Diverse values of nature for sustainability
- Pascual, Unai, Balvanera, Patricia, Anderson, Christopher B, Chaplin-Kramer, Rebecca, Christie, Michael, González-Jiménez, David, Martin, Adrian, Raymond, Christopher M, Termansen, Mette, Vatn, Arild, Athayde, Simone, Baptiste, Brigitte, Barton, Davind N, Jacobs, Sander, Kelemen, Eszter, Kumar, Ritesh, Lazos, Elena, Mwampamba, Tuyeni H, Nakangu, Barbara, O’Farrell, Patrick, Subramanian, Suneetha M, van Noordwijk, Meine, Ahn, SoEun, Amaruzaman, Sacha, Amin, Ariane M, Arias-Arévalo, Paola, Arroyo-Robles, Gabriela, Cantú-Fernández, Mariana, Castro, Antonio J, Contreras, Victoria, de Vos, Alta, Dendoncker, Nicolas, Engel, Stefanie, Eser, Uta, Faith, Daniel P, Filyushkina, Anna, Ghazi, Houda, Gómez-Baggethun, Erik, Gould, Rachelle K, Guibrunet, Louise, Gundimeda, Haripriya, Hahn, Thomas, Harmáčková, Zuzana V, Hernández-Blanco, Marcello, Horcea-Milcu, Andra-loana, Huambachano, Mariaelena, Wicher, Natalia L H, Aydın, Cem I, Islar, Mine, Koessler, Ann-Kathrin, Kenter, Jasper O, Kosmus, Marina, Lee, Heera, Leimona, Beria, Lele, Sharachchandra, Lenzi, Dominic, Lliso, Bosco, Mannetii, Lelani M, Merçon, Juliana, Monroy-Sais, Ana S, Mukherjee, Nibedita, Muraca, Barbara, Muradian, Roldan, Murali, Ranjini, Nelson, Sara H, Nemogá-Soto, Gabriel R, Ngouhouo-Poufoun, Jonas, Niamir, Aidin, Nuesiri, Emmanuel, Nyumba, Tobias O, Özkaynak, Begüm, Palomo, Ignacio, Pandit, Ram, Pawłowska-Mainville, Agnieszka, Porter-Bolland, Luciano, Quaas, Martin, Rode, Julian, Rozzi, Ricardo, Sachdeva, Sonya, Aibek, Samakov, Schaafsma, Marije, Sitas, Nadia, Ungar, Paula, Yiu, Evonne, Yoshida, Yuki, Zent, Eglee
- Authors: Pascual, Unai , Balvanera, Patricia , Anderson, Christopher B , Chaplin-Kramer, Rebecca , Christie, Michael , González-Jiménez, David , Martin, Adrian , Raymond, Christopher M , Termansen, Mette , Vatn, Arild , Athayde, Simone , Baptiste, Brigitte , Barton, Davind N , Jacobs, Sander , Kelemen, Eszter , Kumar, Ritesh , Lazos, Elena , Mwampamba, Tuyeni H , Nakangu, Barbara , O’Farrell, Patrick , Subramanian, Suneetha M , van Noordwijk, Meine , Ahn, SoEun , Amaruzaman, Sacha , Amin, Ariane M , Arias-Arévalo, Paola , Arroyo-Robles, Gabriela , Cantú-Fernández, Mariana , Castro, Antonio J , Contreras, Victoria , de Vos, Alta , Dendoncker, Nicolas , Engel, Stefanie , Eser, Uta , Faith, Daniel P , Filyushkina, Anna , Ghazi, Houda , Gómez-Baggethun, Erik , Gould, Rachelle K , Guibrunet, Louise , Gundimeda, Haripriya , Hahn, Thomas , Harmáčková, Zuzana V , Hernández-Blanco, Marcello , Horcea-Milcu, Andra-loana , Huambachano, Mariaelena , Wicher, Natalia L H , Aydın, Cem I , Islar, Mine , Koessler, Ann-Kathrin , Kenter, Jasper O , Kosmus, Marina , Lee, Heera , Leimona, Beria , Lele, Sharachchandra , Lenzi, Dominic , Lliso, Bosco , Mannetii, Lelani M , Merçon, Juliana , Monroy-Sais, Ana S , Mukherjee, Nibedita , Muraca, Barbara , Muradian, Roldan , Murali, Ranjini , Nelson, Sara H , Nemogá-Soto, Gabriel R , Ngouhouo-Poufoun, Jonas , Niamir, Aidin , Nuesiri, Emmanuel , Nyumba, Tobias O , Özkaynak, Begüm , Palomo, Ignacio , Pandit, Ram , Pawłowska-Mainville, Agnieszka , Porter-Bolland, Luciano , Quaas, Martin , Rode, Julian , Rozzi, Ricardo , Sachdeva, Sonya , Aibek, Samakov , Schaafsma, Marije , Sitas, Nadia , Ungar, Paula , Yiu, Evonne , Yoshida, Yuki , Zent, Eglee
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/415612 , vital:71270 , xlink:href="https://doi.org/10.1038/s41586-023-06406-9"
- Description: Twenty-five years since foundational publications on valuing ecosystem services for human well-being, addressing the global biodiversity crisis still implies confronting barriers to incorporating nature’s diverse values into decision-making. These barriers include powerful interests supported by current norms and legal rules such as property rights, which determine whose values and which values of nature are acted on. A better understanding of how and why nature is (under)valued is more urgent than ever. Notwithstanding agreements to incorporate nature’s values into actions, including the Kunming-Montreal Global Biodiversity Framework (GBF) and the UN Sustainable Development Goals, predominant environmental and development policies still prioritize a subset of values, particularly those linked to markets, and ignore other ways people relate to and benefit from nature. Arguably, a ‘values crisis’ underpins the intertwined crises of biodiversity loss and climate change, pandemic emergence and socio-environmental injustices. On the basis of more than 50,000 scientifc publications, policy documents and Indigenous and local knowledge sources, the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES) assessed knowledge on nature’s diverse values and valuation methods to gain insights into their role in policymaking and fuller integration into decisions. Applying this evidence, combinations of values-centred approaches are proposed to improve valuation and address barriers to uptake, ultimately leveraging transformative changes towards more just (that is, fair treatment of people and nature, including inter- and intragenerational equity) and sustainable futures.
- Full Text:
- Date Issued: 2023
- Authors: Pascual, Unai , Balvanera, Patricia , Anderson, Christopher B , Chaplin-Kramer, Rebecca , Christie, Michael , González-Jiménez, David , Martin, Adrian , Raymond, Christopher M , Termansen, Mette , Vatn, Arild , Athayde, Simone , Baptiste, Brigitte , Barton, Davind N , Jacobs, Sander , Kelemen, Eszter , Kumar, Ritesh , Lazos, Elena , Mwampamba, Tuyeni H , Nakangu, Barbara , O’Farrell, Patrick , Subramanian, Suneetha M , van Noordwijk, Meine , Ahn, SoEun , Amaruzaman, Sacha , Amin, Ariane M , Arias-Arévalo, Paola , Arroyo-Robles, Gabriela , Cantú-Fernández, Mariana , Castro, Antonio J , Contreras, Victoria , de Vos, Alta , Dendoncker, Nicolas , Engel, Stefanie , Eser, Uta , Faith, Daniel P , Filyushkina, Anna , Ghazi, Houda , Gómez-Baggethun, Erik , Gould, Rachelle K , Guibrunet, Louise , Gundimeda, Haripriya , Hahn, Thomas , Harmáčková, Zuzana V , Hernández-Blanco, Marcello , Horcea-Milcu, Andra-loana , Huambachano, Mariaelena , Wicher, Natalia L H , Aydın, Cem I , Islar, Mine , Koessler, Ann-Kathrin , Kenter, Jasper O , Kosmus, Marina , Lee, Heera , Leimona, Beria , Lele, Sharachchandra , Lenzi, Dominic , Lliso, Bosco , Mannetii, Lelani M , Merçon, Juliana , Monroy-Sais, Ana S , Mukherjee, Nibedita , Muraca, Barbara , Muradian, Roldan , Murali, Ranjini , Nelson, Sara H , Nemogá-Soto, Gabriel R , Ngouhouo-Poufoun, Jonas , Niamir, Aidin , Nuesiri, Emmanuel , Nyumba, Tobias O , Özkaynak, Begüm , Palomo, Ignacio , Pandit, Ram , Pawłowska-Mainville, Agnieszka , Porter-Bolland, Luciano , Quaas, Martin , Rode, Julian , Rozzi, Ricardo , Sachdeva, Sonya , Aibek, Samakov , Schaafsma, Marije , Sitas, Nadia , Ungar, Paula , Yiu, Evonne , Yoshida, Yuki , Zent, Eglee
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/415612 , vital:71270 , xlink:href="https://doi.org/10.1038/s41586-023-06406-9"
- Description: Twenty-five years since foundational publications on valuing ecosystem services for human well-being, addressing the global biodiversity crisis still implies confronting barriers to incorporating nature’s diverse values into decision-making. These barriers include powerful interests supported by current norms and legal rules such as property rights, which determine whose values and which values of nature are acted on. A better understanding of how and why nature is (under)valued is more urgent than ever. Notwithstanding agreements to incorporate nature’s values into actions, including the Kunming-Montreal Global Biodiversity Framework (GBF) and the UN Sustainable Development Goals, predominant environmental and development policies still prioritize a subset of values, particularly those linked to markets, and ignore other ways people relate to and benefit from nature. Arguably, a ‘values crisis’ underpins the intertwined crises of biodiversity loss and climate change, pandemic emergence and socio-environmental injustices. On the basis of more than 50,000 scientifc publications, policy documents and Indigenous and local knowledge sources, the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES) assessed knowledge on nature’s diverse values and valuation methods to gain insights into their role in policymaking and fuller integration into decisions. Applying this evidence, combinations of values-centred approaches are proposed to improve valuation and address barriers to uptake, ultimately leveraging transformative changes towards more just (that is, fair treatment of people and nature, including inter- and intragenerational equity) and sustainable futures.
- Full Text:
- Date Issued: 2023
Do thermal requirements of Dichrorampha odorata, a shoot-boring moth for the biological control of Chromolaena odorata, explain its failure to establish in South Africa?
- Nqayi, Slindile B, Zachariades, Costas, Coetzee, Julie A, Hill, Martin P, Chidwanyika, Frank, Uyi, Osariyekemwen O, McConnachie, Andrew J
- Authors: Nqayi, Slindile B , Zachariades, Costas , Coetzee, Julie A , Hill, Martin P , Chidwanyika, Frank , Uyi, Osariyekemwen O , McConnachie, Andrew J
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/416851 , vital:71391 , xlink:href="https://hdl.handle.net/10520/ejc-ento_v31_n1_a14"
- Description: Chromolaena odorata (L.) RM King and H Rob. (Asteraceae) has been subject to a biological control programme in South Africa for over three decades. A shoot-tip boring moth, Dichrorampha odorata Brown and Zachariades (Lepidoptera: Tortricidae), originating from Jamaica, was released as a biological control agent in 2013 but despite the release of substantial numbers of the insect, it has not established a permanent field population. Because climate incompatibility is a major constraint for classical biological control of invasive plants, and based on the differences in climate between Jamaica and South Africa and field observations at release sites, aspects of the thermal physiology of D. odorata were investigated to elucidate reasons for its failure to establish. Developmental time decreased with increasing temperatures ranging from 20 °C to 30 °C, with incomplete development for immature stages at 18 °C and 32 °C. The developmental threshold, t, was calculated as 8.45 °C with 872.4 degree-days required to complete development (K). A maximum of 6.5 generations per year was projected for D. odorata in South Africa, with the heavily infested eastern region of the country being the most eco-climatically suitable for establishment. The lower lethal temperature (LLT50) of larvae and adults was –4.5 and 1.8 °C, respectively. The upper lethal temperature (ULT50) for larvae was 39.6 °C whilst that of adults was 41.0 °C. Larvae thus had better cold tolerance compared to adults whereas adults had better heat tolerance compared to larvae. The critical thermal (CT) limits for adults were 3.4 ± 0.07 to 43.7 ± 0.12 °C. Acclimation at 20 °C for 7 days resulted in increased cold and heat tolerance with a CTmin and CTmax of 1.9 ± 0.06 and 44.4 ± 0.07 °C respectively, compared to the relative control, acclimated at 25 °C. Acclimation at 30 °C improved neither cold (CTmin: 5.9 ± 0.08 °C) nor heat tolerance (CTmax: 42.9 ± 0.10 °C). These results suggest that thermal requirements fall within field temperatures and are thus not the main constraining factor leading to poor establishment of D. odorata in South Africa.
- Full Text:
- Date Issued: 2023
- Authors: Nqayi, Slindile B , Zachariades, Costas , Coetzee, Julie A , Hill, Martin P , Chidwanyika, Frank , Uyi, Osariyekemwen O , McConnachie, Andrew J
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/416851 , vital:71391 , xlink:href="https://hdl.handle.net/10520/ejc-ento_v31_n1_a14"
- Description: Chromolaena odorata (L.) RM King and H Rob. (Asteraceae) has been subject to a biological control programme in South Africa for over three decades. A shoot-tip boring moth, Dichrorampha odorata Brown and Zachariades (Lepidoptera: Tortricidae), originating from Jamaica, was released as a biological control agent in 2013 but despite the release of substantial numbers of the insect, it has not established a permanent field population. Because climate incompatibility is a major constraint for classical biological control of invasive plants, and based on the differences in climate between Jamaica and South Africa and field observations at release sites, aspects of the thermal physiology of D. odorata were investigated to elucidate reasons for its failure to establish. Developmental time decreased with increasing temperatures ranging from 20 °C to 30 °C, with incomplete development for immature stages at 18 °C and 32 °C. The developmental threshold, t, was calculated as 8.45 °C with 872.4 degree-days required to complete development (K). A maximum of 6.5 generations per year was projected for D. odorata in South Africa, with the heavily infested eastern region of the country being the most eco-climatically suitable for establishment. The lower lethal temperature (LLT50) of larvae and adults was –4.5 and 1.8 °C, respectively. The upper lethal temperature (ULT50) for larvae was 39.6 °C whilst that of adults was 41.0 °C. Larvae thus had better cold tolerance compared to adults whereas adults had better heat tolerance compared to larvae. The critical thermal (CT) limits for adults were 3.4 ± 0.07 to 43.7 ± 0.12 °C. Acclimation at 20 °C for 7 days resulted in increased cold and heat tolerance with a CTmin and CTmax of 1.9 ± 0.06 and 44.4 ± 0.07 °C respectively, compared to the relative control, acclimated at 25 °C. Acclimation at 30 °C improved neither cold (CTmin: 5.9 ± 0.08 °C) nor heat tolerance (CTmax: 42.9 ± 0.10 °C). These results suggest that thermal requirements fall within field temperatures and are thus not the main constraining factor leading to poor establishment of D. odorata in South Africa.
- Full Text:
- Date Issued: 2023
Dual action of asymmetrical zinc (II) phthalocyanines conjugated to silver tungstate nanoparticles towards photodegradation of tetracycline and inactivation of Staphylococcus aureus bacteria
- Mgidlana, Sithi, Sen, Pinar, Nyokong, Tebello
- Authors: Mgidlana, Sithi , Sen, Pinar , Nyokong, Tebello
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/360400 , vital:65085 , xlink:href="https://doi.org/10.1016/j.jphotochem.2022.114444"
- Description: Asymmetric (A3B) Zn(II) phthalocyanines containing dimethoxy phenoxy as the dominant substituent and (phenoxy) propanoic acid (1), (phenoxy) acetic acid (2), and (phenoxy) acrylic acid (3) as the other substituents were synthesized and linked to silver tungstate nanoparticles (Ag2WO4 NPs). The photocatalytic activities of the prepared complexes 1–3 and nanoconjugates were evaluated for the photodegradation of tetracycline (TC) under visible-light irradiation and for photodynamic antimicrobial chemotherapy (PACT) activity against S. aureus. The results revealed that complex 3 had the best photocatalytic and PACT performance compared to 1 and 2, corresponding to the higher singlet oxygen quantum yield of the former in dimethyl sulfoxide. The photodegradation reaction was also examined using EPR and a mechanism for generation of singlet oxygen under visible light was confirmed. Photoinactivation of S. aureus improved in the presence of TC, when the two are applied together.
- Full Text:
- Date Issued: 2023
- Authors: Mgidlana, Sithi , Sen, Pinar , Nyokong, Tebello
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/360400 , vital:65085 , xlink:href="https://doi.org/10.1016/j.jphotochem.2022.114444"
- Description: Asymmetric (A3B) Zn(II) phthalocyanines containing dimethoxy phenoxy as the dominant substituent and (phenoxy) propanoic acid (1), (phenoxy) acetic acid (2), and (phenoxy) acrylic acid (3) as the other substituents were synthesized and linked to silver tungstate nanoparticles (Ag2WO4 NPs). The photocatalytic activities of the prepared complexes 1–3 and nanoconjugates were evaluated for the photodegradation of tetracycline (TC) under visible-light irradiation and for photodynamic antimicrobial chemotherapy (PACT) activity against S. aureus. The results revealed that complex 3 had the best photocatalytic and PACT performance compared to 1 and 2, corresponding to the higher singlet oxygen quantum yield of the former in dimethyl sulfoxide. The photodegradation reaction was also examined using EPR and a mechanism for generation of singlet oxygen under visible light was confirmed. Photoinactivation of S. aureus improved in the presence of TC, when the two are applied together.
- Full Text:
- Date Issued: 2023
Electrocatalytic Behavior of Manganese and Cobalt Porphyrins Attached to Graphene Quantum Dots: Applied in the Oxidation of Hydrazine
- Jokazi, Mbulelo, Mpeta, Lekhetho S, Nyokong, Tebello
- Authors: Jokazi, Mbulelo , Mpeta, Lekhetho S , Nyokong, Tebello
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/360411 , vital:65086 , xlink:href="https://doi.org/10.1002/elan.202200222"
- Description: Manganese and cobalt metalated 5, 10, 15-tris(aminophenyl)-20-(4-carboxyphenyl) porphyrins (ClMnTA3CPP and CoTA3CPP) were synthesized and attached to graphene quantum dots (GQDs) via π-π interaction and electrostatic interaction. The electrochemical oxidation of hydrazine was performed via cyclic voltammetry and chronoamperometry. The CoTA3CPP showed good electrocatalytic activity towards the oxidation of hydrazine in terms of catalytic rate constants and limits of detection (LoD). ClMnTA3CPP showed lower overpotential 0.60 V. The introduction of GQDs improved the electrocatalytic ability when combined with CoTA3CPP and ClMnTA3CPP with the lowest LoD (0.0025 mM CoTA3CPP–GQDs) followed by ClMnTA3CPP–GQDs with 0.0033 mM.
- Full Text:
- Date Issued: 2023
- Authors: Jokazi, Mbulelo , Mpeta, Lekhetho S , Nyokong, Tebello
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/360411 , vital:65086 , xlink:href="https://doi.org/10.1002/elan.202200222"
- Description: Manganese and cobalt metalated 5, 10, 15-tris(aminophenyl)-20-(4-carboxyphenyl) porphyrins (ClMnTA3CPP and CoTA3CPP) were synthesized and attached to graphene quantum dots (GQDs) via π-π interaction and electrostatic interaction. The electrochemical oxidation of hydrazine was performed via cyclic voltammetry and chronoamperometry. The CoTA3CPP showed good electrocatalytic activity towards the oxidation of hydrazine in terms of catalytic rate constants and limits of detection (LoD). ClMnTA3CPP showed lower overpotential 0.60 V. The introduction of GQDs improved the electrocatalytic ability when combined with CoTA3CPP and ClMnTA3CPP with the lowest LoD (0.0025 mM CoTA3CPP–GQDs) followed by ClMnTA3CPP–GQDs with 0.0033 mM.
- Full Text:
- Date Issued: 2023
Evaluation of the antibacterial activity of gallic acid anchored phthalocyanine-doped silica nanoparticles towards Escherichia coli and Staphylococcus aureus biofilms and planktonic cells
- Magadla, Aviwe, Openda, Yolande Ikala, Mpeta, Lekhetho S, Nyokong, Tebello
- Authors: Magadla, Aviwe , Openda, Yolande Ikala , Mpeta, Lekhetho S , Nyokong, Tebello
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/360424 , vital:65087 , xlink:href="https://doi.org/10.1016/j.pdpdt.2023.103520"
- Description: In this work, we have described the synthesis of phthalocyanine complexes Zn(II) tetrakis 4-(5-formylpyridin-2-yl)oxy) phthalocyanine (2), Zn(II) tetrakis-1 butyl 4-(2-(6- (tetra-phenoxy)pyridin-3-yl) vinyl)pyridin-1-ium phthalocyanine (3) and Zn(II) tetrakis 1 butyl 5-(2-(1-butylpyridin-1-ium-4-yl)vinyl)-2-(tetra-phenoxy)pyridin-1-ium phthalocyanine (4). The effect of a varying number of charges when the Pc complexes are alone or grafted in gallic acid (GA) tagged silica nanoparticles on photodynamic antimicrobial chemotherapy (PACT) is investigated toward Staphylococcus aureus (S.aureus) and Escherichia coli (E.coli) in both planktonic and biofilm forms. Complex 4, bearing a total of 8 cationic charges, displayed the highest activity with log CFU (colony forming units) values of 8.60 and 6.42 against E.coli and S.aureus biofilms, respectively. The surface stability of E.coli and S.aureus biofilms in the presence of 4 and its conjugate was analyzed using cyclic voltammetry. Scanning electron microscopy (SEM) and Raman spectra are also used to study the conformational and biochemical changes within biofilm upon subjecting them to PACT.
- Full Text:
- Date Issued: 2023
- Authors: Magadla, Aviwe , Openda, Yolande Ikala , Mpeta, Lekhetho S , Nyokong, Tebello
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/360424 , vital:65087 , xlink:href="https://doi.org/10.1016/j.pdpdt.2023.103520"
- Description: In this work, we have described the synthesis of phthalocyanine complexes Zn(II) tetrakis 4-(5-formylpyridin-2-yl)oxy) phthalocyanine (2), Zn(II) tetrakis-1 butyl 4-(2-(6- (tetra-phenoxy)pyridin-3-yl) vinyl)pyridin-1-ium phthalocyanine (3) and Zn(II) tetrakis 1 butyl 5-(2-(1-butylpyridin-1-ium-4-yl)vinyl)-2-(tetra-phenoxy)pyridin-1-ium phthalocyanine (4). The effect of a varying number of charges when the Pc complexes are alone or grafted in gallic acid (GA) tagged silica nanoparticles on photodynamic antimicrobial chemotherapy (PACT) is investigated toward Staphylococcus aureus (S.aureus) and Escherichia coli (E.coli) in both planktonic and biofilm forms. Complex 4, bearing a total of 8 cationic charges, displayed the highest activity with log CFU (colony forming units) values of 8.60 and 6.42 against E.coli and S.aureus biofilms, respectively. The surface stability of E.coli and S.aureus biofilms in the presence of 4 and its conjugate was analyzed using cyclic voltammetry. Scanning electron microscopy (SEM) and Raman spectra are also used to study the conformational and biochemical changes within biofilm upon subjecting them to PACT.
- Full Text:
- Date Issued: 2023
Examining the implementation of the Department of Social Development’s fatherhood strategy by FAMSA
- Authors: Sishuba, Thozama Alicia
- Date: 2023
- Subjects: Grahamstown (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/27618 , vital:69320
- Description: This study aimed to exam the implementation of the Department of Social Development’s Fatherhood Strategy by Families South Africa (FAMSA) Eastern Cape. FAMSA is a non-profit organization providing vital services to people in families while providing them with psychosocial and emotional support. FAMSA has been in existence since 1954. To achieve this aim, the study’s objectives were underpinned by understanding the implementation of the Department of Social Development’s Fatherhood Strategy in Buffalo City Metro, establishing FAMSA’s response to the implementation of the Department of Social Development’s Fatherhood Strategy as well as exploring the challenges faced by FAMSA in implementing the Department of Social Development’s Fatherhood Strategy. A qualitative research methodology was implemented to gather information from FAMSA and DSD. Findings from literature revealed that the fatherhood strategy has been a concern worldwide evidenced by the high levels of father-child non-residency. Data from this study revealed that FAMSA had been implementing the programme effectively regardless of numerous challenges that include funding human resources. Conclusively, a lot must be done to advocate for fatherhood. Recommendations also point to the need for several interventions which need to be done in research, social work practice and also policy formulation and development. , Thesis (MA) -- Faculty of Social Sciences and Humanities, 2023
- Full Text:
- Date Issued: 2023
- Authors: Sishuba, Thozama Alicia
- Date: 2023
- Subjects: Grahamstown (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/27618 , vital:69320
- Description: This study aimed to exam the implementation of the Department of Social Development’s Fatherhood Strategy by Families South Africa (FAMSA) Eastern Cape. FAMSA is a non-profit organization providing vital services to people in families while providing them with psychosocial and emotional support. FAMSA has been in existence since 1954. To achieve this aim, the study’s objectives were underpinned by understanding the implementation of the Department of Social Development’s Fatherhood Strategy in Buffalo City Metro, establishing FAMSA’s response to the implementation of the Department of Social Development’s Fatherhood Strategy as well as exploring the challenges faced by FAMSA in implementing the Department of Social Development’s Fatherhood Strategy. A qualitative research methodology was implemented to gather information from FAMSA and DSD. Findings from literature revealed that the fatherhood strategy has been a concern worldwide evidenced by the high levels of father-child non-residency. Data from this study revealed that FAMSA had been implementing the programme effectively regardless of numerous challenges that include funding human resources. Conclusively, a lot must be done to advocate for fatherhood. Recommendations also point to the need for several interventions which need to be done in research, social work practice and also policy formulation and development. , Thesis (MA) -- Faculty of Social Sciences and Humanities, 2023
- Full Text:
- Date Issued: 2023
Fruits of the city: The nature, nurture and future of urban foraging
- Sardeshpande, Mallika, Shackleton, Charlie M
- Authors: Sardeshpande, Mallika , Shackleton, Charlie M
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/402259 , vital:69835 , xlink:href="https://doi.org/10.1002/pan3.10428"
- Description: Urban foraging is a global informal phenomenon which has been investigated in the Global North more than oth-er parts of the world. Characterising the nature of urban foraging in the Global South is imperative given the rapid urbanisation and sustainable development priorities in the region. In this study, we interviewed 80 urban forag-ers in four cities in the eastern coastal region of South Af-rica, with an aim to understand the nature of urban forag-ing in a developing nation context. We asked foragers about their initiation to and motivations for foraging, their logistics, yields and associated activities, descriptions of their foraging grounds, and if and how they had changed, and what they envisage as an ideal future for foraging.
- Full Text:
- Date Issued: 2023
- Authors: Sardeshpande, Mallika , Shackleton, Charlie M
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/402259 , vital:69835 , xlink:href="https://doi.org/10.1002/pan3.10428"
- Description: Urban foraging is a global informal phenomenon which has been investigated in the Global North more than oth-er parts of the world. Characterising the nature of urban foraging in the Global South is imperative given the rapid urbanisation and sustainable development priorities in the region. In this study, we interviewed 80 urban forag-ers in four cities in the eastern coastal region of South Af-rica, with an aim to understand the nature of urban forag-ing in a developing nation context. We asked foragers about their initiation to and motivations for foraging, their logistics, yields and associated activities, descriptions of their foraging grounds, and if and how they had changed, and what they envisage as an ideal future for foraging.
- Full Text:
- Date Issued: 2023
History matters: Societal acceptance of deep-sea mining and incipient conflicts in Papua New Guinea
- van Putten, Ingrid, Shankar, Aswani, Boonstra, W.J, De la Cruz-Modino, R, Das, Jewel, Glaser, Marion, Heck, Nadine, Narayan, Siddharth, Paytan, Adina, Selim, Samiya, Vave, Ron
- Authors: van Putten, Ingrid , Shankar, Aswani , Boonstra, W.J , De la Cruz-Modino, R , Das, Jewel , Glaser, Marion , Heck, Nadine , Narayan, Siddharth , Paytan, Adina , Selim, Samiya , Vave, Ron
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/391453 , vital:68653 , xlink:href="https://doi.org/10.1007/s40152-023-00318-0"
- Description: New marine industries that develop and grow in response to the changing demand for their products have the potential to exert pressure on fragile marine environments. These emerging industries can benefit local communities but equally can have negative environmental and socio-cultural impacts. The development of new and emerging industries, like deep seabed mining (DSM), requires the acceptance and involvement of local communities. Yet, the history of marine exploitation is imbued with conflicts between industries and local communities. This paper presents a DSM case study in Papua New Guinea (PNG) to stimulate debate around the potential for conflict in the pursuit of resource extraction from the deep sea and the social and environmental harm that these extractions can cause. We do so by first presenting a timeline of local and extra-local events and enabling conditions that form the development background for the DSM Solwara 1 project in PNG. We then undertake a media narrative analysis to consider the contribution of aspects of social acceptability to this highly complex and multi-scale conflict. We find that the lack of (or a decrease in) social acceptability contributed to the conflict situation and ultimately the demise of the Solwara 1 project. Extra-locally, the initial development was positively framed around solutions for decarbonisation using new technology. Over time, actions by international NGOs, financial issues related to foreign companies, and asymmetry in the power balance between the Pacific Island nation and global businesses played a role in growing negative perceptions of acceptability. Historical experiences with prior environmental mining disasters, together with sea tenure governance challenges, and a lack of community and stakeholder acceptance also contributed to the demise of the project. Untangling and debating these complex interactions provides context and reasons for the tension between the lack of societal acceptance at a local scale and the perceived need for DSM products in the global North for innovative technologies and decarbonising societies. Better understanding these interactions and tensions can help emerging industries navigate a future blue economy.
- Full Text:
- Date Issued: 2023
- Authors: van Putten, Ingrid , Shankar, Aswani , Boonstra, W.J , De la Cruz-Modino, R , Das, Jewel , Glaser, Marion , Heck, Nadine , Narayan, Siddharth , Paytan, Adina , Selim, Samiya , Vave, Ron
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/391453 , vital:68653 , xlink:href="https://doi.org/10.1007/s40152-023-00318-0"
- Description: New marine industries that develop and grow in response to the changing demand for their products have the potential to exert pressure on fragile marine environments. These emerging industries can benefit local communities but equally can have negative environmental and socio-cultural impacts. The development of new and emerging industries, like deep seabed mining (DSM), requires the acceptance and involvement of local communities. Yet, the history of marine exploitation is imbued with conflicts between industries and local communities. This paper presents a DSM case study in Papua New Guinea (PNG) to stimulate debate around the potential for conflict in the pursuit of resource extraction from the deep sea and the social and environmental harm that these extractions can cause. We do so by first presenting a timeline of local and extra-local events and enabling conditions that form the development background for the DSM Solwara 1 project in PNG. We then undertake a media narrative analysis to consider the contribution of aspects of social acceptability to this highly complex and multi-scale conflict. We find that the lack of (or a decrease in) social acceptability contributed to the conflict situation and ultimately the demise of the Solwara 1 project. Extra-locally, the initial development was positively framed around solutions for decarbonisation using new technology. Over time, actions by international NGOs, financial issues related to foreign companies, and asymmetry in the power balance between the Pacific Island nation and global businesses played a role in growing negative perceptions of acceptability. Historical experiences with prior environmental mining disasters, together with sea tenure governance challenges, and a lack of community and stakeholder acceptance also contributed to the demise of the project. Untangling and debating these complex interactions provides context and reasons for the tension between the lack of societal acceptance at a local scale and the perceived need for DSM products in the global North for innovative technologies and decarbonising societies. Better understanding these interactions and tensions can help emerging industries navigate a future blue economy.
- Full Text:
- Date Issued: 2023
Host-specificity testing of the leaf-feeding flea beetle, Phenrica guerini, a biological control agent for the invasive alien cactus, Pereskia aculeata
- Dixon, Elizabeth, Paterson, Iain D, Muskett, Philippa, McConnachie, Andrew J
- Authors: Dixon, Elizabeth , Paterson, Iain D , Muskett, Philippa , McConnachie, Andrew J
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/417713 , vital:71480 , xlink:href="https://doi.org/10.1080/09583157.2023.2214342"
- Description: Pereskia aculeata Miller (Cactaceae) is an environmentally damaging invasive alien plant in South Africa and Australia. The flea-beetle, Phenrica guerini Bechyné (Coleoptera: Chrysomelidae), has been used in South Africa as a biological control agent against the plant for more than 30 years but updated host-specificity testing was required to determine its suitability as an agent in Australia. No-choice larval survival tests were conducted on 26 test plant species from 11 families, with survival to the adult stage only being recorded on the target weed, P. aculeata. No-choice oviposition testing with adult P. guerini was conducted on six test plant species. No adult feeding was recorded on any test plants and significantly more eggs were oviposited on P. aculeata (158.8 SE ± 21.4) than on Talinum caffrum (5.2 SE ± 5.2), which was the only test plant on which they oviposited. The adults survived on average 27 days longer on P. aculeata than on any test plant species. In a multiple-choice trial that included all three species that supported any larval feeding as well as P. aculeata, oviposition and feeding was only recorded on target weed. Phenrica guerini is suitably host specific for consideration in Australia as a biological control agent against P. aculeata.
- Full Text:
- Date Issued: 2023
- Authors: Dixon, Elizabeth , Paterson, Iain D , Muskett, Philippa , McConnachie, Andrew J
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/417713 , vital:71480 , xlink:href="https://doi.org/10.1080/09583157.2023.2214342"
- Description: Pereskia aculeata Miller (Cactaceae) is an environmentally damaging invasive alien plant in South Africa and Australia. The flea-beetle, Phenrica guerini Bechyné (Coleoptera: Chrysomelidae), has been used in South Africa as a biological control agent against the plant for more than 30 years but updated host-specificity testing was required to determine its suitability as an agent in Australia. No-choice larval survival tests were conducted on 26 test plant species from 11 families, with survival to the adult stage only being recorded on the target weed, P. aculeata. No-choice oviposition testing with adult P. guerini was conducted on six test plant species. No adult feeding was recorded on any test plants and significantly more eggs were oviposited on P. aculeata (158.8 SE ± 21.4) than on Talinum caffrum (5.2 SE ± 5.2), which was the only test plant on which they oviposited. The adults survived on average 27 days longer on P. aculeata than on any test plant species. In a multiple-choice trial that included all three species that supported any larval feeding as well as P. aculeata, oviposition and feeding was only recorded on target weed. Phenrica guerini is suitably host specific for consideration in Australia as a biological control agent against P. aculeata.
- Full Text:
- Date Issued: 2023
Host-specificity testing of the leaf-feeding flea beetle, Phenrica guerini, a biological control agent for the invasive alien cactus, Pereskia aculeata
- Dixon, Elizabeth, Paterson, Iain D, Muskett, Philippa, McConnachie, Andrew
- Authors: Dixon, Elizabeth , Paterson, Iain D , Muskett, Philippa , McConnachie, Andrew
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/417687 , vital:71478 , xlink:href="https://doi.org/10.1080/09583157.2023.2214342"
- Description: Pereskia aculeata Miller (Cactaceae) is an environmentally damaging invasive alien plant in South Africa and Australia. The flea-beetle, Phenrica guerini Bechyné (Coleoptera: Chrysomelidae), has been used in South Africa as a biological control agent against the plant for more than 30 years but updated host-specificity testing was required to determine its suitability as an agent in Australia. No-choice larval survival tests were conducted on 26 test plant species from 11 families, with survival to the adult stage only being recorded on the target weed, P. aculeata. No-choice oviposition testing with adult P. guerini was conducted on six test plant species. No adult feeding was recorded on any test plants and significantly more eggs were oviposited on P. aculeata (158.8 SE ± 21.4) than on Talinum caffrum (5.2 SE ± 5.2), which was the only test plant on which they oviposited. The adults survived on average 27 days longer on P. aculeata than on any test plant species. In a multiple-choice trial that included all three species that supported any larval feeding as well as P. aculeata, oviposition and feeding was only recorded on target weed. Phenrica guerini is suitably host specific for consideration in Australia as a biological control agent against P. aculeata.
- Full Text:
- Date Issued: 2023
- Authors: Dixon, Elizabeth , Paterson, Iain D , Muskett, Philippa , McConnachie, Andrew
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/417687 , vital:71478 , xlink:href="https://doi.org/10.1080/09583157.2023.2214342"
- Description: Pereskia aculeata Miller (Cactaceae) is an environmentally damaging invasive alien plant in South Africa and Australia. The flea-beetle, Phenrica guerini Bechyné (Coleoptera: Chrysomelidae), has been used in South Africa as a biological control agent against the plant for more than 30 years but updated host-specificity testing was required to determine its suitability as an agent in Australia. No-choice larval survival tests were conducted on 26 test plant species from 11 families, with survival to the adult stage only being recorded on the target weed, P. aculeata. No-choice oviposition testing with adult P. guerini was conducted on six test plant species. No adult feeding was recorded on any test plants and significantly more eggs were oviposited on P. aculeata (158.8 SE ± 21.4) than on Talinum caffrum (5.2 SE ± 5.2), which was the only test plant on which they oviposited. The adults survived on average 27 days longer on P. aculeata than on any test plant species. In a multiple-choice trial that included all three species that supported any larval feeding as well as P. aculeata, oviposition and feeding was only recorded on target weed. Phenrica guerini is suitably host specific for consideration in Australia as a biological control agent against P. aculeata.
- Full Text:
- Date Issued: 2023
Impact of Access and Benefit Sharing implementation on biological control genetic resources
- Mason, Peter G, Barratt, Barbara I P, Mc Kay, Fernando, Klapwijk, Johannette N, Silvestri, Luciano C, Hill, Martin P, Hinz, Hariet L, Sheppard, Andy, Brodeur, Jacques, Vitorino, Marcello Diniz, Weyl, Philip S R, Hoelmer, Kim A
- Authors: Mason, Peter G , Barratt, Barbara I P , Mc Kay, Fernando , Klapwijk, Johannette N , Silvestri, Luciano C , Hill, Martin P , Hinz, Hariet L , Sheppard, Andy , Brodeur, Jacques , Vitorino, Marcello Diniz , Weyl, Philip S R , Hoelmer, Kim A
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/418013 , vital:71501 , xlink:href="https://doi.org/10.1007/s10526-023-10176-8"
- Description: The third objective of the Convention on Biological Diversity, the fair and equitable sharing of benefits arising out of the use of genetic resources was further developed when the Nagoya Protocol on Access and Benefit Sharing came into effect in 2014. Interpretation of how this agreement is being implemented is wide-ranging and there are implications for biological control. A survey of biological control workers indicated that while some countries have facilitated access to biological control genetic resources, requirements in other countries have impeded biological control implementation. There was consensus that benefits to provider countries should be in the form of supporting local research communities. There was also agreement that the free use and exchange of biological control genetic resources has provided benefits to the global community, including to both providers and recipients of the agents. It is recommended that consideration of the free use and exchange principal should be a key element of Access and Benefit Sharing measures for the future.
- Full Text:
- Date Issued: 2023
- Authors: Mason, Peter G , Barratt, Barbara I P , Mc Kay, Fernando , Klapwijk, Johannette N , Silvestri, Luciano C , Hill, Martin P , Hinz, Hariet L , Sheppard, Andy , Brodeur, Jacques , Vitorino, Marcello Diniz , Weyl, Philip S R , Hoelmer, Kim A
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/418013 , vital:71501 , xlink:href="https://doi.org/10.1007/s10526-023-10176-8"
- Description: The third objective of the Convention on Biological Diversity, the fair and equitable sharing of benefits arising out of the use of genetic resources was further developed when the Nagoya Protocol on Access and Benefit Sharing came into effect in 2014. Interpretation of how this agreement is being implemented is wide-ranging and there are implications for biological control. A survey of biological control workers indicated that while some countries have facilitated access to biological control genetic resources, requirements in other countries have impeded biological control implementation. There was consensus that benefits to provider countries should be in the form of supporting local research communities. There was also agreement that the free use and exchange of biological control genetic resources has provided benefits to the global community, including to both providers and recipients of the agents. It is recommended that consideration of the free use and exchange principal should be a key element of Access and Benefit Sharing measures for the future.
- Full Text:
- Date Issued: 2023
International agreement for the use and exchange of classical biological control genetic resources: a practical proposal
- Mason, Peter G, Mc Kay, Fernando, Silvestri, Luciano C, Hill, Martin P, Weyl, Philip S R, Hinz, Hariet L, Brodeur, Jacques, Vitorino, Marcello Diniz, Barratt, Barbara I P
- Authors: Mason, Peter G , Mc Kay, Fernando , Silvestri, Luciano C , Hill, Martin P , Weyl, Philip S R , Hinz, Hariet L , Brodeur, Jacques , Vitorino, Marcello Diniz , Barratt, Barbara I P
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/418025 , vital:71502 , xlink:href="https://doi.org/10.1007/s10526-023-10177-7"
- Description: The Nagoya Protocol on Access and Benefit Sharing (ABS) was implemented to further develop the third objective of the Convention on Biological Diversity, the fair and equitable sharing of benefits arising out of the utilization of genetic resources. Interpretation of this agreement is wide-ranging and there is concern that if ABS measures are poorly implemented biological control and the resultant public good will be greatly impeded. The ethos of multilateral use and exchange of genetic resources used in classical biological control will be particularly affected. In the spirit of the fair and equitable sharing of benefits arising out of the utilization of genetic resources, we propose a simple practical solution in the form of an international agreement on the use and exchange of classical biological control genetic resources.
- Full Text:
- Date Issued: 2023
- Authors: Mason, Peter G , Mc Kay, Fernando , Silvestri, Luciano C , Hill, Martin P , Weyl, Philip S R , Hinz, Hariet L , Brodeur, Jacques , Vitorino, Marcello Diniz , Barratt, Barbara I P
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/418025 , vital:71502 , xlink:href="https://doi.org/10.1007/s10526-023-10177-7"
- Description: The Nagoya Protocol on Access and Benefit Sharing (ABS) was implemented to further develop the third objective of the Convention on Biological Diversity, the fair and equitable sharing of benefits arising out of the utilization of genetic resources. Interpretation of this agreement is wide-ranging and there is concern that if ABS measures are poorly implemented biological control and the resultant public good will be greatly impeded. The ethos of multilateral use and exchange of genetic resources used in classical biological control will be particularly affected. In the spirit of the fair and equitable sharing of benefits arising out of the utilization of genetic resources, we propose a simple practical solution in the form of an international agreement on the use and exchange of classical biological control genetic resources.
- Full Text:
- Date Issued: 2023
Investigation into response of wheat genotypes to drought and optimum conditions in the Eastern Cape Province, South Africa
- Authors: Mzileni L S
- Date: 2023
- Subjects: Bonanza farms , Wheat , Drought - tolerant plants
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/27732 , vital:69397
- Description: Wheat is generally one of the dominant crops globally, being mainly used for human food and livestock feed. Due to climate change, drought makes it challenging to produce enough wheat mostly under dryland production regions in South Africa. Drought stress has severely reduced wheat yield by up to 70 percent, and adversely compromised wheat grain quality. The adoption of drought-tolerant cultivars offers a sustainable and low-cost solution for increasing wheat yields and minimise importing the crop to meet national requirements. The main objective of this study was to investigate the response of different wheat genotypes to drought and optimum conditions in the Eastern Cape Province, South Africa. Forty diverse wheat genotypes were evaluated in this study. The specific objectives were: (i) to evaluate the response of wheat genotypes under optimum and drought-stressed field conditions; (ii) to determine the effect of terminal drought stress on wheat grain quality composition; and (iii) to identify appropriate drought tolerance indices that can be used as selection tools under field conditions. This study was conducted in the field using a 5x8 alpha lattice design, replicated twice under two water regimes (drought and optimum) over two consecutive winter seasons of 2020 and 2021 at two different sites namely University of Fort Hare Research Farm in Alice, and Zanyokwe irrigation scheme in Keiskamahoek. Drought stress was imposed from 50% flowering up to physiological maturity. Data on agro-physiological traits such as duration to heading (DTH); flowering (DTF); maturity (DTM); plant height (HT); spike length (SL); number of spikelets per spike (SPS); kernels per spike (KPS); and grain yield (GY (kg/ha)) was subjected to the analysis of variance using Genstat 18th edition. As the study took place over two sites, a combined ANOVA table revealed significant differences (p0.001) among genotypes, and all interactions such as genotype by water regime (GWR); genotype by seasons (GS) for all studied traits. Notably, the extent and severity of drought differed between geographical regions and between seasons. This necessitated the adoption of the additive main effect and multiplicative interaction analysis (AMMI) for the identification of stable genotypes under two different water regimes over two sites. Regarding grain yield, superior and/or stable genotypes included G5 (4334 kg/ha under optimum, and 2871kg/ha under drought), and G22 (4418 kg/ha under optimum, and 2624kg/ha under drought) at the UFH site. G21 (3194 kg/ha under optimum, and 2938 kg/ha under drought), G33 (2552kg/ha under optimum, and 3810 kg/ha under drought), and G35 (2688 kg/ha under optimum, and 3309 kg/ha under drought) at the ZAN site. Stable genotypes across sites included G21 and G33. There were generally weak correlations between agro-physiological traits and grain yield. From the experiment, grain quality traits such as fixed protein (PF); wet gluten (WG); hectolitre mass (HLM); and thousand kernel weight (TKW) were also examined. A combined ANOVA revealed significant differences (p0.001) among the interaction of genotypes by environments (GE) for all traits except PF. This implies that the performance of wheat genotypes across sites was also different, and therefore, necessitated separate analysis of variance for each site. Significant differences (p0.001) among genotypes (G), water regimes (WR), and the interaction of genotypes by water regime (GWR) were observed for all studied quality traits except PF in both sites. GWR showed no significant differences for TKW in the ZAN site. The stability in the performance of genotypes across water regimes was further determined. G38 was stable for wet gluten; G31 and G26 were stable for PF; G36 was stable for HLM; and G11, G15, and G29 were stable for TKW at the UFH site. G6 was stable for both WG and PF; G13 and G15 were stable for HLM; and G35, G21, and G40 were stable for TKW at the ZAN site. These results suggest that the quality of wheat grains was affected under drought stress conditions except PF. Average grain yield data under both stressed (Ys) and optimum (Yp) conditions was used to compute a number of different drought tolerance indices. These include mean productivity (MP); geometric mean productivity (GMP); harmonic mean (HM); Tolerance index (TOL), stress susceptible index (SSI), sensitive drought index (SDI), and stress tolerance index (STI). The aim was to identify appropriate drought tolerance indices that can be used as selection tools under drought stress. MP, GMP, and HM were the more appropriate indices as they had a strong and positive correlation with grain yield under both drought and optimum conditions. However, genotypes G5, G22, G8, and G21 were more tolerant and stable as they showed high mean values. Based on the results, G19, G16, G2, and G20 were more sensitive to drought as they showed low values of MP, GMP, and HM. Overall, genotype: G5, G21, G22, and G33 are recommended for production under drought and optimum conditions, as they showed stable performance across water regimes. Principal component analysis also revealed that MP, GMP, and HM were the only indices that had positive loadings into the first principal component. , Thesis (MSc) -- Faculty of Science and Agriculture, 2023
- Full Text:
- Date Issued: 2023
- Authors: Mzileni L S
- Date: 2023
- Subjects: Bonanza farms , Wheat , Drought - tolerant plants
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/27732 , vital:69397
- Description: Wheat is generally one of the dominant crops globally, being mainly used for human food and livestock feed. Due to climate change, drought makes it challenging to produce enough wheat mostly under dryland production regions in South Africa. Drought stress has severely reduced wheat yield by up to 70 percent, and adversely compromised wheat grain quality. The adoption of drought-tolerant cultivars offers a sustainable and low-cost solution for increasing wheat yields and minimise importing the crop to meet national requirements. The main objective of this study was to investigate the response of different wheat genotypes to drought and optimum conditions in the Eastern Cape Province, South Africa. Forty diverse wheat genotypes were evaluated in this study. The specific objectives were: (i) to evaluate the response of wheat genotypes under optimum and drought-stressed field conditions; (ii) to determine the effect of terminal drought stress on wheat grain quality composition; and (iii) to identify appropriate drought tolerance indices that can be used as selection tools under field conditions. This study was conducted in the field using a 5x8 alpha lattice design, replicated twice under two water regimes (drought and optimum) over two consecutive winter seasons of 2020 and 2021 at two different sites namely University of Fort Hare Research Farm in Alice, and Zanyokwe irrigation scheme in Keiskamahoek. Drought stress was imposed from 50% flowering up to physiological maturity. Data on agro-physiological traits such as duration to heading (DTH); flowering (DTF); maturity (DTM); plant height (HT); spike length (SL); number of spikelets per spike (SPS); kernels per spike (KPS); and grain yield (GY (kg/ha)) was subjected to the analysis of variance using Genstat 18th edition. As the study took place over two sites, a combined ANOVA table revealed significant differences (p0.001) among genotypes, and all interactions such as genotype by water regime (GWR); genotype by seasons (GS) for all studied traits. Notably, the extent and severity of drought differed between geographical regions and between seasons. This necessitated the adoption of the additive main effect and multiplicative interaction analysis (AMMI) for the identification of stable genotypes under two different water regimes over two sites. Regarding grain yield, superior and/or stable genotypes included G5 (4334 kg/ha under optimum, and 2871kg/ha under drought), and G22 (4418 kg/ha under optimum, and 2624kg/ha under drought) at the UFH site. G21 (3194 kg/ha under optimum, and 2938 kg/ha under drought), G33 (2552kg/ha under optimum, and 3810 kg/ha under drought), and G35 (2688 kg/ha under optimum, and 3309 kg/ha under drought) at the ZAN site. Stable genotypes across sites included G21 and G33. There were generally weak correlations between agro-physiological traits and grain yield. From the experiment, grain quality traits such as fixed protein (PF); wet gluten (WG); hectolitre mass (HLM); and thousand kernel weight (TKW) were also examined. A combined ANOVA revealed significant differences (p0.001) among the interaction of genotypes by environments (GE) for all traits except PF. This implies that the performance of wheat genotypes across sites was also different, and therefore, necessitated separate analysis of variance for each site. Significant differences (p0.001) among genotypes (G), water regimes (WR), and the interaction of genotypes by water regime (GWR) were observed for all studied quality traits except PF in both sites. GWR showed no significant differences for TKW in the ZAN site. The stability in the performance of genotypes across water regimes was further determined. G38 was stable for wet gluten; G31 and G26 were stable for PF; G36 was stable for HLM; and G11, G15, and G29 were stable for TKW at the UFH site. G6 was stable for both WG and PF; G13 and G15 were stable for HLM; and G35, G21, and G40 were stable for TKW at the ZAN site. These results suggest that the quality of wheat grains was affected under drought stress conditions except PF. Average grain yield data under both stressed (Ys) and optimum (Yp) conditions was used to compute a number of different drought tolerance indices. These include mean productivity (MP); geometric mean productivity (GMP); harmonic mean (HM); Tolerance index (TOL), stress susceptible index (SSI), sensitive drought index (SDI), and stress tolerance index (STI). The aim was to identify appropriate drought tolerance indices that can be used as selection tools under drought stress. MP, GMP, and HM were the more appropriate indices as they had a strong and positive correlation with grain yield under both drought and optimum conditions. However, genotypes G5, G22, G8, and G21 were more tolerant and stable as they showed high mean values. Based on the results, G19, G16, G2, and G20 were more sensitive to drought as they showed low values of MP, GMP, and HM. Overall, genotype: G5, G21, G22, and G33 are recommended for production under drought and optimum conditions, as they showed stable performance across water regimes. Principal component analysis also revealed that MP, GMP, and HM were the only indices that had positive loadings into the first principal component. , Thesis (MSc) -- Faculty of Science and Agriculture, 2023
- Full Text:
- Date Issued: 2023
Local peoples’ knowledge and perceptions of Australian wattle (Acacia) species invasion, ecosystem services and disservices in grassland landscapes, South Africa
- Yapi, Thozamile S, Shackleton, Charlie M, Le Maitre, David C, Dziba, Luthando E
- Authors: Yapi, Thozamile S , Shackleton, Charlie M , Le Maitre, David C , Dziba, Luthando E
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/399791 , vital:69559 , xlink:href="https://doi.org/10.1080/26395916.2023.2177495"
- Description: Many alien tree species were introduced into grassland ecosystems in South Africa by the commercial forestry industry for paper and timber for furniture. Over decades some of these introduced species escaped into neighbouring farms and community land. Adult trees from these alien species now provide other ecosystem services, notably fuelwood. Depending on the spatio-temporal context, many of these species can also negatively affect ecosystem services. We collected interview data from commercial and communal farmers in the upper Umzimvubu catchment in South Africa to compare farmers’ knowledge and perceptions of invasive wattle species invasion and their associated ecosystem services and disservices. Fuelwood and fencing poles were the most common uses of wattle by commercial (83%; 67%) and communal (99%; 49%) farmers. On the other hand, the reduction of grass cover and loss of grazing land were the most commonly mentioned negative impacts of wattles by commercial (83%; 75%) and communal (92%; 80%) farmers. Although both groups recognise the importance of wattles in providing ecosystem services, most communal farmers perceived wattles to have more negative effects than benefits. The findings demonstrate that both farmer groups highly depend on ecosystem services and are affected by disservices of wattles. However, while large-scale commercial households favour the presence of wattles in the landscape, communal households prefer complete removal of the wattles from the landscape. This may be due to lack of locally available alternative options or inability to replace or purchase ecosystem services affected by wattles from other sources or markets like commercial farmers.
- Full Text:
- Date Issued: 2023
- Authors: Yapi, Thozamile S , Shackleton, Charlie M , Le Maitre, David C , Dziba, Luthando E
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/399791 , vital:69559 , xlink:href="https://doi.org/10.1080/26395916.2023.2177495"
- Description: Many alien tree species were introduced into grassland ecosystems in South Africa by the commercial forestry industry for paper and timber for furniture. Over decades some of these introduced species escaped into neighbouring farms and community land. Adult trees from these alien species now provide other ecosystem services, notably fuelwood. Depending on the spatio-temporal context, many of these species can also negatively affect ecosystem services. We collected interview data from commercial and communal farmers in the upper Umzimvubu catchment in South Africa to compare farmers’ knowledge and perceptions of invasive wattle species invasion and their associated ecosystem services and disservices. Fuelwood and fencing poles were the most common uses of wattle by commercial (83%; 67%) and communal (99%; 49%) farmers. On the other hand, the reduction of grass cover and loss of grazing land were the most commonly mentioned negative impacts of wattles by commercial (83%; 75%) and communal (92%; 80%) farmers. Although both groups recognise the importance of wattles in providing ecosystem services, most communal farmers perceived wattles to have more negative effects than benefits. The findings demonstrate that both farmer groups highly depend on ecosystem services and are affected by disservices of wattles. However, while large-scale commercial households favour the presence of wattles in the landscape, communal households prefer complete removal of the wattles from the landscape. This may be due to lack of locally available alternative options or inability to replace or purchase ecosystem services affected by wattles from other sources or markets like commercial farmers.
- Full Text:
- Date Issued: 2023
Love at first bite? Pre-release surveys reveal a novel association between a native weevil and the invasive Nymphaea mexicana Zuccarini (Nymphaeaceae) in South Africa
- Reid, Megan, Hill, Martin P, Coetzee, Julie A
- Authors: Reid, Megan , Hill, Martin P , Coetzee, Julie A
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/416866 , vital:71392 , xlink:href="https://hdl.handle.net/10520/ejc-ento_v31_n1_a19"
- Description: Classical biological control aims to suppress alien invasive plant populations by introducing host-specific natural enemies from the native range. This relies on the assumption that invasive plant populations in the invaded range benefit from the release of natural enemies. Pre-release surveys in the invaded range are a useful way to determine if enemy release applies to a particular invasive alien plant, and to determine what other factors may contribute to the invasion. Similarly, pre-release surveys gather information that can be used to compare invaded sites before and after the release of biological control agents and may also identify whether natural enemies have been accidentally introduced into the country. Pre-release surveys were conducted in South Africa on the invasive Nymphaea mexicana Zuccarini (Nymphaeaceae) to gather such information about this species, for which a biological control programme is being developed. There was lower diversity and abundance of herbivores in the native range compared to South Africa, suggesting that N. mexicana does experience enemy release at most sites in South Africa. This support for the enemy release hypothesis justifies the investment in biological control for its management. However, a native weevil, Bagous longulus Gyllenhal (Coleoptera: Curculionidae), was found feeding and reproducing on N. mexicana at three sites, resulting in damage to the leaves and suggesting that a novel association has formed between these species. Bagous longulus may have potential to be distributed to sites of N. mexicana where it is not present, though further investigation is necessary to confirm if its host range is suitable for this to be a safe endeavour. With the exception of sites where B. longulus was present, leaf sizes were large and damage was low, and there is no evidence that any natural enemies have been accidentally introduced from the native range. Findings such as these emphasise the importance of conducting thorough surveys during the development of biological control programmes.
- Full Text:
- Date Issued: 2023
- Authors: Reid, Megan , Hill, Martin P , Coetzee, Julie A
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/416866 , vital:71392 , xlink:href="https://hdl.handle.net/10520/ejc-ento_v31_n1_a19"
- Description: Classical biological control aims to suppress alien invasive plant populations by introducing host-specific natural enemies from the native range. This relies on the assumption that invasive plant populations in the invaded range benefit from the release of natural enemies. Pre-release surveys in the invaded range are a useful way to determine if enemy release applies to a particular invasive alien plant, and to determine what other factors may contribute to the invasion. Similarly, pre-release surveys gather information that can be used to compare invaded sites before and after the release of biological control agents and may also identify whether natural enemies have been accidentally introduced into the country. Pre-release surveys were conducted in South Africa on the invasive Nymphaea mexicana Zuccarini (Nymphaeaceae) to gather such information about this species, for which a biological control programme is being developed. There was lower diversity and abundance of herbivores in the native range compared to South Africa, suggesting that N. mexicana does experience enemy release at most sites in South Africa. This support for the enemy release hypothesis justifies the investment in biological control for its management. However, a native weevil, Bagous longulus Gyllenhal (Coleoptera: Curculionidae), was found feeding and reproducing on N. mexicana at three sites, resulting in damage to the leaves and suggesting that a novel association has formed between these species. Bagous longulus may have potential to be distributed to sites of N. mexicana where it is not present, though further investigation is necessary to confirm if its host range is suitable for this to be a safe endeavour. With the exception of sites where B. longulus was present, leaf sizes were large and damage was low, and there is no evidence that any natural enemies have been accidentally introduced from the native range. Findings such as these emphasise the importance of conducting thorough surveys during the development of biological control programmes.
- Full Text:
- Date Issued: 2023
Molecular characterization of integrons and their associated gene cassettes in multidrug-resistant enterobacteriaceae isolates from environmental sources and the exploration of antibiotic combination against some resistant strains
- Fadare, Folake Temitope https://orcid.org/0000-0001-5779-9798
- Authors: Fadare, Folake Temitope https://orcid.org/0000-0001-5779-9798
- Date: 2023
- Subjects: Enterobacteriaceae , Molecular microbiology , Enterobacteria
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10353/27809 , vital:69942
- Description: Globally, the increasing rate of antimicrobial resistance against our currently available drugs has been a serious public concern. Due to the selective nature of antibiotics, bacteria are expected to develop resistance against them over time, but the current scourge of antimicrobial resistance is aggravated by factors other than the expected evolutionary trend. The use and overuse of antibiotics in clinical and agricultural contexts have led to the fast rise of multidrug-resistant MDR microorganisms. A scenario that necessitates an upsurge in the clinical failures observed with our current drug arsenals is expected to rise if left unchecked. One of the significant drivers implicated in the spread of antimicrobial resistance genes is the integrons. These are mobile genetic elements found on pathogenicity islands, transposons, and plasmids, easing their distribution among various bacteria. They are considered efficient gene expression systems that naturally capture, integrate gene cassettes GCs and immediately express the captured antimicrobial resistance genes on the GCs due to the inherent promoters on their structures. Integrons have been known to confer resistance against most classes of antibiotics. These include all known β-lactams, chloramphenicol, trimethoprim, erythromycin, aminoglycosides, quinolones, streptothricin, lincomycin, rifampicin, fosfomycin, and antiseptics of the quaternary ammonium compound family. They have been detected in bacterial populations under direct or indirect antibiotic pressure in clinical, agricultural, and environmental contexts. The emergence of MDR in Enterobacteriaceae is a critical public health issue that has attracted the World Health Organization WHO, which classified them as one of the critical priority pathogens urgently requiring new antibiotics. The resistance phenomenon has proven most of the current antibiotics ineffective, further compounded by the slow pace of the discovery of new antibiotics, necessitating the hunt for new, practical remedies. One of such is the exploration of synergy among existing antibiotics. Two medications combined have a higher impact, thereby allowing current antibiotics to be salvaged for use in treating MDR bacteria, even if the bacteria are resistant against one or both antibiotics separately. Hence, this research focused on the occurrence and prevalence of multidrug resistance and the characterization of integrons and their associated gene cassettes in members of Enterobacteriaceae, including Klebsiella pneumoniae, Klebsiella oxytoca, Enterobacter cloacae, Escherichia coli, and Citrobacter spp. recovered from animal droppings, rivers, and effluents of hospital and wastewater treatment plants in Eastern Cape Province, South Africa. The inhibitory effect of combining two drugs belonging to different antibiotic classes to obtain a possible potentiating effect against some multidrug-resistant Enterobacteriaceae isolates harbouring integrons were examined and studied. The isolates were identified using the conventional molecular Polymerase Chain Reaction with specific primers. The antimicrobial resistance profile and the production of Extended-spectrum and metallo β-lactamase were detected using disk diffusion technique DDT, double-disk synergy test DDST, and ethylenediaminetetraacetic acid EDTA tests, respectively. The PCR-based screening method, DNA sequencing analyses, and restriction fragment length polymorphism RFLP were used to characterize the integrons and their associated GCs. Furthermore, Enterobacterial Repetitive Intergenic Consensus ERIC PCR determined the genotypic relationships between some specific species. The various antibiotics' minimum inhibitory concentration MIC was determined using the broth microdilution, while the checkerboard method was used to determine the fractional inhibitory concentration indices FICIs. The time-kill assays TKAs were further used to confirm the synergism observed from the checkerboard assays. Most of the isolates were resistant against most antibiotics tested and were considered MDR. The least resistance was observed against imipenem, a carbapenem, one of the drugs of last resort. Also present were the ESBL and MBL producers, with a few isolates co-producing the enzymes. A high prevalence of integrons was observed in the isolates, with class 1 integrons being the most frequently detected. Some isolates co-harboured the intI1 and intI2 genes and were classified as class1 plus 2 integrons. Although Citrobacter spp. had the least number of isolates among the Enterobacteriaceae studied, it harboured the most diverse gene cassette arrays. The various gene cassette arrays were identified as follows: For Klebsiella spp. Aac 6 Ib, aadA1 dfrA1, and dfrA1 sat2; for Citrobacter spp., dfrA5 aac3 Ib, aac6 ib, aadA1dfrA1 aadA1, aadA1-dfrA1, aadA5 dfrA17, and dfrA21-aac3-Ib; for E. coli dfrA21- aac-3-Ib, dfrA5-aac-3-Ib, aadA1 dfrA1, and aadA5 dfrA17 and for E. cloacae aadA1 dfrA1, dfrA7 dfrA21 dfrA5 aac 3 Ib, and dfrA1 sat2. The GC array dfrA1 sat2 was the only array detected in class 2 integrons which are analogous to that found in Tn7, dfrA1-sat2-aadA1, with the deletion of the last GC aadA1. These detected GCs confer resistance against aminoglycosides, including streptomycin and spectinomycin, and trimethoprim, further increasing the resistance spectrum of the bacterial species harbouring them. The detection of integrons and their associated GC and the presence of these β-lactamases is also associated with coresistance against other classes of antibiotics by bacterial species harbouring them, further limiting treatment options. The checkerboard assays combining antibiotics against these drug-resistant integron harbouring Enterobacteriaceae revealed that 26.3 percent 10 over 38 of the interactions were categorized as synergistic, while 73.7 percent 28 over 38 were indifferent. None of the combinations was antagonistic. The TKAs revealed all the synergistic interactions as bactericidal. Therefore, the combinations of gentamicin with tetracycline, ciprofloxacin, and ceftazidime against Multidrug-resistant MDR Klebsiella pneumoniae; tetracycline-ceftazidime combination against MDR Escherichia coli, colistin combinations with ceftazidime and gentamicin, and tetracycline-gentamicin combinations against MDR Citrobacter freundii may be future therapeutic alternatives. , Thesis (MSci) -- Faculty of Science and Agriculture, 2023
- Full Text:
- Date Issued: 2023
- Authors: Fadare, Folake Temitope https://orcid.org/0000-0001-5779-9798
- Date: 2023
- Subjects: Enterobacteriaceae , Molecular microbiology , Enterobacteria
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10353/27809 , vital:69942
- Description: Globally, the increasing rate of antimicrobial resistance against our currently available drugs has been a serious public concern. Due to the selective nature of antibiotics, bacteria are expected to develop resistance against them over time, but the current scourge of antimicrobial resistance is aggravated by factors other than the expected evolutionary trend. The use and overuse of antibiotics in clinical and agricultural contexts have led to the fast rise of multidrug-resistant MDR microorganisms. A scenario that necessitates an upsurge in the clinical failures observed with our current drug arsenals is expected to rise if left unchecked. One of the significant drivers implicated in the spread of antimicrobial resistance genes is the integrons. These are mobile genetic elements found on pathogenicity islands, transposons, and plasmids, easing their distribution among various bacteria. They are considered efficient gene expression systems that naturally capture, integrate gene cassettes GCs and immediately express the captured antimicrobial resistance genes on the GCs due to the inherent promoters on their structures. Integrons have been known to confer resistance against most classes of antibiotics. These include all known β-lactams, chloramphenicol, trimethoprim, erythromycin, aminoglycosides, quinolones, streptothricin, lincomycin, rifampicin, fosfomycin, and antiseptics of the quaternary ammonium compound family. They have been detected in bacterial populations under direct or indirect antibiotic pressure in clinical, agricultural, and environmental contexts. The emergence of MDR in Enterobacteriaceae is a critical public health issue that has attracted the World Health Organization WHO, which classified them as one of the critical priority pathogens urgently requiring new antibiotics. The resistance phenomenon has proven most of the current antibiotics ineffective, further compounded by the slow pace of the discovery of new antibiotics, necessitating the hunt for new, practical remedies. One of such is the exploration of synergy among existing antibiotics. Two medications combined have a higher impact, thereby allowing current antibiotics to be salvaged for use in treating MDR bacteria, even if the bacteria are resistant against one or both antibiotics separately. Hence, this research focused on the occurrence and prevalence of multidrug resistance and the characterization of integrons and their associated gene cassettes in members of Enterobacteriaceae, including Klebsiella pneumoniae, Klebsiella oxytoca, Enterobacter cloacae, Escherichia coli, and Citrobacter spp. recovered from animal droppings, rivers, and effluents of hospital and wastewater treatment plants in Eastern Cape Province, South Africa. The inhibitory effect of combining two drugs belonging to different antibiotic classes to obtain a possible potentiating effect against some multidrug-resistant Enterobacteriaceae isolates harbouring integrons were examined and studied. The isolates were identified using the conventional molecular Polymerase Chain Reaction with specific primers. The antimicrobial resistance profile and the production of Extended-spectrum and metallo β-lactamase were detected using disk diffusion technique DDT, double-disk synergy test DDST, and ethylenediaminetetraacetic acid EDTA tests, respectively. The PCR-based screening method, DNA sequencing analyses, and restriction fragment length polymorphism RFLP were used to characterize the integrons and their associated GCs. Furthermore, Enterobacterial Repetitive Intergenic Consensus ERIC PCR determined the genotypic relationships between some specific species. The various antibiotics' minimum inhibitory concentration MIC was determined using the broth microdilution, while the checkerboard method was used to determine the fractional inhibitory concentration indices FICIs. The time-kill assays TKAs were further used to confirm the synergism observed from the checkerboard assays. Most of the isolates were resistant against most antibiotics tested and were considered MDR. The least resistance was observed against imipenem, a carbapenem, one of the drugs of last resort. Also present were the ESBL and MBL producers, with a few isolates co-producing the enzymes. A high prevalence of integrons was observed in the isolates, with class 1 integrons being the most frequently detected. Some isolates co-harboured the intI1 and intI2 genes and were classified as class1 plus 2 integrons. Although Citrobacter spp. had the least number of isolates among the Enterobacteriaceae studied, it harboured the most diverse gene cassette arrays. The various gene cassette arrays were identified as follows: For Klebsiella spp. Aac 6 Ib, aadA1 dfrA1, and dfrA1 sat2; for Citrobacter spp., dfrA5 aac3 Ib, aac6 ib, aadA1dfrA1 aadA1, aadA1-dfrA1, aadA5 dfrA17, and dfrA21-aac3-Ib; for E. coli dfrA21- aac-3-Ib, dfrA5-aac-3-Ib, aadA1 dfrA1, and aadA5 dfrA17 and for E. cloacae aadA1 dfrA1, dfrA7 dfrA21 dfrA5 aac 3 Ib, and dfrA1 sat2. The GC array dfrA1 sat2 was the only array detected in class 2 integrons which are analogous to that found in Tn7, dfrA1-sat2-aadA1, with the deletion of the last GC aadA1. These detected GCs confer resistance against aminoglycosides, including streptomycin and spectinomycin, and trimethoprim, further increasing the resistance spectrum of the bacterial species harbouring them. The detection of integrons and their associated GC and the presence of these β-lactamases is also associated with coresistance against other classes of antibiotics by bacterial species harbouring them, further limiting treatment options. The checkerboard assays combining antibiotics against these drug-resistant integron harbouring Enterobacteriaceae revealed that 26.3 percent 10 over 38 of the interactions were categorized as synergistic, while 73.7 percent 28 over 38 were indifferent. None of the combinations was antagonistic. The TKAs revealed all the synergistic interactions as bactericidal. Therefore, the combinations of gentamicin with tetracycline, ciprofloxacin, and ceftazidime against Multidrug-resistant MDR Klebsiella pneumoniae; tetracycline-ceftazidime combination against MDR Escherichia coli, colistin combinations with ceftazidime and gentamicin, and tetracycline-gentamicin combinations against MDR Citrobacter freundii may be future therapeutic alternatives. , Thesis (MSci) -- Faculty of Science and Agriculture, 2023
- Full Text:
- Date Issued: 2023
Nagoya Protocol and Africa’s willingness to share biological control agents, are we deterred by barriers instead of using opportunities to work together?
- Ivey, Philip J, Hill, Martin P, Voukeng, Sonia Nadege Kenfack, Weaver, Kim N
- Authors: Ivey, Philip J , Hill, Martin P , Voukeng, Sonia Nadege Kenfack , Weaver, Kim N
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/418040 , vital:71503 , xlink:href="https://doi.org/10.1007/s10526-023-10184-8"
- Description: Amongst members of the biological control community there is a range of perceptions regarding the Nagoya Protocol, at best it will hinder access to natural enemies of pests and invasive plants and at worst implementation of the Protocol will prevent access to these resources. In this preliminary study of Africa’s preparedness to implement the Nagoya Protocol and control access to potential biological control agents, we found that several countries have not yet established procedures and policies in this regard. Several factors including lack of awareness, insufficient relevant information and lack of capacity may cause delay in countries implementing access and benefit sharing legislation and processes. The lack of preparedness provides an opportunity for the research community to work with government officials to facilitate future access to natural enemies to act as biological control agents on invasive plants and agricultural pests. Collaboration between researchers, managers and bureaucrats in support of African countries could lead to collective action that develops policies and implements processes to foster exploration of African biodiversity. This collaboration could also foster the sharing of biological control agents that will benefit Africa through integrated pest management in agriculture, protection of human lives and livelihoods, and reduction of the impact of invasive alien species on biodiversity and environmental infrastructure.
- Full Text:
- Date Issued: 2023
- Authors: Ivey, Philip J , Hill, Martin P , Voukeng, Sonia Nadege Kenfack , Weaver, Kim N
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/418040 , vital:71503 , xlink:href="https://doi.org/10.1007/s10526-023-10184-8"
- Description: Amongst members of the biological control community there is a range of perceptions regarding the Nagoya Protocol, at best it will hinder access to natural enemies of pests and invasive plants and at worst implementation of the Protocol will prevent access to these resources. In this preliminary study of Africa’s preparedness to implement the Nagoya Protocol and control access to potential biological control agents, we found that several countries have not yet established procedures and policies in this regard. Several factors including lack of awareness, insufficient relevant information and lack of capacity may cause delay in countries implementing access and benefit sharing legislation and processes. The lack of preparedness provides an opportunity for the research community to work with government officials to facilitate future access to natural enemies to act as biological control agents on invasive plants and agricultural pests. Collaboration between researchers, managers and bureaucrats in support of African countries could lead to collective action that develops policies and implements processes to foster exploration of African biodiversity. This collaboration could also foster the sharing of biological control agents that will benefit Africa through integrated pest management in agriculture, protection of human lives and livelihoods, and reduction of the impact of invasive alien species on biodiversity and environmental infrastructure.
- Full Text:
- Date Issued: 2023
Photoantimicrobial activity of Schiff-base morpholino phthalocyanines against drug resistant micro-organisms in their planktonic and biofilm forms
- Sindelo, Azole, Sen, Pinar, Nyokong, Tebello
- Authors: Sindelo, Azole , Sen, Pinar , Nyokong, Tebello
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/360437 , vital:65088 , xlink:href="https://doi.org/10.1016/j.pdpdt.2023.103519"
- Description: Antimicrobial photodynamic inactivation (aPDI) is a treatment for the eradication of drug-resistant micro-organisms. One of the advantages of this technique, is that there is minimal possibility of microbial resistance. Hence, herein, the preparation and characterization of novel neutral and cationic morpholine containing Schiff base phthalocyanines are reported. The cationic complexes gave moderate singlet oxygen quantum yields (ΦΔ) of ∼0.2 in aqueous media. Conversely, the neutral complexes generated very low ΦΔ values making them very poor candidates for antimicrobial studies. The cationic phthalocyanines showed excellent photodynamic activity against planktonic cells of all micro-organisms (Candida albicans, Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, Salmonella enterica subspecies enterica serovar Choleraesuis, vancomycin-resistant Enterococcus faecium, and methicillin-resistant Staphylococcus aureus). The efficiency of aPDI was shown to be both concentration and light-dose-dependent. Mono biofilms were susceptible when treated with 200 µM of cationic Pcs at 108 J/cm2. However, ∼10% of the mixed biofilm survived after treatment.
- Full Text:
- Date Issued: 2023
- Authors: Sindelo, Azole , Sen, Pinar , Nyokong, Tebello
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/360437 , vital:65088 , xlink:href="https://doi.org/10.1016/j.pdpdt.2023.103519"
- Description: Antimicrobial photodynamic inactivation (aPDI) is a treatment for the eradication of drug-resistant micro-organisms. One of the advantages of this technique, is that there is minimal possibility of microbial resistance. Hence, herein, the preparation and characterization of novel neutral and cationic morpholine containing Schiff base phthalocyanines are reported. The cationic complexes gave moderate singlet oxygen quantum yields (ΦΔ) of ∼0.2 in aqueous media. Conversely, the neutral complexes generated very low ΦΔ values making them very poor candidates for antimicrobial studies. The cationic phthalocyanines showed excellent photodynamic activity against planktonic cells of all micro-organisms (Candida albicans, Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, Salmonella enterica subspecies enterica serovar Choleraesuis, vancomycin-resistant Enterococcus faecium, and methicillin-resistant Staphylococcus aureus). The efficiency of aPDI was shown to be both concentration and light-dose-dependent. Mono biofilms were susceptible when treated with 200 µM of cationic Pcs at 108 J/cm2. However, ∼10% of the mixed biofilm survived after treatment.
- Full Text:
- Date Issued: 2023
Photodynamic inactivation of methicillin-resistant Staphylococcus aureus using pyrrolidinium containing Schiff base phthalocyanines
- Sindelo, Azole, Sen, Pinar, Nyokong, Tebello
- Authors: Sindelo, Azole , Sen, Pinar , Nyokong, Tebello
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/360449 , vital:65089 , xlink:href="https://doi.org/10.1016/j.jphotochem.2022.114535"
- Description: New tetra-substituted zinc and indium Schiff base phthalocyanines (ZnPc and InPc, respectively) are synthesized and characterized herein. The ethyl pyrrolidine (ZnPc-2, InPc-2) and propyl pyrrolidine (ZnPc-3, InPc-3) substituted Schiff base Pcs were reacted with methyl iodide to form their cationic derivatives (ZnPc-2Q, InPc-2Q, ZnPc-3Q, and InPc-3Q, respectively). The photophysical and photochemical properties of the Pcs were studied. The cationic Pcs generated higher singlet oxygen quantum yield in aqueous media than the neutral Pcs. The photoinactivation of Methicillin-resistant Staphylococcus aureus (MRSA) and Methicillin-sensitive Staphylococcus aureus (MSSA) strains was evaluated. 5 µM ZnPc-3Q and InPc-3Q inactivated 100 % of the MSSA and MRSA while 5 µM ZnPc-2Q and InPc-2Q eradicated 100 % for MSSA and 97.2 % and 98.7 % (respectively) of the MRSA. The photodynamic antimicrobial chemotherapy studies depended on singlet oxygen ability, the charges, and the extension of the alkyl groups.
- Full Text:
- Date Issued: 2023
- Authors: Sindelo, Azole , Sen, Pinar , Nyokong, Tebello
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/360449 , vital:65089 , xlink:href="https://doi.org/10.1016/j.jphotochem.2022.114535"
- Description: New tetra-substituted zinc and indium Schiff base phthalocyanines (ZnPc and InPc, respectively) are synthesized and characterized herein. The ethyl pyrrolidine (ZnPc-2, InPc-2) and propyl pyrrolidine (ZnPc-3, InPc-3) substituted Schiff base Pcs were reacted with methyl iodide to form their cationic derivatives (ZnPc-2Q, InPc-2Q, ZnPc-3Q, and InPc-3Q, respectively). The photophysical and photochemical properties of the Pcs were studied. The cationic Pcs generated higher singlet oxygen quantum yield in aqueous media than the neutral Pcs. The photoinactivation of Methicillin-resistant Staphylococcus aureus (MRSA) and Methicillin-sensitive Staphylococcus aureus (MSSA) strains was evaluated. 5 µM ZnPc-3Q and InPc-3Q inactivated 100 % of the MSSA and MRSA while 5 µM ZnPc-2Q and InPc-2Q eradicated 100 % for MSSA and 97.2 % and 98.7 % (respectively) of the MRSA. The photodynamic antimicrobial chemotherapy studies depended on singlet oxygen ability, the charges, and the extension of the alkyl groups.
- Full Text:
- Date Issued: 2023
Short Course Handouts Bundle for the Training of Trainers Course: Introductory course to facilitating social learning and stakeholder engagement in natural resource management contexts
- Weaver, Martin, Rosenberg, Eureta, Cockburn, Jessica J, Thifhulufhelwi, R, Chetty, Preven, Mponwana, Maletje, Mvulane, P
- Authors: Weaver, Martin , Rosenberg, Eureta , Cockburn, Jessica J , Thifhulufhelwi, R , Chetty, Preven , Mponwana, Maletje , Mvulane, P
- Date: 2023
- Subjects: Social learning , Stakeholder management , Natural resources Management , Community education
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/338822 , vital:62456 , ISBN
- Description: This document is a compilation of the course handouts (materials) developed and produced for the “Training of Trainers” Short Course – the full title of which is the: “Introductory course to facilitating social learning and stakeholder engagement in natural resource management contexts”.
- Full Text:
- Date Issued: 2023
- Authors: Weaver, Martin , Rosenberg, Eureta , Cockburn, Jessica J , Thifhulufhelwi, R , Chetty, Preven , Mponwana, Maletje , Mvulane, P
- Date: 2023
- Subjects: Social learning , Stakeholder management , Natural resources Management , Community education
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/338822 , vital:62456 , ISBN
- Description: This document is a compilation of the course handouts (materials) developed and produced for the “Training of Trainers” Short Course – the full title of which is the: “Introductory course to facilitating social learning and stakeholder engagement in natural resource management contexts”.
- Full Text:
- Date Issued: 2023