Assessment of genetic diversity of sorghum [sorghum bicolor (l.) Moench] germplasm in East and Central Africa

The study of genetic diversity in crops has a strong impact on plant breeding and maintenance of genetic resources. Comprehensive knowledge of the genetic biodiversity of cultivated and wild sorghum germplasm is an important prerequisite for sustainability of sorghum production. Recurrent droughts resulting from climate change scenarios’ in many East and Central Africa countries, where sorghum is a significant arable crop, can potentially lead to genetic erosion and loss of valuable genetic resources. This study aimed at assessing the extent and pattern of genetic diversity and population genetic structure among sorghum accessions from selected countries in East and Central Africa (Sudan, Kenya, Uganda, Ethiopia, Eritrea, Rwanda and Burundi) using39 microsatellites markers. The studied loci were polymorphic and revealed a total of 941 alleles in 1108 sorghum genotypes. High levels of diversity were revealed with Sudan (68.5) having the highest level of genetic diversity followed by Ethiopia (65.3), whereas Burundi (0.45) and Rwanda (0.33) had the lowest level of genetic diversity. Analysis of molecular variance indicated, all variance components to be highly significant (p<0.001). The bulk of the variation was partitioned within countries (68.1%) compared to among countries (31.9%). Genetic differentiation between countries based on FST values was high and highly significant (FST=0.32). Neighbour-joining (NJ) analysis formed two distinct clusters according to geographic regions, namely the central region (Kenya, Burundi, Uganda and Rwanda) and the eastern region (Sudan, Ethiopia, and Eritrea). Population structure analysis revealed six distinct populations corresponding to NJ analysis and geographical origin of accessions. Countries clustered independently with small integration, which indicated the role of farmers’ practices in the maintenance of landrace identity and genetic diversity. The observed high level of genetic diversity indicated that germplasm from East Africa should be preserved from genetic erosion, especially in countries with the highest diversity

Sustainability of the chemical manufacturing industry - Towards a new paradigm?

This paper describes the current situation of the chemicalmanufacturingindustry, with special reference to Europe and looks to the future sustainability demands on the sector, and the implications of these demands for chemical engineering education. These implications include definitions of sustainability criteria for the sector and the need for transparent reporting under the Triple Bottom Line approach. The response of the education system to the sustainability agenda over the years and a number of strategies to incorporate it into courses are described. The important role of chemical (or more generally, process) engineers in delivering sustainable solutions is emphasised but this also suggests that anew way of thinking about the discipline is required. Indeed, this paper argues that the demand for a sustainable chemicalmanufacturing sector could bring about the next paradigm shift in the discipline which has been predicted for some time

A community approach for pathogens and their arthropod vectors (ticks and fleas) in cats of sub-Saharan Africa

Background Arthropod-borne pathogens and their vectors are present throughout Africa. They have been well studied in livestock of sub-Saharan Africa, but poorly studied in companion animals. Given their socioeconomic importance, the African Small Companion Animal Network (AFSCAN), as part of the WSAVA Foundation, initiated a standardized multi-country surveillance study. Methods In six countries (Ghana, Kenya, Nigeria, Tanzania, Uganda, and Namibia) in both rural and urban settings, 160 infested cats were sampled to assess their ectoparasite community (ticks and fleas), as well as the micro-parasite prevalence within those ectoparasites (60 and 118 pools of ticks and fleas, respectively) and blood (276 cats, including 116 non-infested). Results Almost two thirds of all infested cats originated from Tanzania and Kenya. Despite the large macro-geographical variation, no consistent difference was found in ectoparasite diversity and numbers between East and West Africa. Far more flea-infested than tick-infested cats were found. The most dominant ectoparasite was Ctenocephalides felis. Among the ticks, the exophilic Haemaphysalis spp. were the commonest, including species that are not typically linked with companion animals (Haemaphysalis spinulosa and Haemaphysalis elliptica). The most prevalent pathogens found in the blood and fleas were Bartonella henselae and Mycoplasma haemofelis. In the ticks, the dog-associated Hepatozoon canis was most commonly found. A high degree of co-parasitism was found in all countries and habitats. Conclusions Our continent-wide standardized field study highlights the cat’s potential to serve as a reservoir of pathogens that can be transmitted to humans or livestock, especially when cats are expected to become more commonly kept in African villages and towns

A community approach of pathogens and their arthropod vectors (ticks and fleas) in dogs of African Sub-Sahara

BACKGROUND : Arthropod-borne pathogens and their vectors are present throughout Africa. They have been wellstudied 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.Additional file 1: Fig. S1. Overview of sampling times and average seasonal variation in precipitation and temperature. Table S1. Distribution of PCR signals allocated to an ectoparasite taxon (identification at genus level and more precise) in the infested dogs of urban and rural areas. Table S2. Distribution of co-infested dogs within the subpopulation of tick-infested dogs. Table S3. Co-infestations by different flea species (identification at genus level and lower). Table S4. Co-infections in dog blood. Table S5. Co-infections in dog ticks. Table S6. Co-infections in dog fleas. Table S7. Correlations with sero-prevalences. Table S8. Correlations with flea-borne pathogens.Additional file 2. Capture form.The Marie Sklodowska-Curie Actions, Bayer Animal Health GmbH, an Elanco Animal Health company, within the framework of the African Small Companion Animal Network (AFSCAN) program of the World Small Animal Veterinary Association (WASAVA) and supported by Idexx Laboratories and Clinvet International (Pty) Ltd.http://www.parasitesandvectors.comam2022Veterinary Tropical Disease

Die klassifikasie van 'n sianoprokarioot deur van ligmikroskopie, transmissie elektronmikroskopie en molekul?re tegnieke gebruik te maak

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