More than a century of biological control against invasive alien plants in South Africa: a synoptic view of what has been accomplished
- Hill, Martin P, Moran, V Clifford, Hoffmann, John H, Neser, Stefan, Zimmermann, Helmuth G, Simelane, David O, Klein, Hildegard, Zachariades, Costas, Wood, Alan R, Byrne, Marcus J, Paterson, Iain D, Martin, Grant D, Coetzee, Julie A
- Authors: Hill, Martin P , Moran, V Clifford , Hoffmann, John H , Neser, Stefan , Zimmermann, Helmuth G , Simelane, David O , Klein, Hildegard , Zachariades, Costas , Wood, Alan R , Byrne, Marcus J , Paterson, Iain D , Martin, Grant D , Coetzee, Julie A
- Date: 2020
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/176260 , vital:42679 , ISBN 978-3-030-32394-3 , 10.1007/978-3-030-32394-3
- Description: Invasive alien plant species negatively affect agricultural production, degrade conservation areas, reduce water supplies, and increase the intensity of wild fires. Since 1913, biological control agents ie plant-feeding insects, mites, and fungal pathogens, have been deployed in South Africa to supplement other management practices (herbicides and mechanical controls) used against these invasive plant species. We do not describe the biological control agent species.
- Full Text: false
- Date Issued: 2020
- Authors: Hill, Martin P , Moran, V Clifford , Hoffmann, John H , Neser, Stefan , Zimmermann, Helmuth G , Simelane, David O , Klein, Hildegard , Zachariades, Costas , Wood, Alan R , Byrne, Marcus J , Paterson, Iain D , Martin, Grant D , Coetzee, Julie A
- Date: 2020
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/176260 , vital:42679 , ISBN 978-3-030-32394-3 , 10.1007/978-3-030-32394-3
- Description: Invasive alien plant species negatively affect agricultural production, degrade conservation areas, reduce water supplies, and increase the intensity of wild fires. Since 1913, biological control agents ie plant-feeding insects, mites, and fungal pathogens, have been deployed in South Africa to supplement other management practices (herbicides and mechanical controls) used against these invasive plant species. We do not describe the biological control agent species.
- Full Text: false
- Date Issued: 2020
Biological control of cactaceae in South Africa
- Paterson, Iain D, Hoffmann, John H, Klein, Hildegard, Mathenge, C W, Neser, Stephan, Zimmermann, Helmuth G
- Authors: Paterson, Iain D , Hoffmann, John H , Klein, Hildegard , Mathenge, C W , Neser, Stephan , Zimmermann, Helmuth G
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/452308 , vital:75119 , https://hdl.handle.net/10520/EJC32918
- Description: This review is a summary of developments that have contributed to the success of several biological control programmes against invasive cactus species (Cactaceae) that have been worked on in South Africa over the last 12 years. Six potential biological control agents have been identified for the control of Pereskia aculeata Mill. and molecular studies have identified the origin of the South African P. aculeata population. Host-specificity testing is now required for the three most promising of these agents. The successful biological control programme against Opuntia stricta (Haw.) Haw. has resulted in a change in management strategies against this weed in the Kruger National Park and the control of O. stricta is now almost entirely reliant on biological control. Taxonomic problems associated with the identification of Cylindropuntia fulgida var. fulgida (Engelm.) F.M.Knuth var. fulgida have been resolved and an appropriate cochineal insect (Hemiptera: Dactylopiidae) biotype has been released, resulting in substantial declines in Cyl. fulgida var. fulgida populations. A long-term monitoring programme has been initiated to evaluate the progress of this new cochineal insect biotype. The Harrisia mealybug, Hypogeococcus pungens Granara de Willink (Hemiptera: Pseudococcidae), which was originally released on Harrisia martinii (Labour.) Britton and Rose has been collected and redistributed onto Cereus jamacaru DC., where it reduces fruit production and leads to the death of both seedlings and large plants. Resolving taxonomic problems to ensure the correct identification of plant species and the most appropriate biological control biotypes have been key issues that have led to the successful control of several cactaceous weed species in South Africa.
- Full Text:
- Date Issued: 2011
- Authors: Paterson, Iain D , Hoffmann, John H , Klein, Hildegard , Mathenge, C W , Neser, Stephan , Zimmermann, Helmuth G
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/452308 , vital:75119 , https://hdl.handle.net/10520/EJC32918
- Description: This review is a summary of developments that have contributed to the success of several biological control programmes against invasive cactus species (Cactaceae) that have been worked on in South Africa over the last 12 years. Six potential biological control agents have been identified for the control of Pereskia aculeata Mill. and molecular studies have identified the origin of the South African P. aculeata population. Host-specificity testing is now required for the three most promising of these agents. The successful biological control programme against Opuntia stricta (Haw.) Haw. has resulted in a change in management strategies against this weed in the Kruger National Park and the control of O. stricta is now almost entirely reliant on biological control. Taxonomic problems associated with the identification of Cylindropuntia fulgida var. fulgida (Engelm.) F.M.Knuth var. fulgida have been resolved and an appropriate cochineal insect (Hemiptera: Dactylopiidae) biotype has been released, resulting in substantial declines in Cyl. fulgida var. fulgida populations. A long-term monitoring programme has been initiated to evaluate the progress of this new cochineal insect biotype. The Harrisia mealybug, Hypogeococcus pungens Granara de Willink (Hemiptera: Pseudococcidae), which was originally released on Harrisia martinii (Labour.) Britton and Rose has been collected and redistributed onto Cereus jamacaru DC., where it reduces fruit production and leads to the death of both seedlings and large plants. Resolving taxonomic problems to ensure the correct identification of plant species and the most appropriate biological control biotypes have been key issues that have led to the successful control of several cactaceous weed species in South Africa.
- Full Text:
- Date Issued: 2011
A proposed prioritization system for the management of invasive alien plants in South Africa
- Robertson, Mark P, Villet, Martin H, Fairbanks, Dean H K, Henderson, L, Higgins, Simon I, Hoffmann, John H, Le Maitre, David C, Palmer, Anthony R, Riggs, I, Shackleton, Charlie M, Zimmermann, Helmuth G
- Authors: Robertson, Mark P , Villet, Martin H , Fairbanks, Dean H K , Henderson, L , Higgins, Simon I , Hoffmann, John H , Le Maitre, David C , Palmer, Anthony R , Riggs, I , Shackleton, Charlie M , Zimmermann, Helmuth G
- Date: 2003
- Language: English
- Type: Article
- Identifier: vital:6911 , http://hdl.handle.net/10962/d1011872
- Description: Every country has weed species whose presence conflicts in some way with human management objectives and needs. Resources for research and control are limited, so priority should be given to species that are the biggest problem. The prioritization system described in this article was designed to assess objectively research and control priorities of invasive alien plants at a national scale in South Africa. The evaluation consists of seventeen criteria, grouped into five modules, that assess invasiveness, spatial characteristics, potential impact, potential for control, and conflicts of interest for each plant species under consideration. Total prioritization scores, calculated from criterion and module scores, were used to assess a species' priority. Prioritization scores were calculated by combining independent assessments provided by several experts, thus increasing the reliability of the rankings. The total confidence score, a separate index, indicates the reliability and availability of data used to make an assessment. Candidate species for evaluation were identified and assessed by several experts using the prioritization system. The final ranking was made by combining two separate indices, the total prioritization score and the total confidence score. This approach integrates the plant's perceived priority with an index of data reliability. Of the 61 species assessed, those with the highest ranks (Lantana camara, Chromolaena odorata and Opuntia ficus-indica) had high prioritization and high confidence scores, and are thus of most concern. Those species with the lowest ranks, for example, Harrisia martinii, Opuntia spinulifera and Opuntia exaltata, had low prioritization scores and high confidence scores, and thus are of least concern. Our approach to ranking weeds offers several advantages over existing systems because it is designed for multiple assessors based on the Delphi decision-making technique, the criteria contribute equally to the total score, and the system can accommodate incomplete data on a species. Although the choice of criteria may be criticized and the system has certain limitations, it appears to have delivered credible results.
- Full Text:
- Date Issued: 2003
- Authors: Robertson, Mark P , Villet, Martin H , Fairbanks, Dean H K , Henderson, L , Higgins, Simon I , Hoffmann, John H , Le Maitre, David C , Palmer, Anthony R , Riggs, I , Shackleton, Charlie M , Zimmermann, Helmuth G
- Date: 2003
- Language: English
- Type: Article
- Identifier: vital:6911 , http://hdl.handle.net/10962/d1011872
- Description: Every country has weed species whose presence conflicts in some way with human management objectives and needs. Resources for research and control are limited, so priority should be given to species that are the biggest problem. The prioritization system described in this article was designed to assess objectively research and control priorities of invasive alien plants at a national scale in South Africa. The evaluation consists of seventeen criteria, grouped into five modules, that assess invasiveness, spatial characteristics, potential impact, potential for control, and conflicts of interest for each plant species under consideration. Total prioritization scores, calculated from criterion and module scores, were used to assess a species' priority. Prioritization scores were calculated by combining independent assessments provided by several experts, thus increasing the reliability of the rankings. The total confidence score, a separate index, indicates the reliability and availability of data used to make an assessment. Candidate species for evaluation were identified and assessed by several experts using the prioritization system. The final ranking was made by combining two separate indices, the total prioritization score and the total confidence score. This approach integrates the plant's perceived priority with an index of data reliability. Of the 61 species assessed, those with the highest ranks (Lantana camara, Chromolaena odorata and Opuntia ficus-indica) had high prioritization and high confidence scores, and are thus of most concern. Those species with the lowest ranks, for example, Harrisia martinii, Opuntia spinulifera and Opuntia exaltata, had low prioritization scores and high confidence scores, and thus are of least concern. Our approach to ranking weeds offers several advantages over existing systems because it is designed for multiple assessors based on the Delphi decision-making technique, the criteria contribute equally to the total score, and the system can accommodate incomplete data on a species. Although the choice of criteria may be criticized and the system has certain limitations, it appears to have delivered credible results.
- Full Text:
- Date Issued: 2003
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