Studies on a sex pheromone in Stegobium paniceum (L.) (Coleoptera; Anobiidae)

The sex pheromone system of Stegobium paniceum (L.) was studied in the laboratory by means of live female assay experiments as well as extraction of the pheromone from females using solvent and volatilisation techniques. Female beetles were shown to attract only males, which were themselves attractive to neither sex. Female Stegobium were capable of controlled pheromone emission even when body content levels were high. Newly eclosed females contained small quantities of pheromone which reached maximum levels in 6 to 9-day-old insects. Very little emission occurred until females were 2.5-3.5 days old, after which maximum emission rates were reached rapidly between days 3 and 4, the age at which the first mature oocytes were found in the calyx of female ovaries. A series of dilutions of solvent pheromone extracts were bioassayed with males and a theoretical minimum threshold level of response extrapolated to 0.0004 female equivalents. By comparison with a "wild" strain of Stegobium it was suggested that mass rearing over a long period increased male sensitivity to the pheromone but lengthened the period necessary to reach maximum response levels after adult emergence. Mating slightly reduced female pheromone content, but pheromone emission fluctuated markedly after mating for reasons not fully understood. The number of eggs laid per female increased from about 1.5 to over 40 if copulation occurred. Male presence during oviposition increased the percentage of females producing eggs but decreased the number of eggs laid per female of those laying. This reflects decreased fertility of females with age. The antennal sensilla of Stegobium were surveyed by means of light and scanning electron microscopy. The main types present were trichoidea, basiconica, chaetica and coeloconica, and there was no apparent sexual dimorphism of sensilla numbers or distribution. Male antennectomy completely inhibited sex pheromone response and progressive removal of club segments increasingly diminished male response intensity

Integrating adverse effect analysis into environmental risk assessment for exotic generalist arthropod biological control agents: a three-tiered framework

Environmental risk assessments (ERAs) are required before utilizing exotic arthropods for biological control (BC). Present ERAs focus on exposure analysis (host/prey range) and have resulted in approval of many specialist exotic biological control agents (BCA). In comparison to specialists, generalist arthropod BCAs (GABCAs) have been considered inherently risky and less used in classical biological control. To safely consider exotic GABCAs, an ERA must include methods for the analysis of potential effects. A panel of 47 experts from 14 countries discussed, in six online forums over 12 months, scientific criteria for an ERA for exotic GABCAs. Using four case studies, a three-tiered ERA comprising Scoping, Screening and Definitive Assessments was developed. The ERA is primarily based on expert consultation, with decision processes in each tier that lead to the approval of the petition or the subsequent tier. In the Scoping Assessment, likelihood of establishment (for augmentative BC), and potential effect(s) are qualitatively assessed. If risks are identified, the Screening Assessment is conducted, in which 19 categories of effects (adverse and beneficial) are quantified. If a risk exceeds the proposed risk threshold in any of these categories, the analysis moves to the Definitive Assessment to identify potential non-target species in the respective category(ies). When at least one potential non-target species is at significant risk, long-term and indirect ecosystem risks must be quantified with actual data or the petition for release can be dismissed or withdrawn. The proposed ERA should contribute to the development of safe pathways for the use of low risk GABCAs

Hyperoxemia and excess oxygen use in early acute respiratory distress syndrome : Insights from the LUNG SAFE study

Publisher Copyright: © 2020 The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Background: Concerns exist regarding the prevalence and impact of unnecessary oxygen use in patients with acute respiratory distress syndrome (ARDS). We examined this issue in patients with ARDS enrolled in the Large observational study to UNderstand the Global impact of Severe Acute respiratory FailurE (LUNG SAFE) study. Methods: In this secondary analysis of the LUNG SAFE study, we wished to determine the prevalence and the outcomes associated with hyperoxemia on day 1, sustained hyperoxemia, and excessive oxygen use in patients with early ARDS. Patients who fulfilled criteria of ARDS on day 1 and day 2 of acute hypoxemic respiratory failure were categorized based on the presence of hyperoxemia (PaO2 > 100 mmHg) on day 1, sustained (i.e., present on day 1 and day 2) hyperoxemia, or excessive oxygen use (FIO2 ≥ 0.60 during hyperoxemia). Results: Of 2005 patients that met the inclusion criteria, 131 (6.5%) were hypoxemic (PaO2 < 55 mmHg), 607 (30%) had hyperoxemia on day 1, and 250 (12%) had sustained hyperoxemia. Excess FIO2 use occurred in 400 (66%) out of 607 patients with hyperoxemia. Excess FIO2 use decreased from day 1 to day 2 of ARDS, with most hyperoxemic patients on day 2 receiving relatively low FIO2. Multivariate analyses found no independent relationship between day 1 hyperoxemia, sustained hyperoxemia, or excess FIO2 use and adverse clinical outcomes. Mortality was 42% in patients with excess FIO2 use, compared to 39% in a propensity-matched sample of normoxemic (PaO2 55-100 mmHg) patients (P = 0.47). Conclusions: Hyperoxemia and excess oxygen use are both prevalent in early ARDS but are most often non-sustained. No relationship was found between hyperoxemia or excessive oxygen use and patient outcome in this cohort. Trial registration: LUNG-SAFE is registered with ClinicalTrials.gov, NCT02010073publishersversionPeer reviewe

Weevils as Targets for Biological Control, and the Importance of Taxonomy and Phylogeny for Efficacy and Biosafety

Curculionidae are a large mainly herbivorous family of beetles, some of which have become crop pests. Classical biological control has been attempted for about 38 species in 19 genera, and at least moderate success has been achieved in 31 % of cases. Only two weevil species have been considered to be completely controlled by a biological control agent. Success depends upon accurately matching natural enemies with their hosts, and hence taxonomy and phylogeny play a critical role. These factors are discussed and illustrated with two case studies: the introduction of the braconid parasitoid Mictroctonus aethiopoides into New Zealand for biological control of the lucerne pest Sitona discoideus, a case of complex phylogenetic relationships that challenged the prediction of potential non-target hosts, and the use of a mymarid egg parasitoid, Anaphes nitens, to control species of the eucalypt weevil genus Gonipterus, which involves failure to match up parasitoids with the right target amongst a complex of very closely related species. We discuss the increasing importance of molecular methods to support biological control programmes and the essential role of these emerging technologies for improving our understanding of this very large and complex family

Beetle (Coleoptera) communities inside and outside the pest-resistant fencing of a New Zealand ecosanctuary

The ecological impacts of invasive mammals are widely documented around the world. In New Zealand, fencing designed to exclude non-native mammals is used for conservation and restoration efforts. The Orokonui Ecosanctuary is a 307-hectare coastal Otago reserve (Dunedin, New Zealand) that is surrounded by mammal-exclusion fencing. The goal of the present study was to investigate how excluding mammals and including (native) animals inside the Orokonui Ecosanctuary fence has influenced ground- and litter-dwelling beetle (Coleoptera) abundance, diversity, and community composition. We hypothesised that beetle abundance, diversity, and community composition would be different whether the beetles sampled were from sites inside the fence or outside the fence. Beetles were extracted from the litter and soil of six sites (three inside, three outside) two times (once in winter, once in summer). The abundance, diversity, species composition, size distribution, and trophic guild distribution of beetles inside and outside the fence and between seasons were compared. Our results suggest that sites inside the fence harbour a greater abundance and diversity of beetles. We found a high abundance of native beetles both inside and outside the Orokonui Ecosanctuary’s fence. Further research may find evidence that the fenced sanctuary is providing a ‘halo effect’ whereby native beetles thriving within the Orokonui Ecosanctuary are spreading out into the surrounding landscape and also outcompeting introduced beetles.</p

Big and aerial invaders:dominance of exotic spiders in burned New Zealand tussock grasslands

As post-disturbance community response depends on the characteristics of the ecosystem and the species composition, so does the invasion of exotic species rely on their suitability to the new environment. Here, we test two hypotheses: exotic spider species dominate the community after burning; and two traits are prevalent for their colonisation ability: ballooning and body size, the latter being correlated with their dispersal ability. We established spring burn, summer burn and unburned experimental plots in a New Zealand tussock grassland area and collected annual samples 3 and 4 years before and after the burning, respectively. Exotic spider abundance increased in the two burn treatments, driven by an increase in Linyphiidae. Indicator analysis showed that exotic and native species characterised burned and unburned plots, respectively. Generalised linear mixed-effects models indicated that ballooning had a positive effect on the post-burning establishment (density) of spiders in summer burn plots but not in spring plots. Body size had a positive effect on colonisation and establishment. The ability to balloon may partly explain the dominance of exotic Linyphiidae species. Larger spiders are better at moving into and colonising burned sites probably because of their ability to travel longer distances over land. Native species showed a low resilience to burning, and although confirmation requires longer-term data, our findings suggest that frequent fires could cause long lasting damage to the native spider fauna of tussock grasslands, and we propose limiting the use of fire to essential situations

Will the Convention on Biological Diversity put an end to biological control?

Will the Convention on Biological Diversity put an end to biological control? Under the Convention on Biological Diversity countries have sovereign rights over their genetic resources. Agreements governing the access to these resources and the sharing of the benefits arising from their use need to be established between involved parties. This also applies to species collected for potential use in biological control. Recent applications of access and benefit sharing principles have already made it difficult or impossible to collect and export natural enemies for biological control research in several countries. If such an approach is widely applied it would impede this very successful and environmentally safe pest management method based on the use of biological diversity. The International Organization for Biological Control of Noxious Animals and Plants has, therefore, created the "Commission on Biological Control and Access and Benefit Sharing". This commission is carrying out national and international activities to make clear how a benefit sharing regime might seriously frustrate the future of biological control. In addition, the IOBC Commission members published information on current regulations and perceptions concerning exploration for natural enemies and drafted some 30 case studies selected to illustrate a variety of points relevant to access and benefit sharing. In this article, we summarize our concern about the effects of access and benefit sharing systems on the future of biological control