Legacy Program approved for the Spitzer post-cryogenic mission. It is a volume-, magnitude-, and size-limited (d 30 degrees, m_(Bcorr) 1') survey of 2,331 galaxies using IRAC at 3.6 and 4.5 microns. Each galaxy is observed for 240 s and mapped to > 1.5 x D25. The final mosaicked images have a typical 1 sigma rms noise level of 0.0072 and 0.0093 MJy / sr at 3.6 and 4.5 microns, respectively. Our azimuthally-averaged surface brightness profile typically traces isophotes at mu_3.6 (AB) (1 sigma) ~ 27 mag arcsec^-2, equivalent to a stellar mass surface density of ~ 1 Msun pc^-2. S^4G thus provides an unprecedented data set for the study of the distribution of mass and stellar structures in the local Universe. This paper introduces the survey, the data analysis pipeline and measurements for a first set of galaxies, observed in both the cryogenic and warm mission phase of Spitzer. For every galaxy we tabulate the galaxy diameter, position angle, axial ratio, inclination at mu_3.6 (AB) = 25.5 and 26.5 mag arcsec^-2 (equivalent to ~ mu_B (AB) =27.2 and 28.2 mag arcsec^-2, respectively). These measurements will form the initial S^4G catalog of galaxy properties. We also measure the total magnitude and the azimuthally-averaged radial profiles of ellipticity, position angle, surface brightness and color. Finally, we deconstruct each galaxy using GALFIT into its main constituent stellar components: the bulge/spheroid, disk, bar, and nuclear point source, where necessary. Together these data products will provide a comprehensive and definitive catalog of stellar structures, mass and properties of galaxies in the nearby Universe.