Strategies for Biological Control of Invasive Insects

The most widely used of the various approaches to biological control of invasive insects is so-called “conventional” biological control, which consists in introducing natural enemies (parasitoids, predators or pathogens) that originate from the same region as the insect. This approach is particularly well-suited to controlling forest insects because they reduce the pest population directly and lastingly all over the invaded territory. In addition to providing a description of the various stages of a biological control programme, the presentation provided answers to questions often brought up about this type of biocontrol, concentrating particularly on forest tree and woody plant pests. Information supplied by two databases was presented: the BIOCAT2010 base that records all introductions of parasitoids and predators for the purpose of controlling the insects. Another base relating to the entomopathogens used against insects. Up to 2010, more than 6 000 introductions of parasitoids and predators were carried out, targeting 588 species of insects, achieving control over 172 of those insects. Approximately 55 % of these introductions targeted woody plant pests. The rate of establishment of the natural enemies and success rates were higher for woody plant pests than for other pests. The presentation compared the success rates under various production systems and for various groups of woody plants for different orders of insect pests and for different categories of natural enemies. Trends over time since the beginning of conventional biological control at the end of the 19th century were also presented, together with the economic benefits, the risks of the strategy and the measures implemented to limit the latter. Finally, the outlook and obstacles relating to future biocontrol practices in Europe were discussed

Steinernema bertusi n. sp. (Rhabditida : Steinernematidae), a new entomopathogenic nematode from South Africa

Two isolates of Steinernema bertusi n. sp. were separately recovered from Tito, Mpumalanga, and Port Edward, Kwa Zulu Natal, South Africa. In this paper, we describe the isolates as a new entomopathogenic nematode (EPN) species using molecular and morphological methodologies. The new species belongs to the cameroonense -clade, which consists of nematodes only isolated from the African continent. Steinernema bertusi n. sp. is characterised by having the longest infective juvenile (IJ) for this clade at 716 (628-814) μ m. The IJ is further characterised by a body diam. of 32 (28-36) μ m and the pattern for the arrangement of the lateral ridges from head to tail is 2, 4, 5, 4, 2. The first-generation male spicule and gubernaculum length is 82 (72-88) μ m and 63 (54-72) μ m, respectively. Only 25% of the second-generation males possess a mucron. The first-generation females of S. bertusi n. sp. have a slightly protruding vulva, with double-flapped epiptygmata and a mucron at the posterior end. The new EPN species is most closely related to S. sacchari and is the sixth species to be included in the cameroonense -clade.https://brill.com/view/journals/nemy/nemy-overview.xmlhj2020Forestry and Agricultural Biotechnology Institute (FABI)Zoology and Entomolog

Mechanisms behind differential white grub host susceptibility to entomopathogenic nematodes

Control of white grubs, the sporadic root-feeding larvae of scarabid beetles, is difficult due to their cryptic nature and resistance to chemical insecticides. Potential exists for the use of entomopathogenic nematodes (EPN) for such control. The successful infection of white grubs by EPN, however, is limited by the white grubs’ innate reduced susceptibility in form of behavioural, morphological and physiological defences. This study aimed to determine the different physiological defence mechanisms of white grubs against attack by EPN. The white grub species, Pegylis sommeri and Schizonycha affinis, which were previously found to have a low level of susceptibility to EPN, and Maladera sp. 4, which had previously shown a relative high level of susceptibility, were examined. The ability of the EPN to penetrate the white grubs and of the EPN symbiotic bacteria to grow inside the insect haemolymph, the encapsulation rates, as well as the nematode growth inside the insect haemolymph, were determined. The results showed that the ability of the nematodes to penetrate white grubs, the encapsulation rates and growth in the haemolymph varied between EPN and white grub species. The different species of the EPN symbiotic bacteria were able to grow in the haemolymph of all the white grub species tested. The results indicate that the white grub species investigated tended to resist the initial penetration of most of the EPN studied, thus avoiding infection.The Tree Protection Cooperative Programme, TPCP, and the National Research Foundation of South Africa.https://brill.com/view/journals/nemy/nemy-overview.xmlhj2024BiochemistryForestry and Agricultural Biotechnology Institute (FABI)GeneticsMicrobiology and Plant PathologyZoology and EntomologyNon

Diversity and molecular barcoding of stink bugs (Hemiptera: Pentatomidae) associated with macadamia in South Africa

Stink bugs are major pests of macadamia in South Africa. Accurate identification and knowledge of species composition are important to inform management practices. The overall aims of this study were to identify stink bug species from macadamia orchards in South Africa using morphology, and to establish a DNA database based on the cytochrome c oxidase subunit 1 gene region. A total of 21 stink bug species were found in macadamia orchards in KwaZulu-Natal, Limpopo and Mpumalanga provinces. Bathycoelia distincta Distant, 1878, was the dominant species throughout all three growing regions. Two unidentified species of Boerias Kirkaldy, 1909, here designated as Boerias sp. 1 and Boerias sp. 2, were the second and third most abundant species found in KwaZulu-Natal. No species of Boerias has previously been reported in association with macadamia. Evidence of a cryptic third species of Boerias was also found. Species composition fluctuated over three growing seasons in Limpopo and differed between the three growing regions during the 2019–2020 season, highlighting the need for ongoing monitoring of these important pest species. The DNA barcode database developed in this study will be valuable for future monitoring and identifications, including cryptic or polymorphic stink bug species and different life stages.SUPPLEMENTARY MATERIALS : Table S1: Number of stink bug morphospecies found at each location across three seasons; Table S2: Seasonal presence of stink bug species per scout batch per region; Table S3: Collection details of specimens sequenced to determine species presence and composition of stink bugs in macadamia orchards in South Africa.DATA AVAILABILITY STATEMENT : Sequence data openly available in Genbank (www.ncbi.nlm.nih.gov) (accessed on 27 January 2022).The University of Pretoria, the Forestry and Agricultural Biotechnology Institute (FABI), the DSI-NRF Centre of Excellence in Plant Health Biotechnolog), Macadamias South Africa NPC (SAMAC) and NRF Thuthuka.https://www.mdpi.com/journal/insectsBiochemistryForestry and Agricultural Biotechnology Institute (FABI)GeneticsMicrobiology and Plant PathologyZoology and Entomolog

Leaf surface traits may influence host specificity in psyllids of Eucalyptus, Spondyliaspis cf. plicatuloides (Froggatt) and Glycaspis brimblecombei Moore (Hemiptera: Aphalaridae)

DATA AVAILABILITY : Data can be obtained from the corresponding author.Spondyliaspis cf. plicatuloides and Glycaspis brimblecombei (Hemiptera: Aphalaridae) are invasive insect pests of Eucalyptus, native to Australia. The insects feed on eucalypt sap, and both psyllid species exhibit clear preferences for different species and hybrids of Eucalyptus. The objective of this study was to identify the constitutive morphological and phytochemical characteristics underlying these host preferences. Four preferred and eight non-preferred eucalypt hosts were selected for evaluation. Thirteen leaf morphological features of the 12 eucalypts were analysed. The non-polar and polar metabolites in and on the surface of leaves of each eucalypt species were extracted, and their chemical composition was analysed using gas chromatography coupled with mass spectrometry. The leaf volatile profiles of hosts and non-hosts of S. cf. plicatuloides and G. brimblecombei did not differ sufficiently to explain the host choices of the two eucalypt psyllids. The leaf polar metabolite profiles of the susceptible hosts of the two psyllids differed significantly but did not explain the host preferences of the two psyllid species. However, preferred hosts of S. cf. plicatuloides and G. brimblecombei had some leaf morphological features and wax metabolites in common. Our results show that particular combinations of leaf morphological features and wax metabolites might influence the host choice of eucalypt-feeding lerp psyllids, but no traits explaining the differences in host-selection behaviour between S. cf. plicatuloides and G. brimblecombei were identified.Members of Tree Protection Cooperative Program (TPCP), DSI-NRF Centre of Excellence in Plant Health Biotechnology, University of Pretoria, South Africa. Open access funding provided by University of Pretoria.https://www.springer.com/journal/49am2024BiochemistryForestry and Agricultural Biotechnology Institute (FABI)GeneticsMicrobiology and Plant PathologyZoology and EntomologySDG-15:Life on lan

The balance of trade in alien species between South Africa and the rest of Africa

BACKGROUND : Alien organisms are not only introduced from one biogeographical region to another but also spread within regions. As South Africa shares land borders with six countries, multiple opportunities exist for the transfer of alien species between South Africa and other African countries; however, the direction and importance of intra-regional spread is unclear. OBJECTIVES : The aim of this study was to gain a greater understanding of the introduction of alien species into Africa and the spread of species between South Africa and other African countries. METHOD : We developed scenarios that describe the routes by which alien species are introduced to and spread within Africa and present case studies for each. Using data from literature sources and databases, the relative importance of each scenario for alien birds and insect pests of eucalypts was determined, and the direction and importance of intra-regional spread was assessed. RESULTS : Alien species from many taxonomic groups have, through various routes, been introduced to and spread within Africa. For birds and eucalypt insect pests, the number of species spreading in the region has recently increased, with South Africa being a major recipient of birds (14 species received and 5 donated) and a major donor of eucalypt insect pests (1 species received and 10 donated). For both groups, many introduced species have not yet spread in the region. CONCLUSION : The intra-regional spread of alien species in Africa represents an important and possibly increasing threat to biosecurity. To address this threat, we propose a framework that details how African countries could cooperate and develop a coordinated response to alien species introductions.This paper was initially delivered at the 43rd Annual Research Symposium on the Management of Biological Invasions in South Africa, Goudini Spa, Western Cape, South Africa on 18-20 May 2016.The South African National Department of Environment Affairs through its funding of the South African National Biodiversity Institute’s Invasive Species Programme, the DST-NRF Centre for Invasion Biology, the South African Research Chairs Initiative of the Department of Science and Technology and National Research Foundation of South Africa.http://abcjournal.org/index.php/ABCam2018Forestry and Agricultural Biotechnology Institute (FABI)Zoology and Entomolog

Steinernema fabii n. sp. (Rhabditida : Steinernematidae), a new entomopathogenic nematode from South Africa

A new species of entomopathogenic nematode, Steinernema fabii n. sp., was isolated by trapping with wax moth (Galleria mellonella) larvae from soil in an Acacia mearnsii plantation in the Mpumalanga province of South Africa. The new species is morphologically characterised by the length of the infective juvenile (IJ) of 641 (590-697) μm, by a tail length of 58 (52-64) μm, ratio a = 24 (21-41), H% = 53 (37-61) and E% = 93 (83-105). The pattern of the lateral field of the IJ of the new species is 2, 5, 2 ridges (3, 6, 3 incisures). The male of the first generation can be recognised by the long spicule of 90 (79-106) μm and gubernaculum of 66 (56-77) μm; D% = 64 (52-75) and GS% = 73 (63-86). The first generation female can be recognised by a protruding vulva, with a short double flapped epiptygmata and the lack of a postanal swelling, while the second generation differs with a post anal swelling and conical and sharply pointed tail. Analysis of DNA sequences for the ITS and D2D3 gene regions showed S. fabii n. sp. to differ from all other Steinernema species and to belong to a new monophyletic group, the ‘Cameroonian’ clade, consisting of S. cameroonense, S. nyetense, S. sacchari and S. fabii n. sp., all from the African continent. This group is closely related to species in the feltiaekraussei- oregonense Clade III.The Tree Protection Cooperative Programme (TPCP), the University of Pretoria and the National Research Foundation (NRF).http://booksandjournals.brillonline.com/content/journals/156854112018-02-28hb2016Forestry and Agricultural Biotechnology Institute (FABI)GeneticsZoology and Entomolog

The Sodium/Proton Exchanger NHE8 Regulates Late Endosomal Morphology and Function

The pH and lumenal environment of intracellular organelles is considered essential for protein sorting and trafficking through the cell. We provide the first evidence that a mammalian sodium (potassium)/proton exchanger, NHE8, plays a key role in the control of protein trafficking and endosome morphology

The ACTTION-APS-AAPM Pain Taxonomy (AAAPT) Multidimensional Approach to Classifying Acute Pain Conditions.

Objective: With the increasing societal awareness of the prevalence and impact of acute pain, there is a need to develop an acute pain classification system that both reflects contemporary mechanistic insights and helps guide future research and treatment. Existing classifications of acute pain conditions are limiting, with a predominant focus on the sensory experience (e.g., pain intensity) and pharmacologic consumption. Consequently, there is a need to more broadly characterize and classify the multidimensional experience of acute pain. Setting: Consensus report following expert panel involving the Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks (ACTTION), American Pain Society (APS), and American Academy of Pain Medicine (AAPM). Methods: As a complement to a taxonomy recently developed for chronic pain, the ACTTION public-private partnership with the US Food and Drug Administration, the APS, and the AAPM convened a consensus meeting of experts to develop an acute pain taxonomy using prevailing evidence. Key issues pertaining to the distinct nature of acute pain are presented followed by the agreed-upon taxonomy. The ACTTION-APS-AAPM Acute Pain Taxonomy will include the following dimensions: 1) core criteria, 2) common features, 3) modulating factors, 4) impact/functional consequences, and 5) putative pathophysiologic pain mechanisms. Future efforts will consist of working groups utilizing this taxonomy to develop diagnostic criteria for a comprehensive set of acute pain conditions. Perspective: The ACTTION-APS-AAPM Acute Pain Taxonomy (AAAPT) is a multidimensional acute pain classification system designed to classify acute pain along the following dimensions: 1) core criteria, 2) common features, 3) modulating factors, 4) impact/functional consequences, and 5) putative pathophysiologic pain mechanisms. Conclusions: Significant numbers of patients still suffer from significant acute pain, despite the advent of modern multimodal analgesic strategies. Mismanaged acute pain has a broad societal impact as significant numbers of patients may progress to suffer from chronic pain. An acute pain taxonomy provides a much-needed standardization of clinical diagnostic criteria, which benefits clinical care, research, education, and public policy. For the purposes of the present taxonomy, acute pain is considered to last up to seven days, with prolongation to 30 days being common. The current understanding of acute pain mechanisms poorly differentiates between acute and chronic pain and is often insufficient to distinguish among many types of acute pain conditions. Given the usefulness of the AAPT multidimensional framework, the AAAPT undertook a similar approach to organizing various acute pain conditions

Translocated LPS Might Cause Endotoxin Tolerance in Circulating Monocytes of Cystic Fibrosis Patients

Cystic Fibrosis (CF) is an inherited pleiotropic disease that results from abnormalities in the gene codes of a chloride channel. The lungs of CF patients are chronically infected by several pathogens but bacteraemia have rarely been reported in this pathology. Besides that, circulating monocytes in CF patients exhibit a patent Endotoxin Tolerance (ET) state since they show a significant reduction of the inflammatory response to bacterial stimulus. Despite a previous description of this phenomenon, the direct cause of ET in CF patients remains unknown. In this study we have researched the possible role of microbial/endotoxin translocation from a localized infection to the bloodstream as a potential cause of ET induction in CF patients. Plasma analysis of fourteen CF patients revealed high levels of LPS compared to healthy volunteers and patients who suffer from Chronic Obstructive Pulmonary Disease. Experiments in vitro showed that endotoxin concentrations found in plasma of CF patients were enough to induce an ET phenotype in monocytes from healthy controls. In agreement with clinical data, we failed to detect bacterial DNA in CF plasma. Our results suggest that soluble endotoxin present in bloodstream of CF patients causes endotoxin tolerance in their circulating monocytes