Lethal Effects of the Non-native Invasive Shrub Amur Honeysuckle (Lonicera maackii) on a Model Aquatic Organism (Hyalella azteca)

The invasive plant Lonicera maackii (Amur honeysuckle) has had a variety of ecological effects as it continues to spread through the eastern United States including the loss of plant biodiversity and alterations in ecosystem function in forests. Streams meander through many forests where Amur honeysuckle is present and recent evidence suggests that this terrestrial invasion has consequences for stream biology. Leaves of Amur honeysuckle have been shown to have strong negative effects on terrestrial insects and we hypothesized that these negative effects may also occur in aquatic macroinvertebrates. In this set of experiments we used a sequence of microcosm assays to assess the influence of Amur honeysuckle leachate on the macroinvertebrate Hyalella azteca, which is a standard “model” aquatic organism to toxicity assessment In the lab, H. azteca were exposed to riparian honeysuckle leaf leachate (made by soaking 10 g leaves in 100 mL dechlorinated water for 24 h) in 48 h acute, static toxicity tests. This was repeated throughout the growing season. When exposed to an Amur honeysuckle leachate dilution series (6.25%, 12.5%, 25%, 50%, 100%), H. azteca survival was significantly decreased in all dilutions in the spring and fall trials. However, the summer trials showed no significant decrease in survival in nearly all the dilutions. These results suggest (a) strong toxic effects of Amur honeysuckle foliage on a model aquatic organism that (b) varies throughout the year, potentially in relationship to biochemical changes associated with phenology. Future experiments regarding the chemical composition and toxicity of these leaves should be mindful of the season in which the leaves are gathered. This study supports the importance of management of Amur honeysuckle in headwater stream riparian zones which are particularly vulnerable to perturbations and are increasingly a focus of conservation

Lethal Effects of Leaf Leachate from the Non-Native Invasive Shrub Amur Honeysuckle (Lonicera maackii) on a Model Aquatic Organism (Hyalella azteca)

The invasive shrub Lonicera maackii (Amur honeysuckle) is a problematic species in the eastern United States and there is growing evidence that materials from this species have toxic effects on some organisms. We used a sequence of microcosm bioassays to assess the influence of L. maackii leaf leachate on the macroinvertebrate Hyalella azteca, which is a standard aquatic organism for toxicity assessment. In a laboratory setting, H. azteca were exposed to a leaf leachate dilution series (6.25%, 12.5%, 25%, 50%, 100%) in 48-h toxicity tests. This was repeated throughout the growing season to assess the potential for changes in leaf toxicity due to phenology. Strong toxic effects were found when H. azteca was exposed to a L. maackii leachate from autumn (P \u3c 0.05) and, in fact, all organisms died when exposed to any level of concentration in most trials. Mean percent survival also decreased significantly in all dilutions in the spring (P \u3c 0.05 for all treatments); however, little toxicity was detected in growing season trials. These results suggest (a) strong toxic effects of L. maackii foliage on a model aquatic organism that (b) varies throughout the year, potentially in relationship to biochemical changes associated with phenology

Leaf phenology and freeze tolerance of the invasive tree Pyrus calleryana (Roseaceae) and potential native competitors

Pyrus calleryana is one of the most problematic invasive species in the eastern United States. The mechanisms that enable Py. calleryana to establish and outcompete native plants are not fully understood but likely include a profile of advantageous traits. Extended leaf phenology is a characteristic noted in many woody invasive plants. Leaf phenology of Py. calleryana and two native woody species, Populus deltoides and Platanus occidentalis, was observed in natural areas near Dayton, OH from December 2019 to November 2020. A frost event in May also gave us the serendipitous opportunity to assess frost tolerance of these species. We found that Py. calleryana began leafing out almost a month before its native competitors in the spring and kept its leaves on significantly longer than both Po. deltoides and Pl. occidentalis throughout the fall. After the frost event, almost every leaf on Pl. occidentalis died and almost 70% of the leaves on Po. deltoides were damaged; however, Py. calleryana exhibited damage on only 6% of its leaves. Our study suggests that Py. calleryana has a nearly 1-mo advantage in leaf phenology in both spring and fall, and much greater frost tolerance, as compared with native species. These attributes likely contribute to its capacity to outcompete native trees in early successional habitats

Lethal and Sublethal Effects of Novel Terrestrial Subsidies from an Invasive Shrub (Lonicera maackii) on Stream Macroinvertebrates

The biology of headwater streams is intimately linked to that of the surrounding terrestrial environment through organic matter subsidies. Lonicera maackii, an invasive shrub that is becoming abundant in headwater stream riparian areas, deposits substantial quantities of organic matter into the aquatic system. This organic material has allelopathic effects on terrestrial plants and insects, and a growing body of work suggests strong connections between L. maackii invasion and aquatic biota. Lonicera maackii deposits fruit and flowers in quantities and timings that are unique, and we tested the hypothesis that these subsidies would negatively affect survival and growth of laboratory-cultured Hyalella azteca and field-collected Anthopotamus verticis and Allocapnia spp. Invertebrates were exposed to a gradient of fruit (reference sediment + 0, 0.31, 0.62, 1.25, or 2.5 g dry mass [DM]) and flower (reference sediment + 0, 0.30, 0.60, 1.2, or 2.4 g DM) biomass in laboratory and field sediment exposure tests. Hyalella azteca survival was significantly reduced by exposure to L. maackii fruit in the laboratory and in the field exposures, and a negative effect was observed for A. verticis (p\u3c 0.05). Lonicera maackii flower biomass was associated with negative effects on survival of H. azteca in the field and laboratory exposures and of A. verticis in the laboratory exposure. During the laboratory exposures, dissolved O2 (DO) and pH were /L and 5.5, respectively. In the field exposures, DO and pH were comparable to stream conditions during fruit exposures, declining significantly with increasing flower biomass. Our results suggest that L. maackii fruit and flowers, novel subsidies in these systems, can negatively affect benthic organism survival and growth. Research focused on verifying this novel subsidy hypothesis for L. maackii and other species could enhance our understanding of invasion biology and terrestrial–aquatic linkages

The influence of riparian invasion by the terrestrial shrub Lonicera maackii on aquatic macroinvertebrates in temperate forest headwater streams

The ecology of headwater streams is tightly linked to the riparian zone through organic matter subsidies which are highly susceptible to alteration due to biological invasion. Lonicera maackii is a non-native shrub that is a highly successful invader of headwater stream riparian zones in the American Midwest. We assessed effects on benthic macroinvertebrates across a gradient of invasion intensity from references sites with minimal invasion to a site that had a very heavy invasion. Benthic macroinvertebrates were sampled throughout the year and compositional differences were assessed using Non-metric Multidimensional Scaling ordination, and by comparing the prevalence of sensitive (Ephemeroptera, Plectoptera, and Trichoptera: EPT) and tolerant (Chironomidae) macroinvertebrate taxa. We found strong evidence of variation among macroinvertebrate communities across the invasion gradient (ANOSIM R = 0.215, P = 0.004) and particularly strong separation between one of our reference sites with minimal invasion and the site with the heaviest invasion. Analysis of EPT taxa indicated a significant overall effect and pairwise comparisons indicated that the site with the heaviest invasion had the lowest percentage of sensitive taxa (P \u3c 0.05). Our analysis of chironomids did not yield a statistically discernable effect, although the pattern of the data suggest higher dominance in the site with the heaviest invasion. These stream-scale results bolster prior laboratory and field experiments and provide evidence that terrestrial invasion of L. maackiiimpacts the benthic community present in headwater streams. These results provide impetus to re-focus stream management recommendations to include practices that control invasive plants in riparian forests

2021 Taxonomic update of phylum Negarnaviricota (Riboviria: Orthornavirae), including the large orders Bunyavirales and Mononegavirales.

Correction to: 2021 Taxonomic update of phylum Negarnaviricota (Riboviria: Orthornavirae), including the large orders Bunyavirales and Mononegavirales. Archives of Virology (2021) 166:3567–3579. https://doi.org/10.1007/s00705-021-05266-wIn March 2021, following the annual International Committee on Taxonomy of Viruses (ICTV) ratification vote on newly proposed taxa, the phylum Negarnaviricota was amended and emended. The phylum was expanded by four families (Aliusviridae, Crepuscuviridae, Myriaviridae, and Natareviridae), three subfamilies (Alpharhabdovirinae, Betarhabdovirinae, and Gammarhabdovirinae), 42 genera, and 200 species. Thirty-nine species were renamed and/or moved and seven species were abolished. This article presents the updated taxonomy of Negarnaviricota as now accepted by the ICTV.This work was supported in part through Laulima Government Solutions, LLC prime contract with the US National Institute of Allergy and Infectious Diseases (NIAID) under Contract No. HHSN272201800013C. J.H.K. performed this work as an employee of Tunnell Government Services (TGS), a subcontractor of Laulima Government Solutions, LLC under Contract No. HHSN272201800013C. This work was also supported in part with federal funds from the National Cancer Institute (NCI), National Institutes of Health (NIH), under Contract No. 75N91019D00024, Task Order No. 75N91019F00130 to I.C., who was supported by the Clinical Monitoring Research Program Directorate, Frederick National Lab for Cancer Research. This work was also funded in part by Contract No. HSHQDC-15-C-00064 awarded by DHS S&T for the management and operation of The National Biodefense Analysis and Countermeasures Center, a federally funded research and development center operated by the Battelle National Biodefense Institute (V.W.); and NIH contract HHSN272201000040I/HHSN27200004/D04 and grant R24AI120942 (N.V., R.B.T.). S.S. acknowledges partial support from the Special Research Initiative of Mississippi Agricultural and Forestry Experiment Station (MAFES), Mississippi State University, and the National Institute of Food and Agriculture, US Department of Agriculture, Hatch Project 1021494. Part of this work was supported by the Francis Crick Institute which receives its core funding from Cancer Research UK (FC001030), the UK Medical Research Council (FC001030), and the Wellcome Trust (FC001030).S

Advances in structure elucidation of small molecules using mass spectrometry

The structural elucidation of small molecules using mass spectrometry plays an important role in modern life sciences and bioanalytical approaches. This review covers different soft and hard ionization techniques and figures of merit for modern mass spectrometers, such as mass resolving power, mass accuracy, isotopic abundance accuracy, accurate mass multiple-stage MS(n) capability, as well as hybrid mass spectrometric and orthogonal chromatographic approaches. The latter part discusses mass spectral data handling strategies, which includes background and noise subtraction, adduct formation and detection, charge state determination, accurate mass measurements, elemental composition determinations, and complex data-dependent setups with ion maps and ion trees. The importance of mass spectral library search algorithms for tandem mass spectra and multiple-stage MS(n) mass spectra as well as mass spectral tree libraries that combine multiple-stage mass spectra are outlined. The successive chapter discusses mass spectral fragmentation pathways, biotransformation reactions and drug metabolism studies, the mass spectral simulation and generation of in silico mass spectra, expert systems for mass spectral interpretation, and the use of computational chemistry to explain gas-phase phenomena. A single chapter discusses data handling for hyphenated approaches including mass spectral deconvolution for clean mass spectra, cheminformatics approaches and structure retention relationships, and retention index predictions for gas and liquid chromatography. The last section reviews the current state of electronic data sharing of mass spectra and discusses the importance of software development for the advancement of structure elucidation of small molecules

2021 Taxonomic update of phylum Negarnaviricota (Riboviria: Orthornavirae), including the large orders Bunyavirales and Mononegavirales.

In March 2021, following the annual International Committee on Taxonomy of Viruses (ICTV) ratification vote on newly proposed taxa, the phylum Negarnaviricota was amended and emended. The phylum was expanded by four families (Aliusviridae, Crepuscuviridae, Myriaviridae, and Natareviridae), three subfamilies (Alpharhabdovirinae, Betarhabdovirinae, and Gammarhabdovirinae), 42 genera, and 200 species. Thirty-nine species were renamed and/or moved and seven species were abolished. This article presents the updated taxonomy of Negarnaviricota as now accepted by the ICTV

Drivers of Larch Forest Regeneration in Siberia

The Arctic is warming at an alarming rate, a phenomenon which has been causing more frequent and severe wildfires in boreal forests. The Cajander larch (Larix cajanderi) forests of Siberia are particularly important because they cover an immense area of carbon-rich permafrost, one of the largest terrestrial carbon sinks in the world. The fate of this belowground carbon is intimately tied to the structure of these larch forests, so we seek to understand how changes in fire regimes may affect factors that drive seedling establishment. The first objective was to examine how stand structure relates to stand level seed production. Full tree cone counts were conducted on 125 trees from 17 similar-aged stands across a tree density gradient. The second objective was to evaluate the importance of microsites that favor larch establishment (deemed safe sites ), a concept that has been anecdotally recorded, but not rigorously studied in this ecosystem. We examined 15 Cajander larch stands in northeastern Siberia that had burned in the past 18 years. We analyzed the strength of seedling preference by comparing the percentage of seedlings that establish on safe sites to the percentage of the area that is occupied by safe sites.Results from objective 1 showed that medium and low density stands produce the most seeds per hectare. This pattern seems to reflect a release from competitive stress that limits cone production in the higher density stands (\u3e10,000 trees per hectare), while also showing that stands with very low tree density (\u3c500 trees per hectare) face diminishing returns of competition release as resources may be underutilized. This information may help predict future ecosystem structure because seed availability is likely the most important driver of forest regeneration post-fire. The results for objective 2 indicated that safe sites were indeed preferentially colonized by larch seedlings. The preference for safe sites was also much more variable in lowland/floodplain sites, which may be due to the differences in types of safe sites that are predominant in lowland versus upland sites. By synthesizing these results regarding seed production and seedling establishment, we can better predict the success of reforestation after wildfires which influence the future of climate feedback loops

Drivers of Larch Forest Regeneration in Siberia

The Arctic is warming at an alarming rate, a phenomenon which has been causing more frequent and severe wildfires in boreal forests. The Cajander larch (Larix cajanderi) forests of Siberia are particularly important because they cover an immense area of carbon-rich permafrost, one of the largest terrestrial carbon sinks in the world. The fate of this belowground carbon is intimately tied to the structure of these larch forests, so we seek to understand how changes in fire regimes may affect factors that drive seedling establishment. The first objective was to examine how stand structure relates to stand level seed production. Full tree cone counts were conducted on 125 trees from 17 similar-aged stands across a tree density gradient. The second objective was to evaluate the importance of microsites that favor larch establishment (deemed safe sites ), a concept that has been anecdotally recorded, but not rigorously studied in this ecosystem. We examined 15 Cajander larch stands in northeastern Siberia that had burned in the past 18 years. We analyzed the strength of seedling preference by comparing the percentage of seedlings that establish on safe sites to the percentage of the area that is occupied by safe sites.Results from objective 1 showed that medium and low density stands produce the most seeds per hectare. This pattern seems to reflect a release from competitive stress that limits cone production in the higher density stands (\u3e10,000 trees per hectare), while also showing that stands with very low tree density (\u3c500 trees per hectare) face diminishing returns of competition release as resources may be underutilized. This information may help predict future ecosystem structure because seed availability is likely the most important driver of forest regeneration post-fire. The results for objective 2 indicated that safe sites were indeed preferentially colonized by larch seedlings. The preference for safe sites was also much more variable in lowland/floodplain sites, which may be due to the differences in types of safe sites that are predominant in lowland versus upland sites. By synthesizing these results regarding seed production and seedling establishment, we can better predict the success of reforestation after wildfires which influence the future of climate feedback loops