Insect Physiology, Cytology and Biochemistry: ENT 505
- Authors: Stemele, M A , Olckers, T
- Date: 2011-06
- Language: English
- Type: Examination paper
- Identifier: vital:17895 , http://hdl.handle.net/10353/d1011064
- Description: Insect Physiology, Cytology and Biochemistry: ENT 505, honuors examination June 2011.
- Full Text: false
- Date Issued: 2011-06
Insects Habitats and Adaptations: ENT 313
- Authors: Mdlangu, T , Olckers, T
- Date: 2011-06
- Language: English
- Type: Examination paper
- Identifier: vital:17894 , http://hdl.handle.net/10353/d1011063
- Description: Insects Habitats and Adaptations: ENT 313, degree examination June 2011.
- Full Text: false
- Date Issued: 2011-06
Insect Behavior and Ecology: ENT 322
- Authors: Mdlangu, T , Olckers, T
- Date: 2010-11
- Language: English
- Type: Examination paper
- Identifier: vital:17898 , http://hdl.handle.net/10353/d1011073
- Description: Insect Behavior and Ecology: ENT 322, degree examination November 2010.
- Full Text: false
- Date Issued: 2010-11
Pest Management Theory and Practices: ENT 323
- Authors: Mdlangu, T , Olckers, T
- Date: 2010-11
- Language: English
- Type: Examination paper
- Identifier: vital:17899 , http://hdl.handle.net/10353/d1011075
- Description: Pest Management Theory and Practices: ENT 323, degree examination November 2010.
- Full Text: false
- Date Issued: 2010-11
Insect herbivores associated with indigenous species of Solanum (Solanaceae) in the Transvaal, South Africa, and in Namibia
- Authors: Olckers, T , Hulley, Patrick E , Hill, Martin P
- Date: 1995
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/451440 , vital:75049 , https://hdl.handle.net/10520/AJA10213589_108
- Description: Several indigenous Solanum (Solanaceae) species were surveyed in the Transvaal and Namibia as part of a broader study of the insect herbivores associated with indigenous, as well as weedy and cultivated exotic, solanurns in southern Africa. Insects were collected on three Solanum species in the Transvaal and on 10 in Namibia. Solanum panduriforme E. Mey. and S. incanum L. were abundant in both regions, while S. capense L. was the most common species in Namibia. These three Solanum species supported an abundance of insect herbivores, which included many oligophages found on solanurns in other regions of South Africa. Most of the Solanum insect species were found on a wide range of host plants, in a variety of habitats and under various climatic conditions.
- Full Text:
- Date Issued: 1995
Host specificity tests on leaf-feeding insects aberrations from the use of excised leaves
- Authors: Olckers, T , Hulley, Patrick E
- Date: 1994
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/452340 , vital:75121 , https://journals.co.za/doi/pdf/10.10520/AJA10213589_137
- Description: Starvation tests, in which herbivorous insects are confined to plants under cage conditions, are integral to determining the host range and suitability of candidate agents for weed biocontrol (Cullen 1990). The acceptance or rejection of test plants under these artificial conditions can, however, be influenced by the quality of the plants presented (Shepherd 1990); starvation tests on leaf-feeding insects are often carried out with bouquets or excised leaves as opposed to whole plants. This study presents the results of two independent experiments that illustrate potential problems associated with the use of excised leaves during host specificity tests.
- Full Text:
- Date Issued: 1994
Resolving ambiguous results of host-specificity tests the case of two Leptinotarsa species (Coleoptera: Chrysomelidae) for biological control of Solanum elaeagnifolium Cavanilles (Solanaceae) in South Africa
- Authors: Olckers, T , Hulley, Patrick E
- Date: 1994
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/452358 , vital:75122 , https://hdl.handle.net/10520/AJA10213589_421
- Description: Two leaf-feeding chrysomelids from North America, Leptinotarsa texana (Schaeffer) and Leptinotarsa defecta (Stal), are promising candidates for the biological control of Solanum elaeagnifolium Cavanilles (Solanaceae) in South Africa. Permission for release was delayed because the beetles fed on cultivated eggplant (Solanum melongena Linnaeus) under cage conditions. After considerable deliberation and further investigation, it was concluded that the results of the cage tests had been overemphasized. The beetles were cleared for release in South Africa on the following grounds: (i) neither Leptinotarsa species attacks eggplant in their native North American habitats; (ii) in South Africa, many insect herbivores of Solanaceae feed on eggplant in cultivation but cause minor damage relative to cosmopolitan polyphagous pests; (iii) as with L. texana and L. defecta, Conchyloctenia tigrina Olivier, a South African chrysomelid that also occurs on eggplant in cultivation, fed on eggplant in indoor cages, but preferred its natural Solanum hosts in large outdoor cages; (iv) eggplant cultivation methods include crop rotation and severe pesticide regimes, which should exclude Leptinotarsa along with the other insects.
- Full Text:
- Date Issued: 1994
Insect herbivores on the exotic weeds Solanum elaeagnifolium Cavanilles and S. sisymbriifolium Lamarck (Solanaceae) in South Africa
- Authors: Hill, Martin P , Hulley, Patrick E , Olckers, T
- Date: 1993
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/451454 , vital:75050 , https://hdl.handle.net/10520/AJA10213589_58
- Description: In South Africa, the weeds Solanum elaeagnifolium Cavanilles and S. sisymbriifolium Lamarck (Solanaceae) sustain little observable damage from herbivorous insects. Relatively few insect species occur on these plants and at low individual densities. Since native insects are not important in the natural control of S. elaeagnifolium and S. sisymbriifolium, additional agents should be imported for the biological control of these weeds. The absence of important local herbivores means that the possibility of interaction between these and potential biological control agents need not be a consideration in choosing the agents. The nature and numbers of the insect herbivores of S. elaeagnifolium and S. sisymbriifolium are compared with those on another solanaceous weed, S. mauritianum Scopoli, and on native Solanum species. These insect species are discussed relative to plant defence mechanisms.
- Full Text:
- Date Issued: 1993