Biological control of South African plants that are invasive elsewhere in the world: A review of earlier and current programmes
- Olckers, Terence, Coetzee, Julie A, Egli, Daniella, Martin, Grant D, Paterson, Iain D, Sutton, Guy F, Wood, Alan R
- Authors: Olckers, Terence , Coetzee, Julie A , Egli, Daniella , Martin, Grant D , Paterson, Iain D , Sutton, Guy F , Wood, Alan R
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/414336 , vital:71137 , xlink:href="https://hdl.handle.net/10520/ejc-ento_v29_n3_a21"
- Description: South Africa supports a rich floral diversity, with 21 643 native plant taxa that include a high proportion (76.3%) of endemic species, and many of these favoured as ornamentals, both locally and globally. Consequently, South Africa has contributed substantially to global plant invasions, with 1093 native taxa (5% of all species) naturalized in other countries. At least 80 taxa are invasive in natural or semi-natural ecosystems elsewhere, while an additional 132 taxa are potentially invasive. Of the global naturalized flora, 8.2% originate from South Africa and largely comprise species of Poaceae, Asteraceae, Iridaceae and Fabaceae. Australia, in particular, but also Europe and North America are major recipients of South African weeds. However, few countries have targeted South African plants for biological control (biocontrol), with most efforts undertaken by Australia. Previous and current targets have involved only 26 species with 17 agents (15 insects, one mite and one rust fungus) of South African origin released on five target species in Australia and the United States of America. South Africa’s history of weed biocontrol, together with a large cohort of active scientists, is currently facilitating several internationally funded programmes targeting invasive plants of South African origin. In particular, the recently inaugurated Centre for Biological Control at Rhodes University and the University of KwaZulu-Natal have provided the impetus for novel efforts on five new target species and renewed efforts on four previously targeted species. In this contribution, we review the history of earlier biocontrol programmes against weeds of South African origin and the status of projects currently in progress in South Africa.
- Full Text:
- Date Issued: 2021
- Authors: Olckers, Terence , Coetzee, Julie A , Egli, Daniella , Martin, Grant D , Paterson, Iain D , Sutton, Guy F , Wood, Alan R
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/414336 , vital:71137 , xlink:href="https://hdl.handle.net/10520/ejc-ento_v29_n3_a21"
- Description: South Africa supports a rich floral diversity, with 21 643 native plant taxa that include a high proportion (76.3%) of endemic species, and many of these favoured as ornamentals, both locally and globally. Consequently, South Africa has contributed substantially to global plant invasions, with 1093 native taxa (5% of all species) naturalized in other countries. At least 80 taxa are invasive in natural or semi-natural ecosystems elsewhere, while an additional 132 taxa are potentially invasive. Of the global naturalized flora, 8.2% originate from South Africa and largely comprise species of Poaceae, Asteraceae, Iridaceae and Fabaceae. Australia, in particular, but also Europe and North America are major recipients of South African weeds. However, few countries have targeted South African plants for biological control (biocontrol), with most efforts undertaken by Australia. Previous and current targets have involved only 26 species with 17 agents (15 insects, one mite and one rust fungus) of South African origin released on five target species in Australia and the United States of America. South Africa’s history of weed biocontrol, together with a large cohort of active scientists, is currently facilitating several internationally funded programmes targeting invasive plants of South African origin. In particular, the recently inaugurated Centre for Biological Control at Rhodes University and the University of KwaZulu-Natal have provided the impetus for novel efforts on five new target species and renewed efforts on four previously targeted species. In this contribution, we review the history of earlier biocontrol programmes against weeds of South African origin and the status of projects currently in progress in South Africa.
- Full Text:
- Date Issued: 2021
Rediscovery, taxonomic status, and phylogenetic relationships of two rare and endemic snakes (Serpentes: Psammophiinae) from the southwestern Angolan plateau
- Branch, William R, Baptista, Ninda L, Keates, Chad, Edwards, Shelley
- Authors: Branch, William R , Baptista, Ninda L , Keates, Chad , Edwards, Shelley
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/462658 , vital:76323 , xlink:href="https://zoobank.org/References/7FEE7CB2-9A74-407A-A9DB-DB714FEF1E0F"
- Description: Two rare and endemic psammophines (Serpentes: Psammophiinae) occur in Angola. The taxonomic status of Psammophylax rhombeatus ocellatus Bocage, 1873 and Psammophis ansorgii Boulenger, 1905 have long remained problematic, with both having varied past and present taxonomic assignments, and whose distributions may therefore present zoogeographic anomalies. Little was known of their biology, habitat associations, or phylogenetic relationships. New material was collected during biodiversity surveys of the Humpata Plateau, near Lubango, Angola. It allowed fuller descriptions of scalation and live coloration for both species, and resolution of their taxonomic status. Genetic analysis confirms that both are distinct at the specific level. In addition, within Psammophis, Jalla’s Sand Snake (Psammophis jallae Peracca, 1896), of which P. rohani Angel, 1925, remains a synonym, is sister to P. ansorgii, and Boulenger’s comment on similarities with P. crucifer are not supported. The status of an unusual skaapsteker from Calueque, Cunene Province, Angola, is discussed and its assignment to Ps. ocellatus is provisional and requires additional material for taxonomic resolution. The new P. ansorgii records from Tundavala represent a range (+ 400 km southwest) and altitude (1800 m to 2286 m asl) extension from the previous only known precise locality of Bela Vista (= Catchiungo), Huambo Province, whilst that for Ps. ocellatus doubles the known altitude from 1108 m to 2286 m asl and extends the range about 122 km to the northwest from historical material from the plateau of Huíla and Cunene provinces.
- Full Text:
- Date Issued: 2019
- Authors: Branch, William R , Baptista, Ninda L , Keates, Chad , Edwards, Shelley
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/462658 , vital:76323 , xlink:href="https://zoobank.org/References/7FEE7CB2-9A74-407A-A9DB-DB714FEF1E0F"
- Description: Two rare and endemic psammophines (Serpentes: Psammophiinae) occur in Angola. The taxonomic status of Psammophylax rhombeatus ocellatus Bocage, 1873 and Psammophis ansorgii Boulenger, 1905 have long remained problematic, with both having varied past and present taxonomic assignments, and whose distributions may therefore present zoogeographic anomalies. Little was known of their biology, habitat associations, or phylogenetic relationships. New material was collected during biodiversity surveys of the Humpata Plateau, near Lubango, Angola. It allowed fuller descriptions of scalation and live coloration for both species, and resolution of their taxonomic status. Genetic analysis confirms that both are distinct at the specific level. In addition, within Psammophis, Jalla’s Sand Snake (Psammophis jallae Peracca, 1896), of which P. rohani Angel, 1925, remains a synonym, is sister to P. ansorgii, and Boulenger’s comment on similarities with P. crucifer are not supported. The status of an unusual skaapsteker from Calueque, Cunene Province, Angola, is discussed and its assignment to Ps. ocellatus is provisional and requires additional material for taxonomic resolution. The new P. ansorgii records from Tundavala represent a range (+ 400 km southwest) and altitude (1800 m to 2286 m asl) extension from the previous only known precise locality of Bela Vista (= Catchiungo), Huambo Province, whilst that for Ps. ocellatus doubles the known altitude from 1108 m to 2286 m asl and extends the range about 122 km to the northwest from historical material from the plateau of Huíla and Cunene provinces.
- Full Text:
- Date Issued: 2019
Ursolic Acid and its derivatives as bioactive agents
- Mlala, Sithenkosi, Oyedeji, Adebola Omowunmi, Gondwe, Mavuto, Oyedeji, Opeoluwa Oyehan
- Authors: Mlala, Sithenkosi , Oyedeji, Adebola Omowunmi , Gondwe, Mavuto , Oyedeji, Opeoluwa Oyehan
- Date: 2019
- Subjects: Noncommunicable diseases , Pentacyclic triterpenoids , Ursolic acid , Clinical trials
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/1576 , vital:37793 , https://doi.org/10.3390/molecules24152751
- Description: Non-communicable diseases (NCDs) such as cancer, diabetes, and chronic respiratory and cardiovascular diseases continue to be threatening and deadly to human kind. Resistance to and side effects of known drugs for treatment further increase the threat, while at the same time leaving scientists to search for alternative sources from nature, especially from plants. Pentacyclic triterpenoids (PT) from medicinal plants have been identified as one class of secondary metabolites that could play a critical role in the treatment and management of several NCDs. One of such PT is ursolic acid (UA, 3 β-hydroxy-urs-12-en-28-oic acid), which possesses important biological effects, including anti-inflammatory, anticancer, antidiabetic, antioxidant and antibacterial effects, but its bioavailability and solubility limits its clinical application. Mimusops caffra, Ilex paraguarieni, and Glechoma hederacea, have been reported as major sources of UA. The chemistry of UA has been studied extensively based on the literature, with modifications mostly having been made at positions C-3 (hydroxyl), C12-C13 (double bonds) and C-28 (carboxylic acid), leading to several UA derivatives (esters, amides, oxadiazole quinolone, etc.) with enhanced potency, bioavailability and water solubility. This article comprehensively reviews the information that has become available over the last decade with respect to the sources, chemistry, biological potency and clinical trials of UA and its derivatives as potential therapeutic agents, with a focus on addressing NCD.
- Full Text:
- Date Issued: 2019
- Authors: Mlala, Sithenkosi , Oyedeji, Adebola Omowunmi , Gondwe, Mavuto , Oyedeji, Opeoluwa Oyehan
- Date: 2019
- Subjects: Noncommunicable diseases , Pentacyclic triterpenoids , Ursolic acid , Clinical trials
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/1576 , vital:37793 , https://doi.org/10.3390/molecules24152751
- Description: Non-communicable diseases (NCDs) such as cancer, diabetes, and chronic respiratory and cardiovascular diseases continue to be threatening and deadly to human kind. Resistance to and side effects of known drugs for treatment further increase the threat, while at the same time leaving scientists to search for alternative sources from nature, especially from plants. Pentacyclic triterpenoids (PT) from medicinal plants have been identified as one class of secondary metabolites that could play a critical role in the treatment and management of several NCDs. One of such PT is ursolic acid (UA, 3 β-hydroxy-urs-12-en-28-oic acid), which possesses important biological effects, including anti-inflammatory, anticancer, antidiabetic, antioxidant and antibacterial effects, but its bioavailability and solubility limits its clinical application. Mimusops caffra, Ilex paraguarieni, and Glechoma hederacea, have been reported as major sources of UA. The chemistry of UA has been studied extensively based on the literature, with modifications mostly having been made at positions C-3 (hydroxyl), C12-C13 (double bonds) and C-28 (carboxylic acid), leading to several UA derivatives (esters, amides, oxadiazole quinolone, etc.) with enhanced potency, bioavailability and water solubility. This article comprehensively reviews the information that has become available over the last decade with respect to the sources, chemistry, biological potency and clinical trials of UA and its derivatives as potential therapeutic agents, with a focus on addressing NCD.
- Full Text:
- Date Issued: 2019
Critical realist versus mainstream interdisciplinarity
- Authors: Price, Leigh
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/391143 , vital:68624 , xlink:href="https://doi.org/10.1179/1476743013Z.00000000019"
- Description: In this paper I argue for the superiority of a critical realist understanding of interdisciplinarity over a mainstream understanding of it. I begin by exploring the reasons for the failure of mainstream researchers to achieve interdisciplinarity. My main argument is that mainstream interdisciplinary researchers tend to hypostatize facts, fetishize constant conjunctions of events and apply to open systems an epistemology designed for closed systems. I also explain how mainstream interdisciplinarity supports oppression and gross inequality. I argue that mainstream interdisciplinarity is not true interdisciplinarity and refer to it accordingly as ‘condisciplinarity’. By way of example, I examine the condisciplinarity of the World Health Organization’s ecological model applied to the issue of men’s violence against women. Specifically, I argue that critical realist interdisciplinarity is preferable because it acknowledges inter alia the empirical, actual and real layers of reality, which allows it to develop depth-explanations of phenomena. In practice, this means that critical realist interdisciplinarity can potentially provide explanations that, compared to condisciplinarity, are broader (include more of the human and non-human context) and deeper (include for example individuals’ conscious and unconscious psychological motivations). In the World Health Organization’s example of the causes of men’s violence against women, condisciplinarity resulted in the absence of historical, global and unconscious aspects of the problem. It is also restricted the analysis to reductive, constant-conjunction based theories of the causes of the problem, specifically ‘risk factors’, thereby providing a relatively shallow explanation for the problem.
- Full Text:
- Date Issued: 2014
- Authors: Price, Leigh
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/391143 , vital:68624 , xlink:href="https://doi.org/10.1179/1476743013Z.00000000019"
- Description: In this paper I argue for the superiority of a critical realist understanding of interdisciplinarity over a mainstream understanding of it. I begin by exploring the reasons for the failure of mainstream researchers to achieve interdisciplinarity. My main argument is that mainstream interdisciplinary researchers tend to hypostatize facts, fetishize constant conjunctions of events and apply to open systems an epistemology designed for closed systems. I also explain how mainstream interdisciplinarity supports oppression and gross inequality. I argue that mainstream interdisciplinarity is not true interdisciplinarity and refer to it accordingly as ‘condisciplinarity’. By way of example, I examine the condisciplinarity of the World Health Organization’s ecological model applied to the issue of men’s violence against women. Specifically, I argue that critical realist interdisciplinarity is preferable because it acknowledges inter alia the empirical, actual and real layers of reality, which allows it to develop depth-explanations of phenomena. In practice, this means that critical realist interdisciplinarity can potentially provide explanations that, compared to condisciplinarity, are broader (include more of the human and non-human context) and deeper (include for example individuals’ conscious and unconscious psychological motivations). In the World Health Organization’s example of the causes of men’s violence against women, condisciplinarity resulted in the absence of historical, global and unconscious aspects of the problem. It is also restricted the analysis to reductive, constant-conjunction based theories of the causes of the problem, specifically ‘risk factors’, thereby providing a relatively shallow explanation for the problem.
- Full Text:
- Date Issued: 2014
'I won't be squeezed into someone else's frame': Stories of supervisor selection
- Harrison, Liz, McKenna, Sioux, Searle, Ruth
- Authors: Harrison, Liz , McKenna, Sioux , Searle, Ruth
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187395 , vital:44629 , xlink:href="https://hdl.handle.net/10520/EJC15100"
- Description: Using a collection of stories from a group of women who belong to a PhD support group, this article tracks the issue of choosing a supervisor. These women are all academics and therefore had some claim to an "insider" status but as novice researchers they were also "outsiders". Their discussions around how and why they chose their supervisors highlight issues often underplayed or ignored in textbooks on postgraduate supervision. In particular, this article examines issues of knowledge, embodied subjectivity and power by following three questions that arise from the data : whose knowing is important; who should I be, and whose PhD is it?
- Full Text:
- Date Issued: 2010
- Authors: Harrison, Liz , McKenna, Sioux , Searle, Ruth
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187395 , vital:44629 , xlink:href="https://hdl.handle.net/10520/EJC15100"
- Description: Using a collection of stories from a group of women who belong to a PhD support group, this article tracks the issue of choosing a supervisor. These women are all academics and therefore had some claim to an "insider" status but as novice researchers they were also "outsiders". Their discussions around how and why they chose their supervisors highlight issues often underplayed or ignored in textbooks on postgraduate supervision. In particular, this article examines issues of knowledge, embodied subjectivity and power by following three questions that arise from the data : whose knowing is important; who should I be, and whose PhD is it?
- Full Text:
- Date Issued: 2010
Philosophers and the Poor
- Authors: Jones, Ward E
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/275671 , vital:55068 , xlink:href="https://doi.org/10.3167/th.2010.5712506"
- Description: This is a programmatic paper, calling for the renewal andmodernisation of the therapeutic approach to philosophy found inEpicureans, Stoics, and Skeptics; and, in particular, for an applicationof the therapeutic approach to the life of poverty. The general assump-tion behind a therapeutic approach to philosophy is that it is possiblefor someone to be exposed to philosophical work which leads her toan improved understanding of herself and her situation, and for herlife to be improved by this understanding. After offering a sketch ofhow, given the current nature of academic philosophy, such work willbe carried out and disseminated, I suggest three areas in which philo-sophical discourse could have a therapeutic affect on the poor.
- Full Text:
- Date Issued: 2010
- Authors: Jones, Ward E
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/275671 , vital:55068 , xlink:href="https://doi.org/10.3167/th.2010.5712506"
- Description: This is a programmatic paper, calling for the renewal andmodernisation of the therapeutic approach to philosophy found inEpicureans, Stoics, and Skeptics; and, in particular, for an applicationof the therapeutic approach to the life of poverty. The general assump-tion behind a therapeutic approach to philosophy is that it is possiblefor someone to be exposed to philosophical work which leads her toan improved understanding of herself and her situation, and for herlife to be improved by this understanding. After offering a sketch ofhow, given the current nature of academic philosophy, such work willbe carried out and disseminated, I suggest three areas in which philo-sophical discourse could have a therapeutic affect on the poor.
- Full Text:
- Date Issued: 2010
Exploring the options for fuelwood policies to support poverty alleviation policies: Evolving dimensions in South Africa
- Shackleton, Charlie M, Buiten, Erik, Annecke, W, Banks, D, Bester, J, Everson, T, Fabricius, Christo, Ham, C, Kees, M, Modise, M, Phago, M, Prasad, Gisela, Twine, Wayne, Underwood, Michael, von Maltitz, Graham P, Wentzel, P
- Authors: Shackleton, Charlie M , Buiten, Erik , Annecke, W , Banks, D , Bester, J , Everson, T , Fabricius, Christo , Ham, C , Kees, M , Modise, M , Phago, M , Prasad, Gisela , Twine, Wayne , Underwood, Michael , von Maltitz, Graham P , Wentzel, P
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181213 , vital:43709 , xlink:href="https://doi.org/10.1080/14728028.2007.9752604"
- Description: Access to secure and affordable energy supplies is widely acknowledged as a critical foundation for sustainable development; inadequate access exacerbates household poverty. In the developing world poor households are frequently reliant upon fuel wood for all or most of their energy needs. However, national poverty alleviation policies commonly do not consider fuelwood within their strategies, and similarly, energy policies rarely consider the poverty alleviation potential of a comprehensive fuelwood strategy. Consequently, synergies between poverty alleviation and energy policies—with fuelwood (and its derivates) as the bridge—are needed. This paper discusses this potential using South Africa as a case example. The current policy environment that either favours or hinders a linkage between the poverty and energy sectors and policy options and strategies available to develop such links, are discussed.
- Full Text:
- Date Issued: 2007
- Authors: Shackleton, Charlie M , Buiten, Erik , Annecke, W , Banks, D , Bester, J , Everson, T , Fabricius, Christo , Ham, C , Kees, M , Modise, M , Phago, M , Prasad, Gisela , Twine, Wayne , Underwood, Michael , von Maltitz, Graham P , Wentzel, P
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181213 , vital:43709 , xlink:href="https://doi.org/10.1080/14728028.2007.9752604"
- Description: Access to secure and affordable energy supplies is widely acknowledged as a critical foundation for sustainable development; inadequate access exacerbates household poverty. In the developing world poor households are frequently reliant upon fuel wood for all or most of their energy needs. However, national poverty alleviation policies commonly do not consider fuelwood within their strategies, and similarly, energy policies rarely consider the poverty alleviation potential of a comprehensive fuelwood strategy. Consequently, synergies between poverty alleviation and energy policies—with fuelwood (and its derivates) as the bridge—are needed. This paper discusses this potential using South Africa as a case example. The current policy environment that either favours or hinders a linkage between the poverty and energy sectors and policy options and strategies available to develop such links, are discussed.
- Full Text:
- Date Issued: 2007
The role of land-based strategies in rural livelihoods: The contribution of arable production, animal husbandry and natural resource harvesting in communal areas in South Africa
- Shackleton, Charlie M, Shackleton, Sheona E, Cousins, Ben
- Authors: Shackleton, Charlie M , Shackleton, Sheona E , Cousins, Ben
- Date: 2001
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181651 , vital:43755 , xlink:href="https://doi.org/10.1080/03768350120097441"
- Description: Shackleton, C.M., Shackleton, S.E. and Cousins, B., 2001. The role of land-based strategies in rural livelihoods: the contribution of arable production, animal husbandry and natural resource harvesting in communal areas in South Africa. Development Southern Africa, 18(5), pp.581-604.
- Full Text:
- Date Issued: 2001
- Authors: Shackleton, Charlie M , Shackleton, Sheona E , Cousins, Ben
- Date: 2001
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181651 , vital:43755 , xlink:href="https://doi.org/10.1080/03768350120097441"
- Description: Shackleton, C.M., Shackleton, S.E. and Cousins, B., 2001. The role of land-based strategies in rural livelihoods: the contribution of arable production, animal husbandry and natural resource harvesting in communal areas in South Africa. Development Southern Africa, 18(5), pp.581-604.
- Full Text:
- Date Issued: 2001
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