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Encephalartos eugene-maraisii is an endangered, endemic plant in the Waterberg Mountain range of South Africa. This is the first report of herbivory by Zerenopsis lepida (Lepidoptera: Geometridae) on natural populations of E. eugene-maraisii. The impact of herbivory by folivorous arthropods on this cycad species has not been studied before. This study aimed to determine the incidence and intensity of Z. lepida herbivory on E. eugene-maraisii under field conditions. Local plant dynamics were studied by recording the plant location, sex, size and phenological stage for each plant. Damage surveys were carried out over two consecutive seasons (2020–2021 and 2021–2022). Leaf damage was assessed on 227 plants comprising 692 stems. Approximately 40% of the stems had signs of leaf herbivory by Z. lepida and 10% of the total leaf area was removed by Z. lepida larvae. Less herbivory was recorded in areas where plants synchronously produced new leaf flushes compared to areas with asynchronous leaf flushes. Greater apparency of plants led to a greater incidence of herbivory and level of damage. Repeated damage to plants may delay future leaf and cone flushing events and contribute to the threat against this cycad species. [ABSTRACT FROM AUTHOR]

Busseola fusca and Fusarium verticillioides are considered the most important pest and pathogen, respectively, of maize in South Africa. Busseola fusca tunnels into stems and ears of maize plants, whereas F. verticillioides causes Fusarium ear rot and deposits fumonisins in maize kernels. Frass (excreta) deposited by B. fusca larvae in maize stems and ears during feeding could potentially be contaminated with pathogens such as F. verticillioides, thereby indirectly and passively contributing to plant diseases. The mycoflora present in frass of B. fusca larvae was thus investigated in this study, and the dissemination of fumonisin-producing Fusarium spp. by B. fusca larvae in maize stems determined. Busseola fusca frass was collected from plants with visible insect damage in three maize-growing districts in South Africa. The mycoflora in the frass was isolated and identified morphologically to genus level, followed by the sequencing of target genes for species identification. Species of Acremonium, Aspergillus, Fusarium, Mucor, Rhizopus and Talaromyces were associated with the B. fusca frass. The role of B. fusca larvae in disseminating fumonisin-producing Fusarium spp. was then determined in greenhouse and field trials. Maize whorls were inoculated withF. verticillioides MRC826 spores 4 weeks after plant emergence, and infested with B. fusca larvae 2 days later. The stems were split open after 3 weeks and frass collected from feeding channels, thereafter, target DNA of fumonisin-producing Fusarium spp. was quantified using real-time PCR. Target DNA of fumonisin-producing Fusarium spp. was significantly higher in frass collected from greenhouse plants inoculated with F. verticillioides than in frass collected from the uninoculated control, indicating that the inoculation was successful in the absence of soil-borne inoculum. Nevertheless, the field trial showed no significant differences in target DNA in frass from inoculated and non-inoculated plants. This is possibly due to natural F. verticillioidesinfection of maize plants in the field. This study further indicated that B. fusca frass also contained maize pathogens such asAspergillus spp. and Fusarium spp., which could cause ear rot diseases. The occurrence of Acremonium zeae in frass has potential implications for the biological control of F. verticillioides, as the fungus produces pyrrocidines A and B antibiotics which are known to be antagonistic to F. verticillioides. The occurrence of Aspergillus niger in frass requires further investigation in order to clarify its role in fumonisin contamination of maize in South Africa. [ABSTRACT FROM AUTHOR]

The article presents a study related to the susceptibility of Spodoptera littoralis (Boisduval) (Lepidoptera: Noctuidae) to Bt cotton, expressing Cry1Ac and Cry2Ab toxins, in South Africa. It mentions that spodoptera littoralis may cause considerable damage to cotton by feeding on the leaves, flower buds and occasionally, and also on bolls.

Various abiotic factors influence the biology and behaviour of arthropods, one of the most prominent abiotic factors is temperature. Thus, it is essential to know the optimal time of day during which sampling of target species should be done to allow for accurate arthropod biodiversity studies. This study considered species richness, abundance and diversity of predaceous arthropods of the Chrysopidae, Mantodea, Araneae and Coccinellidae throughout the day in and around maize fields in the extensively cultivated highveld grasslands of South Africa. Sweep net sampling was done at the following times: 07:00, 12:00, 15:00 and 17:00. Sampling was conducted at three different localities and repeated on three occasions over two growing seasons. At each locality there were three replicates in each of three zones in the agro-ecosystem, i.e. maize field, field margin and untransformed grassland. Shannon diversity index values did not differ significantly between the different sweep net sampling times. Predacious arthropods were, although not significantly so, more abundant within maize fields in the mornings (07:00) and in adjacent grasslands during late afternoon (15:00). This study indicated no particular time to be significantly better suited for sampling of the diversity of the four groups of predacious arthropods in maize agro-ecosystems. [ABSTRACT FROM AUTHOR]

Transgenic Bt maize expressing Cry insecticidal δ-endotoxins of Bacillus thuringiensis has been cultivated in South Africa for the control of Busseola fusca since 1998. Busseola fusca is resistant to Cry1Ab Bt maize at many localities throughout the maize production region. Pre-release evaluation (1994–1996) of the inherent susceptibility and post-release assessments (1998–2011) of resistance status of B. fusca focused on a limited number of pest populations. This study reports the current levels of susceptibility of 10 B. fusca populations evaluated between 2013 and 2017 and compared this data with previously reported data on the survival of this pest on Bt maize, including data of pre-release evaluations done during 1994 and 1995. Larval feeding bioassays in which plant tissue of maize events expressing either Cry1Ab or Cry1A.105+Cry2Ab2 (stacked event) proteins were conducted and survival and different life history parameters recorded. Results show a shift in levels of susceptibility of B. fusca to Bt maize. Pre-release evaluation of the single-gene event showed very low larval survival on Bt maize leaf tissue while studies 10 yr later and the current study reported survival of up to 40% and 100% on Cry1Ab maize, respectively. While no larvae completed their life cycle on the stacked event, higher LT50 values in this study indicate a shift in susceptibility of B. fusca to the stacked-gene event and highlight the importance of baseline information and monitoring of pest populations for their susceptibility to Bt maize. [ABSTRACT FROM AUTHOR]

Intensive, large-scale cultivation has led to a postulated decrease in biodiversity worldwide, which has been ascribed to fragmentation and degradation of natural habitat bordering crop fields. Maize is the most widely planted grain crop in Grassland and Savanna Biomes of South Africa, but the effect that crop production has on surrounding species diversity and composition is unknown. This study intends to address this knowledge gap by comparing diversity patterns and species assemblages between maize fields and margins of six localities in South Africa across two biomes for plants and associated arthropods. A total of 15,019 individuals and 824 native and exotic plant species were recorded and 39 497 individuals and 1 629 morpho-species for arthropods. Although biodiversity loss was apparent in maize fields, plant and arthropod diversity remained the same for rangeland at shorter (30-100 m) and longer (100-400 m) distances from maize fields, suggesting that distance from maize fields had no effect on biodiversity patterns beyond 30 m. Plant species assemblages were best correlated with agricultural disturbance while arthropod communities were mainly correlated with biome. Our results suggest that the crop field margins (30-100 m from field edge) were not species poor ecosystems, but were surprisingly rich in plant and arthropod diversity. Field margins may therefore be of conservation value in the agricultural landscape with a diversity of species supporting important ecosystem services. [ABSTRACT FROM AUTHOR]

Country-wide surveys of lepidopteran stem borers in wild host plants were undertaken between 2006 and 2009 in South Africa and 2005 and 2010 in Mozambique. A total of 4438 larvae were collected from 65 wild host plants in South Africa and 1920 larvae from 30 wild host plants in Mozambique. In South Africa and Mozambique, 50 and 39 stem borer species were recovered, respectively, with four new species and two new genera among noctuids. Less than 5% of the total number of species collected are considered to be economically important in Africa. These species were Busseola fusca ( Fuller) ( Noctuidae), Chilo partellus ( Swinhoe) ( Crambidae) and Sesamia calamistis Hampson ( Noctuidae). Data from this study and others in East Africa on the very low abundance of stem borers in wild host plants question the putative role of wild host plants as reservoir for stem borer pests. One new host plant family ( Prioniaceae), as well as 24 and 13 wild hosts from South Africa and Mozambique respectively, was added to the list of known hosts in Africa. [ABSTRACT FROM AUTHOR]

The biodiversity of an agroecosystem is not only important for its intrinsic value but also because it influences ecological functions that are vital for crop production in sustainable agricultural systems and the surrounding environment. A concern about genetically modified (GM) crops is the potential negative impact that such crops could have on diversity and abundance of nontarget organisms, and subsequently on ecosystem functions. Therefore, it is essential to assess the potential environmental risk of the release of a GM crop and to study its effect on species assemblages within that ecosystem. Assessment of the impact of Bt maize on the environment is hampered by the lack of basic checklists of species present in maize agroecosystems. The aims of the study were to compile a checklist of arthropods that occur on maize in South Africa and to compare the diversity and abundance of arthropods and functional groups on Bt maize and non-Bt maize. Collections of arthropods were carried out during two growing seasons on Bt maize and non-Bt maize plants at two localities. Three maize fields were sampled per locality during each season. Twenty plants, each of Bt maize and non-Bt maize, were randomly selected from the fields at each site. The arthropods collected during this study were classified to morphospecies level and grouped into the following functional groups: detritivores, herbivores, predators, and parasitoids. Based on feeding strategy, herbivores and predators were further divided into sucking herbivores or predators (piercing-sucking mouthparts) and chewing herbivores or predators (chewing mouthparts). A total of 8,771 arthropod individuals, comprising 288 morphospecies and presenting 20 orders, were collected. Results from this short-term study indicated that abundance and diversity of arthropods in maize and the different functional guilds were not significantly affected by Bt maize, either in terms of diversity or abundance. [ABSTRACT FROM AUTHOR]

The diversity of lepidopterous stem borers, their parasitoids and their associated wild host plants was studied in South Africa between 2006 and 2009 and in Mozambique between 2005 and 2010. In South Africa, 20 species of parasitoids were recovered from 17 stem borer species collected on 16 wild host plant species. From Mozambique, 14 parasitoid species were recorded from 16 stem borer species collected on 14 wild host plant species. The highest diversity of parasitoids was recorded on stem borers that attacked the host plants Phragmites australis (7 spp.) and Panicum maximum (6 spp.), in South Africa and Mozambique, respectively. Bracon sp. (Hymenoptera: Braconidae) and Procerochasmias nigromaculatus (Hymenoptera: Ichneumonidae) were the most recorded parasitoid species in South Africa while Cotesia sesamiae (Hymenoptera: Braconidae) parasitized most stem borer species in Mozambique. The most common tachinid parasitoid recorded in this study was Sturmiopsis parasitica (Diptera: Tachinidae). Parasitism of stem borers during the off season was previously thought to occur mainly in natural habitats but this study shows that although natural habitats provided refuges for some parasitoid species, stem borer parasitism was generally low in wild host plants, irrespective of whether collections were done during the cropping or off-season. Parasitoid beta diversity did not depend on habitat or host plant species, but was determined by stem borer diversity. [ABSTRACT FROM AUTHOR]

Based on surface area, South Africa is currently ranked the eighth in planting genetically modified (GM) crops in the world. Bt maize (MON810) has been grown to control lepidopterous stem borers in South Africa since its first release during 1998. The first report of resistance of the African maize stem borer, Busseola fusca (Lepidoptera: Noctuidae) and poor compliance to refuge requirements that could have contributed to resistance development prompted this study which was done in the main maize production area of South Africa. Objectives were to evaluate farmer's perceptions of the regulatory aspects guiding the planting of Bt maize and refugia and how it was applied between 1998 and 2010. This study involved 105 commercial farmers covering 87 778 ha of maize throughout the main maize production region on the Highveld of South Africa. A questionnaire survey was conducted and addressed signing of technical agreements upon purchasing GM seed, refuge compliance, pest management practices, perceived benefits and risks relating to Bt maize. Compliance with refugia requirements was low especially during the initial 5-7 years after release. An alarmingly high number of farmers applied insecticides as preventative sprays on Bt maize and refugia irrespective of stem borer infestation levels. A large proportion of farmers reported significant borer infestation levels on Bt maize and between 5% and 93% farmers in all districts applied insecticides to Bt maize to limit borer damage, indicating that the occurrence of resistance is more wide-spread in the country than previously thought. This study shows irresponsible management of GM crop technology by farmers, chemical and seed companies. Concerns and perceptions of farmers in South Africa seem to differ from those in Europe. South African farmers perceived little, if any, negative impact on non-target organisms and remain positive about the technology in spite of resistance development. Other studies indicated that European farmers were concerned about these aspects. A shared concern, however, was consumer acceptance of GM maize and marketability on the export market. [ABSTRACT FROM AUTHOR]

The first report of resistance of the maize stem borer [Busseola fusca (Fuller)] to Bt maize (MON810) was made in the Christiana area of South Africa during 2007. The objective of this study was to evaluate the status of resistance of other populations of B. fusca to Bt maize. One greenhouse and two laboratory studies were conducted. B. fusca populations were collected on Bt maize as well as the adjacent refugia (conventional maize and non-Bt maize) in the Vaalharts area, 50 km from the Christiana site. Control populations were collected from sites where Bt maize was not planted. In the greenhouse study 720 potted plants were each artificially infested with 10 neonate larvae of the F1-generation after the field collected populations were reared through to adults. Numbers of live larvae and larval mass per plant were determined at regular intervals over a 35-d period. Larvae of the Christiana conventional population (Bt-susceptible) on Bt maize (CHR08Con-Bt) and Bethal conventional population (Bt-susceptible) on Bt maize (BET08Con-Bt) did not survive on Bt maize for longer than 12 d. The populations collected from both Bt (VAA08Bt-Bt) maize and refuges (VAA08Ref-Bt) at Vaalharts were resistant and the subsequent generation of larvae completed their life cycle on Bt maize. Similar results were observed in the laboratory experiments. This study confirmed resistance of B. fusca to the Cry1Ab toxin (MON810). The geographical distribution of resistance was shown to include at least the Vaalharts area, in addition to the original report for the Christiana area. These observations that larvae collected from refugia at Vaalharts was resistant, show that the efficacy of the refuge strategy is compromised in this area because the contribution of refugia did not produce large enough numbers of susceptible individuals to mate with moths of which larvae survived inside Bt maize fields. [ABSTRACT FROM AUTHOR]

Abstract: Bt maize has been grown at the Vaalharts irrigation scheme in South Africa since its first release during 1998. Interest in Bt maize refuge compliance, pest incidence and production practices at Vaalharts were recently stimulated by the first report of field resistance of Busseola fusca (Lepidoptera: Noctuidae) to Bt maize. Objectives of this study were to evaluate farmer''s perceptions of the regulatory aspects guiding the planting of Bt maize and refugia and how the field situation developed between 1998 and 2008. A survey, using a self-administered questionnaire, was conducted amongst 80 farmers at the irrigation scheme. The questionnaire addressed signing of contracts upon purchasing genetically modified (GM) seed, refuge compliance, refuge design and general farming practices. Farmers were also questioned on the perceived benefits and disadvantages of Bt maize and their perceptions of the pest status of B. fusca. The two greatest advantages associated with Bt maize were indicated to be convenient management (88%) and increased productivity (61.3%) while 42.5% indicated that they perceived Bt-technology to be environmental friendly. Initial levels of refuge compliance were low, and even though farmers were obligated to plant a refuge area for each Bt maize field, only 7.7% of farmers planted refuges during 1998. This number increased to 100% during 2008. Eight percent of farmers, however, indicated that they did not plant a refuge field for each Bt maize field, which was justified on the basis of small farm sizes (25ha). Nearly all farmers (99.8%) allow no spatial separation between the Bt maize field and adjacent refuge area. Farmers preferred to plant the refuge option where 5% of the field area is planted to conventional maize, which is not sprayed with insecticide instead of the 20% refuge area on which insecticide application against the target pest is allowed. In South Africa stewardship programs instituted during the 2008/2009 growing season, involve grower education programs as well as the compulsory signing of contracts between companies and farmers that contractually bind them to comply with refuge requirements accompanied by on-farm inspections. It appears that stem borer resistance to Bt maize in the Vaalharts area resulted from a combination of a late general planting date with consequent increased levels of infestation and variance in time of planting providing a continuous supply of moths. [Copyright &y& Elsevier]

Surveys to investigate the distribution and abundance of stem borers in natural habitats were conducted in February 2006 and January–February 2007. The surveys included eastern, northern and central parts of South Africa as well as three localities in Lesotho. During the surveys, Eldana saccharina Walker was recovered from three new localities in inland South Africa and two new indigenous hosts, Phragmites australis Cav. and Panicum maximum Jacq. from Boskop in the North-West Province and Oribi Gorge in KwaZulu-Natal respectively. Populations of E. saccharina in different parts of Africa are known for their differences in larval feeding behaviours, host plant choice and natural enemies. It is important to understand the origin of the newly recovered population for prevention of incursion and efficient management in case it invades crops. Molecular analysis indicated that the populations recovered in these new locations and from the new host plants are part of the southern African population of E. saccharina. With change in climate, and disturbance in wetlands the insect is expected in the future to be more abundant and problematic in inland areas of southern Africa. [ABSTRACT FROM AUTHOR]

Abstract: Maize, expressing Cry1Ab insecticidal proteins produced by the bacterium Bacillus thuringiensis (Bt), was introduced for control of Busseola fusca (Fuller) (Lepidoptera: Noctuidae) and Chilo partellus (Swinhoe) (Lepidoptera: Crambidae) in South Africa in 1998. In the light of the reportedly lower toxicity of Bt maize to certain noctuid borers, the effect of Bt maize was evaluated on Sesamia calamistis (Hampson) (Lepidoptera: Noctuidae) in South Africa. The characteristic larval behaviour of S. calamistis may result in reduced exposure to Bt toxin and subsequent high levels of survival since larvae do not feed on plant whorls like other borer species, but penetrate stems directly from behind leaf sheaths. Growth and survival of larvae were determined in a greenhouse bioassay with two Bt maize hybrids (Monsanto event MON810 and Syngenta event Bt11) and their non-Bt, isoline hybrids. Potted plants were artificially infested with 1st instar larvae. Percentage larval survival and mean larval mass were recorded over time. Bt maize of both events was shown to be highly toxic to S. calamistis. No larvae survived longer than 9 days on plants of either of the Bt events. S. calamistis is stenophagous and occurs in mixed populations with other borer species, with which it shares several parasitoid species in Africa. The ecological impact of local extinction of S. calamistis caused by this highly effective transgenic event is therefore not expected to be great. [Copyright &y& Elsevier]

Studies were conducted to assess the numerical response of ground-dwelling arthropods to a habitat management system (‘push–pull’) developed to control maize stemborers using spiders (Araneae) as an indicator group. In this cropping system, maize is intercropped with a stemborer moth-repellent (push) plant while an attractant trap crop (pull) is planted around this intercrop. Two study sites in western Kenya and one site at the Grain Crops Institute of the Agricultural Research Council in Potchefstroom, South Africa, were sampled. Treatments comprised a maize monocrop and an intercrop of maize and desmodium, Desmodium uncinatum Jacq., with Napier grass, Pennisetum purpureum (Schumach), as a trap crop around the field (‘push–pull’) in each site. Experiments were laid out in a completely randomized design with four replications at each site. Ground-dwelling spiders were sampled using a combination of pitfall traps and soil samples. A total of 2175 spiders, 78 species in 18 families, were recovered in Kenya and 284 spiders, 34 species in nine families, were recovered in South Africa. Lycosidae was the most abundant family, accounting for >50% of all individual spiders and 27.6% by species richness. Spiders were significantly more abundant at the Kenyan sites than in South Africa while species diversity was significantly higher in South Africa than at the Kenyan sites. At all sites, spider abundance was significantly higher in the ‘push–pull’ than in the maize monocrop plots. However, the overall spider diversity was only significantly higher in the ‘push–pull’ than in the maize monocrop plots in South Africa. Moreover, species dominance did not differ between the two cropping systems at all sites. The results showed that the ‘push–pull’ system evidently enhances overall abundance of spiders, illustrating its potential in further pest control in the maize agroecosystems where spiders may often be one of the most important predatory groups. [ABSTRACT FROM AUTHOR]

Abstract: During the past two decades, panicle-feeding Hemiptera (head bugs) became serious pests of sorghum in West and Central Africa. Of the more than 100 sorghum insect pests reported in Africa, 42 species are reported to be panicle-feeding pests. Prior to this study, no research had been done on the panicle-feeding Hemiptera in South Africa. The objectives of the study were to determine the abundance and diversity of panicle-feeding Hemiptera on sorghum. Surveys were conducted between November 2004 and June 2006 at 26 sites in four provinces of South Africa. Collection was done using a plastic bag method and a D-Vac. A checklist was compiled and the temporal distribution of different Hemiptera species determined during panicle development. The total number of adults and nymphs collected during this study was 23,798. Thirty-nine herbivorous Hemiptera species were collected. The most abundant family was the Miridae followed by the Lygaeidae, which made up 41% and 17%, respectively, of the total number of individuals. Eurystylus bellevoyi, Campylomma sp., Creontiades pallidus, Nysius natalensis, Nezara viridula and Sthenaridea suturalis were the most abundant species and also occurred widely in the sorghum production area. Infestation levels of these species were generally low compared with those in other parts of Africa, but comparatively high infestation levels were observed at some sites. There was no clear distinction between the different panicle development stages during which panicles were infested by different species. The general tendency was that nearly all species were present from the flowering stage onwards and that numbers declined when grain hardened. [Copyright &y& Elsevier]

Bt maize, Zea mays L. (Poaceae) expressing Cry 1Ab insecticidal proteins was introduced for control of Busseola fusca (Fuller) (Lepidoptera: Noctuidae) and Chilo partellus (Swinhoe) (Lepidoptera: Crambidae) in South Africa after its development for control of crambid borers in North America. In the light of the reportedly lower toxicity of Bt maize to certain Noctuidae borers, the effect of Bt maize was evaluated on Sesamia calamistis (Hampson) (Lepidoptera: Noctuidae). The characteristic larval behaviour of S. calamistis may result in reduced exposure to Bt toxin and subsequent high levels of survival. Larvae do not feed on plant whorls like other borer species but penetrate stems directly from behind leaf sheaths where eggs are laid. Greenhouse and laboratory bioassays were done with three Bt maize hybrids and their iso-hybrids. ‘Whole plant methods’ were used and potted plants artificially infested with eggs or larvae and survival recorded over time. Larval survival was also determined on different plant parts (whorls, stems, tillers, and ears) over time. Bt maize was shown to be highly toxic to S. calamistis. No larvae survived longer than 12–18 days on Bt maize plants in any of the experiments. Adults did not differentiate between Bt and non-Bt plants in oviposition choice experiments. Sesamia calamistis is polyphagous and occurs in mixed populations with other borer species with which it shares many parasitoid species in Africa. The ecological impact of local extinction of S. calamistis caused by this highly effective transgenic event is therefore not expected to be great. [ABSTRACT FROM AUTHOR]

Intensive, large-scale cultivation of food crops has led to major biodiversity loss worldwide due to fragmentation and degradation of remnant semi-natural habitat within agro-ecosystems. The response of vegetation to these disturbances is often measured in terms of taxonomic diversity loss. However, some plant groups may have more pronounced negative reactions to agricultural disturbance than others, which may not necessarily be expressed in the overall species diversity of the community. It is now widely accepted that the responses of plant taxa to environmental disturbances may be more directly linked to characteristics or traits that enable or hinder their persistence in disturbed environments. This highlights the need to assess the impacts of agricultural disturbance on the abundance patterns and diversity of specific plant traits and functional types. Maize agriculture is a common land-use feature in the grassy biomes of South Africa, but the effect that crop production has on surrounding semi-natural vegetation is still relatively unknown. In this study, we describe the specific functional trait patterns of plant communities associated with maize agro-ecosystems in six localities situated within the Grassland and Savanna biomes of South Africa. Although functional diversity was severely decreased in maize fields, marginal vegetation (30–100 m from crop field edges) displayed no indication of functional diversity loss or major changes in trait composition. Chamaephytic and hemicryptophytic (perennial) life forms, nitrogen-fixing ability and spinescence were trait attributes that were most frequently found in semi-natural vegetation but were lost in the crop field environment. Inside the maize fields, these trait attributes were replaced by annual, low-growing individuals with clonal parts and long-range dispersal mechanisms that can establish in the ephemeral crop field environment. Observed patterns were different for grassland and savanna maize fields, indicating that maize fields situated in the Grassland and Savanna biomes favoured different plant trait assemblages. [ABSTRACT FROM AUTHOR]

The groundnut leaf miner is a new pest in South Africa which arrived in 2001 from east Africa. Farmers are familiar with the damage symptoms caused by this pest but not of the causing factor which are the larvae that spin leaves together. Except for chemical control, no other control measures are available. [ABSTRACT FROM AUTHOR]

Callioratis millari Hampson (Lepidoptera: Geometridae) is a Critically Endangered moth endemic to South Africa. Despite extensive searches, it was previously known only from the Entumeni Nature Reserve in KwaZulu-Natal, where its larvae exclusively feed on the cycad Stangeria eriopus (Kunze) Baill (Cycadales: Stangeriaceae). In July 2022, a new population of C. millari was discovered in the Kabouga section of Addo Elephant National Park in the Eastern Cape. Larvae of C. millari were feeding on the cycad Encephalartos caffer (Thunb.) Lehm (Cycadales: Zamiaceae), which also constitutes a new host record. In June 2023, we determined larval incidence and herbivory at this new locality, offering insights into the ecological requirements of C. millari. Known C. millari localities, although ecologically different, share low altitudes (700-950 m a.s.l.), moderate to high rainfall, and grassy habitats with sparse woody cover. A total of 59 larvae were counted in Kabouga, mostly in the fifth and sixth (final) instars. Herbivory incidence was lower on smaller plants and those covered by other vegetation. The flight period of adult C. millari likely occurs between mid-March and April in Kabouga, but further investigation is needed to clarify this. The peak period of larval occurrence in Kabouga occurs during the driest and coldest months of the year (May-July). Considering limited habitat availability, host plant poaching, and the risk of untimely fires, the species should be considered highly threatened. This study adds to our understanding of the biology of C. millari and provides information on its ecological requirements and may contribute to making informed management decisions., (© The Author(s) 2024. Published by Oxford University Press on behalf of Entomological Society of America.)

The recent invasion of Africa by fall armyworm, Spodoptera frugiperda, a lepidopteran pest of maize and other crops, has heightened concerns about food security for millions of smallholder farmers. Maize genetically engineered to produce insecticidal proteins from the bacterium Bacillus thuringiensis (Bt) is a potentially useful tool for controlling fall armyworm and other lepidopteran pests of maize in Africa. In the Americas, however, fall armyworm rapidly evolved practical resistance to maize producing one Bt toxin (Cry1Ab or Cry1Fa). Also, aside from South Africa, Bt maize has not been approved for cultivation in Africa, where stakeholders in each nation will make decisions about its deployment. In the context of Africa, we address maize production and use; fall armyworm distribution, host range, and impact; fall armyworm control tactics other than Bt maize; and strategies to make Bt maize more sustainable and accessible to smallholders. We recommend mandated refuges of non-Bt maize or other non-Bt host plants of at least 50% of total maize hectares for single-toxin Bt maize and 20% for Bt maize producing two or more distinct toxins that are each highly effective against fall armyworm. The smallholder practices of planting more than one maize cultivar and intercropping maize with other fall armyworm host plants could facilitate compliance. We also propose creating and providing smallholder farmers access to Bt maize that produces four distinct Bt toxins encoded by linked genes in a single transgene cassette. Using this novel Bt maize as one component of integrated pest management could sustainably improve control of lepidopteran pests including fall armyworm., (© The Author(s) 2021. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: There is a void in research that focuses on how OT programs facilitate self-esteem in forensic mental healthcare users' return-to-work in the open labor market, particularly in South Africa., Objective: To explore the experiences and perceptions of forensic mental healthcare users, transitioning from an OT program to the open labor market., Methods: Five individuals, diagnosed with Schizophrenia, and two key informants participated in this study that was positioned in a qualitative paradigm, with an exploratory and descriptive design. Semi-structured interviews were used to collect data., Results: Theme one reflects on the challenges experienced by forensic mental healthcare users, when returning to work. Theme two describes various OT programs, as well as how they facilitate the reintegration of forensic mental healthcare users into the worker role. Theme three describes the positive support for forensic mental healthcare users, in the mental healthcare setting, workplace, and the greater community. Theme four describes how participation in occupation installs hope in forensic mental healthcare users, reinforcing the value of work, while positively influencing their work identity., Conclusion: The results revealed that stigma, residual symptoms, relapse due to substance abuse/mental health, and the lack of family support, were not be conducive to work skills development. However, the support of family and friends, workplace occupational therapy support, assembly line work, and therapeutic groups in an OT program, ensured positive workplace reintegration.

Spodoptera frugiperda (J.E. Smith) is an invasive pest species that threatens maize production by small holder farmers in Africa. Bt maize that express Cry proteins have been used effectively for control of this pest in the United States, Canada, and several countries in South America. Spodoptera frugiperda has evolved resistance to Cry1F Bt maize in Puerto Rico, Brazil and United States, and Cry1Ab Bt maize in Brazil. This study provides the first data on the efficacy of Bt maize for the control of S. frugiperda in Africa. Susceptibility levels of nine S. frugiperda populations were evaluated between January 2018 and May 2018, including a laboratory reared reference population. Larval feeding bioassays were conducted in which plant tissue of maize expressing Cry1Ab (single-toxin event - designated Bt1) or Cry1A.105 + Cry2Ab2 (pyramid-toxin event - designated Bt2), were fed to larvae. Survival and different life history parameters were recorded. Results indicate moderate survival on Bt1 maize, which supports field observations of commercial level control provided by this event. Very high levels of S. frugiperda larval mortality occurred on Bt2 maize (<1% survival). The moderate susceptibility of S. frugiperda to Cry1Ab could be ascribed to the latter being a low-dose event for this pest, as well as the fact that the individuals which initially arrived on the continent may have carried alleles with resistance to this protein. Moderate overall survivorship (4-35%) of S. frugiperda on Cry1Ab maize in South Africa reflects the possible presence of alleles resistant to this toxin, indicating the importance of future resistance monitoring., (© The Author(s) 2019. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: Products of plant biotechnology, for example genetically modified Bt maize, provide useful tools for pest management. The benefits provided by insect-resistant plants are, however, threatened by the evolution of resistance by target pest species. The high-dose/refuge insect resistance management strategy (IRM) as well as seed mixtures are globally used as IRM strategies. Busseola fusca (Lepidoptera: Noctuidae), the target stem borer of Bt maize in Africa, evolved resistance to Bt maize expressing Cry1Ab protein in South Africa. Owing to high larval mobility and subsequent sublethal exposure of larvae moving between non-Bt and Bt plants, more rapid resistance evolution has been proposed as a possibility with deployment of seed mixture strategies., Results: Laboratory and field studies were conducted to study B. fusca larval mobility. In the laboratory, different scenarios of B. fusca larval movement between single-gene (Cry1Ab) and stacked-trait (Cry1A.105 and Cry2Ab2) Bt maize were studied. Data on larval survival and mass over time indicated that Cry proteins do not kill larvae above certain developmental stages. A 2 year field study with the single gene and the stacked event was conducted using seed mixtures containing 5, 10, 15 and 20% non-Bt seed as well as a control treatment (non-Bt seed only)., Conclusion: Larval movement continued for 5 weeks and resulted in a significant incidence of Bt and non-Bt damaged plants, indicating that the movement behaviour of B. fusca is of such a nature that seed mixtures as an IRM strategy may not be effective to delay resistance evolution. © 2016 Society of Chemical Industry., (© 2016 Society of Chemical Industry.)

The host plant range of pests can have important consequences for its evolution, and plays a critical role in the emergence and spread of a new pest outbreak. This study addresses the ecological genetics of the indigenous African maize stem borer, Busseola fusca (Fuller) (Lepidoptera: Noctuidae), in an attempt to investigate the evolutionary forces that may be involved in the recent host range expansion and establishment of this species in Ethiopian and southern African sugarcane. We used populations from Ethiopia, Zimbabwe, and South Africa to examine whether the host range expansion patterns shared by the Ethiopian and the southern African populations of B. fusca have evolved independently. Base-pair differences in the cytochrome oxidase I (COI) gene were used to characterize haplotype diversity and phylogenetic relationships. There were seven haplotypes among the 30 sequenced individuals collected on four host plant species from 17 localities in the four countries. Of the seven COI haplotypes identified, the two major ones occurred in both sugarcane and maize. Genetic analyses revealed no detectable genetic differentiation between southern African B. fusca populations from maize and sugarcane (FST = 0.019; P = 0.24). However, there was strong evidence of variation in genetic composition between populations of the pest from different geographic regions (FST = 0.948; P < 0.001). The main implication of these findings is that the B. fusca populations in maize in southern Africa are more likely to shift to sugarcane, suggesting that ecological opportunity is an important factor in host plant range expansion by a pest., (© The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Nysius natalensis Evans (Hemiptera: Orsillidae) is a pest of sunflower in South Africa. Adults invade sunflower fields from their weedy hosts. The host plant suitability for development and survival and the effect of between-generation host switching were studied on different wild host plants and sunflower. Parameters used to assess host plant suitability were nymphal development, head widths, mean mass, and survival. Nymphs and adults were provided with crushed seed of five host plants, as well as a combination of seeds of the five species. Duration of the nymphal stage, development and mortality, and mean development time to adult were recorded. Between-generation host switching was studied by providing first-instar nymphs (F2) with seed of either the same plant species or transferred to different ones. Mean mass and mean head widths of adults (F2) were determined. The food source during the first and second generation, as well as the interaction thereof, has a significant effect on head widths of resultant males and females, as well as on female mass, but first-generation food did not have a significant effect on male mass. Feeding the F2 on sunflower proved to be beneficial to the false chinch bug, as it provided the heaviest males and females as well as females with the biggest head widths. Lack of constant availability of moisture had a detrimental effect on longevity. Host plant switching to sunflower likely happens as a result of senescence of wild host plants prior to winter., (© The Author 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Violence is a serious problem in South Africa with many effects on health services; it presents complex research problems and requires interdisciplinary collaboration. Two key meta-questions emerge: (i) violence must be understood better to develop effective interventions; and (ii) intervention research (evaluating interventions, assessing efficacy and effectiveness, how best to scale up interventions in resource-poor settings) is necessary. A research agenda to address violence is proposed.

The objective of this study was to determine the safety and efficacy of atovaquone and proguanil hydrochloride combination therapy for the prophylaxis of Plasmodium falciparum malaria in at-risk nonimmune subjects in South Africa. This open-label trial was conducted at research sites in South Africa during the main malaria transmission season, February through July. The study volunteers were temporarily living in, or traveling to, a malaria-endemic area. They received I tablet of 250 mg atovaquone and 100 mg proguanil hydrochloride once daily for up to 10 weeks. Subjects were monitored using sequential clinical and laboratory assessments. Thick blood smears were stained and evaluated by a central laboratory. An immunochromatographic test for P. falciparum was also used for on-site patient management. Prophylactic success was summarized using a 95% confidence interval for the proportion of subjects who did not develop parasitemia or who withdrew due to a treatment-related adverse event. A total of 175 subjects (15% women) were enrolled in the trial. The mean duration of drug exposure was 8.9 weeks. The combination of atovaquone and proguanil hydrochloride was well tolerated. The most frequently reported adverse events considered possibly related to study treatment were headache (7%), abdominal pain (2%), increased cough (2%), and skin disorder (2%). No serious adverse events were reported, and no treatment-emergent effects were noted for any laboratory variables. One subject who was noncompliant with therapy developed parasitemia, and 3 subjects withdrew due to a treatment-related adverse event (2 subjects with headache and 1 with nausea and dizziness). The prophylaxis success rate was 97%. In this study, atovaquone and proguanil hydrochloride combination therapy had an excellent safety and efficacy profile for prophylaxis of P. falciparum malaria in nonimmune subjects.