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Murray-Darling Freshwater Research CentreMDFRC item.The Kalahari Gemsbok National Park in the Northern Cape Province, South Africa, is bounded by two dry river beds in which 39 artificial water sources have been provided for the use of the wild animals. The water in these sources varies from fresh to highly saline and an opportunity is thus provided to determine, not only which rotifer species are able to colonise such sources, but what their salinity tolerances are. The rotifer fauna, studied in summer and winter, is dominated by mixed populations of Brachionus calyciflorus, B. plicatilis and Hexarthra jenkinae, with only a few other monogononts and bdelloids. The most striking feature of the rotifer fauna in these troughs is the very low species diversity encountered.

In August 2019, economist Johan Fourie of Stellenbosch University invited Historia to publish a "reflection piece" he had written and presented in March that year at the University of the Free State. In it, he puts forward his views of what History does, what it ought to do, and how it can perhaps be done better here in (South) Africa. His central concern is with big data and digitising records. He issues a number of seemingly bold challenges and provocations to historians. A slightly edited version of that piece is reproduced below. Rather than publish it as a stand-alone piece, however, and in the spirit of respectful exchange, we are publishing four substantial engagements with several of the arguments made by Fourie. These responses are by Faeeza Ballim, Gerald Groenewald, Jennifer Upton and Tinashe Nyamunda, all of whom are experts in their respective fields and experienced in their craft. Each takes the substantive points made by Fourie seriously, and responds to them in different ways. Best read as perspectives on a complex and enduring debate amongst people who are mindful of the politics of the past as well as being critically engaged with what historians "do" in the present, they recognise the technological and methodological promises of digital histories and big data, but eloquently remind us too of their limitations and indeed their potential pitfalls. There is much more to discuss, not the least of which is the responsibility for the ownership of and access to such records in a democratic and socially just world. The authors' information is included at the close, after a brief "Response" by Fourie.

Objectives Globally, tuberculosis (TB) incidence and mortality are declining; however, low detection of drug-resistant disease threatens to reverse current progress toward global TB control. Multiple, rapid molecular diagnostic tests have recently been developed to detect genetic mutations in Mycobacterium tuberculosis (Mtb) known to confer anti-TB drug resistance. Their utility, though, depends on the frequency and distribution of the resistance-associated mutations in the pathogen population. Therefore, this review aimed to assess the prevalence of the gene mutations associated with rifampicin (RIF) and isoniazid (INH) resistant Mtb in Ethiopia. Methods Using PRISMA guidelines, we searched the literature on PubMed/MEDLINE, Web of Science, Scopus, and Cochrane library databases. Data analysis was conducted in STATA 11. Results In total, 909 (95.8%) of 949 INH resistant Mtb isolates had detectable gene mutations: 95.8% in katG315 and 5.9% in the inhA-promoter region. The meta-analysis resulting an estimated prevalence of katGMUT1(S315T1) was 89.2% (95%CI:81.94-96.43%), while a pooled prevalence of inhAMUT1 (C15T) was 77.5% (95%CI:57.84-97.13%). Besides, 769 (90.8%) of 847 RIF resistant strains had detectable rpoB gene mutations, and the meta-analysis resulting in a pooled prevalence of rpoBMUT3 (S531L) was 74.2% (95%CI: 66.39-82.00%). Conclusions RIF-resistant Mtb isolates were spread widely, particularly those harboring S531L mutations. Similarly, INH-resistant Mtb strains with S315T1 and C15T mutations were common. Tracking S531L, S315T1, and C15T mutations among RIF and INH resistant isolates, respectively, would be diagnostically and epidemiologically valuable. Rapid diagnosis of RIF and INH-resistant Mtb in TB patients would expedite alteration of treatment regimens, and proper timely infection control interventions could reduce the risk of progression and transmission of multidrug-resistant TB (MDR-TB).

Information about the non-target effects of glyphosate, a broad-spectrum systemic herbicide on soil-borne nematodes is scarce and not well documented for South African agricultural fields. In the present study, the abundance and identity of plant-parasitic nematodes in roots and rhizosphere soil of commercial glyphosate- tolerant (genetically modified; GM) and conventional (non-glyphosate-tolerant) soybean cultivars from cultivated fields were obtained for two consecutive growing seasons. Grass and soil from adjacent natural vegetation were sampled, representing the reference system. Thirty plant-parasitic nematode species, belonging to 13 genera were identified in the roots and rhizosphere soil of soybean cultivars and natural vegetation. In rhizosphere soil, Meloidogyne (for glyphosate-tolerant and conventional soybean), followed by Helicotylenchus (for glyphosate-tolerant soybean) and Scutellonema (for conventional soybean), were the predominant genera. Seven species, namely Pratylenchus flakkensis, Pratylenchus scribneri, Pratylenchus vulnus, Rotylenchus brevicaudatus, Telotylenchus avaricus, Tylenchorhynchus brevicaudatus and Quinisulcius capitatus are first reports for soybean in South Africa. Although it was not possible to define the impact of each ecosystem on the plant-parasitic nematode assemblages, this study suggested that glyphosate had no deleterious effects on plant-parasitic nematodes

The introduction of genetically modified glyphosate-resistant (GR) crops led to increased use of glyphosate, with potential long-term effects on biological soil communities. Abundance and diversity of plant-parasitic and non-parasitic nematodes, as well as microbial community structure in the rhizosphere of GR and conventional soybean (CS) plants as well as native plants (mainly grasses) that grew in natural veld (NV), were investigated during one growing season. No significant differences (p ≥ 0.05) existed between the non-parasitic nematode trophic groups (dominated by bacterivores) and different plant-parasitic nematodes (dominated by the family Hoplolaimidae) that were present in all soils where GR and CS crops were grown or in NV areas. Faunal analysis of non-parasitic nematodes indicated that 83% of the sites contained enriched, but unstructured soil food-webs while 17% were identified as enriched and structured. No significant differences (p ≥ 0.05) existed for microbial community structures among the GR, CS and NV ecosystems with soils from all three primarily dominated by bacteria. Positive relationships were found between nematode trophic groups and their corresponding microbial prey. This emphasises the value of these organisms as indicators of soil quality and also the impact that agricultural practices can have on soil food webs

Dogs are reservoir hosts for Leishmania infantum, a protozoan parasite transmitted by phlebotomine sand flies. The anti-feeding and fast-killing efficacy of Scalibor® deltamethrin collars against experimental Phlebotomus perniciosus challenges on dogs was determined over 1 year. Two groups of 8 dogs each were fitted with placebo (control) or deltamethrin collars (treated) on Day 0 and exposed to sand flies approximately every 28 days up to Day 364. After each exposure, anti-feeding and fast-killing efficacy rates were determined by comparing blood-fed or live insects, respectively, in the treated vs. the control group. Blood-fed and live sand flies were significantly less in treated dogs as compared to control dogs at each assessment. The anti-feeding efficacy rate exceeded 90% except on Day 337 (89%) but increased again (96%) on Day 364. Fast killing efficacy was

Identification of Heterodera carotae (carrot cyst nematode), first reported from the Tarlton area in South Africa in 2008, was based on morphometrical and morphological characteristics. Specimens from this area were collected during the summer growing season of 2016 and identified using classical morphometrical and morphological techniques as well as molecular methods. The life cycle of this species was furthermore investigated in a carrot planting. Slight morphological differences were found between the Tarlton-population of H. carotae (South Africa) and its European, Canadian and Mexican counterparts. Second stage juveniles (J2) have a slightly shorter body (270.3–434 µm vs. 375–452 µm from those of Europe; 388–457 µm from Canada; and 360–443 µm from Mexico) and their heads are narrower (5.8–8.7 µm vs. 9–10 µm and 8–10 µm compared to that of specimens from Europe and Mexico, respectively). Spicules were slightly longer than that of both European and Canadian specimens (36.5–40.0 µm vs. 31–36 µm and 33–37 µm, respectively), but compared well with that of the Mexican males (36.5–40.0 µm vs. 32–39 µm). The male stylet is shorter (28.5–29.6 µm vs. 31–38 µm in European and 33–44 µm in Canadian specimens), but is nearer to that of Mexican specimens (28.5–29.6 µm vs. 29–36 µm). Novel golden-yellow cysts were observed. Phylogenetic analysis grouped the Tarlton population together in a clade with H. carotae, H. cruciferae and H. urticae. BLAST results indicated a 99% similarity with H. carotae. Heterodera carotae completed two life cycles during this growing season in Tarlton.

In the following systematic review and meta-analyses, we report several conclusions about resistance to carbapenem and polymyxin last-resort antibiotics for treating multidrug-resistant bacterial infections among pregnant women and infants. Resistance to carbapenems and polymyxins is increasing, even in otherwise vulnerable groups such as pregnant women, toddlers, and infants, for whom therapeutic options are limited. In almost all countries, carbapenem-/polymyxin-resistant Klebsiella pneumoniae, Escherichia coli, and Acinetobacter baumannii infect and/or colonize neonates and pregnant women, causing periodic outbreaks with very high infant mortalities. Downregulation of plasmid-borne blaNDM , blaKPC , blaOXA-48 , blaIMP, blaVIM , blaGES-5 , and ompK35/36 in clonal strains accelerates the horizontal and vertical transmissions of carbapenem resistance among these pathogens. New Delhi metallo-β-lactamase (NDM)-positive isolates in infants/neonates have been mainly detected in China and India, while OXA-48-positive isolates in infants/neonates have been mainly detected in Africa. NDM-positive isolates in pregnant women have been found only in Madagascar. Antibiotic therapy, prolonged hospitalization, invasive procedures, mechanical ventilation, low birth weight, and preterm delivery have been common risk factors associated with carbapenem/polymyxin resistance. The use of polymyxins to treat carbapenem-resistant infections may be selecting for resistance to both agents, restricting therapeutic options for infected infants and pregnant women. Currently, low- and middle-income countries have the highest burden of these pathogens. Antibiotic stewardship, periodic rectal and vaginal screening, and strict infection control practices in neonatal ICUs are necessary to forestall future outbreaks and deaths.

The polyphagous shothole borer (Euwallacea fornicatus, PSHB), an ambrosia beetle, with its fungal symbiont, Fusarium euwallaceae, is responsible for Fusarium dieback (FD) in a wide range of woody hosts. In 2019, the first suspected case of E. fornicatus was reported in macadamia in South Africa. The aims of this study were to confirm the E. fornicatus report and thereafter to assess the susceptibility of commercially planted macadamia cultivars to FD caused by F. euwallaceae. The identities of the beetle and associated fungal symbionts were confirmed by means of DNA sequence analysis of the 28S ribosomal large subunit gene for beetles and the internal transcribed spacer region for fungi. Isolates identified as Fusarium species were further characterized by phylogenetic analysis of the translation elongation factor 1α and the β-tubulin gene regions. Thereafter, Koch’s postulates regarding F. euwallaceae were fulfilled on a mature Macadamia integrifolia tree planted at the experimental farm of the University of Pretoria. In order to determine susceptibility against FD, additional cultivar screening was conducted on nine commercially planted cultivars by means of pathogenicity trials using sterilized or inoculated toothpicks inserted into detached branches. Detached branch inoculations showed no significant lesion development six weeks post inoculation, except for cultivar 816. The restricted growth of F. euwallaceae observed in macadamia tissues therefore suggests that macadamia may not be a suitable host for F. euwallaceae and that the threat of FD in macadamia in the event of E. fornicatus infestation is less than for other E. fornicatus hosts. Future work on beetle attraction to macadamia is recommended for a more comprehensive understanding of the interaction between E. fornicatus and its fungal symbionts and macadamia.

The reproduction potential of nine single-species Meloidogyne populations and 16 mixed-species communities, recovered from watermelon rhizospheres in South-West Nigeria, were determined in roots of tomato (cv. Tropimech) in a glasshouse. The host responses of six commercial watermelon cultivars were also assessed under glasshouse conditions to single-species populations of Meloidogyne incognita, M. javanica and M. enterolobii. Reproduction potential of different Meloidogyne populations and the host response of the cultivars were assessed based on the number of egg masses, final nematode population (Pf), reproduction factor (Rf) and relative susceptibility values (S%). No significant interaction (P

Summary Crop damage inflicted by Meloidogyne enterolobii justifies an updated literature review focusing on recent discoveries about its identification, biology and management. Since its description in 1983, M. enterolobii has become a pest of great concern, particularly due to its virulence, which renders controlling this nematode pest a challenge. The global distribution of M. enteroblii is summarised, with emphasis placed on limited research done for the species in sub-Saharan Africa where food production and security is threatened by root-knot nematode parasitism. Novel advances in methods used to detect M. enterolobii are touched upon, especially the improvement in advanced molecular techniques that complements shortcomings in morphology and morphometic approaches. Despite these exciting developments, the employment of effective management strategies to combat the species remains problematic. Future research on various aspects of M. enterolobii is crucial, with focus to be placed on the use of available resources to contain damage caused by this species.

The host status of South African adapted, genetically modified (GM) glyphosate-tolerant soybean genotypes to root-knot (field and glasshouse) and lesion (field) nematodes were assessed. Analyses of root and soil samples of 29 genotypes (collected from seven production areas during the 2014/15 season) enabled the identification of nine plant-parasitic nematode genera and 10 species. Predominant endoparasitic genera in root samples were Meloidogyne (Meloidogyne incognita and M. javanica) and Pratylenchus (Pratylenchus brachyurus, P. zeae and P. teres). Rotylenchulus parvus was the predominant semi-endoparasite in soil, followed by Scutellonema brachyurus and Helicotylenchus sp. Only ‘PAN 1583 R’ and ‘PAN 1521 R’ maintained less than 10% of the Meloidogyne spp. densities present in roots of the most susceptible genotype, while all genotypes were susceptible to the Pratylenchus spp. The host status of 36 soybean genotypes to M. incognita infection, evaluated in two follow-up glasshouse experiments terminated 56 days after inoculation of ca. 1000 M. incognita eggs and second-stage juveniles (J2) per seedling, varied substantially for final population density (Pf), reproduction factor (Rf) and relative percentage susceptibility (%S). Only ‘PRF-GCI7’ and the resistant reference ‘LS 5995’ had Rfs

International audience; Scientific communication is facilitated by a data-driven, scientifically sound taxonomy that considers the end-user's needs and established successful practice. Previously (Geiser et al. 2013; Phytopathology 103:400-408. 2013), the Fusarium community voiced near unanimous support for a concept of Fusarium that represented a clade comprising all agriculturally and clinically important Fusarium species, including the F. solani Species Complex (FSSC). Subsequently, this concept was challenged by one research group (Lombard et al. 2015 Studies in Mycology 80: 189-245) who proposed dividing Fusarium into seven genera, including the FSSC as the genus Neocosmospora, with subsequent justification based on claims that the Geiser et al. (2013) concept of Fusarium is polyphyletic (Sandoval-Denis et al. 2018; Persoonia 41:109-129). Here we test this claim, and provide a phylogeny based on exonic nucleotide sequences of 19 orthologous protein-coding genes that strongly support the monophyly of Fusarium including the FSSC. We reassert the practical and scientific argument in support of a Fusarium that includes the FSSC and several other basal lineages, consistent with the longstanding use of this name among plant pathologists, medical mycologists, quarantine officials, regulatory agencies, students and researchers with a stake in its taxonomy. In recognition of this monophyly, 40 species recently described as Neocosmospora were recombined in Fusarium, and nine others were renamed Fusarium. Here the global Fusarium community voices strong support for the inclusion of the FSSC in Fusarium, as it remains the best scientific, nomenclatural and practical taxonomic option available.

Information on the effect of the herbicide glyphosate on nematodes in the field is limited and contradictory. A small field experiment was conducted during two consecutive summer-growing seasons to investigate the response of plant-parasitic nematode communities on the application of glyphosate to genetically-modified glyphosate-tolerant soybean (cultivar ‘LS 6164 R’) and maize (cultivar ‘DKC 80-30 RR’). A mixed Meloidogyne incognita and Meloidogyne javanica population dominated both crops during both seasons. Five other plant-parasitic nematode genera (Criconema, Helicotylenchus, Nanidorus, Pratylenchus and Tylenchorhynchus) were also identified. Glyphosate application had no effect on M. incognita, M. javanica and Pratylenchus spp. numbers. No significant differences were observed between the glyphosate-treated and non-treated plots for Meloidogyne population densities per 50 g roots for both soybean and maize. Significant (p ≤ 0.05) differences recorded between glyphosate-treated and non-treated plots from 5 g roots and 200 g rhizosphere soil for other genera were mainly due to absence during some sampling dates

Summary Watermelon is increasingly produced and consumed in Nigeria and sub-Saharan Africa. However, limited information exists regarding nematode pests and beneficial/free-living nematodes associated with the crop. The present study recorded the abundance and diversity of free-living nematodes from 50 watermelon fields across south-west Nigeria during 2016/2017. Of the 30 genera identified from soil samples, Cephalobus, followed by Rhabditis, Aphelenchus and Aporcelaimus, were predominant. Variation in nematode community structures across the 50 fields was apparent for mean maturity indices, metabolic footprints, feeding-type composition and coloniser-persister (c-p) structure. Faunal analyses characterised 52% of the fields as having stable and enriched soil food webs, which is beneficial for crop production. Significant correlations were apparent between some nematode genera and selected soil properties, and rainfall. This study provides the first information of free-living nematodes associated with watermelon from sub-Saharan Africa, offering novel and baseline information on their abundance and diversity in south-west Nigeria.

Identification of Meloidogyne spp. is challenging when using only the classical techniques since some species share similar characteristics. In this study, 37 Meloidogyne populations were obtained from four provinces in South Africa during 2015 and 2016 and molecularly characterised. We used SCAR-PCR markers and sequencing of four DNA fragments, viz. the D2-D3 segment (28S rDNA), COI, viable region between COII and 16S rDNA and NADH5 (mtDNA) genes. Using SCAR-PCR, M. enterolobii, M. javanica, M. incognita and M. hapla (in descending order of prevalence) were identified. According to D2-D3, COI, COII/16S and NADH5 sequence analyses, the 23 M. enterolobii populations identified clustered together in a well-supported clade, while M. javanica (9 populations) and M. incognita (5 populations) grouped in another. Results showed that D2-D3 and COI genes were appropriate for accurate identification of M. enterolobii, but not to differentiate among M. arenaria, M. incognita and M. javanica. Conversely, SCAR-PCR and NADH5 were more accurate in distinguishing among different Meloidogyne spp. In conclusion, SCAR-PCR was best for the situation of mixed populations.

Dry bean (Phaseolus vulgaris L.) is grown under an extensive range of agro-climatic conditions and is an essential source of protein and income globally. This study aimed to evaluate yield performance, stability, and bacterial brown spot (BBS) disease resistance of fourteen dark red kidney genotypes across environments in South Africa namely Carolina, Clarens, Cedara, Middelburg, Potchefstroom, and Warden. Analysis of variance (ANOVA), additive main effects and multiplicative interaction (AMMI) and the genotype plus genotype by environment interaction (GGE-biplot) analysis were used to evaluate grain yield performance, stability, and BBS disease resistance. The AMMI ANOVA revealed that mean squares for grain yield and BBS severity for the environment, genotype, and genotype by environment interaction were highly significant (P

Bacterial brown spot (BBS) disease caused by Pseudomonas syringae pv. syringae is an important disease of dry bean (Phaseolus vulgaris L.), with grain yield losses of 55% reported in South Africa. This study aimed to identify BBS disease-resistant genotypes from 415 Andean Diversity Panel (ADP) dry bean lines and 5 check cultivars under field conditions across three sites in South Africa: Warden and Middelburg under natural infestation and Potchefstroom under artificial inoculation. Plants at Potchefstroom were inoculated with P. syringae pv. syringae using three isolates at 21, 28, and 36 days after planting, and disease scoring was done at 7, 14, and 21 days after inoculation following a modified 1 to 9 International Centre for Tropical Agriculture (CIAT) scale. The BBS severity percentage and the area under the disease progress curve (AUDPC) were applied to quantify the reaction of bean genotypes to BBS disease. The study identified 17.2% of evaluated germplasm as resistant and 45.3% as moderately resistant. Genotypes ADP-0592, ADP-0790, ADP-0120, and ADP-0008 were selected for both resistance and high seed yield across the three environments. Genotypes ADP-0546, ADP-0630, ADP-0120, and ADP-0279 were selected for both high yield and resistance at Warden, whereas ADP-0038, ADP-0721, and ADP-0790 were selected for both traits at Middelburg, and lastly, ADP-0120 and ADP-0079 were selected for both traits at Potchefstroom. The best genotypes selected for both high yield and BBS resistance had grain yield >1.45 t ha−1 across sites and >1.85 t ha−1 at individual sites, and they out yielded the best-performing check cultivar (1.13 t ha−1) and the grand mean yield (0.87 t ha−1) across sites. The AUDPC had a strong negative correlation (r = −0.55, P < 0.001) with grain yield at Potchefstroom. Medium-seeded genotypes showed a lower AUDPC than the large-seeded genotypes, and indeterminate genotypes showed a lower AUDPC than determinate genotypes. The genotypes selected for resistance and yield can be utilized in future dry bean improvement efforts for the South African bean market.

Candida albicans is an opportunistic yeast pathogen within the human microbiota with significant medical importance because of its pathogenic potential. The yeast produces highly resistant biofilms, which are crucial for maintaining infections. Though antifungals are available, their effectiveness is dwindling due to resistance. Alternate options that comprise the combination of existing azoles and polyunsaturated fatty acids, such as arachidonic acid (AA), have been shown to increase azoles susceptibility of C. albicans biofilms; however, the mechanisms are still unknown. Therefore, transcriptome analysis was conducted on biofilms exposed to sub-inhibitory concentrations of AA alone, fluconazole alone, and AA combined with fluconazole to understand the possible mechanism involved with the phenomenon. Protein ANalysis THrough Evolutionary Relationships (PANTHER) analysis from the differentially expressed genes revealed that the combination of AA and fluconazole influences biological processes associated with essential processes including methionine synthesis and those involved in ATP generation, such as AMP biosynthesis, fumarate metabolism and fatty acid oxidation. These observations suggests that the interference of AA with these processes may be a possible mechanisms to induce increased antifungal susceptibility.

Clinical specimens unfit for laboratory processing represent missed opportunities for diagnosing tuberculosis. Poor-quality cough specimens (n=61) from presumptive tuberculosis cases were cultured and GeneXpert MTB/RIF (Xpert) successfully performed on samples transferred by flocked swab into PrimeStore molecular transport medium (PS-MTM). Mycobacterium tuberculosis was grown in culture from 13 (21.3 %) and Xpert reported 15 (24.2 %) positive, of which 10 concordant. RT-PCR of PS-MTM samples showed enhanced sensitivity; three positives were missed by Xpert, five by culture and three more detected for a total of 21 positives (34.4 %).

Alphaviruses from Africa, such as Middelburg virus (MIDV), and Sindbis virus (SINV), were detected in horses with neurologic disease in South Africa, but their host ranges remain unknown. We investigated the contribution of alphaviruses to neurologic infections and death in wildlife and domestic animals in this country. During 2010-2018, a total of 608 clinical samples from wildlife and nonequine domestic animals that had febrile, neurologic signs or unexplained deaths were tested for alphaviruses. We identified 32 (5.5%) of 608 alphavirus infections (9 SINV and 23 MIDV), mostly in neurotissue of wildlife, domestic animals, and birds. Phylogenetic analysis of the RNA-dependent RNA polymerase gene confirmed either SINV or MIDV. This study implicates MIDV and SINV as potential causes of neurologic disease in wildlife and nonequine domestic species in Africa and suggests a wide host range and pathogenic potential.

Citrus tatter leaf virus (CTLV), a strain of apple stem grooving virus, is a virus of citrus that is of commercial importance for trifoliate orange (Poncirus trifoliata) and trifoliate hybrid rootstocks. Bud-union crease is a CTLV-induced incompatibly symptom observed with these rootstocks and citrus scions which results in stunted tree growth. CTLV is a regulated pathogen for most citrus budwood certification programs worldwide. Due to the requisite virus testing, commercially supplied scion budwood would therefore seldom be a point of contamination. However, citrus rootstocks are primarily propagated by seed and the potential for seed transmission of CTLV in citrus is unclear and remains a potential source of infection. A single, unconfirmed report of seed transmission of CTLV in ‘Eureka’ lemon (Citrus × limon) exists, and although this report was not of a rootstock cultivar, it does point to the risk of seed transmission in citrus and close relatives in the family Rutaceae. CTLV-positive ‘Meyer’ lemon (C. × limon) trees in an experimental plot in the Eastern Cape Province of South Africa presented an opportunity to again test seed transmission in citrus. Seed was obtained from the infected ‘Meyer’ lemon trees, and 1164 seedlings were grown in an insect-secure greenhouse and screened for CTLV in pooled batches by conventional and real-time RT-PCR. No positive samples were detected and results indicated a lack of virus seed transmission in ‘Meyer’ lemon. Findings of this study are therefore not supportive of CTLV seed transmission in citrus.

The genus Calonectria includes many important plant pathogens with a wide global distribution. In order to better understand the reproductive biology of these fungi, we characterised the structure of the mating type locus and flanking genes using the genome sequences for seven Calonectria species. Primers to amplify the mating type genes in other species were also developed. PCR amplification of the mating type genes and multi-gene phylogenetic analyses were used to investigate the mating strategies and evolution of mating type in a collection of 70 Calonectria species residing in 10 Calonectria species complexes. Results showed that the organisation of the MAT locus and flanking genes is conserved. In heterothallic species, a novel MAT gene, MAT1-2-12 was identified in the MAT1-2 idiomorph;the MAT1-1 idiomorph, in most cases, contained the MAT1-1-3 gene. Neither MAT1-1-3 nor MAT1-2-12 was found in homothallic Calonectria (Ca.) hongkongensis, Ca. lateralis, Ca. pseudoturangicola and Ca. turangicola. Four different homothallic MAT locus gene arrangements were observed. Ancestral state reconstruction analysis provided evidence that the homothallic state was basal in Calonectria and this evolved from a heterothallic ancestor.

Increasingly, gut microbiota distortions are being implicated in the pathogenesis of several infectious and noninfectious diseases. Specifically, in the absence of an eubiotic microbiota, mice are more prone to colonization and infection by Mycobacterium tuberculosis (Mtb). In this qualitative analysis, the following were observed: (1) antimicrobials cause long-term gut microbiota perturbations; (2) Mtb causes limited and transient disturbances to the lung-gut microbiota; (3) pathogens (e.g., Helicobacter hepaticus) affect microbiota integrity and reduce resistance to Mtb; (4) dysbiosis depletes bacterial species regulating proper immune functioning, reducing resistance to Mtb; (5) dysregulated immune cells fail to express important pathogen-recognition receptors (e.g., macrophage-inducible C-type lectin; MINCLE) and Mtb-killing cytokines (e.g., IFN-γ, TNF-α, and IL-17), with hampered phagocytic capability; (6) autophagy is central to the immune system's clearance of Mtb, control of inflammation, and immunity-microbiome balance; (7) microbiota-produced short-chain fatty acids, which are reduced by dysbiosis, affect immune cells and increase Mtb proliferation; (8) commensal species (e.g., Lactobacillus plantarum) and microbiota metabolites (e.g., indole propionic acid) reduce tuberculosis progression; and (9) fecal transplants mostly restored eubiosis, increased immune resistance to Mtb, restricted dissemination of Mtb, and reduced tuberculosis-associated organ pathologies. Overuse of antimicrobials, as shown in mice, is a risk factor for reactivating latent or treated tuberculosis.

In November 2018 the governor of Dar es Salaam, Tanzania, launched an anti-gay crackdown, threatening the arrest of individuals suspected of being homosexual. Of the 54 countries in Africa, 34 curr...

Wilt and death of an E. grandis × E. urophylla variety was recently observed in the Zululand region of KwaZulu- Natal, South Africa. Symptoms on the dying trees included a streaking pattern of disc...

In the summer of 2018, specimens of a Hoplolaimus population were extracted from a maize root sample collected near Stampriet, Namibia. This population was identified as Hoplolaimus pararobustus and is described and illustrated based on its morphological, morphometric, and molecular characteristics. To our knowledge, this is the first report H. pararobustus from maize roots. Females of the population had a mean body and stylet length of 1,100 µm and 36 µm, respectively. Esophagus with three nuclei in three pharyngeal glands. Lateral field reduced, ranging from a very faint line to just breaks in striae. The males were shorter than the females with a mean body length of 925 µm and the stylet slightly shorter, with a mean length of 34 µm. Phylogenetic analyses using partial sequences of 18 S and the expansion fragment D2–D3 of 28 S rDNA genes showed the close relation of this species and H. columbus. This Namibian population of H. pararobustus is the first Hoplolaimus species from Africa to be molecularly characterized.

Made available in DSpace on 2022-05-01T10:19:00Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-12-01 Background: Arthropod-borne pathogens and their vectors are present throughout Africa. They have been well-studied in livestock of sub-Saharan Africa, but poorly in companion animals. Given the socio-economic importance of companion animals, the African Small Companion Animal Network (AFSCAN), as part of the WSAVA Foundation, initiated a standardized multi-country surveillance study. Methods: Macro-geographic variation in ectoparasite (ticks and fleas) and pathogen communities in dogs was assessed through molecular screening of approximately 100 infested dogs in each of six countries (Ghana, Kenya, Nigeria, Tanzania, Uganda and Namibia), both in rural and urban settings. The most important intrinsic and extrinsic risk factors within the subpopulation of infested dogs were evaluated. Results: Despite the large macro-geographic variation in the dogs screened, there was no consistent difference between East and West Africa in terms of the diversity and numbers of ticks. The highest and lowest numbers of ticks were found in Nigeria and Namibia, respectively. Most often, there was a higher diversity of ticks in rural habitats than in urban habitats, although the highest diversity was observed in an urban Uganda setting. With the exception of Namibia, more fleas were collected in rural areas. We identified tick species (including Haemaphysalis spinulosa) as well as zoonotic pathogens (Coxiella burnetti, Trypanosoma spp.) that are not classically associated with companion animals. Rhipicephalus sanguineus was the most abundant tick, with a preference for urban areas. Exophilic ticks, such as Haemaphysalis spp., were more often found in rural areas. Several multi-host ticks occurred in urban areas. For R. sanguineus, housing conditions and additional pets were relevant factors in terms of infestation, while for a rural tick species (Haemaphysalis elliptica), free-roaming dogs were more often infested. Tick occurrence was associated to the use of endoparasiticide, but not to the use of ectoparasiticide. The most prevalent tick-borne pathogen was Hepatozoon canis followed by Ehrlichia canis. High levels of co-parasitism were observed in all countries and habitats. Conclusions: As dogs share a common environment with people, they have the potential to extend the network of pathogen transmission to humans. Our study will help epidemiologists to provide recommendations for surveillance and prevention of pathogens in dogs and humans. Graphical abstract: [Figure not available: see fulltext.]. Eco-Epidemiology Group Department of Biomedical Sciences Institute of Tropical Medicine Interuniversity Institute for Biostatistics and Statistical Bioinformatics Hasselt University Department of Ecology and Evolutionary Biology Princeton University School of Veterinary and Life Sciences Murdoch University Bayer Animal Health Elanco Animal Health Inc. Clinvet LLC ClinVet International (Pty) Ltd. Clinomics School of Veterinary Medicine College of Basic and Applied Sciences (CBAS) University of Ghana Department of Veterinary Pathology Microbiology and Parasitology University of Nairobi Department of Veterinary Parasitology and Entomology College of Veterinary Medicine Federal University of Agriculture Sokoine University of Agriculture Research Center for Tropical Diseases and Vector Control College of Veterinary Medicine Animal Resources and Biosecurity Makerere University School of Veterinary Medicine University of Namibia, Neudamm São Paulo State University University of Pretoria Clinglobal São Paulo State University

Parasites threaten human and animal health globally. It is estimated that more than 60% of people on planet Earth carry at least one parasite, many of them several different species. Unfortunately, parasite studies suffer from duplications and inconsistencies between different investigator groups. Hence, groups need to collaborate in an integrated manner in areas including parasite control, improved therapy strategies, diagnostic and surveillance tools, and public awareness. Parasite studies will be better served if there is coordinated management of field data and samples across multidisciplinary approach plans, among academic and non-academic organizations worldwide. In this paper we report the first 'Living organism-World Molecular Network', with the cooperation of 167 parasitologists from 88 countries on all continents. This integrative approach, the 'Sarcoptes-World Molecular Network', seeks to harmonize Sarcoptes epidemiology, diagnosis, treatment, and molecular studies from all over the world, with the aim of decreasing mite infestations in humans and animals. © 2011 International Society for Infectious Diseases.

Objectives: The PartneRships in cOngeniTal hEart disease (PROTEA) project aims to establish a densely phenotyped and genotyped Congenital Heart Disease (CHD) cohort for southern Africa. This will facilitate research into the epidemiology and genetic determinants of CHD in the region. This paper introduces the PROTEA project, characterizes its initial cohort, from the Western Cape Province of South Africa, and compares the proportion or “cohort-prevalences” of CHD-subtypes with international findings.Methods: PROTEA is a prospective multicenter CHD registry and biorepository. The initial cohort was recruited from seven hospitals in the Western Cape Province of South Africa from 1 April 2017 to 31 March 2019. All patients with structural CHD were eligible for inclusion. Descriptive data for the preliminary cohort are presented. In addition, cohort-prevalences (i.e., the proportion of patients within the cohort with a specific CHD-subtype) of 26 CHD-subtypes in PROTEA's pediatric cohort were compared with the cohort-prevalences of CHD-subtypes in two global birth-prevalence studies.Results: The study enrolled 1,473 participants over 2 years, median age was 1.9 (IQR 0.4–7.1) years. Predominant subtypes included ventricular septal defect (VSD) (339, 20%), atrial septal defect (ASD) (174, 11%), patent ductus arteriosus (185, 11%), atrioventricular septal defect (AVSD) (124, 7%), and tetralogy of Fallot (121, 7%). VSDs were 1.8 (95% CI, 1.6–2.0) times and ASDs 1.4 (95% CI, 1.2–1.6) times more common in global prevalence estimates than in PROTEA's pediatric cohort. AVSDs were 2.1 (95% CI, 1.7–2.5) times more common in PROTEA and pulmonary stenosis and double outlet right ventricle were also significantly more common compared to global estimates. Median maternal age at delivery was 28 (IQR 23–34) years. Eighty-two percent (347/425) of mothers used no pre-conception supplementation and 42% (105/250) used no first trimester supplements.Conclusions: The cohort-prevalence of certain mild CHD subtypes is lower than for international estimates and the cohort-prevalence of certain severe subtypes is higher. PROTEA is not a prevalence study, and these inconsistencies are unlikely the result of true differences in prevalence. However, these findings may indicate under-diagnosis of mild to moderate CHD and differences in CHD management and outcomes. This reemphasizes the need for robust CHD epidemiological research in the region.

Background: Shank genes are implicated in ~1% of people with autism and mice with Shank3 knock out mutations exhibit autism-like behaviours. Zinc deficiency and gastrointestinal problems can be common among people with autism, and zinc is a key element required for SHANK protein function and gut development. In Shank3B-/- mice, a supplementary zinc diet reverses autism behaviours. We hypothesise that dietary zinc may alter the gut microbiome, potentially affecting the gut-microbiota-brain axis, which may contribute to changes in autism-like behaviours. Methods: Four types of gastrointestinal samples (ileum, caecum, colon, faecal) were collected from wild-type and knock-out Shank3B-/- mice on either control or supplemented-zinc diets. Bacterial 16S rRNA gene and fungal ITS2 genomic region amplicons were sequenced on the Illumina MiSeq platform and RNA on the Illumina HiSeq platform.Results: Cage, genotype and zinc diet each contributed significantly to bacterial community variation (accounting for 12.8%, 3.9% and 2.3% of the variation, respectively). Fungal diversity differed significantly between wild-type and knock-out Shank3B-/- mice on the control zinc diet, and the fungal biota differed among gut locations. RNA-seq analysis of host (mouse) transcripts revealed differential expression of genes involved in host metabolism that may be regulated by the gut microbiota and genes involved in anti-microbial interactions. Limitations: This study used the Shank3B-/- mouse model of autism spectrum disorder. Heterozygous and homozygous Shank3 gene mutations are found in 1% of the ASD population, only homozygous Shank3 mice were utilised in this study. Any translational conclusions should consider these limitations.Conclusions: By utilising the Shank3B-/- knock-out mouse model we were able to examine the influence of – and interactions between – dietary zinc and ASD-linked host genotype. Differential expression of host antimicrobial interaction genes as well as gut microbiota-regulated host metabolism genes among the treatment groups, suggests that the interplay between gut microbes, the gastrointestinal tract and the brain may play a major role towards the observed amelioration of ASD behaviours seen previously with supplemented dietary zinc. These data broaden understanding of the gut microbiome in autism and pave the way towards potential microbial therapeutics for gastrointestinal problems in people with autism.

Summary Little information is available for nematode pests associated with watermelon in sub-Saharan Africa (SSA). This study recorded the abundance and prevalence of plant-parasitic nematodes from 25 localities across south-west Nigeria during 2016/2017. Of the 11 nematode species identified, those belonging to Meloidogyne spp. were predominant according to Prominence Values, followed by Helicotylenchus dihystera, Pratylenchus zeae and Scutellonema bradys. Morphological and molecular analyses revealed the identity of four species of root-knot nematodes: Meloidogyne enterolobii, M. incognita, M. javanica and M. arenaria (in descending order of abundance and occurrence). Meloidogyne arenaria is reported for the first time from south-west Nigeria, while S. bradys and Xiphinema nigeriense are first reports for watermelon. Significant associations were observed between the frequency of occurrence of the predominant nematode species and soil properties as well as rainfall. Results provide baseline information on the nematode pest occurrence on watermelon in Nigeria and in a wider context for SSA.

With an increase in the global population, a protein-rich crop like soybean can help manage food insecurity in sub-Saharan Africa (SSA). The expansion of soybean production in recent years lead to increased land requirements for growing the crop and the increased risk of exposing this valuable crop to various pests and diseases. Of these pests, plant-parasitic nematodes (PPN), especially Meloidogyne and Pratylenchus spp., are of great concern. The increase in the population densities of these nematodes can cause significant damage to soybean. Furthermore, the use of crop rotation and cultivars (cvs.) with genetic resistance traits might not be effective for Meloidogyne and Pratylenchus control. This review builds on a previous study and focuses on the current nematode threat facing local soybean production, while probing into possible biological control options that still need to be studied in more detail. As soybean is produced on a global scale, the information generated by local and international researchers is needed. This will address the problem of the current global food demand, which is a matter of pressing importance for developing countries, such as those in sub-Saharan Africa.

Soil amendments, constituting of various plant and animal sources, were evaluated in pits for their effects on Meloidogyne spp. infecting tomato in comparison to the synthetic nematicide fenamiphos and the untreated control. Fifty-six days after transplanting, soil and root samples were collected for nematode extraction and counting while fruit mass and the number of fruits were also recorded and the average yield per treatment calculated. The plant-based pit-composting treatments decreased nematode population densities, from 43% to 94%; with the citrus fruit-pit compost being the most effective (reducing nematode densities by up to 94%). Conversely, chicken and cattle manure treatments generally resulted in increased nematode densities (up to 141% and 159%, respectively). Increases in tomato yield ranged from 7% to 94% in response to compost, cattle and chicken manure treatments while all pit-composting significantly enhanced yield ranging from 100% to 400%; except for the shrub-pruning pit compost which decreased yield. Pit-composting is a promising strategy that can be used by especially subsistence farmers to grow crops sustainably in the presence of lower nematode pest densities

Summary A new species of Aporcelaimellus, collected in a watermelon field in Nigeria, is described, including its morphological and molecular (D2-D3 28S-rDNA, 18r-DNA) characterisation. Aporcelaimellus nigeriensis sp. n. is distinguishable by its 2.76-3.55 mm length, very coarse ventral body pores, lip region offset by deep constriction and 24-27 μm broad odontostyle 30-36 μm long at its dorsal and 28-31 μm at its ventral side, neck 648-779 μm long, pharyngeal expansion occupying 54-60% of total neck length, uterus 300-473 μm or 2.1-3.2 body diam. long and tripartite, V = 49-54, tail short and convex conoid (27-41 μm, c = 72-115, c′ = 0.5-0.7), spicules 108-137 μm long, and 9-10 spaced ventromedian supplements with hiatus. LSU analysis revealed a close relationship of A. nigeriensis sp. n. with other Aporcelaimellus species and questioned, once more, the monophyly of Aporcelaimidae. SSU phylogenetic tree was not able to resolve the relationship between the new species and other closely related species.

Caenorhabditis elegans presents functioning, biologically relevant phenotypes and is frequently used as a bioindicator of toxicity. However, most C. elegans in vivo effect-assessment methods are laborious and time consuming. Therefore, we developed a novel method to measure the oxygen consumption rate of C. elegans as a sublethal endpoint of toxicity. This protocol was tested by exposing 50 larval stage one C. elegans individuals for 48 h (at 20 °C) to different concentrations of two toxicants i.e. benzylcetyldimethylammonium chloride (BAC-C16) and cadmium (Cd). Following exposures, the oxygen consumption rate of the C. elegans individuals were measured using the high-throughput functionality of the Seahorse XFe96 Extracellular Flux Analyzer. Dose-response curves for BAC-C16 (R2 = 0.93; P = 0.001) and Cd (R2 = 0.98; P = 0.001) were created. Furthermore, a strong, positive correlation was evidenced between C. elegans oxygen consumption rate and a commonly used, ecologically relevant endpoint of toxicity (growth inhibition) for BAC-C16 (R2 = 0.93; P = 0.0001) and Cd (R2 = 0.91; P = 0.0001). The data presented in this study show that C. elegans oxygen consumption rate can be used as a promising functional measurement of toxicity.

Soybean is among South Africa’s top crops in terms of production figures. Over the past few years there has been increasingly more damage caused to local soybean by plant-parasitic nematode infections. The presence of Meloidogyne (root-knot nematodes) and Pratylenchus spp. (root lesion nematodes) in soybean fields can cripple the country’s production, however, little is known about the soil microbial communities associated with soybean in relation to different levels of Meloidogyne and Pratylenchus infestations, as well as the interaction(s) between them. Therefore, this study aimed to identify the nematode population assemblages and endemic rhizosphere bacteria associated with soybean using Next Generation Sequencing (NGS). The abundance of bacterial genera that were then identified as being significant using linear discriminant analysis (LDA) Effect Size (LEfSe) was compared to the abundance of the most prevalent plant-parasitic nematode genera found across all sampled sites, viz. Meloidogyne and Pratylenchus. While several bacterial genera were identified as significant using LEfSe, only two with increased abundance were associated with decreased abundance of Meloidogyne and Pratylenchus. However, six bacterial genera were associated with decreased Pratylenchus abundance. It is therefore possible that endemic bacterial strains can serve as an alternative method for reducing densities of plant-parasitic nematode genera and in this way reduce the damages caused to this economically important crop.

The nonpolar lipids present in cells are mainly triacylglycerols and steryl esters. When cells are provided with an abundance of nutrients, these storage lipids accumulate. As large quantities of nonpolar lipids cannot be integrated into membranes, they are isolated from the cytosolic environment in lipid droplets. As specialized, inducible cytoplasmic organelles, lipid droplets have functions beyond the regulation of lipid metabolism, in cell signalling and activation, membrane trafficking and control of inflammatory mediator synthesis and secretion. Pathogens, including fungi, viruses, parasites, or intracellular bacteria can induce and may benefit from lipid droplets in infected cells. Here we review biogenesis of lipid droplets as well as the role of lipid droplets in the pathogenesis of selected viruses, bacteria, protists and yeasts.

BackgroundDiagnostics for tuberculosis (TB) and treatment monitoring remains a challenge, particularly in less-resourced laboratories. Further, the comprehensive sputum microbiota of TB patients during treatment are less described, particularly using long-read sequencers.MethodsDNA from sputum samples collected from newly-diagnosed TB patients were sequenced with Oxford Nanopore’s MinION. MG-RAST and R packages (Phyloseq, α/β diversities, functional components, OTUs networks and ordination plots. Statistical significance of the generated data was determined using GraphPad.Results & conclusionAntibiotics reduced the abundance and functional subsystems of each samples’ microbiota from baseline until day 7, when persistent, tolerant, and resistant microbiota, including fungi, grew back again. Variations in microbiota abundance and diversity were patient-specific. Closer microbiome network relationships observed in baseline samples reduced until day 7, when it became closer again. Bacterial microbiota networks and spatial ordination relationships were closer than that of other kingdoms. Actinobacteria phylum and Mycobacterium were more affected by antibiotics than other phyla and genera. Parasites, viruses, and fungi were less affected by antibiotics than bacteria in a descending order. Resistance genes/mechanisms to important antibiotics, plasmids, transposons, insertion sequences, integrative conjugative elements were identified in few samples.MinION can be adopted clinically to monitor treatment and consequent dysbiosis, and identify both known and unknown pathogens and resistance genes to inform tailored treatment choices, specifically in TB.Author summaryTuberculosis (TB), one of the major killers of mankind, continually remains elusive as challenges with early diagnosis and treatment monitoring remain. Herein, we use a single portable sequencer from Oxford Nanopore, the minION, to diagnose TB and monitor its treatment with antibiotics using routine sputum samples. In addition, the presence of other pathogens, important commensals, antibiotic resistance genes, mobile genetic elements, and the effect of the antibiotic treatment on the sputum microbiota were determined from the same data. This makes the minION an important tool that can be used in clinical laboratories to obtain data that can inform live-saving decisions.

The yeast Candida albicans exhibits multiple morphologies dependent on environmental cues. Candida albicans biofilms are frequently polymicrobial, enabling interspecies interaction through proximity and contact. The interaction between C. albicans and the bacterium, Pseudomonas aeruginosa, is antagonistic in vitro, with P. aeruginosa repressing the yeast-to-hyphal switch in C. albicans. Previous transcriptional analysis of C. albicans in polymicrobial biofilms with P. aeruginosa revealed upregulation of genes involved in regulation of morphology and biofilm formation, including SET3, a component of the Set3/Hos2 histone deacetylase complex (Set3C). This prompted the question regarding the involvement of SET3 in the interaction between C. albicans and P. aeruginosa, both in vitro and in vivo. We found that SET3 may influence early biofilm formation by C. albicans and the interaction between C. albicans and P. aeruginosa. In addition, although deletion of SET3 did not alter the morphology of C. albicans in the presence of P. aeruginosa, it did cause a reduction in virulence in a Caenorhabditis elegans infection model, even in the presence of P. aeruginosa.

Background The southern African yellow dog tick, Haemaphysalis elliptica, occurs in eastern and southern Africa and adults infest domestic and wild carnivores. This tick species is also a vector of the highly virulent Babesia rossi pathogen, the causative agent of canine babesiosis in sub-Saharan Africa. Sustained high levels of efficacy of a parasiticide are not only important in protecting dogs against the direct effects of tick infestation, but also in reducing the risk of tick-borne diseases. Sarolaner (Simparica™ chewable tablets) has been reported to be effective against the major tick species infesting dogs in Europe and the USA, including representatives from the genera Amblyomma, Ixodes, Rhipicephalus and Dermacentor. Until now no efficacy evaluations have been reported against species of the genus Haemaphysalis. The objective of the study was to confirm the efficacy of a single 2 mg sarolaner/kg oral dose of Simparica™ against induced infestations with H. (R.) elliptica, an important parasite of dogs in southern Africa. Methods This blinded, randomised, single centre, placebo controlled efficacy study followed a parallel group design and was conducted on two groups consisting of eight purpose-bred dogs each. Animals were treated orally, once on Day 0, with either a placebo compound (Group 1) or Simparica™ (Group 2). Simparica™ was administered orally at a dose rate of 2 mg sarolaner/kg body weight. The dogs were infested with ticks on Days − 7, − 2, 5, 12, 19, 26 and 33, with removal counts conducted on Days − 5, 2, 7, 14, 21, 28 and 35. Results A single oral administration of Simparica™ (sarolaner) at a minimum dose of 2 mg/kg resulted in a 100% efficacy against existing infestations of H. (R.) elliptica on dogs and a 100% reduction in live ticks following weekly re-infestations for 35 days. Moreover, the immediate and persistent high levels of efficacy observed in this study for 35 days is consistent with those observed in previous studies against ticks in other genera. Conclusions The efficacy of sarolaner (Simparica™), administered orally to dogs at the minimum label dose of 2.0 mg/kg, was demonstrated against existing and weekly re-infestations of H. (R.) elliptica for at least 5 weeks. Efficacy of 100% was achieved against existing infestations as well as weekly re-infestations.

Background In-field measurement of yield and growth rate in pasture species is imprecise and costly, limiting scientific and commercial application. Our study proposed a LiDAR-based mobile platform for non-invasive vegetative biomass and growth rate estimation in perennial ryegrass (Lolium perenne L.). This included design and build of the platform, development of an algorithm for volumetric estimation, and field validation of the system. The LiDAR-based volumetric estimates were compared against fresh weight and dry weight data across different ages of plants, seasons, stages of regrowth, sites, and row configurations. Results The project had three phases, the last one comprising four experiments. Phase 1: a LiDAR-based, field-ready prototype mobile platform for perennial ryegrassrecognition in single row plots was developed. Phase 2: real-time volumetric data capture, modelling and analysis software were developed and integrated and the resultant algorithm was validated in the field. Phase 3. LiDAR Volume data were collected via the LiDAR platform and field-validated in four experiments. Expt.1: single-row plots of cultivars and experimental diploid breeding populations were scanned in the southern hemisphere spring for biomass estimation. Significant (P

Cardiospermum grandiflorum (Balloon vine), a subtropical climber native to America, is rapidly increasing in importance as an invasive environmental weed in South Africa. It is a vigorous climber which invades forest margins and watercourses in sub-tropical areas such as coastal KwaZulu-Natal and Mpumalanga. Robust stems with tendrils enable C. grandiflorum to climb trees and form a dense canopy, completely smothering the underlying indigenous vegetation. Consequently it was targeted for biological control. The microcyclic rust fungus Puccinia arechavaletae was collected from Misiones, Argentina, and established under quarantine conditions in South Africa. Host specificity testing was carried out in the quarantine facilities. A total of 19 plant species were inoculated with the rust fungus, including representatives of 13 genera in the Sapindaceae which are native to southern Africa, three cultivars of the important crop plant Litchi chinensis, and all members of Cardiospermum that occurs in southern Africa. Other than C. grandiflorum, only C. corindum (of South African origin), C. pechuelii (native to Namibia), and C. halicacabum var. halicacabum (introduced weed in South Africa) were susceptible. Occasionally pustules developed on Allophylus natalensis, Dodonaea viscosa and Paullinia pinnata, but these are considered to be the result of the artificial high inoculum loads employed and not representing a susceptible host response. It is necessary to undertake a risk assessment of the potential risk posed to C. corindum and C. pechuelii before P. arechavaletae will be considered for the release as a biocontrol agent against balloon vine in South Africa.

Producción Científica, Fusarium circinatum is a harmful pathogenic fungus mostly attacking Pinus species and also Pseudotsuga menziesii, causing cankers in trees of all ages, damping-of in seedlings, and mortality in cuttings and mother plants for clonal production. This fungus is listed as a quarantine pest in several parts of the world and the trade of potentially contaminated pine material such as cuttings, seedlings or seeds is restricted in order to prevent its spread to disease-free areas. Inspection of plant material often relies on DNA testing and several conventional or real-time PCR based tests targeting F. circinatum are available in the literature. In this work, an international collaborative study joined 23 partners to assess the transferability and the performance of nine molecular protocols, using a wide panel of DNA from 71 representative strains of F. circinatum and related Fusarium species. Diagnostic sensitivity, specifcity and accuracy of the nine protocols all reached values >80%, and the diagnostic specifcity was the only parameter difering signifcantly between protocols.The rates of false positives and of false negatives were computed and only the false positive rates difered signifcantly, ranging from 3.0% to 17.3%.The diference between protocols for some ofthe performance values were mainly due to cross-reactions with DNA from non-target species, which were either not tested or documented in the original articles. Considering that participating laboratories were free to use their own reagents and equipment, this study demonstrated that the diagnostic protocols for F. circinatum were not easily transferable to endusers. More generally, our results suggest that the use of protocols using conventional or real-time PCR outside their initial development and validation conditions should require careful characterization of the performance data priorto use under modifed conditions (i.e. reagents and equipment). Suggestions to improve the transfer are proposed., European Cooperation in Science and Technology (COST Action FP1406 PINESTRENGTH), Estonian Science Foundation (grants PSG136 and IUT21-04), Centro de Estudios do Ambiente e do Mar (CESAM) (projects UID/AMB/50017/2013 and POCI-01- 0145- FEDER-007638), Slovenian Research Agency (project P4-0107)

Background The interplay of speed of activity of acaricidal products and tick-borne pathogen transmission time is the major driver for disease prevention. This study aimed to investigate the time required for transmission of Anaplasma phagocytophilum by adult Ixodes ricinus ticks in vivo on dogs, and to confirm the time required for transmission observed in vivo, in vitro. Methods Nymphs of I. ricinus were experimentally infected with an A. phagocytophilum strain of canine origin. Dogs were allocated to 6 groups of 3 dogs each. Groups 1–5 were infested with 50 A. phagocytophilum-infected female adult ticks on Day 0. Ticks were removed post-infestation at 3, 6, 12, 24 and 48 h. Dogs in Group 6 were infested with 60 A. phagocytophilum-infected female adult ticks (left on dogs until engorged). Dogs were observed daily for general health and clinically examined on Day 0, and weekly from Day 14. Blood was collected for qPCR and serological analysis on Day 0 (pre-challenge) and weekly thereafter. In the in vitro study each artificial feeding chamber was seeded with 10 adult ticks (5 male/5 female), attachment assessed, and blood pools sampled for qPCR at 6 h intervals up to 72 h after first tick attachment. Results Anaplasma phagocytophilum specific antibodies and DNA were detected in all 3 dogs in Group 6. No A. phagocytophilum-specific antibodies or DNA were detected in any dogs in Groups 1–5. All dogs remained healthy. Female tick attachment in 60 artificial feeding chambers over 72 h ranged between 20–60%. Anaplasma phagocytophilum DNA was detected in the blood collected from 5% of chambers sampled at 6 h, with the highest number of positive samples (16.3%) observed at 36 h. Conclusions Transmission of A. phagocytophilum by I. ricinus ticks starts within a few hours after attachment but establishment of infections in dogs is apparently dependent on a minimum inoculation dose that was only observed when ticks attached for greater than 48 h. These findings highlight the need for acaricidal products to exert a repellent and/or rapid killing effect on ticks to forestall transmission and subsequent disease.

African leafy vegetables (ALVs) play a crucial role in substituting the diets and household income of local people. Production of ALVs is, however, hampered by plant-parasitic nematodes, particularly Meloidogyne spp. The objectives of this study were: i) to determine the host suitability of 13 Amaranthus genotypes to Meloidogyne incognita and M. javanica in separate greenhouse experiments, and at three on-farm field sites, and ii) to verify resistance exhibited by genotype Thohoyandou, identified in greenhouse screenings, to the two said root-knot nematode species in micro plot studies. Glasshouse screenings for M. incognita showed reproduction factor (Rf) values