First report of the aphid parasitoid Aphidius ervi Haliday (Hymenoptera, Braconidae, Aphidiinae) from South Africa

In August 2010, Aphidius ervi Haliday (Hymenoptera, Braconidae, Aphidiinae) was reared from a sample of the potato aphid, Macrosiphum euphorbiae (Thomas), which was collected in the field on Malva parviflora L. (Malvaceae) at the Experimental Farmof the University of Pretoria, Pretoria, South Africa (25°45’03.6”S 28°15’28.9”E). This is the first record of this parasitoid from SouthAfrica.Voucher specimens are deposited in the South African National Collection of Insects, ARC-Plant Protection Research Institute,Pretoria (ARC-PPRI; accession numbers AcP 9504–AcP 9509).Aphidius ervi was identified by P. Star (Biology Centre, Institute of Entomology, Academy of Sciences of the Czech Republic). The identity of Macrosiphum euphorbiae was confirmed by I.M. Millar (Biosystematics Division, ARC-Plant Protection Research Institute, South Africa). M. Nel (Department of Plant Science, University of Pretoria) identified Malva parviflora.http://www.journals.co.za/ej/ejour_ento.htmlam201

Effect of SARS-CoV-2 proteins on vascular permeability.

Severe acute respiratory syndrome (SARS)-CoV-2 infection leads to severe disease associated with cytokine storm, vascular dysfunction, coagulation, and progressive lung damage. It affects several vital organs, seemingly through a pathological effect on endothelial cells. The SARS-CoV-2 genome encodes 29 proteins, whose contribution to the disease manifestations, and especially endothelial complications, is unknown. We cloned and expressed 26 of these proteins in human cells and characterized the endothelial response to overexpression of each, individually. Whereas most proteins induced significant changes in endothelial permeability, nsp2, nsp5_c145a (catalytic dead mutant of nsp5), and nsp7 also reduced CD31, and increased von Willebrand factor expression and IL-6, suggesting endothelial dysfunction. Using propagation-based analysis of a protein–protein interaction (PPI) network, we predicted the endothelial proteins affected by the viral proteins that potentially mediate these effects. We further applied our PPI model to identify the role of each SARS-CoV-2 protein in other tissues affected by coronavirus disease (COVID-19). While vali-dating the PPI network model, we found that the tight junction (TJ) proteins cadherin-5, ZO-1, and β-catenin are affected by nsp2, nsp5_c145a, and nsp7 consistent with the model prediction. Overall, this work identifies the SARS-CoV-2 proteins that might be most detrimental in terms of endothelial dysfunction, thereby shedding light on vascular aspects of COVID-1

Prospects for biological control of Chilo partellus in grain crops in South Africa

Chilo partellus (Swinhoe) was first recorded in South Africa in 1958 and became a major pest of maize and grain sorghum. It has invaded the main maize producing areas in the Highveld Region, gradually competitively displacing the indigenous Busseola fusca (Fuller). Between 1980 and 1993 two egg, seven larval and two pupal parasitoids were introduced for biological control of Ch. partellus. Cotesia flavipes Cameron (Braconidae), Paratheresia claripalpis van der Wulp (Tachinidae), Tetrastichus howardi (Olliff) (Eulophidae) and Xanthopimpla stemmator Thunberg (Ichneumonidae) were released and recovered from the field. Recoveries were made up to a few weeks after releases but parasitoids failed to survive the winter and establish. The harsh winter conditions in the release sites, the long larval diapause period of Ch. partellus, lack of synchronisation between the development of the parasitoids and that of their host larvae, and absence of alternative host plants were identified as the main obstacles for the parasitoids establishment. It is concluded that the prospects of achieving any degree of biological control of stemborers in the Highveld Region with parasitoids from the tropics are poor. A parasitoid from a temperate zone of the USA, Macrocentrus grandii Goidanich (Braconidae), was introduced recently into South Africa and is currently reared on Ch. partellus in quarantine. Macrocentrus grandii stays dormant in its diapausing host, Ostrinia nubilalis (Hubner), during winter to emerge in spring. Because of its ability to diapause in winter it is hoped that after releases, M. grandii will establish on Ch. partellus in the Highveld Region of South Africa. RÉSUMÉ Chilo partellus (Swinhoe) a été collecté pour la première fois en Afrique du Sud en 1958, depuis lors il est devenu le ravageur le plus important sur maïs et sorgho. Il a envahi la principale région productrice du maïs dans la région de haute altitude et graduellement a remplacé l'espèce locale Busseola fusca (Fuller). Entre 1980 and 1993 deux parasitoïdes des oeufs, sept larvaires et deux des pupes ont été introduits dans le cadre de la lutte biologique contre Ch. partellus. Cotesia flavipes Cameron (Braconidae), Paratheresia claripalpis van der Wulp (Tachinidae), Tetrastichus howardi (Olliff) (Eulophidae) et Xanthopimpla stemmator Thunberg (Ichneumonidae) ont été lâchées et re-collectés des champs. Les recollections ont duré quelques semaines après les lâchées, mais les parasitoïdes n'ont pas pu survivre l'hivers et s'acclimater. Les sévères conditions hivernales dans les sites où ont eu lieu les lâchées, la longue diapause de Ch. partellus, le manque de synchronie entre le dévéloppement des parasitoïdes et celui de la larve du ravageur et l'absence des plantes hôtes intermediaires sont cités comme les principaux obstacles à l'acclimatation des parasitoïdes. On en conclut que les possibilities de succes de la lutte biologique avec des parasitoïdes contre les foreurs dans la région de haute altitude sont très faibles. Un parasitoïde d'une zone tempérée aux USA, Macrocentrus grandii Goidanich (Braconidae), a été récemment introduit en Afrique du Sud et est élevé sur Ch. partellus en quarantaine. Pendant l'hivers, Macrocentrus grandii entre en dormance dans son hôte en diapause, Ostrinia nubilalis (Hubner), et émerge au printemps. A cause de cette capacité d'entree en diapause pendant l'hivers, on espère qu'après les lâchées M. grandii pourrait s'adapter et s'acclimater sur Ch. partellus dans la région de haute altitude de l'Afrique du Sud

Age-related reproductive biology of Trichogrammatoidea lutea on eggs of the African bollworm Helicoverpa armigera

Trichogrammatoidea lutea Girault (Hymenoptera Trichogrammatidae) is an egg parasitoid of the African bollworm Helicoverpa armigera (Hubner) (Lepidoptera Noctuidae) in southern Africa. To determine the potential of T. lutea as a biological control agent of H. armigera, longevity, daily parasitism, fecundity, number of progeny per egg and sex ratio with regard to maternal age were examined under laboratory. The maximum longevity of T. lutea male and female adults was 14 and 16 days, respectively. Reproduction by T. lutea commenced on the day of eclosion and lasted for 14 days. The mean realized fecundity of T. lutea was 52 offspring per female. Daily fecundity and sex allocation depended on maternal age. Daily percentage parasitism and fecundity were highest on the day of eclosion and decreased with female age until no egg was parasitized from day 15. The sex ratio was femalebiased during the first three days, and thereafter became male-biased from day 4 until day 14. The number of progeny per host egg was also highest at 2.2 on the day of eclosion, then decreased to 0.9 on day 8 and thereafter increased to 2.0 on day 13. The overall sex ratio of T. lutea was approximately 1:1. The net replacement rate (R0), mean generation time (T) and intrinsic rate of population increase (rm) of T. lutea were determined at 25.5, 9.8 and 0.3, respectively. Findings from this study show great potential of T. lutea as a biological control agent of H. armigera.African bollworm Helicoverpa armigeraProfessional Development Programme (PDP) of the ARC; ARC-PHP and Innovation Fund of the Department of Science and Technology (DST) administered by the National Research Foundation (NRF).http://www.bulletinofinsectology.orgpm2021Zoology and Entomolog