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Pseudobarbus quathlambae (Barnard, 1938) is a cyprinid minnow with a disjunct distribution divided into tributaries of the Upper Orange River system in the Lesotho Highlands and the Mzimkhulu River system in KwaZulu Natal Province (KZN), South Africa. Recent records in the Mzimkhulu River system extended the species' geographic range, and this could represent the last remnant population of this species in South Africa. However, its future existence is in doubt, because of continued threats to all the remnant populations by non-native fishes, and more recently by the building of large, interconnected dams as part of the Lesotho Highlands Water Project (LHWP). One of these dams has directly affected the Mohale population in central Lesotho, which was the largest of the seven extant populations. Analysis of mitochondrial control region sequences (534 bp) revealed considerable genetic differentiation (2.3–6.4%) and geographic structuring amongst the remnant populations. The phylogenetic analysis identified three lineages within P. quathlambae: (i) one in KZN, (ii) a second one in eastern Lesotho and (iii) a third one in Mohale, central Lesotho. The deep genetic divergence and pronounced geographic structuring amongst the populations suggests a long period of isolation, indicating they represent unique evolutionary units. [ABSTRACT FROM AUTHOR]

Extinction risk for 101 valid species and 18 unique genetic lineages of native freshwater fishes of South Africa was assessed in 2016 following the IUCN Red List criteria. An additional five species (three new species that were described and two species that were revalidated subsequent to the 2016 assessments) were assessed in the present study. A synthesis of the outcome of the assessments of the 106 valid species and 18 genetic lineages indicates that 45 (36%) of South Africa's freshwater fish taxa are threatened (7 Critically Endangered, 25 Endangered, 13 Vulnerable). Of the remaining taxa, 17 (14%) are listed as Near Threatened, 57 (46%) are Least Concern and five (4%) are Data Deficient. More than 60% of the endemic taxa are threatened. The Cape Fold Ecoregion has the highest proportion of threatened taxa (67%) due to the existence of a unique assemblage of narrow‐range endemic species. Galaxias and Pseudobarbus have the highest number of highly threatened taxa as most of the species and lineages in these genera are classified as either CR or EN. Major threats to the native freshwater fishes of the country are invasive fish species, deterioration of water quality, impoundments and excessive water abstraction, land use changes and modification of riverine habitats. Immediate conservation efforts should focus on securing remnant populations of highly threatened taxa and preventing deterioration in threat status, because recovery is rare. Accurate delimitation of species boundaries, mapping their distribution ranges, improved knowledge of pressures and long‐term monitoring of population trends need to be prioritised to generate credible data for the 2026 IUCN threat status assessments and designation of important fish areas as part of the National Freshwater Ecosystem Priority Areas (NFEPA) initiative. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Unconsolidated mud clast breccia facies in the hominin‐bearing (Homo naledi) Rising Star Cave, Cradle of Humankind, South Africa, are interpreted to have formed through a process termed sedimentary autobrecciation in this study. This process, by which most of the angular mud clast breccia deposits are thought to have formed autochthonously to para‐autochthonously via a combination of erosion, desiccation, diagenesis and microbial alteration of laminated mud deposits, is thought to have taken place under relatively dry (i.e. non‐flooded) conditions inside the cave. Subsequently, gravitational slumping and collapse was the dominant mechanism that produced the mud clast breccia deposits, which commonly accumulate into debris aprons. The mud clast breccia is typically associated with (micro) mammal fossils and is a common facies throughout the cave system, occurring in lithified and unlithified form. This facies has not been described from other cave localities in the Cradle of Humankind. Additionally, sedimentary autobrecciation took place during the deposition of some of the fossils within the Rising Star Cave, including the abundant Homo naledi skeletal remains found in the Dinaledi Subsystem. Reworking of the mud clast breccia deposits occurs in some chambers as they slump towards floor drains, resulting in the repositioning of fossils embedded in the breccias as evidenced by cross‐cutting manganese staining lines on some Homo naledi fossil remains. The formation of the unlithified mud clast breccia deposits is a slow process, with first order formation rates estimated to be ca 8 × 10−4 mm year−1. The slow formation of the unlithified mud clast breccia facies sediments and lack of laminated mud facies within these deposits, indicates that conditions in the Dinaledi Chamber were probably stable and dry for at least the last ca 300 ka, meaning that this study excludes Homo naledi being actively transported by fluvial mechanisms during the time their remains entered the cave. [ABSTRACT FROM AUTHOR]

An hourly infection model was used for a risk assessment of citrus black spot (CBS) caused by Phyllosticta citricarpa . The infection model contained a temperature-moisture response function and also included functions to simulate ascospore release and dispersal of pycnidiospores. A validation data set of 18 locations from South Africa and Australia was developed based on locations with known citrus black spot prevalence. An additional 67 sites from Europe and the United States with unknown prevalence were also identified. The model was run for each location with 9 years of hourly weather data from the National Centers for Environmental Prediction (NCEP) Climate Forecast System Reanalysis (CFSR) database. The infection scores for the sites with known prevalence where ranked and a threshold for suitability in a given year was derived from the average score of the lowest ranked moderate prevalence site. The results of the simulation confirm that locations in Florida were high risk while most locations in California and Europe were not at risk. The European location with the highest risk score was Andravida, Greece which had 67% of years suitable for ascosporic infection but only 11% of years were suitable for pycnidiosporic infection. There were six other sites in Europe that had frequency of years suitable for ascosporic infection greater than 22% including Pontecagnano, Italy; Kekrya, Greece; Reggio Calabria, Italy; Cozzo Spadaro, Italy; Messina, Italy; and Siracusa, Italy. Of these six sites only Reggio Calabria had a frequency of years suitable for pycnidiosporic infection greater than 0%. These six sites are predicted to have prevalence similar or less than Messina, South Africa, i.e. low and occasional. Other sites in Europe would best be described as likely to have no prevalence based on very low simulated scores for both spore types. Although Andravida had a similar risk of infection to moderate locations in South Africa there was a difference in the seasonality of infection periods. The ascosporic infection period score was similar between the two sites, but Andravida had a much lower pycnidiosporic infection score in the middle of the period of fruit susceptibility than Addo, South Africa. In Europe favorable climatic conditions are discontinuous, i.e., there is a low frequency of suitable seasons. This raises doubts about the ability of the pathogen to persist at a location and cause disease loss when favorable seasons reoccur. These results suggest that Europe is less suitable for CBS than suggested by an earlier study produced by the European Food Safety Authority using a similar model. The findings from our model simulations suggest that only a few isolated locations in the extreme south of Europe are likely to have a low to marginal risk of P. citricarpa establishment. [ABSTRACT FROM AUTHOR]

Here we present the results of a taphonomic study of the faunal assemblage associated with the hominin fossils (Australopithecus sediba) from the Malapa site. Results include estimation of body part representation, mortality profiles, type of fragmentation, identification of breakage patterns, and microscopic analysis of bone surfaces. The diversity of the faunal spectrum, presence of animals with climbing proclivities, abundance of complete and/or articulated specimens, occurrence of antimeric sets of elements, and lack of carnivore-modified bones, indicate that animals accumulated via a natural death trap leading to an area of the cave system with no access to mammalian scavengers. The co-occurrence of well preserved fossils, carnivore coprolites, deciduous teeth of brown hyaena, and some highly fragmented and poorly preserved remains supports the hypothesis of a mixing of sediments coming from distinct chambers, which collected at the bottom of the cave system through the action of periodic water flow. This combination of taphonomic features explains the remarkable state of preservation of the hominin fossils as well as some of the associated faunal material. [ABSTRACT FROM AUTHOR]

van Zyl, J.G., Sieverding, E.G., Viljoen, D.J., Fourie, P.H., 2014. Evaluation of two organosilicone adjuvants at reduced foliar spray volumes in South African citrus orchards of different canopy densities Crop Protection 00:0000-0000. Citrus producers in South Africa generally use high spray volumes (6000 to 16,000 l ha−1) to control pests and diseases adequately for the fresh fruit market. In order to study the benefit of organosilicone adjuvants at reduced spray volumes, trials were conducted with two organo tri-siloxane adjuvants. Two separate spray trials were conducted in the Western and Eastern Cape provinces of South Africa in uniform navel orange orchards. Break-Thru S240 (super-spreader) and Break-Thru Union (spreader-sticker), at recommended dosages per hectare (300 ml ha−1, respectively), were sprayed separately in combination with a yellow fluorescent pigment (1 ml l−1) at a high (20 l tree−1 ≈ 9600 to 12,100 l ha−1, depending on tree and inter-row spacing), medium (14 l tree−1 ≈ 6500 to 8500 l ha−1) and low (8 l tree−1 ≈ 3700 to 4800 l ha−1) spray application volumes. Sprays consisting of the fluorescent pigment in water alone were used as control treatments. Trees were sprayed from both sides with a commercial multi-fan tower sprayer (BSF-Multiwing) at a constant tractor speed (2.4 km h−1) and spray pressure (1500 kPa). The different spray volumes were achieved by using different spray nozzles (TeeJet Disc-Core type; full and hollow cone nozzles D3-DC56/46, D4-DC56/46, D5-DC56/46). Leaves were sampled from six canopy positions (inner and outer canopy position at bottom, middle and top of the tree). Deposition quantity and quality of fluorescent pigment were determined on upper and lower leaf surfaces using fluorometry, digital photomacrography and image analyses. Spray uniformity and efficiency were also compared among treatments. Deposition quantity generally increased with increasing spray volume, but normalised values showed better spray efficiency at lower volumes. In pruned and less dense canopies, a beneficial effect of adjuvants was observed in terms of deposition quantity, efficiency and uniformity, especially at reduced volume applications (14 l tree−1) on the inside and outside of the canopy. Little improvement in deposition quality was generally observed with the use of adjuvants. These benefits were not as evident in very dense canopies, illustrating the importance of canopy management when spraying at reduced volumes. Data obtained from the study is valuable for future improvement in spray application methodology in South Africa and other developing countries. [ABSTRACT FROM AUTHOR]

Pseudobarbus verloreni, a new species, is described from material collected in the Verlorenvlei River system on the west coast of South Africa. It differs from its congeners (except P. skeltoni, P. burchelli, and P. burgi) by the presence of two pairs of oral barbels. Pseudobarbus verloreni sp. n. can be distinguished from the three currently described double barbeled Pseudobarbus species by the following combination of characters: pigment pattern, generally deeper body relative to standard length, a longer intestine associated with the deeper body form, shorter snout relative to head length, and much shorter anterior barbels relative to head length. The new species is distinguished from P. burgi in the neighbouring Berg River system by its longer head and longer pre-dorsal length. It seems as if Pseudobarbus verloreni sp. n. has been extirpated from the Langvlei River system and face several threats to its survival in the Verlorenvlei River system. [ABSTRACT FROM AUTHOR]

A survey was undertaken on apple and pear trees in the main pome fruit growing areas of the Western Cape of South Africa to determine the aetiology of trunk diseases with specific reference to pathogens known to occur on grapevine, which are frequently cultivated in close proximity to these orchards. Several fungal genera containing known trunk disease pathogens were found. Two Diplodia species, D. seriata and Diplodia sp., were isolated along with Neofusicoccum australe and N. vitifusiforme. Four Phaeoacremonium species, Phaeoacremonium aleophilum, Pm. iranianum, Pm. mortoniae and Pm. viticola, two Phomopsis species linked to clades identified in former studies as Phomopsis theicola and Phomopsis sp. 7, and Eutypa lata were found. In addition, Paraconiothyrium brasiliense, Pr. variabile and a Pyrenochaetalike species were also isolated. Diplodia seriata (56% of total isolates) and Pm. aleophilum (22%) were most frequently isolated. First reports from pear wood include the Phaeoacremonium spp. and Paraconiothyrium brasiliense, while new reports from apple include Pm. aleophilum, Ph. theicola, Phomopsis sp. 7, Pr. variabile and E. lata. A pathogenicity trial was undertaken to determine the role of these species on apple, pear and grapevine shoots. Neofusicoccum australe caused the longest lesions on grapevine shoots, while Pr. variabile, D. seriata, Pm. mortoniae and the Pyrenochaeta-like sp. caused lesions that were longer than non-inoculated and non-pathogen experimental controls. On pear shoots, Diplodia sp. and N. australe caused the longest lesions, followed by D. seriata and E. lata. On apple shoots, the longest lesions were caused by N. australe and Pm. iranianum. These results demonstrate that apple and pear trees in Western Cape orchards are hosts to many known trunk pathogens along with potential new trunk disease-causing fungi. [ABSTRACT FROM AUTHOR]

Eutypa lata and Phaeomoniella chlamydospora, as well as several species in Botryosphaeriaceae, Phomopsis and Phaeoacremonium are known trunk pathogens of grapevines, which use pruning wounds as infection portals. Duration of pruning wound susceptibility to some of these pathogens was largely unknown. To address this question, plants of the cv. Chenin Blanc in a vineyard in the Stellenbosch area of South Africa were pruned at two stages, and then spray-inoculated with spore suspensions of E. lata, Pa. chlamydospora, Neofusicoccum australe and Phomopsis viticola directly after pruning, and 1, 2, 3, 7, 10, 14, 17 and 21 days after pruning. Eight months after inoculation, pathogen incidence in the treated wounds was determined by means of isolation from the pith and xylem tissue of treated plants. Lesions observed in these tissues were also measured and recorded. Results indicated that, irrespective of pathogen inoculated, pathogen incidence in the inoculated pruning wounds of both mid- and late winter declined with increasing wound age. The rate of decline was much slower in 2004 compared to 2005; however, wounds remained susceptible for 3 or more weeks after pruning in both years. Late winter wounds were more susceptible to infection than wounds made earlier in the season, while xylem tissue of pruning wounds generally proved more susceptible to all pathogens compared to exposed pith tissue. [ABSTRACT FROM AUTHOR]

Grapevine trunk diseases, caused by a range of phytopathogenic fungi, represent a serious impediment to wine and table grape production wherever these crops are cultivated. Previous studies have shown that the distribution of these pathogens is influenced by climate and that they are associated with a variety of internal wood decay symptoms. Little was known, however, about the influence of climate on the disease symptomatology of the different pathogens in a specific area. To address this, a survey was conducted in 30 wine and table grape vineyards in summer, marginal and winter rainfall regions of South Africa. Apart from Eutypa lata, which occurred only in the winter rainfall region, Phaeomoniella chlamydospora, species of Phaeoacremonium, Botryosphaeriaceae and Phomopsis occurred in all regions surveyed. The incidence of the fungal genera and species associated with trunk disease varied between regions, with overlapping symptom profiles that differed based on the climatic region. These findings suggest that symptom-based disease diagnosis alone is unreliable and that distribution and symptomatology of grapevine trunk pathogens are strongly influenced by climatic conditions in a specific production region. [ABSTRACT FROM AUTHOR]

This study investigated the challenges facing higher education institutions in South Africa in retaining and recruiting talent, especially in the discipline of indigenous African languages. A survey was conducted among a number of academics of nine universities in South Africa. Of the potential respondents of 50, 34 or 68% returned the questionnaires. The study first investigated the post-levels of respondents before measuring their age and the length of service. The effects of the generation gap as revealed by the responses, formed the independent variable. A clear indication of the generation gap could be observed with regard to two specific factors: post-levels and length of service. The post-levels of the total number of respondents support the claim that universities neglect young talent. The generation gap shows that African language departments are steered by aging staff members. The long service periods of current staff members indicate that human resource managers at universities have put a stop to staffing their African language departments. Some strategies could be adopted by higher education institutions in addressing the shortage of talent in indigenous African language disciplines. [ABSTRACT FROM AUTHOR]

We describe the geological, geochronological, geomorphological, and faunal context of the Malapa site and the fossils of Australopithecus sediba. The hominins occur with a macrofauna assemblage that existed in Africa between 2.36 and 1.50 million years ago (Ma). The fossils are encased in water-laid, clastic sediments that were deposited along the lower parts of what is now a deeply eroded cave system, immediately above a flowstone layer with a U-Pb date of 2.026 ± 0.021 Ma. The flowstone has a reversed paleomagnetic signature and the overlying hominin-bearing sediments are of normal polarity, indicating deposition during the 1.95- to 1.78-Ma Olduvai Subchron. The two hominin specimens were buried together in a single debris flow that lithified soon after deposition in a phreatic environment inaccessible to scavengers. [ABSTRACT FROM AUTHOR]

Abstract: Relationships among the historically isolated lineages of Pseudobarbus were reconstructed using molecular and morphological data. Contradictions between the molecular and morphological phylogenies suggest convergent evolution and homoplasy in some morphological characters. The earliest divergence in Pseudobarbus was between P. quathlambae in Lesotho and the rest of the genus associated with the Cape Foristic Region in South Africa. A close relationship between P. phlegethon from the Olifants River system on the west coast of South Africa and a lineage of P. afer from small river systems in Afrotemperate Forests on the south coast, can only be explained through previous occurrence and subsequent extinction of ancestral populations in the Gourits River system. Several river systems had confluences before reaching lower sea levels, most notably during the last glacial maximum about 18,000 years ago, explaining closely related populations across different river systems. Mainly river capture explains shared lineages across river systems that did not share a common confluence during lower sea levels. [Copyright &y& Elsevier]

Species-area relations (SARs) are among the few recognized general patterns of ecology, are empirical relations giving the number of species found within an area of a given size and were initially formulated for island environments. The use of SARs has been extended to mainland environments, and to give baseline estimates of extinction rates attending habitat loss. Using current species distributions based on atlas data, we examined the spatial variation of rates of species accumulation and species-area curves for Proteaceae species for all one-minute by one-minute areas within the Cape Floristic Region, South Africa. We compared SARs for current distributions to those generated from modeled future Protea distributions following climate change. Within one biome and for two different scales, there exists a very large spatial variation in turnover rates for current Proteaceae distributions, and we show that these rates will not remain constant as climate warming progresses. As climate changes in coming years, some areas will gain species due to migration, as other areas lose species, and still other areas maintain current rates of species accumulation/turnover. Both current and future distributions show highly variable rates of species accumulation across the landscape. This means that an average species-area relationship will hide a very large interval of variation among SARs, for both current and future Proteaceae distributions. The use of species-area relations to estimate species extinctions following loss of current habitat, or loss of future climatically-suitable area is likely to result in erroneous predictions. [ABSTRACT FROM AUTHOR]

Aim The phylogeography of the two closely related species Pseudobarbus afer and Pseudobarbus phlegethon was investigated to assess the association of evolutionary processes, inferred from mitochondrial DNA (mtDNA) sequence variation, with hypothetical palaeoriver systems and other climatic and landscape changes. Location One western and several southern river systems in South Africa. Methods We sampled known populations and confirmed known distribution gaps. This was followed by an assessment of mtDNA control region sequence variation for 31 localities across 17 river systems across the range of the species complex. A map of possible offshore drainage patterns during the last major regression event was constructed based on bathymetry and geological studies. Results The genetic distinction of four major lineages of P. afer strongly correspond with proposed palaeoriver systems. However, a western ‘Forest’ lineage, is widespread across two such proposed systems and is closely related to P. phlegethon on the west coast of South Africa. Both the ‘Krom’ and ‘St Francis’ lineages were identified in the single palaeoriver system proposed for St Francis Bay. A fourth ‘Mandela’ lineage is restricted to the one or two palaeoriver systems proposed for Nelson Mandela Bay. Four minor lineages were identified within the Forest lineage and two within the Mandela lineage. Main conclusions The close relationship between P. phlegethon and the Forest lineage of P. afer can only be explained by a series of river captures. We suggest the Gourits River system as a historical link that could account for this relationship. On the south coast, lower sea levels than at present allowed confluence between currently isolated river systems, offering opportunities for dispersal among these populations. At present, isolation between different river systems rather than dispersal appears to have a dominant influence on mtDNA diversity. [ABSTRACT FROM AUTHOR]

Plasmopara viticola populations in South Africa were studied for two consecutive grape growing seasons, in an organically managed and a conventional fungicide-sprayed vineyard. Three to four samplings in each season were genotyped with four microsatellite markers (GOB, CES, ISA and BER). Population differentiation ( Fst) between the conventional fungicide-sprayed vineyard and organically managed vineyard was low (0.004 and 0.016) in both growing seasons, suggesting one metapopulation. However, differences in the relative contribution of the predominant and new genotypes to epidemics in the two vineyards suggested that fungicide applications may have selected for reduced pathogen diversity. In both years and vineyards, sexual (oosporic) reproduction and/or migration occurred throughout the year and contributed between 12 and 74% to the epidemic. Hardy–Weinberg analyses suggest that South African P. viticola populations are randomly mating. Epidemics in both years and vineyards were dominated by one or two genotypes that each contributed between 14 and 67% to the epidemic through asexual reproduction. The remaining genotypes showed low levels of asexual reproduction, with most genotypes never being able to reproduce asexually. However, for some genotypes asexual reproduction was important, as it enabled survival of the genotypes from one season to the next. In total, ten genotypes were able to survive asexually or vegetatively from one season to the next. The populations were further characterized by the presence of a high frequency of isolates that most likely have elevated ploidy levels. [ABSTRACT FROM AUTHOR]

Botryosphaeriaceae are common dieback and canker pathogens of woody host plants, including stone fruit trees. In the present study the diversity of members of the Botryosphaeriaceae isolated from symptomatic wood of Prunus species (plum, peach, nectarine and apricot) was determined in stone fruit-growing areas in South Africa. Morphological and cultural characteristics as well as DNA sequence data (5.8S rDNA, ITS-1, ITS-2 and EF-1α) were used to identify known members and describe novel members of Botryosphaeriaceae. From the total number of wood samples collected (258) 67 isolates of Botryosphaeriaceae were obtained, from which eight species were identified. MI species were associated with wood necrosis. Diplodia seriata (= "Botryosphaeria" obtusa) was dominant, and present on all four Prunus species sampled, followed by Neofusicoccum vitifusiforme and N. australe. First reports from Prunus spp. include N. vitifusiforme, Dothiorella viticola and Diplodia pinea. This is also the first report of D. mutila from South Africa. Two species are newly described, namely Lasiodiplodia plurivora sp. nov. from P. salicina and Diplodia africana sp. nov. from P. persica. All species, except Dothiorella viticola, caused lesions on green nectarine and/or plum shoots in a detached shoot pathogenicity assay. [ABSTRACT FROM AUTHOR]

Petri disease is a vascular disease associated with decline and dieback of young grapevines. A major means of spread of the causal organisms, Phaeomoniella chlamydospora and Phaeoacremonium spp., is via infected propagation material. Since no curative control measures are known, proactive measures must be taken in grapevine nurseries to manage this disease. To study this aspect, semicommercial trials with naturally infected rootstock material were performed in grapevine nurseries in South Africa. Prior to grafting, rootstocks were treated as follows: l-h drench in suspensions of benomyl, phosphoric acid, different bacterial and Trichoderma formulations, water, or hot water treated (HWT; 30 min at 50°C). Grafted cuttings were planted and grown in a greenhouse and two commercial field nurseries and uprooted 8 months later. In instances where rootstocks were treated with benomyl or Trichoderma formulations, the incidences of Phaeomoniella and Phaeoacremonium in grafted cuttings and uprooted nursery vines were significantly lower than that of the water treatment. However, the reduction was most consistent and noteworthy in vines on rootstocks that received HWT prior to grafting. HWT of dormant nursery vines effected a similar reduction in Phaeomoniella and Phaeoacremonium incidence. Root-stock drenches in benomyl and/or Trichoderma formulations could thus be integrated with HWT for the proactive management of Petri disease in grapevine nurseries. [ABSTRACT FROM AUTHOR]

This article focusses on the religious encounter between Portuguese missionaries and the African societies in Southern Africa. It is argued that the crusading mentality embedded in mediaeval Catholicism and the terms of the Padruado underpinned and reinforced the views and attitudes that Portuguese missionaries constructed around African religion and ritual. The perceptions that Christianity was superior to, and in no position to negotiate and dialogue with African religion, contributed significantly towards their failure to understand and to evangelise the societies they came in contact with. Moreover the failure to appreciate that traditional religion was a centrifugal force around which all life, not just kingship, gravitated, resulted in their disillusionment and immature abandonment of the mission field. This analysis is based on, and aided by, secondary sources written on the Portuguese activities in Southern Africa. [ABSTRACT FROM AUTHOR]

Focuses on the reproductive and feeding biology of the Natal mountain catfish, Amphilius natalensis in South Africa. Gametogenesis pattern of catfish; Conclusion drawn on the basis of stomach content analysis and observations on feeding morphology; Preys that were eaten by catfishes.

Newly exposed cave sediments at the Malapa site include a flowstone layer capping the sedimentary unit containing the Australopithecus sediba fossils. Uranium-lead dating of the flowstone, combined with paleomagnetic and stratigraphic analysis of the flowstone and underlying sediments, provides a tightly constrained date of 1.977 ± 0.002 million years ago (Ma) for these fossils. This refined dating suggests that Au. sediba from Malapa predates the earliest uncontested evidence for Homo in Africa. [ABSTRACT FROM AUTHOR]

Citrus black spot (CBS), caused by Phyllosticta citricarpa, is a disease that affects citrus worldwide. In different regions of the world where both mating types occur, reports differ as to whether asexually produced pycnidiospores play an important role in the epidemiology of CBS and fruit infections. Therefore, we investigated the potential role of pycnidiospores in two lemon orchards in South Africa by using microsatellite-based analysis of fruit populations over time (two seasons) and space (distance). The two orchards were situated in the semiarid North West province (NW) and subtropical Mpumalanga province (MP). Each population contained both mating types in 1:1 ratios, and linkage disequilibrium analysis indicated a random mating population. A total of 109 and 94 multilocus genotypes (MLGs) were detected across the two seasons in the NW and MP orchards, respectively. Psex analyses indicated that most MLGs probably resulted from sexual reproduction, but there were six predominant MLGs in each orchard that were probably replicated via asexual reproduction. Each of the predominant MLGs was monomorphic for mating type. In the NW, five predominant and widespread MLGs caused 46 and 44% of the fruit infections in the two seasons, whereas in MP, three MLGs caused 34 and 48% of the infections. Asexual reproduction in both orchards was supported by low MLG evenness values in all populations. In both orchards, distance was not a reliable predictor of population genetic substructuring or season. Populations of P. citricarpa in the MP and NW orchards were significantly genetically differentiated from each other. [ABSTRACT FROM AUTHOR]

• Three pulses of Palaeoproterozoic magmatism in the Namaqua Sector. • Model ages reflect melting of pre-existing arc-related rocks to produce I-type granites. • Orthogneisses of the Gladkop Suite are confined to the Steinkopf Domain. • The Steinkopf Domain is bounded by the Groothoek and Skelmfontein thrusts. • The Gladkop Suite rocks show evidence of a Statherian magmatic-metamorphic event. The Steinkopf Domain covers about 3500 km2 of the NW corner of the Bushmanland Subprovince of the late Mesoproterozoic (ca. 1.2–1.0 Ga) Namaqua Sector, Namaqua-Natal Province. Granitoid orthogneisses of the Gladkop Suite constitute about 90% of the exposed surface area of the domain. The Gladkop Suite comprises three distinct magmatic phases. From intrusive relationships, the oldest, Steinkopf Gneiss, comprises grey migmatitic biotite granitic to granodioritic orthogneiss with minor diorite. It tends to show transitional contacts with the compositionally homogeneous, grey biotite granitic Brandewynsbank Gneiss, but both are intruded by the leucocratic, pinkish Noenoemaasberg Gneiss. A total of ten representative samples of the three phases give statistically identical Orosirian crystallisation ages between 1810 and 1825 Ma. 31 whole-rock major and trace element geochemical analyses show that the rocks form a sub-alkaline, high-K calc-alkaline, peraluminous to weakly metaluminous series, with broadly arc-like, I-type granite characteristics. Coherent geochemical trends suggest they are co-magmatic. Radiogenic isotope data show that the rocks were, however, not generated in a juvenile arc setting, but one with a significant component of older crustal material, including possible late Neoarchean crust and cannibalisation of older, 2.0–1.9 Ga, magmatic arc crust, such as the nearby Sperrgebiet Domain and Richtersveld Magmatic Arc, respectively. The suite thus represents a third pulse of arc-related Palaeoproterozoic igneous activity marginal to the magmatism of older arcs documented to the north. The zircon data show evidence for significant zircon growth at ca. 1.75 and 1.2–1.03 Ga testifying to later metamorphism. The former marks an elusive hitherto unrecognised Statherian-Calymmian magmatic-metamorphic event, with the latter representing the effects of the main Namaqua orogenesis which imposed the main regional tectonic fabrics upon the Steinkopf Domain and was associated with thermal pulses accompanying widespread polyphase granitoid magmatism. The rocks of the Gladkop Suite are migmatised and this might be attributable to either post-crystallisation metamorphic event. Our study has helped to constrain crustal evolution in NW Namaqualand and puts forward a model for the geotectonic setting for the Steinkopf Domain within the Bushmanland Subprovince, the bulk of which is characterised by a much more cryptic Palaeoproterozoic infrastructure. [ABSTRACT FROM AUTHOR]

Abstract: Green mould, caused by Penicillium digitatum, is responsible for major postharvest fruit losses on the South African fresh citrus export market. Some of these losses as well as fungicide resistance development can be attributed to sub-optimal imazalil (IMZ) residue loading on citrus fruit (<2μgg−1), which is commonly the case in South African packhouses. This will result in loss of control and sporulation inhibition on decayed fruit. IMZ formulation [IMZ sulphate and emulsifiable concentrate (EC)], solution pH (IMZ sulphate at 500μgmL−1 buffered with NaHCO3 or NaOH to pH 6 and 8) and exposure time (15–540s) were investigated in order to improve IMZ residue loading and the green mould control on Clementine mandarin, ‘Eureka’ lemon, and navel and Valencia orange fruit. Exposure time had no significant effect on residue loading in the unbuffered IMZ sulphate solution (pH 3). No differences were observed between the pH buffers used, but residue loading improved with increase in pH. The maximum residue limit (MRL) of 5.0μgg−1 was exceeded following dip treatment in the IMZ EC (after 75s exposure time), and IMZ sulphate at pH 8 using NaHCO3 (77s) or NaOH (89s) as buffer. The MRL was exceeded after 161s in IMZ sulphate solutions buffered at pH 6 with either NaHCO3 or NaOH. An IMZ residue-loading curve was prepared from which residue levels can be predicted for the control of IMZ-sensitive and IMZ-resistant isolates of P. digitatum. From this model the benchmark residue level for 95% control of an IMZ-sensitive isolate and of an IMZ-resistant isolate were predicted to be 0.81 and 2.64μgg−1, respectively. Residue loading can be improved by adjusting the pH level of an IMZ sulphate solution to 6 or by using the IMZ EC formulation, but exposure time should be restricted to 45s so as not to exceed the MRL. Conversely, sufficient exposure time of ≈90s in an unbuffered IMZ sulphate solution (pH 3) will result to improved green mould control, but with residue loading below 2μgg−1. The resistant isolate could not be controlled adequately with residue levels below the MRL, therewith indicating the practical relevance of IMZ resistance. [Copyright &y& Elsevier]

Abstract: Imazalil (IMZ) is commonly applied in South African citrus packhouses for the control of green mould, caused by Penicillium digitatum, yet the disease still causes significant postharvest losses. The maximum residue limit (MRL) for IMZ on citrus fruit is 5μgg−1, whereas 2–3μgg−1 is a biologically effective residue level that should at least inhibit green mould sporulation. Standard compliance auditing of residue levels of citrus fruit, however, indicate that fruit from the majority of packhouses have residues of ≈1μgg−1. Poor disease control from insufficient residue loading might further be compounded by the presence of IMZ-resistant isolates of P. digitatum in packhouses. This study was conducted to assess the current status of IMZ application in South African packhouses, to determine the adequate residue levels needed to control green mould and inhibit its sporulation using both IMZ sensitive and resistant isolates, to investigate IMZ application methods and resultant residue levels in commercial citrus packhouses, and to study optimisation of modes of IMZ application in citrus packhouses. Factors studied were IMZ concentration, application type (spray vs. dip and drench), exposure time, solution temperature and pH, as well as curative and protective control of P. digitatum. The packhouse survey showed that the majority of packhouses applied IMZ in a sulphate salt formulation through a fungicide dip tank, and loaded an IMZ residue of ≈1μgg−1. In dip applications, IMZ had excellent curative and protective activity against Penicillium isolates sensitive to IMZ. However, curative control of IMZ resistant isolates was substantially reduced and protective control was lost, even at twice the recommended concentration, nor was sporulation inhibited. The use of sodium bicarbonate (2%) buffered imazalil sulphate solutions at pH ±8, compared with pH ±3 of the unbuffered solutions, markedly increased IMZ residue loading on Navel and Valencia oranges and improved curative and protective control of IMZ resistant isolates. Exposure time did not affect IMZ residue loading in IMZ sulphate solutions at pH 3, although the MRL was exceeded after 45s exposure in pH 8 solutions. Imazalil applied through spray or drench application improved residue loading, but green mould control was less effective than after dip application. [Copyright &y& Elsevier]

Despite a rich African Plio-Pleistocene hominin fossil record, the ancestry of Homo and its relation to earlier australopithecines remain unresolved. Here we report on two partial skeletons with an age of 1.95 to 1.78 million years. The fossils were encased in cave deposits at the Malapa site in South Africa. The skeletons were found close together and are directly associated with craniodental remains. Together they represent a new species of Australopithecus that is probably descended from Australopithecus africanus. Combined craniodental and postcranial evidence demonstrates that this new species shares more derived features with early Homo than any other australopith species and thus might help reveal the ancestor of that genus. [ABSTRACT FROM AUTHOR]

Background: Rotavirus is the most common cause of severe gastroenteritis among young children worldwide. Data are needed to assess the efficacy of the rotavirus vaccine in African children. Methods: We conducted a randomized, placebo-controlled, multicenter trial in South Africa (3166 infants; 64.1% of the total) and Malawi (1773 infants; 35.9% of the total) to evaluate the efficacy of a live, oral rotavirus vaccine in preventing severe rotavirus gastroenteritis. Healthy infants were randomly assigned in a 1:1:1 ratio to receive two doses of vaccine (in addition to one dose of placebo) or three doses of vaccine — the pooled vaccine group — or three doses of placebo at 6, 10, and 14 weeks of age. Episodes of gastroenteritis caused by wild-type rotavirus during the first year of life were assessed through active follow-up surveillance and were graded with the use of the Vesikari scale. Results: A total of 4939 infants were enrolled and randomly assigned to one of the three groups; 1647 infants received two doses of the vaccine, 1651 infants received three doses of the vaccine, and 1641 received placebo. Of the 4417 infants included in the per-protocol efficacy analysis, severe rotavirus gastroenteritis occurred in 4.9% of the infants in the placebo group and in 1.9% of those in the pooled vaccine group (vaccine efficacy, 61.2%; 95% confidence interval, 44.0 to 73.2). Vaccine efficacy was lower in Malawi than in South Africa (49.4% vs. 76.9%); however, the number of episodes of severe rotavirus gastroenteritis that were prevented was greater in Malawi than in South Africa (6.7 vs. 4.2 cases prevented per 100 infants vaccinated per year). Efficacy against all-cause severe gastroenteritis was 30.2%. At least one serious adverse event was reported in 9.7% of the infants in the pooled vaccine group and in 11.5% of the infants in the placebo group. Conclusions: Human rotavirus vaccine significantly reduced the incidence of severe rotavirus gastroenteritis among African infants during the first year of life. (ClinicalTrials.gov number, NCT00241644.) N Engl J Med 2010;362:289-98. [ABSTRACT FROM AUTHOR]

Phyllosticta citricarpa is a fungal pathogen causing citrus black spot (CBS). As a regulated pest in some countries, the presence of the pathogen limits the export of fruit and is therefore of agricultural and economic importance. In this study, we used high throughput sequencing data to infer the global phylogeographic distribution of this pathogen, including 71 isolates from eight countries, Argentina, Australia, Brazil, China, Cuba, Eswatini, South Africa and the United States of America. We assembled draft genomes and used a pairwise read mapping approach for the detection and enumeration of variants between isolates. We performed SSR marker discovery based on the assembled genome with the best assembly statistics, and generated genotype profiles for all isolates with 1987 SSR markers in silico. Furthermore, we identified 32,560 SNPs relative to a reference sequence followed by population genetic analyses based on the three datasets; pairwise variant counts, SSR genotypes and SNP genotypes. All three analysis approaches gave similar overall results. Possible pathways of dissemination among the populations from China, Australia, southern Africa and the Americas are postulated. The Chinese population is the most diverse, and is genetically the furthest removed from all other populations, and is therefore considered the closest to the origin of the pathogen. Isolates from Australia, Eswatini and the South African province Mpumalanga are closely associated and clustered together with those from Argentina and Brazil. The Eastern Cape, North West, and KwaZulu-Natal populations in South Africa grouped in another cluster, while isolates from Limpopo are distributed between the two aforementioned clusters. Southern African populations showed a close relationship to populations in North America, and could be a possible source of P. citricarpa populations that are now found in North America. This study represents the largest whole genome sequencing survey of P. citricarpa to date and provides a more comprehensive assessment of the population genetic diversity and connectivity of P. citricarpa from different geographic origins. This information could further assist in a better understanding of the epidemiology of the CBS pathogen, its long-distance dispersal and dissemination pathways, and can be used to refine phytosanitary regulations and management programmes for the disease., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

The genus Pilidiella, including its teleomorphs in Schizoparme, has a cosmopolitan distribution and is associated with disease symptoms on many plants. In the past, conidial pigmentation has been used as a character to separate Pilidiella (hyaline to pale brown conidia) from Coniella (dark brown conidia). In recent years, however, the two genera have been regarded as synonymous, the older name Coniella having priority. To address the generic question, sequences of the internal transcribed spacer region (ITS1, ITS2), 5.8S gene, large subunit (LSU) and elongation factor 1-alpha gene (EF 1-alpha) were analysed to compare the type species of Pilidiella and Coniella. All three gene regions supported the separation of Coniella from Pilidiella, with the majority of taxa residing in Pilidiella. Pilidiella is characterised by having species with hyaline to pale brown conidia (avg. length:width > 1.5), in contrast to the dark brown conidia of Coniella (avg. length:width < or = 1.5). Pilidiella diplodiella, which is a pathogen associated with white rot of grapevines, was shown to be an older name for C. petrakii. To delineate species in the P. diplodiella species complex, isolates were also compared based on histone (H3) gene sequences. Analyses derived from these sequence data separated P. diplodiella from a newly described species, P. diplodiopsis. The new species P. eucalyptorum sp. nov. is proposed for isolates formerly treated as C. fragariae and associated with leaf spots of Eucalyptus spp. This species clustered basal to Pilidiella, and may represent yet a third genus within this complex. Pilidiella destruens sp. nov. is newly described as anamorph of Schizoparme destruens, which is associated with twig dieback of Eucalyptus spp. in Hawaii. A key based on morphological characteristics is provided to separate the taxa treated in this study.